Tag Archives: PZP

Two year old Pregnant Mare Dies at Palomino Valley Center

12 Jul

Yesterday, after seeing a photo posted by Patty Summerson-Bumgarner on facebook of a dead mare at Palomino Valley Center, I was urged to contact the correctional facility where the foal was taken.  I called them and was told they had no idea what I was talking about.  So I called Palomino Valley Center  775-475-2222  Saturday morning at 11:48 AM to ask about the new foal that was born as mentioned in the news report posted by  KTVN:

BLM Foal Taken to Orphan Care

“Photos surfaced online Saturday of a mare that passed away during childbirth overnight Thursday at the Palomino Valley Bureau of Land Management’s wild horse and burro holding facility. 
John Neill of the Bureau of Land Management confirmed that the 2 year old mare was found deceased when workers arrived early Friday morning. The mother and foal were removed from the pen and the foal was successfully delivered. The foal was taken to Northern Nevada Correctional Center where the BLM has an orphan care program. “

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What’s Wrong with the BLM Wild Horse and Burro Program? LOTS!

20 Apr

While reading Necktag #5846 profile information on the bidding page I realized she was a a young foal when captured and now has spent 5.5 years in short term holding. As I reviewed the Elm Creek, Nebraska photo gallery, I noticed some of the horses available for internet adoption auction had been in short term holding facilities all their lives, 6 years for some while others were “born in a holding facility” and some of these did not indicate which holding facility or the HMA of origin.
It is annoying that they can’t keep good records about the cattle grazing on public lands, or have solid data on the numbers of horses and burros still running free so it’s not new that the Wild Horse and Burro Program cannot track foals in holding pens and know their HMA of origin. Or, maybe they do know but can’t recall or find the missing data? It doesn’t help that any foals born in a holding facility aren’t counted if they are under 6 months old. And if they die, they still don’t count! Yet vetting, food and care during the first six months of their lives is still paid for via tax dollars. What a way to run a federal program! They don’t count everything we pay for….


Gray 6  old mare from Lost Creek (Cyclone Rim) Herd Management Area

Gray 6 old mare from Lost Creek (Cyclone Rim) Herd Management Area

For the past few weeks, I’ve been checking the BLM’s Wild Horse and Burro Internet Adoption pages to see what horses are there and prepare to make some tweets in advance for more exposure to find homes for the wild horses and burros. However, this isn’t easy or quick to do because there are no social media share buttons on their pages!

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Discussion-Education Group on Facebook Discussing PZP Use on Wild Horses

19 Nov

The third band arrive in the trap chute.

The third band arrive in the trap chutte. Triple B, Newark Valley  ©2011 afroditi katsikis

Protect Mustangs™ has started an education and discussion forum on facebook to discuss the use of contraceptives on wild horses and burros.

The forum members have been exploring the pros & cons, myths & facts about Porcine Zona Pellucida (PZP) currently in use on America’s federally protected wild horses and burros on public lands.

Join the discussion in the group or just read the posts and documents there – it’s an open group and everyone is welcome to post the research they’ve found or just read and learn more about PZP and its various forms (Native PZP, PZP22, ZonaStat), research and study reports and much more.

Join the discussion on  Forum on PZP for Wild Horses & Burros on Federal Land



BLM Wild Horse and Burro Myths and Facts are Twisted

19 Sep

Horses crossing a plain near the Simpson Park ...

Horses crossing a plain near the Simpson Park Wilderness Study Area (Photo credit: Wikipedia)

In the lawsuit by the Rock Springs Grazing Assn against the BLM WH&B program – BLM caved in and agreed with the plaintiff more or less. However, it was the BLM WH&B staff that recommended the Rock Springs grazing association file a lawsuit against the BLM. That lawsuit has got to be the shortest lawsuit in which the BLM was named plaintiff. The lawsuits they aggressively litigate,  go on for years and are the ones that wild horse advocates have filed.

The BLM WH&B program has never followed the science, has never asked for or accepted help by those people who really care and know about wild horses and they have loaded their advisory board with ranchers and pro-slaughter folks and not with people who do NOT have affiliation with cattle ranchers or horse slaughter.

This board is totally jaded against wild horses roaming free. BLM Wild Horse and Burro Advisory Board is an expensive farce and adds insult to injury by their recommendations – the latest one is to export 100 burros to Guatamala where they will become beasts of burden. The BLM has also misconstrued the 1971 Wild Horse and Burro act to suit the ranchers, frackers, miners, timber harvesters and solar farm industries but rarely honestly protect the animals they were charged to protect.

Last night while trying to locate the gather report for the Great Divide Basin I stumbled across this page on the BLM website:  Myths and Facts

Many of the ‘Myths’ and facts are BLM interpretations based on the NAS report that was given to the BLM in the summer of 2013.  They  misconstrued the NAS report that came out last year to fit the needs of their other ‘clients’ who don’t have the same federal protection as the wild horses and burros. Makes me wonder who is filling their pockets?

The BLM stated Myths that are facts and facts which are myths for the most part. Some of their references used below are not reliable sources of information.


Myths and Facts

Contact: Tom Gorey, BLM Public Affairs (202-912-7420)

Updated as of August 15, 2014

Myth #1: A report issued in June 2013 by a 14-member research committee of the National Academy of Sciences (NAS) recommended that the BLM stop gathering wild horses and burros from Western public rangelands and let nature cull any excess herds.

Fact: These characterizations are completely erroneous. NAS’s Board on Agricultural and Natural Resources (BANR), which oversees the academy’s natural resource studies, issued a special-edition newsletter in July that said: “Some news accounts have incorrectly reported that the study found that the Bureau should stop gathers and ‘let nature cull any excess herds.’ In fact, the report recommends more intensive management of the horses and burros….” BANR then cited several management measures recommended by the report, including using scientifically rigorous methods to estimate the number of animals on the range; modeling the effects of management actions, such as the use of fertility-control treatments on mares and stallions and the removal of animals through gathers, on wild horse and burro health; and, following gathers, using the available one-year fertility-control vaccine (known as PZP) more widely and consistently to treat some mares.

The 383-page report itself, titled “Using Science to Improve the BLM Wild Horse and Burro Program: A Way Forward,” makes it clear that to “let nature cull any excess herds” is not a viable option. The preface to the report, which does challenge the status quo of wild horse management, goes on to say in the very next sentence: “It is equally evident that the consequences of simply letting horse populations, which increase at a mean annual rate approaching 20 percent, expand to the level of ‘self-limitation’—bringing suffering and death due to disease, dehydration, and starvation accompanied by degradation of the land—are also unacceptable.”


Myth #2: The BLM is selling or sending wild horses to slaughter.

Fact: This charge is absolutely false. The Department of the Interior and the Bureau of Land Management care deeply about the well-being of wild horses, both on and off the range, and it has been and remains the policy of the BLM not to sell or send wild horses or burros to slaughter. Consequently, as the Government Accountability Office noted in a report issued in October 2008, the BLM is not in compliance with a December 2004 amendment (the so-called Burns Amendment to the 1971 Wild Free-Roaming Horses and Burros Act) that directs the Bureau to sell excess horses or burros “without limitation” to any willing buyer.


Myth #3: Horses are held in crowded “holding pens.”

Fact: This assertion is false. The BLM’s short-term holding corrals provide ample space to horses, along with clean feed and water, while long-term holding pastures – large ranches located mainly in Kansas and Oklahoma – permit the horses to roam freely on approximately 289,000 acres of grassland.


Myth #4: Since 1971, the BLM has illegally or improperly taken away more than 20 million acres set aside for wild horses and burros (from 53.8 million acres to 31.6 million acres).

Fact: This claim is false. No specific amount of acreage was “set aside” for the exclusive use of wild horses and burros under the 1971 Wild Free-Roaming Horses and Burros Act. The Act directed the BLM to determine the areas where horses and burros were found roaming and to manage them “in a manner that is designed to achieve and maintain a thriving natural ecological balance on the public lands.” The law also stipulated in Section 1339 that “Nothing in this Act shall be construed to authorize the [Interior] Secretary to relocate wild free-roaming horses or burros to areas of the public lands where they do not presently exist.” Of the 22.2 million acres no longer managed for wild horse and burro use:

6.7 million acres were never under BLM management.
Of the 15.5 million other acres of land under BLM management:
48.6 percent (7,522,100 acres) were intermingled (“checkerboard”) land ownerships or areas where water was not owned or controlled by the BLM, which made management infeasible;
13.5 percent (2,091,709 acres) were lands transferred out of the BLM’s ownership to other agencies, both Federal and state through legislation or exchange;
10.6 percent (1,645,758 acres) were lands where there were substantial conflicts with other resource values (such as the need to protect habitat for desert tortoise);
9.7 percent (1,512,179 acres) were lands removed from wild horse and burro use through court decisions; urban expansion; highway fencing (causing habitat fragmentation); and land withdrawals;
9.6 percent (1,485,068 acres) were lands where no BLM animals were present at the time of the passage of the 1971 Act or places where all animals were claimed as private property. These lands in future land-use plans will be subtracted from the BLM totals as they should never have been designated as lands where herds were found roaming; and
8.0 percent (1,240,894 acres) were lands where a critical habitat component (such as winter range) was missing, making the land unsuitable for wild horse and burro use, or areas that had too few animals to allow for effective management.
(The percentages above were current as of July 25, 2011.)


