Done with the diversion

PM IA GAIA #8402 Carson July 2016

Pesticide PZP, promoted for birth control, has caused the divide, subterfuge, diversion, attacks and hate while at the same time revealing its connection to money, greed and politics. People are fooled. . . zealotry develops. . .hate mobs flourish. . . Wild horses suffer.

Focusing on a pesticide for birth control of a native species–that’s already being managed to extinction–is nuts.

What happened to “Stop the Roundups”? PZP doesn’t stop roundups. There are more wild horses being rounded up every year. PZP doesn’t stop slaughter either. The number of horses crossing the boarders to slaughter has increased.  PZP, made from slaughterhouse pig ovaries messes with native wild horses’ immune systems–that’s why it’s called an “immunocontraceptive’. Those pushing the pesticide call it as a “vaccine” for population control.

The fact that there are hardly any more wild horses left in the United States is ignored.

The fact that overkill is ruining the thriving natural ecological balance is ignored.

The fact that cattle and sheep are being poorly managed on public land and causing range damage is ignored.

Big mouths are scapegoating wild horses for range damage by sheep that’s wrecked havoc on the land years ago. Meanwhile America’s last wild horses endure living on public land that’s been ruined by livestock years ago.

We’ve done our part to educate people about PZP in the PZP Forum I created about 2 years ago. If people and organizations want to stick their head in the sand and ignore scientific facts about the many dangers of PZP (see the button above on then they need to be held accountable when the wild herds are destroyed.

We aren’t working on PZP education anymore. That’s done.

Our focus in this movement is on helping to protect and save all the WILD horses we can save at this dire time in history. Please contact me by email if you want to adopt mustangs, purchase 3-Strikes wild horses, start a local network for saving wild horses or start a sanctuary of any size.

America’s wild horses need a huge herd of miracle workers to prevent their extinction at this point in history. You can make a difference now.

Many blessings,
Anne Novak

Founder and Director

Protect Mustangs and the American Wild Horse Institute

Protect Mustangs is a 501(c)3 nonprofit organization dedicated to the protection and preservation of native and wild horses.

Groups who want Pesticide PZP used on America’s last wild horses


According to a press release by Return to Freedom Sanctuary, who seems to have received money from the BLM in the past, the following groups want to use PZP on wild horses:

Alliance of Wild Horse Advocates

American Society for the Prevention of Cruelty to Animals

American Wild Horse Preservation Campaign

Animal Legal Defense Fund

Animals Voice

Animal Welfare Institute

Black Hills Wild Horse Sanctuary

Center for Animal Protection and Education

Citizens Against Equine Slaughter

The Cloud Foundation

Corolla Wild Horse Fund

Friends of a Legacy

Front Range Equine Rescue

Habitat for Horses

Hidden Valley Wild Horse Protection Fund

Horses for Life Foundation

Humane Society of the United States

Jicarilla Mustang Heritage Alliance

Least Resistance Training Concepts

Lifesavers Wild Horse Rescue

Montgomery Creek Ranch

National Mustang Association, Colorado Chapter

Oregon Wild Horse & Burro Association

Photographers for the Preservation of Wild Horses and Burros

Pine Nut Wild Horse Advocates

Respect 4 Horses

Return to Freedom Wild Horse Sanctuary and Preservation

Salt River Wild Horse Management Group

Serengeti Foundation

Southern Sun Farm Sanctuary

Steadfast Steeds

Virginia Range Wildlife Protection Association

Wild Equid League (Colorado)

Wild Horses of America Foundation

Wild Horse Connection

Wild Horse Education

Wild Horse Observers Association

Wild Horse Preservation League

Pm PZP Darts


PZP = Slow Extinction


Don’t let yourself be fear mongered. Read the Science Against PZP:

The Fact Sheet on PZP:

PZP is Dangerous:


PM No Evidence Overpopulation

Protect Mustangs is an organization who protects and preserves native and wild horses.

#Pesticide PZP is dangerous for the last American herds of wild horses and burros

PM PZP Injection

The old hypothesis — that PZP merely blocks sperm attachment — has been disproved.

Kaur & Prabha (2014) found that the infertility brought on by PZP is ” … a consequence of ovarian dystrophy rather than inhibition of sperm-oocyte interaction.” They reported that PZP’s antibodies induce ovarian dystrophy, oophoritis (inflammation of the ovaries), destruction of oocytes in all growing follicles, and depletion of resting follicles.

Despite all the hype about PZP being non-hormonal, the manufacturer himself knew that it had an adverse hormonal effect — significantly-lowered estrogen. In 1992, he reported that ” … three consecutive years of PZP treatment may interfere with normal ovarian function as shown by markedly depressed oestrogen secretion.” Thus, PZP is an endocrine disruptor.