Myth #5: The BLM is managing wild horse herds to extinction.

Fact: This charge is patently false. The current on-the-range population of wild horses and burros (approximately 49,200) is greater than the number found roaming in 1971 (about 25,300). The BLM is seeking to achieve the appropriate management level of 26,684 wild horses and burros on Western public rangelands, or about 22,500 fewer than the current West-wide population. The BLM also actively monitors the genetics of each herd by sending genetic samples to Dr. Gus Cothran at Texas A&M University. Dr. Cothran furnishes the BLM a report on every sample with recommendations for specific herds.


Myth #6: The BLM removes wild horses to make room for more cattle grazing on public rangelands.

Fact: This claim is totally false. The removal of wild horses and burros from public rangelands is carried out to ensure rangeland health, in accordance with land-use plans that are developed in an open, public process. These land-use plans are the means by which the BLM carries out its core mission, which is to manage the land for multiple uses while protecting the land’s resources. Livestock grazing on BLM-managed land has declined by 35 percent since 1971 (when Congress passed the Wild Free-Roaming Horses and Burros Act) — from 12.1 million Animal Unit Months (AUMs or forage units) to 7.9 million AUMs in 2013.


Myth #7: The BLM lacks the legal authority to gather animals from overpopulated herds or to use helicopters in doing so.

Fact: This assertion is false. Section 1333 of the 1971 Wild Free-Roaming Horses and Burros Act mandates that once the Interior Secretary “determines…on the basis of all information currently available to him, that an overpopulation exists on a given area of the public lands and that action is necessary to remove excess animals, he shall immediately remove excess animals from the range so as to achieve appropriate management levels.” Section 1338 of the law authorizes the BLM’s use of helicopters and motorized vehicles in its management of wild horses and burros.


Myth #8: Gathers of wild horses by helicopter are inhumane.

Fact: This claim is false. The BLM’s helicopter-assisted gathers are conducted humanely, as affirmed by three recent independent reports (see below), and have proven to be more humane, effective, and efficient than other types of gather methods when large numbers of animals need to be removed over wide areas or rugged terrain. Helicopters start the horses moving in the right direction and then back off sometimes one-quarter to one-half mile from the animals to let them travel at their own pace; horses are moved at a more rapid pace when they need to be turned or as they reach the entrance to the capture site. Helicopter pilots are better able to keep mares and foals together than horseback riders; pilots can also more effectively move the animals around such barriers as deep ravines, fences, or roads.

In Fiscal Year 2012, out of 10,350 wild horses and burros gathered, a total of 80 animals, or approximately three-quarters of one percent (0.77 percent), died or were euthanized during gather operations; of those 80, 22 animals, or about one-fifth of one percent (0.21 percent) of the gathered animals, died or were euthanized because of acute injuries. Acute injury deaths include all animals that died or were euthanized because of acute injuries, such as spinal cord or head injuries, fractured limbs, or other severe injuries that occurred during gathers. Total deaths include all animals that died or were euthanized for any reason during gathers, including acute or sudden injuries or illnesses, as well as chronic or pre-existing conditions that required euthanasia (such as limb deformities, lameness, and poor body condition).

Two reports issued in the fall of 2010 (one by four independent, credentialed equine professionals and one by the Interior Department’s Office of Inspector General), plus another report released in 2011 by the American Association of Equine (Veterinary) Practitioners, found — without any ideological or political bias — that the BLM’s gathers of wild horses are conducted in a humane manner. The Inspector General determined that the BLM’s gathers are “justified” and reported that the agency “is doing its best to perform a very difficult job.”


Myth #9: If left alone, wild horses will automatically balance their reproduction rate with rangeland conditions.

Fact: There were an estimated 25,300 wild horses and burros in 1971, and those numbers rose to a peak of more than 60,000 before the BLM was authorized and able to effectively use helicopters for gathers. If left unchecked, Mother Nature would regulate the wild horse and burro population through the classic boom-and-bust cycle, where the population increases dramatically, food becomes scarce, and the population crashes through starvation or dehydration.


Myth #10: The BLM overestimates the number of wild horses and burros on the range.

Fact: This assertion is false. Currently, most BLM field offices in the West use a “direct count” method that involves the counting of each wild horse and burro actually seen during aerial surveys. This method, the Government Accountability Office (in October 2008) and a National Academy of Sciences research committtee (in June 2013) concluded, results in an undercounting of herd populations. A BLM directive, known as an Instruction Memorandum, seeks to correct this undercount by using two principal methods of survey that account for a range of error. The two survey methods, which will be implemented in a multi-step process, are known as “simultaneous double-count” with sightability bias correction and “mark-resight” using photographs. The directive, prompted by the GAO report, can be accessed at this link.


Myth #11: The Government Accountability Office, in a report issued in October 2008, found that the BLM has been mismanaging the Wild Horse and Burro Program.

Fact: This claim is completely false. The GAO made no such finding. The full report can be accessed here: http://www.gao.gov/new.items/d0977.pdf


Myth #12: Wild horses are native to the United States.

Fact: This claim is false. The disappearance of the horse from the Western Hemisphere for 10,000 years supports the position that today’s American wild horses should not be considered “native.” American wild horses are descended from domestic horses, some of which were brought over by European explorers in the late 15th and 16th centuries, plus others that were released or escaped captivity in modern times. Over this 500-year period, these horses (and burros) have adapted successfully to the Western range. Regardless of the debate over whether these animals are native or non-native, the BLM manages horses and burros on public lands according to the provisions of the 1971 Wild Free-Roaming Horses and Burros Act, which describes the animals as “wild” rather than feral.


Myth #13: Two million wild horses roamed the United States in the late 1800s/early 1900s.

Fact: This mythical figure has no historical basis; it is complete speculation. In a book titled The Mustangs (1952) by J. Frank Dobie, the author noted that no scientific estimate of wild horse numbers was made in the 19th century or early 20th century. He went on to write: “All guessed numbers are mournful to history. My own guess is that at no time were there more than a million mustangs in Texas and no more than a million others scattered over the remainder of the West.” (Emphasis added.) Mr. Dobie’s admitted “guess” of no more than two million mustangs has over the years been transformed into an asserted “fact” that two million mustangs actually roamed America in the late 1800s/early 1900s. When it comes to the historical wild horse population, a substantiated and more relevant figure is the number found roaming in 1971, when the BLM was given legal authority to protect and manage wild horses and burros. That number was 17,300 wild horses (plus 8,045 burros), as compared to today’s estimated population of 33,780 wild horses (plus 6,825 burros).


Myth #14: Under the 1971 Wild Free-Roaming Horses and Burros Act, BLM-administered public lands where wild horses and burros were found roaming in 1971 are to be managed “principally but not necessarily exclusively” for the welfare of these animals.

Fact: The law’s language stating that public lands where wild horses and burros were found roaming in 1971 are to be managed “principally but not necessarily exclusively” for the welfare of these animals relates to the Interior Secretary’s power to “designate and maintain specific ranges on public lands as sanctuaries for their protection and preservation” — which are, thus far, the Pryor Mountain Wild Horse Range (in Montana and Wyoming), the Nevada Wild Horse Range (located within the northcentral portion of Nellis Air Force Range), the Little Book Cliffs Wild Horse Range (in Colorado), and the Marietta Wild Burro Range (in Nevada). The “principally but not necessarily exclusively” language applies to specific Wild Horse Ranges, not to Herd Management Areas in general. The Code of Federal Regulations (43 CFR, Subpart 4710.3-2) states: “Herd management areas may also be designated as wild horse or burro ranges to be managed principally, but not necessarily exclusively, for wild horse or burro herds.”


Myth #15: The Code of Federal Regulations (43 CFR) specifies that the BLM is to allocate forage to wild horses and burros in an amount “comparable” to that allocated to wildlife and cattle.

Fact: The Code of Federal Regulations (43 CFR, Subpart 4700.0-6) states that “Wild horses and burros shall be considered comparably with other resource values in the formulation of land use plans.” This regulation means that in its development of land-use plans, the BLM will consider wild horses and burros in a manner similar to the way it treats other resource values (e.g., cultural, historic, wildlife, and scenic, as distinguished from authorized commercial land uses, such as livestock grazing or timber harvesting).


SOURCE: http://www.blm.gov/wo/st/en/prog/whbprogram/history_and_facts/myths_and_facts.html


Wild Horse and Burro Advisory Board Meeting, September 10 (part 4 of 4) last session of the day

16 Sep

Wild Horse and Burro Advisory Board Meeting, September 10, 2013

(part 4 of 4) last session of the day

Many people have sent the BLM Wild Horse and Burro Advisory Board comments prior to this meeting. What follows below is the text I captured from the live-streaming meeting.  If you would like to share the comments you sent in before this meeting took place, please add them to the comments.  I think it helps us all to know what was sent to the advisory board.

Additionally, if you have screen shots from the live-stream or video of the live-stream (I’ve seen some floating around facebook over the last few days), please post a comment below the appropriate session’s blog post with a link to your video or screen shot.

For this last session of the meeting on September 10, I lost all the text I had captured; several of my friends knew what I was doing and sent me the text they had captured. Nancy Canarelli Watson had by far more than any of others who captured text that was  sent to me.  I also want to thank Diane Bozarth and Sonya Malaecky Spaziani and Pam York who tried to help me and sent me captured text from the last session on September 10, 2013

Note to my readers:

   AS I watched the live-stream and the captured text, I noticed various problems with the captioning. It is evident to me that voice recognition software was used to capture the text from the speakers instead of a professional transcriber like a court reporter.

 There are many words here that are not spelled correctly. When trying to read this captured text, and the word is unintelligible, trying saying the word out loud phonetically. I hesitated to change any text or make corrections as I did not want to be accused of modifying it to suit any particular persons benefit or detriment. Please consider this not as an essay, but more as notes and a guide for further conversations.

–  When you see this: >>   it means theres a change of speaker. Sometimes the live-stream captioning added the names of the speakers and sometimes it did not.

–  The multiple dash – means that live captioning dropped some text.

–  Sometimes the live captioning repeated the beginning of a sentence and sometimes whole sentences were dropped.

–  I added double stars  **  when I believe the speaker changed

–  Occasionally, Ive added bracketed text for clarification purposes Continue reading

Wild Horse and Burro Advisory Board Meeting, Sept 10, 2013 Arlington, VA (part 3 of 4 – session right after lunch)

13 Sep

Wild Horse and Burro Advisory Board Meeting

Sept 10, 2013  Arlington, VA

(part 3 of 4 – session right after lunch)

Note to my readers:

AS I watched the live-stream and the captured text, I noticed various problems with the captioning. It is evident to me that voice recognition software was used to capture the text from the speakers instead of a professional transcriber like a court reporter.

There are many words here that are not spelled correctly. When trying to read this captured text, and the word is unintelligible, trying saying the word out loud phonetically. I hesitated to change any text or make corrections as I did not want to be accused of modifying it to suit any particular person’s benefit or detriment. Please consider this not as an essay, but more as notes and a guide for further conversations.

 I should have mentioned this previously:

–  When you see this: >>   it means there’s a change of speaker. Sometimes the live-stream captioning added the names of the speakers and sometimes it did not.  

–  The multiple dash – – means that live captioning dropped some text.

–  Sometimes the live captioning repeated the beginning of a sentence and sometimes whole sentences were dropped.

This text is as it came from the captioning feature on the live-stream; no edits, spell checks or grammar was corrected — no editing except I broke the text into smaller paragraphs to make it more readable.  

>> KATHIE LIBBY: Okay, ladies and gentlemen, we’re going to start in one minute.

>> DR. BOYD SPRATLING: Welcome back. For our afternoon session of the Wild Horse and Burro Advisory Board. Again, this afternoon we’ll be talking about fertility control or fertility management so that’s going to be a rousing and probably generate a lot of he did bait and discussion. We’re looking forward to that. Meantime a couple housekeeping chores.

The public comment period will start time positive at 3:00. Because that’s how it’s listed. So we will make sure that this presentation will be completed and we’ll have a 15-minute break so we’ll be done with this presentation at 25 — we’re done with this presentation at 20 minutes to 3:00. 15-minute break. Back in the room at 5 minutes to 3:00 so everybody can be seated and we start the public comment on time. So with that, I’d like to welcome Dr. Cheryl Saa from the St. Louis zoo and talk about methods and effects of fertility management, chapter 4. Thank you very much.

>> DR. CHERYL ASA: Thank you for inviting me. As others have acknowledged, there were other authors of this chapter, David Powell, David Sane and Dan Rubinstein. So I also want to give them credit for the hard worth they’ve put into this. So I’m just tasked with presenting it to you today. And I haven’t received instructions on how this works. We’ll see. That worked. Okay, got it.

And I decided to start with this just to give you background in my experience with horses and with contraception because I’m always just references coming from the St. Louis zoo and I figured people would wonder what in the world I would have to do with anything like this. But I actually have some credentials that apply. So for my masters in Ph.D. degrees, I worked with horses, with domestic horses and looked at aspects of behavior in University of Wisconsin in Madison and I was one the people in the BLM contract University of Minnesota in the 80s that looked at vasectomy of stallions and of steroid hormone plant treatment of mares in Nevada and south east Oregon. And that was part of a prior NRC report so I had that experience before. But since then I’ve spent the last 25 years at the St. Louis zoo and at the same time I’ve run a contraception program for North American zoos that sanctioned by, say, accrediting pody, professional body association of zoos and aquariums for North America. I was a coauthor, I have a book on wildlife couldn’t accepting that looks at issues, methods and applications.

So I’ve thought about it a lot. And in the last five or so years or maybe it’s getting closer to 10, I’ve been a scientific advisor to the alliance for contraception in cats and dogs. The relevance there is that in zoos we do work with the idea of small populations but we can get access to our animals easily and we’re looking at an individual by individual basis when we choose methods. But for fairly cats and dogs, stray — ferile cats and dogs, stray cats and dogs, there are similarities with the problems you face with horses because you’re not just looking at welfare of the individual animal but at population level changes. And so I’ve had that experience as well.

So fertility control and population management, I wanted to point out — and something that didn’t make it into the report because it didn’t seem relevant at the time but as those of us who are on the committee are giving interviews and talking to folks who are interested since the report came out, I started thinking it would be good to mention there is a parallel universe out there that many of you probably under know of there are a lot of people who for quite a few years for decades have been looking at methods to control other kinds of populations so you’re probably more familiar with work that might have been done with white tailed deer and other species but these are some that might be more familiar. There are people dedicated with looking not just at the kind of methods but looking at population level dynamics depending on the kind of contraceptive or method that’s used. You’re not having to reenvent the wheel. There is other information out there that could be relevant and helpful to you. Okay.

So what I want to start with — and this is a long chapter and when I was first told that I had 90 minutes I thought oh, my God, how am I going to fill that. As I started putting this together and referring to the chapter and we covered, then it was like oh, my God, how am I going to fit it all in.

So I will try to bees as thorough as I can but also hope that I’m not overwhelming you with too much information. This is going to be a delicate balance to strike. But I’m starting with horse basics because first we always have to think about where in the reproductive process that we’re applying fertility control because that will affect the outcome. We were told early on we had input from a number of sources about the sensitivity of not interrupting natural processes more than you have to. Like to preserve natural behavior in social systems in particular because that’s something people can easily observe. But we’re also of course looking at physiological processes and not wanting to cause health problems for animals.

So I’m going to go through this really quickly. I think this is one of the slides I don’t have to spend a lot of time on. But these were the considerations as what we know about horse behavior in the wild that we would reference when we would see well what would the outcome be of a particular contraceptive or a particular method? How would that impact the natural behavior?

So we know that the basic social unit is a harem that has several mares plus a dominant stallion. Sometimes that includes a subordinate stallion. Breeding is seasonal going through spring, late upper, early fall depending on the conditions that year and the location.

And stability of the bands or harems can vary among locations. We looked at a lot of data from different sites. And it’s clear that some degree of natural turnover is natural. And we just paid attention to whether using ferility control might change that.