Worse yet, Sacco et al. (1981) found that PZP antibodies are transferred from mother to young via the placenta and milk. The transferred antibodies cross-react with and bind to the zonae pellucidae of female offspring. This is bad news because BLM regularly administers PZP to pregnant and lactating mares, who transfer the destructive antibodies to their filly-foals. Thus, the fillies get their first treatment with PZP in utero, while nursing, or both.

Nettles (1997) found an association between PZP and stillbirths. In 2015, the International Society for the Protection of Mustangs and Burros reported that 7 mares previously treated with PZP, when taken off it, were able to get pregnant. However, 6 of those 7 mares — that is, 86 percent — produced foals that were stillborn. All other ISPMB mares that had not been previously injected with PZP successfully birthed healthy foals. Environmental and other conditions were identical. The only variable was PZP. Meanwhile, over on the East Coast, the Corolla herd, long-managed with PZP, has recently experienced birth defects among its newborns.

Gray & Cameron (2010) questioned the supposed benefit of PZP-sterilized mares living much longer than their normal life expectancy, and and Knight & Rubenstein (2014) warned of unintended consequences of PZP’s ironic effect of extended longevity. Ultra-elderly mares take up scarce slots within AML-restricted herds. They consume resources but no longer contribute to the gene-pool. It is detrimental to a population’s genetic viability to carry significant numbers of sterile herd-members way-beyond their normal life-span. Meanwhile, those few foals that are born have to be removed to achieve AML because they’re more adoptable.

Ransom et al. (2013) conducted a longitudinal study of three herds currently being managed by PZP — Little Book Cliffs, McCullough Peaks, and Pryor Mountain. They found that the the birthing season lasted 341 days — nearly year-round — which puts the life of mares and foals in jeopardy. Nature designed the equine birthing-season to occur in Spring, not year-round, and certainly not in the dead of Winter.

Ransom et al. also found that, after suspension of PZP, there was a delay lasting 411.3 days (1.13 years) per each year-of-treatment before mares recovered their fertility. They warned: “Humans are increasingly attempting to manage the planet’s wildlife and habitats with new tools that are often not fully understood. The transient nature of the immunocontraceptive PZP can manifest into extraordinary persistence of infertility with repeated vaccinations, and ultimately can alter birth phenology in horses. This persistence may be of benefit for managing overabundant wildlife, but also suggests caution for use in small refugia or breeding facilities maintained for repatriation of rare species.”

PZP’s manufacturer conceded that it could take up to eight years to recover fertility after just three consecutive PZP treatments.

The study on PZP by Knight & Rubenstein (2014) found that ” … three or more consecutive years of treatment or administration of the first dose before sexual maturity may have triggered infertility in some mares.” These findings are particularly troubling. They suggest that, actually, only two consecutive PZP-treatments may be reversible. Except, that is, in the case of fillies who have not yet reached puberty — they could be sterilized by just one injection.

PZP’s manufacturer was quoted describing PZP as “so safe it is boring.” Independent research shows otherwise — that PZP is a powerful hormone disruptor that could sterilize a female with just one injection. If staff and volunteers believe that PZP is boringly safe, they will be less likely to protect themselves adequately from this dangerous pesticide. Indeed, many of the volunteers are women and, therefore, at risk. Accidental self-injection with PZP could cause them to suffer diseased ovaries and depressed estrogen-levels — in addition to infertility and, potentially, sterility. Consider the magnitude of the risk — the PZP-in-question is a horse-size dose.

~ Marybeth Devlin, Wild Horse Advocate

Protect Mustangs is an organization who protects and preserves native and wild horses.

Does PZP result in wild herds with lower immune systems and potential for die-offs?

PM Tule Elk Males FIghting by austlee

PZP is an immunocontraceptive and pesticide which causes an immune reaction to reject fertilization, while the females still come into estrus. Besides wrecking havoc on the immune system, injecting herds with PZP results in more fighting between males and many other behavior abnormalities.

Tule elk in Pt. Ryes National Seashore (Marin County, California) were part of a PZP (Porcine Zona Pellucida) experiment. Several years later there was a strange die-off.

Wildlife groups blamed park service management for leaving the elk fenced in during a drought–claiming that was the reason for the die-off.

Park service officials said the tule elk had water during the die-off.

“Some wildlife advocates have termed the situation a “die-off” and accuse the park service of allowing the elk to perish behind the fence that prevents them from finding enough food and water. Park service officials have a different view of what caused the population drop, and are hoping that new data will help address these concerns, especially as visitor interest peaks during the fall rutting season.” from:

Listen to Wildlife Ecologist Dave Press Discusses Tomales Point Elk and mention “there was water in the pond up there . . .” at 2:18.


It’s time to connect the dots and ask the obvious question: Did PZP lower the herds’ immune system and genetic diversity to the point of making them vulnerable to a die-off?