Stallions unlike most other species that breed seasonally, stallions stay with their harems year round. Most of the time males only bother to be around when males are ready to mate. But in the next quality control and that’s when offspring disperse and that’s around the time of sexual maturity and young males will leave and lead bachelor groups but young females will leave and join other harems. He productive physiology puberty occurs at 18 months for both males and females, variability depending on body condition and sufficient and in domestic horses and breeds with make a difference. In the wild males don’t usually gain access for females and have the ability to mate for several more years.

Mares seem to want miles who are more socially mature. So females will begin to reproduce before the males do. Mares give birth in the spring and followed by a week or so by a post partum estessis and not as fert can conceive at that time. If they don’t, they’ll lactate every three weeks until pregnant again. The interbirth intervals found in the literature and what was published and from interviews with people seems to be about every other year. So they potentially could give birth annually, we’re guessing this may have to do with nutritional status. If they’re not in the sort of prime condition that you would get with a domestic mare that’s kept and fed, that could breed easily annually, that maybe that’s why we don’t see annual reproduction in all the mares that are out free roaming. Fertility rates among domestic mares is quite high. 80-100% for the ones in good condition. The trends are that fertility is lower in young and old mars, that’s typical for most mammals, gestation length in horses 11 months so that means as I said, mares in good condition should be able to produce a foal every year.

That’s the background, now we’re going to dive into the potential methods for controlling fertility so I want to start with what is a real eye important point and is going to determine — really important point and is going to determine the path you take as you absorb this information and deliberate and make decisions. There is no method for preventing production of foals that doesn’t affect some aspects of physiology and behavior. And I think that would be true even if we found something we would call a perfect or a magic bullet, it’s still got to alter something if there’s not going to be a foal. In fact, minimum there won’t be foals and that changes the demography of the band. There are fewer youngsters in that band and in that population.

There inevitably will be differences, the question is are they serious differences or differences we can accept? So general considerations, when you start looking at these methods as do you want to direct it at males or females or maybe both? Are they permanent or reversible? The percentage efficacy? Are you looking for a minimum level of efficacy before you’re going to bother? Side effects that can be acuties just around the time that you’re applying the method or it could be that there are long term side effects and that’s really important to consider. Are they safe. Do they cause problems that are not acceptable and what are the effects on the behavior. The duration of action and of course that’s important for applying in the field if they don’t last very long, they’re not as practical. Reversibility rate long term gives you a way to manage genetic hedge in the population.

Delivery route, this gets to administration. Can you use remote delivery which means darting or are you going to have to capture them and have the animals in hand to do the procedure or to administer the method? And then something that really is important when it gets down to it is the product available? Is there enough of it? Is it commercially available? Can you get to it? Is it a research product or an approved product that you know that you can get reliably? And that really does muddy the waters. And for 25 years I dealt with that problem for the zoo community.

So the methods then adjustment of sex ratio wasn’t something I’d thought of. But that was in our task so we did look at that and discuss it.

So as we understood the way it was described to us, it would mean selective removal of females so that there a disproportionate number of males. Typically any population of mammals is approximately 50/50 naturally. Although that can vary depending on stochastic events and such. But in this case we understood it to mean that there would be excess males. And what we’re worried about is that you already have a polygamous social system and that means one mile mating with multiple females and if you’ve got about 50 mers males and females, that means there are a lot of males that aren’t mating, those are bachelor bands or stallions, most are interested in mating. That means the likelihood of competition and fighting.

So our concern was that if you just allow there to be more and more males out there competing for this limited number of females that you might get an unacceptable level of fighting and injury. This hasn’t been studied as fares we know. If anyone is trying it, we’ve not seen the results. But that was a concern that we had.

Selective sterilization of males. And this is something else that we learned of in that statement of task was to castrate, to — and the method horse asks very common, used a lot.

Gelding. So it’s a common surgery. But we’re also a little less worried about this than the impact to males. But still if you have gelled mails, you’re going to have an excess number of mails out there on the range and competing for resources and not able to compete with intact stallions, so likely to be ostracized. We’re not quite sure what would happen with them. Again, one of these unknowns and we would recommend that before you do that with a control child, see what happens. Would there be chaos socially by having these extra males.

Selective reversible contraception of one gender so this could be males or females and this is what I’m going to cover in much of the rest of the presentation and outcome with depend on the method itself, how it would then affect social interactions or competition.

So starting with female directed methods, permanent sterilization, the committee was concerned about recommending surgical method in the field and we also had been hearing and much of this is just hearsay and there weren’t actual written statements on it. But we also had the impression early on that permanent methods weren’t going to be as acceptable because of concerns about genetics and such. Your advice 0 group is interested perhaps more so in permanent methods. So I’m sorry that we didn’t know about that earlier on. We might have spend more time in the report deal with it. But we might have had concerns about surgery in the field.

Surgery in controlled situation in the barn is one thing. I’ve done vasectomies in the field which isn’t invasive. It just goes through the scrotum. But still it might start raining. Wind blowing and dust and dirt blowing and just keeping surgical clean enough to do a vasectomy was a concern to me.

So a mare where you’re opening the body cavity concerns me much more because I was taught this means it’s a major surgery if it’s centering the body cavity so you’ve got much more of a chance of serious infection. And typically, a mare would be monitored for at least a few days or more following a surgery to look for complications. I don’t know if there are ways perhaps there are ways to bring an animal in to something like this. But in the field, we just believed that it was too risky. But in contrast if you were using a chemical sterilization method rather than needing the specialized services of a vet and such, should be trained to do that. So we were shying away from surgical concerned about complications.

Step two of the — as was in the report, our consideration of these. So surgical ovariectomy is removing the ovaries from the female. So the old-fashioned way to do it was abdominal incision there’s a newer procedure. You’re entering the peritoneal cavity. And so as I said, we — every time we would discuss these and we’d go down the road to what might the complications be. We with were very concerned about the implications of it. But broadly the out comes of ovariectomy would be (technical difficulties) that’s never been reported in the field I don’t know if it’s been noticed or if it’s an artifact of something that goes on with the mares that are being kept.

As far as I know, there are no studies of ovariectomy in the field so we don’t know what the behavior would be like what the social dynamics would be like for mares that showed no sexual behavior. Or would it be irregular kinds of behavior like we can see in some of the domestic mares, we don’t know. I put this in because I’ve had a lot of experience now with this alliance for contraception for cats and dogs. And they’re completely — in fact, they exist because the trap neuter release programs aren’t being effective. So of course it’s effective for the animals that get the surgery but at the population level there are no reports that it’s actually effective at the population level and it’s very labor intensive and relatively expensive. But given the numbers of animals, it’s not reaching a large enough percentage of the population.

And especially when you’re relying on a castrated male. Castrated males drop out of society. They’re not competing for territories or access to females so whoever is left that’s intact is going to step in and fill that void so it has no effect except that one male maybe isn’t going to get in fights now and is going to be healthier and live longer. So the it’s a different species, I acknowledge. But just to sort of raise your awareness that people have been doing this for decades now with feral cats and they’re disenchanted with it and looking much more seriously at other methods.

So reversible methods for females, immunocontraceptives, you’re undoubtedly heard of. Pore sign zone appeal use da vaccines, have been most tested, PZP began being studied in free-ranking horses and domestic horses as well. The earlier version it can be confusing. The earliest one is what wore calling liquid PZP, Zona stat H., it was approved or registered with the E perks A for use in the wild horse populations. Highest efficacy is two injections one month apart although there is some efficacy after one injection, but this 2-injection regimen we recognize is not practical in a field application setting.

But the information that we have available to us says even with one injection, there’s some effect depending on the timing of that injection and if in a subsequent year there’s another injection, then the efficacy rate goes up and you start to see some really infects.

For PZP22 this is produced by the same group of scientists as more recent version and in this, they’ve tried to get around this problem of needing two injections. So they’ve incorporated time release pellets that will then release vaccines at intervals that will basically deliver the booster. So the early testing showed good efficacy through about two years which is why it was named PZP22 for 22 months.

But we’re disappointed to see that in some of the more recent tests that we’re getting data for, that the second year efficacy is considerably lower. So I’ve actually contacted — and I’ll have this slide up in a moment, I’ve contacted John Turner to get some idea why that might be the case. Or something that might be easily corrected.

First, I want to introduce the third PZP formulation to stay that product that’s produced in Canada and the beauty of it is that it requires only a single injection. And there isn’t a lot of published data on this. But when we could find is sometimes in some species it’s effective for up to 10 years, that’s not been documented for horses but has been the case in some other species. It’s not been followed that long in horses is my understanding. We could only find one published study in wild horses and I’ve seen references to ongoing studies but I’ve not seen the final results yet.

But for one published study, it showed that the results showed continued evidence of estrus behavior and other signs of estrogen production indicating follicle growth. There there was some concern about this but no evidence of ovulation that would be needed forfeiterrization. So as I said, there are studies that are under way, is one that’s looking at safety and its use in wild horses and I think that’s being conducted by the University of Oregon. At least that’s what their web page says. The mode of action is that the antibodies that are produced by this vaccine prevent the sperm from blinding to the egg. So the left little diagram shows the natural process of firm binding and the right side is shown by the anti-Zona antibodies depicted by stars. That’s not what they actually look like. But to give you the idea of the sperm then are blocked from attaching to the receptor on the egg that would be necessary for the sperm to enter and fertilize that egg.

The outcomes would be that mares should continue to have es throughs and off torey cycles but with no conception so there should be natural courtship and mating behaviors continuing. Because mares don’t conceive, they undergo more estrous cycles than would be typical. Mows that are fertile would conceive in 1 to 3 cycles and not cycle any more that year. But, if a female is not conceiving she would continue to cycle through the breeding season and it’s a potential problem that we looked at and there are concerns on the other side that would this interrupt band integrity because there’s so much commotion with additional matings and stallions having to defend Marys and might mares lose body condition because they’re being hazarded or have less time to feed if they’re spending all this time courting and mating.

But we knew from the Assateague island already that mares that had been treated over years with PZP were showing evidence of improved body condition. That was some years ago. This he were not losing condition. They were in better condition than untreated mares and in fact, they live longer and there are new age classes being described on Assateague island that were never recorded before in these mars that had been treated because they are in such good body condition. I’ll come back to that idea in a minute.

There’s so much information but the eh caste see if you look at the results are higher when it’s hand injected. When you dart the dart may bounce a little bit and you’ve got an injection but not all of it went in. Also they found over the years that it’s more effective if given in the hip muscle so depending where it would hit the animal’s body, it might not be taken up as effectively.

Unfortunately, PZP22 has to be hand injected at least the way it’s formulated now so there’s sufficient pressure to ensure injection of the pellet. So over all, we when we looked at which methods were promising, we went ahead and acknowledged that for these to be effective you are probably going to have to consider hand injection. But with the caveat that on some HMAs where it’s possible to get up close enough to animals and identify your animals and such ma maybe darting will be practical. So that could be something that was decided on a case-by-case basis.

As the previous slide indicated eh catsy will depend on a proper dose. It depends on the adjuvant use. It helps the immune response build the antibodies so that you have an effect. Treatment protocol can make a difference. The individual differences in the animals genetic factors nutritional status and immune status can affect the amount of immune response that that individual mounts. These same factors will affect the duration of the effect. How long it takes before there’s a reversal.

In addition, it’s been found from these Assateague animals who have been treated maybe that’s somewhere between 10 and 20 years I believe then the number of treatments will be cumulative effect. So the more times you treat, the longer it takes a mare to reverse until finally she probably not going to live long enough to reverse so that it can become permanent, depending on the individual and the number of times treated. That may be a good thing in some cases and actually like the idea and you’ve got a permanently sterile animal others when you’re concerned about genetic integrity of population you might want reversal and that could be a disadvantage.

These results about long-term effects are published for the formulations of the first two formulations of PZ because we don’t have that kind of information on Stavek for horses, there’s just not published yet. There is a potential concern that when a female does reverse what time of the year does she reverse, mid or late season her ovaries become competent and sperm can penetrate, then she might in the subsequent year give birth to a late season foal if the foal doesn’t have enough time to go strong and go into winter depending on how harsh the winter is so that’s going to depend on local conditions. There are plenty of cases recorded where late season foals were born and they survived just fine but we acknowledge that the conditions are harsh, that might be a problem.

But that doesn’t mean that in every subsequent year that female is nowing going to have a late season foal. In subsequent years, it looks like females do return to early season birth, early season estrous so that’s a short-term problem, not long-term problem. Efficacy for liquid PZP is variable because it’s so much situations, like I said, it’s been used for about 30 years. So it’s been used in so many different populations and early change in the formulation there has been a lot of different published data on these results but the efficacy rate now in the recent history looks like it varies around about 90% which is really good.

PZP-22 — and so it’s designed so it releases the pellets then release vaccine at about one month, three months and 12 months post injection. So Dr. Turner has talked with me and said that his information is that the best time to treat would be in the winter. And so that will actually increase the chances of the vaccine is still active towards the two subsequent greeting seasons. So, if you gave it in January for instance, it would only have to be active for about a year and a half to get you through that next greeting season.

So some of the trials showed 85% efficacy in year 2 but as I mentioned before, the more recent results are much lower than that and vary depending on the study.
Okay. There we go.

Variability, as I said talking about Dr. Turner is this a temporary problem do you know what it is that went wrong, he does believe time of year can make a difference, hand injection versus darting that delivery problem you think it gets better eh fast si if it’s inefficacy if injected into the hip and some concern about variability for field preparation this will have to be assembled in the field and things have to be mixed and originally Dr. Turner and his immediate associates did all of that. But as they’ve then turned this over to other people for further studies, he’s a little concerned about maybe inconsistencies in mixing so he’s following up to check on that.

And then as the product has been developed, there have been two different production methods, one is called extrusion and the other cold evaporation so he feels there’s differences in efficacy in that second year depending on this protocol. They’re working frantically to find out why. All of us push on that because we need products effective for a longer period of time. So Stavak may be that product because in other species as I said, it has a long term efficacy.

But the discouraging thing for us for people working with horses (Spay/VAC) there is just that one published trial so we’re not sure how much of extend to horses. In one study it was 100% in year one. Not a large number of animals. But in 83% in years 2-4. So those are encouraging statistics. Like I said, we’re hoping that would hold in other situations, other locations. And with additional studies.

Okay. So side effects of PZP: Early on, the production method incorporated — it wasn’t good, let’s just say it wasn’t good at separating the oocytes, the eggs from the rest of the ovarian tissue. So to the extent there were contaminants of other parts of the ovary in the vaccine, there was a more generalized effect in the animal that received treatment. And so in particular, effects on the ovary that were destroying the ovary and causing infertility and causing inflammatory reactions and such. So they perfected the production methods.

Still, even with the more recent purer studies, there are sometimes some ovarian what we think areor varian effects judging by the symptoms that there might be less regular estrous cycles and even disappearance of cycles during treatment. These effects are less likely to happen with the pure formulations. Again with repeated treatments there’s a cumulative effect of this. So maybe it’s because of contaminants. We’re not sure. It’s been difficult to study but that mares can become permanently infertile if they’re treated enough times.

Injection site reactions have always been a concern with any kind of vaccine. This is even vaccines that you get, vaccinations. You get a tetanus shot your arm swells up and is sore for a couple days. So depending on what’s in that product, there can be a localized effect at injection site. And early on, the adjuvant that is most effective in helping a vaccine cause the animal’s emunisys testimony to mount in a response, to so be really effective, Frend’s complete adjuvant is good athe that but it’s going to cause injection-site reactions, so this is liquid PZP and PZP-22.

You he they now use Freund’s modified and also reactions are less likely to occur if the injection is given in the hip than in other part of the body. We don’t know why. Other features of PZP vaccines that can be important is that they can be given safely during pregnancy, they can be given safely during lactation, they can be given before puberty, this is not true for some of the other products

. Concern about immune response, there is a hypothesis that mares that don’t respond to the vaccine will be reproducing, if this is genetic trait, then this resistance could be passioned on to the youngsters and you could up with youngsters. You’d have to find a new method. But there are data that are accumulating from the — you know, the years and years of trials on Assateague island and Shackleford banks. And there is so far no evidence that this is happening. No evidence of resistance. So we think this is probably not a real concern. But something that you know, people will keep their eye out another potentially more serious concern is that it might involve more immune functions and might involve the animal that’s been treated more susceptible to particular pathogens so that would depend on what pathogens that it would be facing.

But, again, after all these years of treatment, this has not seemed to be a problem. No effects have been noted. But when you’re working with different populations, it’s something you should be cognizant of and watch for. Positive effects. Those were the potentially bad effects. Mares treated with PZP vaccines on Assateague are in better body condition and leaving live longer and that’s because they don’t have to face these really heavy energetic demands of pregnancy and lactation.