With suspect data regarding the long-term use of PZP on wild herds, more questions and answers are needed to prevent a similar die-off in America’s wild horses & burros.

With regards to wild horses, keep in mind what Marybeth Devlin wrote about PZP:

“PZP is a registered pesticide whose mechanism-of-action is to cause auto-immune disease. PZP tricks the immune system into producing antibodies that target and attack the ovaries. PZP’s antibodies cause the mare to suffer ovarian dystrophy, oophoritis (inflammation of the ovaries), ovarian cysts, destruction of oocytes in growing follicles, and depletion of resting follicles. Not surprisingly, estrogen levels drop markedly as the ovaries are slowly destroyed. But PZP’s adverse effects are not limited to the individual animal. As a recent study — which included the Little Book Cliffs, Colorado herd and the McCullough Peaks, Wyoming herd — found, PZP extends the birthing season to nearly year-round. Out-of-season births put the life of the foals and the mares at risk. Further, the same study disclosed that the pesticide causes a delay lasting 411.3 days (1.13 years) per each year-of-treatment before mares recover their fertility after suspension of PZP. However, some mares never recover — they are left permanently sterile, and quickly too. Indeed, yet another study found that sterility could occur in some mares from just three years of PZP injections or from just one treatment if the pesticide were given to a filly before she reached puberty. Because PZP messes with the immune system, it ironically works “best” — sterilizes faster — if the mare has a strong immune system. But, conversely, PZP may not work at all in mares whose immune function is weak or depressed. So, the pesticide discriminates against the very horses that Nature has best equipped for survival against disease while favoring and selecting for the immuno-compromised. Worse yet, tests performed via radioimmunoassay indicated that PZP antibodies are transferred from mother to young via the placenta and milk. The transferred antibodies cross-react with and bind to the zonae pellucidae of female offspring, as demonstrated by immunofluorescent techniques.”  [From:]


Pm PZP Darts

Links of interest™:

Immunocontraception (Wikipedia):

“Whenever an immune response is provoked, there is some risk of autoimmunity. Therefore immunocontraception trials typically check for signs of autoimmune disease.[17] One concern with zona pellucida vaccination, in particular, is that in certain cases it appears to be correlated with ovarian pathogenesis.[2] However, ovarian disease has not been observed in every trial of zona pellucida vaccination, and when observed, has not always been irreversible.[18]”


Autoimmune disease (Wikipedia): 

“Autoimmune diseases arise from an abnormal immune response of the body against substances and tissues normally present in the body (autoimmunity). . .”


ZonaStat-H is the EPA restricted-use pesticide–PZP–for wild horses and burros the registrant calls “pests”:


Tule elk:


Tule elks at Pt. Reyes National Seashore (National Park Service):


Challenges face tule elk management in Point Reyes National Seashore

“Earlier this year park service officials revealed that more than 250 tule elk died inside the fenced area over a two-year period, in part because pools that the herds rely on for water had gone dry. Meanwhile, ranchers are complaining about the free-range elk getting on their land and eating grass and drinking water intended for their dairy cattle and other agricultural operations.”


Paratuberculosis or Johne’s disease (Wikipedia):


Testing for Mycobacterium avium subsp. paratuberculosis infection in asymptomatic free-ranging tule elk from an infected herd.

“Forty-five adult tule elk (Cervus elaphus nannodes) in good physical condition were translocated from a population located at Point Reyes National Seashore, Marin County (California, USA), to a holding pen 6 mo prior to release in an unfenced region of the park. Because infection with Mycobacterium avium subsp. paratuberculosis (Mptb) had been reported in the source population, the translocated elk underwent extensive ante-mortem testing using three Johne’s disease assays: enzyme linked immunosorbent assay (ELISA); agar gel immunodiffusion assay (AGID), and fecal culture. Isolation of Mptb was made from fecal samples in six of 45 elk (13%). All AGID results were negative while ELISA results for 18 elk (40%) were considered elevated. Elevated ELISA results or Mptb isolation from fecal samples were obtained for 22 of 45 elk (49%); these elk were euthanized and necropsied. Mycobacterium avium subsp. paratuberculosis was isolated from tissue in 10 of 22 euthanized elk (45%); of these 10 cases of confirmed infection, eight had elevated ELISA results (80%) and four were fecal culture positive (40%). One of 10 cases had histopathologic lesions consistent with Mptb infection. Mycobacterium avium subsp. paratuberculosis was also isolated from tissue from one of eight fetuses sampled. The number of tule elk found to be infected was unexpected, both because of the continued overall health of the source herd and the normal clinical status of all study animals.”


Mycobacterium avium subspecies paratuberculosis and Mycobacterium avium subsp. avium infections in a tule elk (Cervus elaphus nannodes) herd. 2006. 