And I teach classes and I have to start out every semester talking to students about we live in a society where our problem is there’s too much food available of really concentrated nutrition and calories. We’re really focused on thinking about taking in less so that we don’t become overweight.

Animals in the wild have the opposite problem. They’re always at this sort of energetic interface with starvation. So they’re having to search for food and especially for the kinds of populations we’re talking about in the western U.S. and the droughts that are going on now. That it’s really hard on a mare to go through gestation and lactation. That takes an awful lot of energy. And so I would predict the effects would be more profound in the west than they are on Assateague and on Shackleford where the food sources are a little more reliable.

During the time the committee was meeting to produce the report, the data came in on Shackleford and they’re finding exactly the same thing. Mares in better body condition. It’s not been long enough yet to show additional age classes but we wouldn’t be surprised if that happens.

Long-term population effects. Beyond the target numbers of animals to treat and percentage of efficacy that I already talked about, now that we know that mares are going to live longer that’s go to have to be factored into the calculations. When you do this modeling and I don’t know if any of you personally have had this experience about providing data for computer modelers that do population projections but you start with basic life history information. Age of puberty, number of offspring produced per year and such. But reproductive life span may be longer in mares that, say, are treated, 4, 5 years or so and then allowed to reverse, maybe they’re going to be producing up until 25 years of age instead of 20 years of age or something like that. We don’t know. But it’s something to take into consideration when you’re modeling these populations. The number of treatments though, the longer — the longer they’re treated, that may make them infertile. Maybe these factors are going to balance each other, but I want to put a plug in here for considering these and doing modeling and you’re making your decisions about which methods to use.

Concern about Spay/VAC, a separate one that we’ve heard and we don’t have an answer for yet that uterinae deem awas reported was that the endometrium of the uterus was more swollen and more enfused with blood. And that can be a normal part of the estrous cycle that it would happen during estrous and then it regresses. So in a normally cycling mare you might see that in a transitory way and then it would be gone. The question for the Spay/VAC treated animals is whether that would be chronic and if it was chronic, would it predispose that female to infections and other types of problems. These questions have been posed to the people doing the Spay/VAC research so we hope that they’re gathering that information for us. So that’s it with PZP.

Moving on to another kind of vaccine that is much more recent and has been only approved of this year for horses, gonado trope inreleasing hormone so an endocrine lesson here. The hypothalamus produces GnRH which travels to the pituitary gland and it stimulates the release of two other home own and known as luteinizing hormone and follicle stimulating hormone. LH and FSH, they go into the bloodstream and in females will stimulate ovaries and males testes. The level of the pituitary is exactly the sameor moans, it only changes once we reach the gonads. So blocking GnRH or blocking its action will stop the reproductive process entirely.  So these hormones as I said, are in both males and females. So this product could be effective in either gender.

The product that’s now been licensed is gono come. Vaccine against GnRH. GonaCon. It’s out of Fort Collins and there’s not much horse data for horses, first approved white tailed deer. Less about its use in horses, it can be delivered by dart, which is an advantage. There are other GnRH vaccine products on the market in other countries, in fact, there’s one in Australia called equity that is used specifically in horses. So there are some data about GnRH vaccines but they’ve never been used as far as we know in free ranging populations. But we expect that the effects would be fairly similar. Soot least in looking at action and physiology and side effects, we can also draw on those.

Here’s a diagram from the report. This shows GnRH diffuses from a membrane into a pituitary gland and LH and FSH go on. We’re showing the ovary so the ovary secretes estrogen and subsequently progesterone is part of the natural ovulatory cycle. When there’s contraception with the GnRH vaccine, then that vaccine can’t enter the pituitary to have its effect on stimulating LH and FSH released so you don’t get stimulation of the ovary. So in some ways it’s similar to a chemical ovariectomy because you’re then blocking the effect or the release of the ovarian hormones.

The two horse studies that we could find published were one from penned mares and one in free ranging, eh fast see was high in year one and decreased gradually over next several years. Higher in penned study but different methods of measuring which was a compound in measuring results. The conjecture was that mares might have not mount the as strong an immune response because of their health. The out comes from the field study is no effects on behavior seen.

Social interactions or in band integrity. They seem perfectly normal. That doesn’t seem right. This should be similar to an ovariectomy my. There were continued signs of estrous in the treated animals. That suggests, indicates, incomplete expression estrogen production, but there was complete contraception. So back to an endocrine lesson again. Even though that figure and what I told you was that GnRH stimulates LH and FSH, it does. But FSH has a mind of its own. What we think is happening is that FSH — enough FSH is being produced but it stimulates the follicles to begin growing, HL only comes along in a surge to finalize that follicular growth and to cause release of the egg at the point of ovulation. So FSH will cause follicle brother and no ovulation and that makes sense given what we know about pituitary control of FSH and what we know about control of ovulation.

At first we were going to dismiss any of the production because it’s going to wipe out gonads or behavior but in this case with FSH still stimulating the ovaries and we think we really hope they’re doing more studies that might confirm this. To the extent that es trademark clearinghouse behavior is maintained there’s normal behavior happening in the field so that’s why this product made it on to the final list. I mentioned it could be used in males or females so why don’t we also use it in males.

The system — males are different. Also the way FSH facts in males is different. It’s only needed to generate in males. This happens in continual breeders at puberty but in seasonal breeders it happens every year at the beginning of the breeding season but it’s LH that does everything else. LH is what stimulates testosterone production and that supports spermatogenesis. So without LH, you don’t get testosterone or sperm. So neither of the features of mailness, the testosterone to support the behavior or fertility. This is meaningless when it comes to the out comes we’d be looking for.

Okay, another kind of GnRH product. This is called an agonist. That’s just a chemically synthetic form of a hormone that had similar action to the native chemical. So in this case it acts like GnRH itself. Which seems counter intuitive that this could be used for a contracept but it’s because of the unique way the endocrine system controls itself, I guess you could say. The GnRH vaccine blocks the action of GnRH. Whereas, a GnRH agonist will start, it has an initial action of stimulating the whole reproductive system and in fact in some formulations, in fact there was a product called ovuplant for horses and it has a GnRH in it and that GnRH agonist will stimulate es Joan ovulation for timed artificial insemination but it’s in this implant that releases the contact for a few days, bolus causes that surge. When its use was a contraceptive, it’s a continual release in a long release or slow release implant that were released from 6-12 months.

Two different formulations on the market now. That works by negative feedback so you first get an effect of the products will feedback on the brain and shut down further production. So after initial stimulation you get negative feedback and all reproductive hormones are shut down. We use it in zoos very could only as a contraceptive and we have various mechanisms to deal with that first stimulation phase. The commercial product of this that’s available right now is (indiscernible) and fast acting are used for inducing estrous and ovulation.

Seprelorin some mares seem to be responding to down regulation phase so it’s possible the slow release form could be effective. But our concern is that on the effect of the ovaries. So Suprelorin is listed right now in the U.S. as a new ADA category. It’s for use only in ferrets and there’s a disease condition for ferrets that it’s useful for. Other wise only research product for other species. There’s no apparent advantage of it over the GnRH vaccine so we didn’t take it as seriously. Because the GnRH vaccine would do what it can do and we know it that the GnRH vaccine would allow that estrous behavior to continue.

I’m going to go over steroid hormones quickly. This is research that came out of one of the earlier recommendations from an earlier NRC committee. And was reported on in their report in 1981, I believe it was. And so there are several reasons which I’ll mention why this is not leekly to be approved today.

So estrogen and progestins are the hormones and so these are synthetic versions, this is human birth control pill. Synthetic versions of these hormones are more bio active and less subject to metabolism to breakdowns so they stay in the system longer and they can have an action over a longer period of time. There’s only one synthetic progestin of oh, gosh, only one in horses, they can be incorporated to have long lasting infects. We use these in zoos aa lot. The minimum effective life of these implants is two years. With you the problems is that steroids are lib id soluble. They dissolve in fat which means they accumulate in fat tissue in the body and they can then enter the food chain. So FDA absolutely does not like the idea of those being used in free ranging animals. I think it’s very unlikely without major attitude change in FDA that these would ever be approved for use in free ranging animals. Since we don’t have a lot of time, I’m going to skip through this.

Because I don’t think it’s possible to use them and they are covered in the report for anyone who’s interested in looking at the details. So let’s see. In the studies done they found — this might be an important point to bring up. They put implants in the neck and they tended to fall out. My enexperience of using implants of any kind in horses is that they seem to be rejected. Clean implants there’s something that they don’t like implants in the skin. They put them in the peritoneal cavity and those were successful in not the progesterone but when it was combined wees Jen they were successful. But they’re entering the peritoneal cavity which makes it a little more risky. It’s only then a tiny little incision that you’re trying to use. Not a full surgery but still you’re opening up the peritoneal cavity. Like I said, I’m going to skip through this.

IUDs there are two studies with horses that we could find. And the one that used on the market that are already for humans fell out not surprising. Horses in women are different size but the custom — there was another study that had custom made IUDs that were the correct site and they were effective and didn’t follow out. They were subsequently removed after the study was over. There was uterine inflammation during treatment that reversed following it treatment. So this doesn’t seem to be serious side effects. But there is no known source of IUDs for horses even though that might seem trivial. We’ve done studies and thought God, this would be a perfect contraceptive, we can’t find a company to make it. And then regulatory issues involved. And so this is something that might actually work but you’d have to find somebody who was going to shepherd it, who was going to actually agree to produce it in the good manufacturing practices methods which again is a real hurdle to get through. And that would — you know, make it available and do the trials and such. So I think hypothetically, this is a good option. But it’s right now it’s not practical because there are no production to try.

Permanent methods for males, surgical or chemical castration, we know lots about surgical castration because of the history of gelding. But there is a product on the market for chemical sterilization, that’s injected into the body of the testes and it causes the generation of the seminiferous tubules. So those are the tubules where Asperger’s are — where sperm develop. But it’s the data that have come out so far and it’s being used primarily in domestic stray dogs is that there seems to be testosterone remaining. It’s questionable how much and which mails. But to the extent there’s still testosterone made, you might get normal male type behavior but there’s been no comparablex ed ity in horses. The testes of a horse is much bigger than the testes of a dog.

>> Efficacy but it is sought comes of surgical castration is very effective of course in eliminating fertility, for those treated males but because it’s also likely to severely reduce male typical behavior those mails aren’t successfully completing with intact males, the intact mails are going to all this is true for most animals though there are species differences that a male’s sexual experience before castration will affect behavior afterwards so there are learned castration but that’s not predict. Persist but it’s still not guaranteed. So, if you — if these males are not successfully competing in sequestering mares, it’s not going to be effective. Out comes of chemical castrations we don’t know what the effectiveness would be of horses, it’s effectiveness is high in dogs but in early childhood it’s invariable as they’re working out dosage and protocol.

Not possible to predict the effect on behavior well enough yet. Males continued but looking at vasectomy and the reason we like vasectomy better is because it preserves male behavior so it gets rid of the sperm that would cause for tilt but it preserves behavior and I’ve heard although again no publications I’ve heard there are a couple people would are trying chemical vast entering in Val numb. I’ve heard no results yet. There are published data for domestic dogs and cats and using this and actually data out of Iowa State University didn’t catch on because if you think about it, most people agree to castrate their pet dog or cat not so it won’t impregnant knit the neighbor’s animal.

Unwanted behavior fertility and not affect the behavior. But it’s being used here and there. Here in the wildlife control studies. So we think actually has a lot of promise but it would need to be tested in valium in what kind of dose you needed. There are a number of different chemicals audience it should not be painful. There aren’t pain endings the epididymis where you put this. There aren’t pain endings inside the testes where you put the chemicals to cause the chemical castrations. So, if the protocol is followed properly and the injection doesn’t start, the chemical isn’t injected in the the needle is in the proper location there is no pain except maybe transient swelling that may occur over the next day or two.

This is being used regularly now for the past several years in domestic dogs and a lot of up close and personal examinations and if it’s done properly, there’s little or no — out comes of vasectomy we like this because if performed correctly it’s 100% effective so there’s lag time. You have to decide the time of year to do it as with human vasectomy there’s about six weeks there might still be viable sperm in the tract that has to be ejaculated or eliminated somehow because they might still achieve a fertilization. I’ve gotten calls from a lot of places where a vet who had never done a vasectomy thought this was straightforward cut the nerve cord enstead of the vas and the male is still fertile so you have to look very carefully and make sure you’re cutting the right thing.

The other thing reported in the literature, not very common but it can happen, you need to remove a section, you need to cauterize or tie off or exteriorize one end because if you just make a cut, then when the animal stands up again and the cord is extended it forms a canal that heals and you have reanastomoses and you’ve got fertility again. So it is important that you do the procedure properly so it remains — doesn’t canalize. Incorrect injection of chemical agent it needs to get into the lumin of the epididymis so there’s a tube that winds its way through the epididymis, a single tube and you need to get inside the lumen and it causes local scarring so sperm can’t pass. So just being careful not to inject it around the scrotal tissue. Out comes low effect of behavior.

I did the behavioral follow-up with vasectomized stallions in the study 25 years ago. The Maries in the harem es treated by stallions didn’t conceive. The caveat is because these Maries aren’t conceiving they go through consecutive cycles and about 25% the bands where I was working late in the breeding season some were finally successful. Of course, can this would not being practical management. I asked at the time why we weren’t using this procedure on all the males we with are getting our hands on and we were told that because this is one of those request for proposal situations, the study had been designed and we just agreed to carry out that study. They’re successful in protecting mares, they are. I published the result from that review is dominance effective and it is.

And as a management strategy it would be a crazy thing to do because you’re leaving all these fertile males can easy being says to Marys, so, if you captured a band and there was more than one stallion by all means you would treat all the stallions in that band and you’d be sure the midwest and east r mares wouldn’t conceive. There’s some movement. It’s just natural so, if you’re looking at foal production. If there’s a new mare in the band that came from intact stallion hair im, they may have a foal. If any of these mares are going anywhere else, it’s going to balance out because these vast enteringectomy mised males aren’t getting mar r mares fertile. There was early on a study with high dose testosterone that was effective in 25% of the stallions and they didn’t report physiological data but they didn’t collect such data as far as we’re aware.

We know from a lot of other studies and species that in general high-dose antigen is associated with heart and circulatory problems and with increased aggression and this used to come from lab animal studies, now it’s coming from humans using androgens for body building and to support athletic prow and such. So we’re seeing this in the data for humans now. It’s not a good thing. And also as for the mares, it’s a steroid method. FDA or EPA aren’t going to approve this. GnRH you’ve got to suppress testosterone. To the extent you’d be — you’ve got to run the chance he’s making enough sperm to get females pregnant. We don’t think it would be effective.

GnRH agonist the same kind of thing. You’ve got to completely block testosterone if you want to make sure you’re contracepted and that’s going to eliminate male typical behavior just a couple additional factors to consider. This extending the breeding season, I’ve mentioned this a couple times. So any of the methods that allow methodss continuing to cycle, and if stallions are maintaining their lib I’d 0 while prehe’d 0 while preventing these pregnancies bees you have ooh you have the possibility they’re extending extra energy. Are they getting enough to eat.

I think I have another slide. Yes, implications. So estrous cycle is every three weeks, estrous lasts almost a week in mares, so that’s a lot of time then if you’ve got multiple mares in a harem. Mares weren’t synchronized. If you’ve got multiple mares in that group, stallions are spending an awful lot of time guarding, hoarding, mating, maybe he’s enjoying that but he’s not eating as much while he’s doing that. Basically looked at that in the vasectomy study I was on and we saw no effect on males. Their body condition was just fine going into winter and they were just fine coming out the other end. But that was a typical year. If it was a bad year, this might put stallions at a disadvantage going into the winter if they hadn’t had enough time to grays graze. How did we identify the methods you’ve surely seen?

The criteria we used were is it effective, of course. The duration of that effect is the availability as I said. Delivery method and from the side effects. Both safety and would it preserve the behavioral systems. And so the methods that met the most crucial were criteria was PZP product. And Spay/VAC although liquid PZTP, it’s available now and the down side it’s only effective for a year. So we really are hoping they’ll be better development of the other two and that they can be used instead and then GonaCon is something that we think also deserves a further look. Male directed chemical vasectomy as I said was the one that rows to the top as preserving, having a few side effects and preserving most natural behaviors.

So I’m not going to read through these tables for you because they’re in the report. I just copied them from the report to just sum up for you. But what we did was just look, what are the advantages and disadvantages of each one based on the information that we were given. Given that I don’t have a lot of time, I’m not going to read this to you and they’re in the report at the end of our chapter.

Summary for GonaCon as well. We looked alt behavior and various aspects of behavior and whether the method would clog the change and whether there was any information in some places we just have to say that no change was reported and we’re not sure how carefully they looked for it. And then back to this initial caveat. None of these methods is a magic bullet. But there is no magic bullet for any species out there yet. You’re not alone. That doesn’t mean you should give up.