“Between 2 August and 22 September 2000, 37 hunter-killed tule elk (Cervus elaphus nannodes) were evaluated at the Grizzly Island Wildlife Area, California, USA, for evidence of paratuberculosis. Elk were examined post-mortem, and tissue and fecal samples were submitted for radiometric mycobacterial culture. Acid-fast isolates were identified by a multiplex polymerase chain reaction (PCR) that discriminates among members of the Mycobacterium avium complex (MAC). Histopathologic evaluations were completed, and animals were tested for antibodies using a Johne’s enzyme-linked immunosorbent assay (ELISA) and agar gel immunodiffusion. In addition, 104 fecal samples from tule elk remaining in the herd were collected from the ground and submitted for radiometric mycobacterial culture. No gross lesions were detected in any of the hunter-killed animals. Mycobacterium avium subsp. paratuberculosis (MAP) was cultured once from ileocecal tissue of one adult elk and was determined to be a strain (A18) found commonly in infected cattle. One or more isolates of Mycobacterium avium subsp. avium (MAA) were isolated from tissues of five additional adult elk. Gastrointestinal tract and lymph node tissues from 17 of the 37 elk (46%) examined had histopathologic lesions commonly seen with mycobacterial infection; however, acid-fast bacteria were not observed. All MAC infections were detected from adult elk (P = 0.023). In adult elk, a statistically significant association was found between MAA infection and ELISA sample-to-positive ratio (S/P) > or = 0.25 (P=0.021); four of five MAA culture-positive elk tested positive by ELISA. Sensitivity and specificity of ELISA S/P > or = 0.25 for detection of MAA in adult elk were 50% and 93%, respectively. No significant associations were found between MAC infection and sex or histopathologic lesions. Bacteriologic culture confirmed infection with MAP and MAA in this asymptomatic tule elk herd. The Johne’s ELISA was useful in signaling mycobacterial infection on a population basis but could not discriminate between MAA and MAP antibodies. The multiplex PCR was useful in discriminating among the closely related species belonging to MAC.
Between 2 August and 22 September 2000, 37 hunter-killed tule elk (Cervus elaphus nannodes) were evaluated at the Grizzly Island Wildlife Area, California, USA, for evidence of paratuberculosis. Elk were examined post-mortem, and tissue and fecal samples were submitted for radiometric mycobacterial culture. Acid-fast isolates were identified by a multiplex polymerase chain reaction (PCR) that discriminates among members of the Mycobacterium avium complex (MAC). Histopathologic evaluations were completed, and animals were tested for antibodies using a Johne’s enzyme-linked immunosorbent assay (ELISA) and agar gel immunodiffusion. In addition, 104 fecal samples from tule elk remaining in the herd were collected from the ground and submitted for radiometric mycobacterial culture. No gross lesions were detected in any of the hunter-killed animals. Mycobacterium avium subsp. paratuberculosis (MAP) was cultured once from ileocecal tissue of one adult elk and was determined to be a strain (A18) found commonly in infected cattle. One or more isolates of Mycobacterium avium subsp. avium (MAA) were isolated from tissues of five additional adult elk. Gastrointestinal tract and lymph node tissues from 17 of the 37 elk (46%) examined had histopathologic lesions commonly seen with mycobacterial infection; however, acid-fast bacteria were not observed. All MAC infections were detected from adult elk (P = 0.023). In adult elk, a statistically significant association was found between MAA infection and ELISA sample-to-positive ratio (S/P) > or = 0.25 (P=0.021); four of five MAA culture-positive elk tested positive by ELISA. Sensitivity and specificity of ELISA S/P > or = 0.25 for detection of MAA in adult elk were 50% and 93%, respectively. No significant associations were found between MAC infection and sex or histopathologic lesions. Bacteriologic culture confirmed infection with MAP and MAA in this asymptomatic tule elk herd. The Johne’s ELISA was useful in signaling mycobacterial infection on a population basis but could not discriminate between MAA and MAP antibodies. The multiplex PCR was useful in discriminating among the closely related species belonging to MAC.”


Epizootic of paratuberculosis in farmed elk




Immuno-Contraception Research for Managing Tule Elk Population – Phase I Scheduled to Begin on August 6, 1997

“. . . Funding for tule elk projects has come from a variety of sources. To date, monetary support and in-kind services for the tule elk project has been received from the Rocky Mountain Elk Foundation, Point Reyes National Seashore Association, Committee for the Preservation of Tule Elk, California Department of Fish and Game, The Humane Society of the United States (HSUS), University of California at Davis, the National Park Service Natural Resource Preservation Program and In Defense of Animals.” [Evidently Suzanne Roy, currently the Director of the American Wild Horse Preservation Campaign–who pushes PZP based management–was working for IDA at the time.]