We think that all of them would be better applied in a gather even though in some cases you can dart the liquid products in some HMAs where you can get to animals, you can get up close enough to deliver a dart properly, but it might be necessary to just consider making this part of the gather protocol certainly BLM and its contractors know how to do gathers, liquid PZP can be used now although its efficacy is not high — back up a second.

What I’ve said here, if you just give the one injection you’ve captured it, give the one injection, you’re not going to have high eh caste he ooh that efficacy of what we been cowled is that in subsequent years when that animal is treated again efficacy goes up. PZP-22 unfortunately it needs more development. We were hoping it would be closer to the point of being ready. But a recent setback has changed that. Spay/VAC and GonaCon are both really prom but there are just so few data right now for horse that’s we have to recommend there be more studies or at least that the studies that are ongoing, that those get published and that it might not be us but that you folks have those then to use to June. And then chemical vast should be pretty straightforward but it needs — vasectomy but it needs validating in stallions, it’s a new species that you should know in a controlled setting what any of the side effects or problems are before you try to apply it in the fieAnd that’s the end. So I have no idea if we have some time for questions. I will answer them as best I can.

>> DR. BOYD SPRATLING: We have 10 minutes for questions. Dr. Bray.

>> ROBERT BRAY: On the IUD, O ring, how big is that.

>> DR. CHERYL ASA: I don’t recall that they gave the dimensions but they may have. I don’t remember.

>> ROBERT BRAY: From the results of the study they say it wasn’t expelled at all? So given what the parameters of how cervix is made up and during estrous, would it be size of the palm of your hand would be your best guess? Would it be that large?

>> DR. CHERYL ASA: Possibly. We all have different sized hands. I really don’t know. But we should be able to find out and just —

>> DR. CHERYL ASA: Because I brought this up in a.

>> ROBERT BRAY: I brought this up in a research meeting in Denver and follow through on it that made sense. And I asked had there been any studies because my masters reproductive physiology. I met Dr. Genetic managementer in fact back in mying — ginter in my younger years Ph.D. nutrition. And I remember the issues with IUDs and mares but the second study showed that because it was too small and they were expelled during typical investors. So from a practical aspect if we could identify someone to make this flexible IUD, not it evasive. Not a —

>> DR. CHERYL ASA: It’s a little bit invasive because you need to use really clean techniques because you’re going into the uterus which si a fertile environment.

>> ROBERT BRAY: We’re not doing lackotomy. The it’s relative to what what we do to mares, same protocol. So, if we could secure that type of IUD, — if the mare continues to add her behavior, her social interaction she might get bred multiple times. But the question would be in that study did they breed the mares through natural cover or did we know through the actual cover process whether when the male dismounts creates some type of —

>> They didn’t mention that.

>> Whether that would help create more —

>> That suction, no.

>> ROBERT BRAY: When you said full bloom, blossom, he could pull that IUD out. So that IUD was not anchored to your knowledge.

>> DR. CHERYL ASA: As far as I know it was inserted through the cervix. They claim, I don’t remember right now how many mares but it was a pen study. It wasn’t a huge population but they claim that none of them fell out and they claim that you know, they had stallion access to determine that they actually were effective in preventing fertilization. And so I take that to men that they weren’t coming out following copulation.

>> ROBERT BRAY: So from your scientific perspective, if we could design a study such as that that did not have to be with domestic horses in a pen study and we had the method of capturing the animals, inserting the IUD in the mares, monitoring them and actually doing a field study, practical from your perspective?

>> DR. CHERYL ASA: Okay, I have to — as a scientist.

>> ROBERT BRAY: We’re on that same page but I want the practical aspect.

>> DR. CHERYL ASA: I know, but there are lots of penned mare mares, already. I what want to be sure they didn’t fall out and I’d want some follow-up to make sure you didn’t have infection. And that.

>> ROBERT GARROTT: The concept of IUD working.

>> DR. CHERYL ASA: There’sen flam torey response during but that’s not infection.

>> ROBERT BRAY: Which increases the egg to travel faster.

>> DR. CHERYL ASA: And would entfiscal year with implantation, the whole thing. I would want them taken out and see how the uterus recovers and if fertility then ensues. I think ideally I’d be more comfortable with if the aleast at least a pen study. I don’t know that we have time right now to do the details of such a study. I think you would miss them. If things didn’t go well, you wouldn’t know why. You’d need to know if you lost them. If you got pregnancies, they weren’t effect I or was it they were lost? Because — I think you’re right. This study was done a long time ago. I don’t know if you’d get exactly that same one and be following up on that pen study. You’d be starting from zero but you need —

>> ROBERT BRAY: Could you help me with that information? Would you be so kind. I’ll give you a card later on. Thank you, very well done.

>> TIM HARVEY: Dr. Saa, I have a question, I assumed that Spay/VAC was Spay/VAC and all these preparations were an individual product. I’d like from your study we’re seeing different preparations, (Boyd) Spay/VAC is aqueous. And some it’s in ad just ant that may break down the actual liposome that makes Spay/VAC work. How do we extrapolate information from one of those Spay/VAC studies to another? Because it appears now that some of these most recently being brought forward, we’re getting pretty disappointing results that previously had been validated. Where are we at?

>> DR. CHERYL ASA: You’re feel our pain because that’s when we went through in trying to make sense of and summarize the available information and it’s not really a criticism because any time a — I mean it’s a criticism from the point of view of wouldn’t it be nice if it was straight toward and it was a product that wasn’t available and worked perfectly. But when something is developed it’s going to go through iterations if they’re trying to improve it. If something doesn’t work well, they’re going to try something else. So I think for us we have to look at the most recent results because that means they’re discarding the earlier protocols or the earlier products as being not as good as what they’re trying now. There was something wrong and now they’re trying to improve it. That’s why with Spay/VAC, all the PZPs have been through so many different kinds of tweakings that all of them need some kind of extrax ed ity, I mean they’re not ready to go.

>> DR. BOYD SPRATLING: I think that brings the frustration aspect.

>> DR. CHERYL ASA: For us too.

>> DR. BOYD SPRATLING: The view forward is we’re going to have more manipulation of fertility as opposed to actual removals. I I think we all agree that long-term planning is probably not sustainable. I’m frustrated.

>> As were we. I think the liquid PZP is worth using and I think perhaps looking at it as an interim product while the others are, we hope, improving and maybe this is a point where I could eltorial eyes and this wasn’t something we put in the report. But my personal concern and having worked in this area for a long time and watched this development of these products is they’ve never been well funded and I can’t help but think that was it 30 years ago when the last report said you know, fertility control is something BLM should try. And the problem at the time is there really wasn’t a good product that was ready to go that was shovel ready as we say now.
But, if money had been put in it then for research and development, where would we be now?

So, if just say today, there’s not something that really works like we need to to work so we’re not going to bother, who’s going to step up and fund that work so that you do then have a product? And people are working on perfect ducts for other species, other species have different needs and there are different circumstances. There are different physiological processes, different behavioral systems. They may not be producing the product that’s going to be I’d ed y’all for you so you like the horse — the people who are managing horses. So I really think it behooves your group to think about how to support the research and development of these products so they become what you need rather than just be frustrated that they are not today what you need?

That’s not neglecting the committee and report. That’s me with my decades in working with contraception and being frustrated and trying to again funding and get something with potential but, if nobody is there with the money, it’s not going to happen. And you could look to the alliance for accepting of cats and dogs. They have an incredible model of farm suit communities. The shelter community, animal welfare community and reproductive physiologists and veterinarians and funding actions and they have a meeting every two 0 three years and they bring people together and they brainstorm and there’s a wonderful man, Dr. Michaelson in Los Angeles who has put up like $25 million as a prize for the product that’s going to do this for cats and dogs.

>> How much?

>> DR. CHERYL ASA: 25 million and he has made $50 million available for research toward that product. And it means that scientists around the country who used to work on enhanced reproduction are now working on contraception. And so money will drive the research. Scientists are happy to do that if they’ve got funding to do it. So it doesn’t work to just sit on your panel and be frustrated although I feel your pain. But to get more actively involved in the community that’s working toward research and development of contraceptives is where I think your answer lies.

>> DR. BOYD SPRATLING: Thank you very. The my timekeeper is really dancing around. We appreciate very much your coming and giving us this information. We’re going to have to shut it down at that. We’ll take a 12 minute break and be back here at — thank you Dr. Asa.
(ApWe’ll take a 12 minute break and be back here just before 3:00 so we can start on time

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