Immuno-Contraception Research for Managing Tule Elk Population – Phase II Scheduled to Begin on June 15, 1998

“. . . During the second phase of the contraceptive research project, the first vaccine will be administered by direct syringe injection. To administer the injection, 30 elk will be captured from a helicopter and hobbled by ground crews. Scientists will gather data on the individual elk and place a radio collar on each of the elk. The collar will allow scientists to follow the individual elk to determine the effectiveness of the contraceptive. After several weeks, a booster shot will be remotely administered, from ranges of 30 to 150 feet, by means of self-injecting darts. The darts are brightly colored and easily retrieved. A single annual booster inoculation will be administered to continue contraceptive effects for successive breeding seasons.”


Use of porcine zona pellucida (PZP) vaccine as a contraceptive agent in free-ranging tule elk (Cervus elaphus nannodes). published 2002: 

Abstract (note only a 5 year study. Why aren’t they studying the truly long-term effects?)
The potential for the application of porcine zona pellucida (PZP) immunocontraception in wildlife population management has been tested over a 15 year period and promises to provide a useful wildlife management tool. These studies have provided evidence indicating that the use of PZP immunocontraception in wildlife: (i) is effective at both the physiological and population level (Liu et al., 1989; Kirkpatrick et al., 1996; Turner et al., this supplement); (ii) is deliverable by remote means (Kirkpatrick et al., 1990; Shideler, 2000); (iii) is safe in pregnant animals (Kirkpatrick and Turner, this supplement); (iv) is reversible (Kirkpatrick et al., 1991; Kirkpatrick and Turner, this supplement); (v) results in no long-term debilitating health problems (Kirkpatrick et al., 1995; Turner and Kirkpatrick, this supplement); (vi) has no implications for passage through the food chain (Harlow and Lane, 1988); and (vii) is reasonably inexpensive (J. F. Kirkpatrick, personal communication). This report presents the results of a 5 year study in tule elk (Cervus elaphus nannodes), 3 years of which were on the application of PZP immunocontraception to an expanding elk population living in a wilderness area of Point Reyes National Seashore in Marin County, CA…”


Copyright Protect 2016

Lies, subterfuge and PZP

PM PZP Dr liu

Forcibly drugging wild mares with PZP at the Carson Prison


Carl Mrozek

Unfortunately, the secret mandate to turn our public lands into vast oil, gas and coal fields–interspersed with millions of cattle under Bush–Cheney has continued unabated under Obama with geothermal fields, plus solar and wind farms being added to the mix of revenue generating initiatives, many on lands reserved by law for primary use by wild horses and burros.

Even as their herds diminish under constant assault by all of these special interests on public lands, wild horses continue to be scapegoats for degradation of public lands due to overpopulation, by the BLM which over-counts then by at least 200% while greatly exaggerating their rate of population  increase–based on optimal conditions and zero mortality.

BLM’s solution to this fabricated overpopulation explosion of wild horses and burros has been massive roundups which are now being replaced by large-scale birth control with PZP (porcine zone pellucida) which results in sterilization after multiple applications. While their tactics have grown more sophisticated, BLM’s overall management program is much the same: Management for Extinction–only slower and less visible than before. Many herds have achieved balanced population levels with little or no management but today all the $$ is on fertility control, short-term and sterilization, long-term–not on natural population control, because this won’t eradicate the herds as ordained by the power brokers in DV. Alas if we don’t wake up, expose and oppose the lies and subterfuge re: the widespread use of PZP soon, our iconic native wild horses may join blue and bowhead whales in the waiting line for extinction–sooner than later.


PM Burros Wild © Carl Mrozek

Carl Mrozek

Carl Mrozek’s nature clips are seen often on CBS Sunday Morning News. He is currently making a documentary on Wild Burros.

Palomino Mustangs on CBS News:

Pine Nut Wild Horses on CBS News: (BLM tried to roundup and decimate this herd but Protect Mustangs stopped the roundup in court)

Red Rock Wild Horses on CBS News: (BLM removed them)

Cold Creek Wild Horses on CBS News: (BLM rounded them up and took them away)


WARNING: Slaughter Fear-mongering pushes forced drugging with PZP on wild horses!

PM HSUS Roundup

Helicopter roundups will increase to administer PZP

95% of the herds can’t be shot with darts in the field

Does the Humane Society of the United States (HSUS) want to take over the Wild Horse and Burro Program, pushing forced drugging with PZP (pesticide made from slaughterhouse pig ovaries for management on underpopulated herds? PZP is a “tool” to manage wild horses to extinction. Science proves PZP (native, 22, etc.) sterilizes after multiple use.

Isn’t the American Wild Horse Preservation Campaign (AWHPC) the wild horse mouthpiece for HSUS? Doesn’t their pledge to “keep them in the wild” written up in the Huffington Post include forced drugging with PZP as their cornerstone management tool? Does HSUS want to create zoo-like settings to “keep them in the wild”? HSUS endorsed the former Secretary of Interior’s Plan, aka the Salazar Plan, in 2009. Now the plan is entering the final wipe-out phase with the help of PZP pushers.

For decades native wild horses have been used by the pharmaceutical industry as lab rats for birth control “research” at huge taxpayer expense. This involves killing wild horses to research drug damage on ovaries and other organs. PZP = Roundups = Cruel Animal Experiments


Links of interest™:

Salazar presents ambits plan to manage West’s wild horses (Washington Post, October 2009)  “Some animal advocates, including Wayne Pacelle of the Humane Society, praised the plan, but others decried it.”

Experimenting on wild horses creates cheap R & D for drug makers

Facebook Forum on PZP:


Equine reproductive immunology Ph.D speaks out in 2010 against using PZP on wild horses

PM President Obama Listen to the Science

November 27, 2010

Jared Bybee, Wild Horse and Burro Specialist

Department of the Interior

Bureau of Land Management

Billings Field Office

5001 Southgate Drive

Billings, Montana 59101-4669

VIA FAX: 406-896-5281

RE: Pryor Mountain Wild Horse Range Fertility Control Preliminary Environmental
Assessment Tiered to the Pryor Mountain Wild Horse Range Environmental Assessment and Herd Management Area Plan May 2009 EA DOI-BLM-MT-0010-2011-0004-EA

Dear Jared Bybee:


I appreciate the opportunity to submit comments on the Pryor Mountain Wild Horse Range
Fertility Control Preliminary Environmental Assessment Tiered to the Pryor Mountain Wild
Horse Range Environmental Assessment and Herd Management Area Plan May 2009 EA DOI-BLM-MT-0010-2011-0004-EA. My background is in equine reproductive immunology and wildlife conservation. I applaud the Billings Field Office of the Bureau of Land Management (BLM) for a thoughtful approach to this issue. Cover letter 4700 (010.JB) dated November 2010 and signed by James M. Sparks, Field Manager states that the BLM would consider comments and revision to the EA or unsigned FONSI as appropriate. I urge a “no action alternative” as outlined on page 7 and 8 of the EA. This request is based on two pieces of new scientific evidence about effects of current immuno-contraception use.

Porcine Zona Pellucida (PZP) Contraception

The proposed action as stated on page 7 of this EA would exempt “mares ages 5-10 unless they have produced foals, or are part of a large bloodline.” This is reminiscent of the approach taken with the Assateague Island wild horse population. It is a compromise approach to this issue, in comparison to placing all mares on PZP. However a recent study shows that mitochondrial DNA diversity is low in the Assateague Island horse herd (Eggert et al. 2010). Since mitochondrial DNA is inherited from the mother (mare), this is evidence that female inherited genetics on Assateague Island wild horses is under represented. It is imperative that this be assessed before rolling out a similar management plan for the Pryor Mountain wild horses.

There is a recent Princeton University study on PZP effects. Consecutive PZP applications, analogous to the proposed action plan in this EA, showed that mares gave birth later in the season, and were cycling into the fall months (Nunez et al. 2010). In a state like Montana where freezing temperatures are found in the fall, this can have serious and long term effects on foal survivorship.

I must include a statement on long term consecutive use of PZP. Any form of PZP contraception is not completely reversible in mares depending on the length of use of PZP. Contraception can only be reversed when the antibody titer decreases to 50-60% of the positive reference sera (Liu et al. 2005). Mares treated for 7 consecutive years do not return to viable fertility (Kirkpatrick and Turner 2002; Kirkpatrick et al. 2009). The issue of reversible contraception is very important to be able to maintain wild equines in the United States. Long term treatment with PZP has inherent negative potential for this herd.

I am requesting a new look at the proposed fertility control action for the Pryor Mountain wild horses.


Christine DeCarlo, Ph.D.

Lori S. Eggert, David M. Powell, et al. (2010). “Pedigrees and the Study of the Wild Horse
Population of Assateague Island National Seashore.” Journal of Wildlife Management
74(5): 963-973.

J. F. Kirkpatrick, A. Rowan, et al. (2009). “The practical side of immunocontraception: zona
proteins and wildlife.” J Reprod Immunol 83(1-2): 151-7.

J. F. Kirkpatrick and A. Turner (2002). “Reversibility of action and safety during pregnancy of immunization against porcine zona pellucida in wild mares (Equus caballus).” Reprod
Suppl 60: 197-202.

I. K. Liu, J. W. Turner, Jr., et al. (2005). “Persistence of anti-zonae pellucidae antibodies
following a single inoculation of porcine zonae pellucidae in the domestic equine.”
Reproduction 129(2): 181-90.

Cassandra M. V. Nunez, James S. Adelman, et al. (2010). “Immunoctraception in Wild Horses (Equus caballus) Extends Reproductive Cycling Beyond the Normal Breeding Season.” PLos ONE 5(10): 1-10.

(Posted for educational purposes)


PZP advocates put wild horses at risk of sterilization after roundup

Stop the Roundups!

Protect Mustangs calls for a freeze on roundups for scientific reevaluation

Tonopah, NV (October 31, 2014)–The Battle Mountain District, Tonopah Field Office is rounding up about 120 wild horses from within the Reveille Allotment and Herd Management Area (HMA) located approximately 50 miles east of Tonopah, NV to remove alleged excess wild horses on 600,000 acres of public land.

“The BLM is wiping out America’s wild horses and taxpayers are paying for the abuse,” states Anne Novak, executive director of Protect Mustangs. “We need to stop the roundups and protect our native wild horses.”

The roundup will stampede native wild horse families by helicopter over a fragile ecosystem and possible sage grouse habitat in the Great Basin Desert. Often wild horses are injured and die in roundups. The treacherous roundup is paid for with tax dollars, and began October 30, 2014. Most herds need to be rounded up before given PZP.

After the roundup, approximately 70 wild horses will be permanently removed, 60 wild horses will be sent to holding facilities in Ridgecrest, California and about 10 horses will be offered for adoption after the roundup in Tonopah, NV on November 8. The remaining 50 wild horses will be released back into the HMA for a post roundup population of 98 wild horses, putting the survivors at risk. The minimum number for genetic variability is 150 wild horses.

Often the BLM returns wild horses with conformation defects to the range, instead of placing them in adoptive homes or long-term holding where they will not breed. Apparently the agency doesn’t realize that by returning wild horses with defects they will ruin the breeding pool. The BLM claims mares selected to maintain herd characteristics will be released back to the HMA. The public must watchdog the agency to ensure wild horses with defects are pulled from the breeding pool and rehomed. Euthanizing them is not an option supported by the American public.

The informed public is outraged over an EPA approved restricted use pesticide called PZP, made from pigs ovaries, to be used on native wild horses. PZP advocates campaign rigorously to treat mares with the Porcine Zona Pellucidae (PZP-22) in order to temporarily sterilize mares. PZP advocates hail the use of PZP in spite of the fact that wild horses are underpopulated on millions of acres of public land.

Experimental research on ovary damage in mares given the immunocontraceptive PZP is used to hone the drug for eventual human use. This could be where the “follow the money” piece fits in. Wild horse advocates are furious America’s herds are being used as lab rats. Science has proven the drug sterilizes wild horses after multiple use. PZP advocates are pushing for BLM to manage wild horses “in the wild” using these risky drugs.

The devastation of wild horses in the Reveille Allotment appears to be subject to a 1987 District Court Order and two orders issued by the Interior Board of Land Appeals (IBLA) in 2001 and 2002, requiring BLM conduct an annual inventory of wild horses in the Reveille Allotment and initiate a roundup to remove alleged excess native horses from the Allotment when the inventory shows that population numbers exceed the out of date Appropriate Management Level (AML) of 138 horses.

Current AML does not represent healthy herd populations and lacks scientific merit. AML must be updated to ensure healthy herds remain on public land. The herd census must never fall below 150 wild horses to maintain genetic variability.

The current estimated population, based on previous inventory flights is 168 wild horses, according to BLM. This is the low end of the genetic viability scale. The orders need to be challenged based on scientific reevaluation of wild horses benefiting the ecosystem as a native species, livestock causing range damage and the minimum number of wild horses needed for genetic variability.

“We must ensure native wild horses can survive upcoming environmental changes,” states Anne Novak, executive director of Protect Mustangs. “The minimum population for a genetically variable herd is 150. Why are PZP advocates and the BLM allowing wild horse herds to fall below safe numbers?”

According to a press release from National Academy of Sciences (NAS) released June 5, 2013, “The U.S. Bureau of Land Management’s (BLM) current practice of removing free-ranging horses from public lands promotes a high population growth rate, and maintaining them in long-term holding facilities is both economically unsustainable and incongruent with public expectations,” says a new report by the National Research Council.

The NAS report states there is “no evidence” of overpopulation. Only tobacco science and spin backs up BLM’s population claim to justify roundups and fertility control/sterilizations. PZP advocates lobbied NAS to have fertility control recommended even though the herds are underpopulated.

Roundup activities within the Reveille HMA were analyzed in the 2010 Reveille HMA Wild Horse Gather Plan and Environmental Assessment (EA) and the 2014 Reveille Wild Horse Gather Determination of NEPA Adequacy (DNA). The EA, DNA, and Decision Record can be accessed on the Reveille Wild Horse Gather website:

Members of the public are encouraged to witness the helicopter stampede and document America’s icons losing their freedom to spread awareness that cruel roundups must stop. Observation protocols and visitor information are available at The BLM will post updates, photos and other information about the roundup on the Reveille website and on the hotline at 775-861-6700 throughout the course of the roundup.

The BLM is wiping out wild horses for the extractive industry and New Energy Frontier in the West. The agency manages more than 245 million acres of public land, the most of any Federal agency. This land, known as the National System of Public Lands, is primarily located in 12 Western states, including Alaska. The BLM also administers 700 million acres of sub-surface mineral estate throughout the nation. The BLM focuses on their mandate of multiple-use and sustained yield. In Fiscal Year 2013, the BLM generated $4.7 billion in receipts from public lands.

BLM’s roundups disturb the thriving natural ecological balance by disturbing habitat dynamics. This crime against nature causes abnormally high birthrate and puts native wild horses at risk of inbreeding.

“We are calling for an immediate freeze on roundups and removals for scientific reevaluation,” states Novak. “Right now native wild horses are at risk of being ruined by bad policy.”

Protect Mustangs is a nonprofit organization dedicated to the conservation of native and wild horses. The group is against using PZP in the wild. Today most wild herds are threatened with low numbers and a lack of genetic variability. Using PZP in a sanctuary setting where acreage is limited is a different situation. Wild horses must not be managed in the wild as if they were a zoo exhibit.

# # #

Links of interest™:

Info on PZP sterilizing mares: The Effects of Porcine Zona Pellucida Immunocontraception on Health and Behavior of Feral Horses (Equus caballus), Princeton

Princeton study on the pros and cons of adoption and immunocontraception: Not sure about EWA’s position on PZP now they might have embraced it like some others have.

Jamie Jackson’s piece on PZP:

Management of Wild Horses with Porcinezona Pellucida Pellucide: History, Consequences and Future Strategies, Cassandra M.V. Nuñez, Princeton:

Restricted use pesticide info: info: Jan-12.pdf

Injection-Site Reactions in Wild Horses (Equus caballus) Receiving an Immunocontraceptive Vaccine, By James E. Roelle and Jason I. Ransom,

Pilot project to treat wild horses in Fish Springs community


BLM Nevada Advisory Council Endorses Fertility Control Plan (Oct. 20, 2014)

BLM partners with The Cloud Foundation in the Pryors

Why end natural selection in the Pryors?

Are wild horses at risk of being sterilized due to an advocacy campaign?

Ecologist Craig Downer speaks out against using PZP in the Pryors

Horse contraceptive study raises concerns  Horsetalk, NZ:

Appeal to stop the wild horse wipe out

The Horse and Burro as Positively Contributing Returned Natives in North America by Craig Downer PhD candidate:

Wild Horse Conspiracy by Craig Downer:

Conformation defects

Genetic viability

Genetic variability

J. Kirkpatrick team get $100K for wild horse fertility control drug PZP

Making PZP at The Science and Conservation Center

Native wild horses

Petition for shelter and shade for captive wild horses and burros

Petition for 10 year moratorium on wild horse roundups for recovery and studies

Petition to defund and stop the wild horse roundups

Join the Walking Billboard Campaign to STOP THE ROUNDUPS in Nevada

Sample of viral news clippings:

Anne Novak on Twitter:

Protect Mustangs on Twitter:


PZP-22… Do Unintended Side-Effects Outweigh Benefits?

Note: This paper is from 2010. In 2011 Ginger Kathrens decided to support PZP and  fertility control as a member of The American Wild Horse Preservation Campaign. We bring you Kathrens 2010 paper for education purposes only. Her points against PZP were very good.

Position paper
Ginger Kathrens
Volunteer Executive Director
The Cloud Foundation, Inc.
Natural History Filmmaker
August 10, 2010

The BLM is instigating an aggressive immunocontraceptive campaign designed to suppress the growth rate of wild horse herds in the American West. This initiative is supported by Secretary of the Interior Salazar and has been spear-headed by the Humane Society of the United States (HSUS) who must first give their approval before BLM can administer these experimental drugs to wild horse mares.

Because it renders wild horse mares infertile for roughly 22 months, the drug is called PZP-22. It must be administered, for now, by a hand injection rather than a remotely delivered field dart. The mustang mares must be rounded up to receive the drug. If PZP-22 performs as intended the mare will not conceive, in most cases for 22 months beginning the year after she is given the shot. However, during that roughly two-year period, she will cycle monthly, be bred by her band stallion, or a stallion strong enough to capture and breed her. But, she will not settle, and in another month, she will again come back into estrous.

Then, the cycle of breeding the mare and defending her from other stallions is repeated. This continues month after month through the spring, summer and fall seasons until the days shorten and the estrous cycle stops. In the lengthening days of late winter or early spring, the pattern begins again.

HSUS has stated that the drug will “stabilize” wild horse herd populations and has given the approval for the drug to be used 100% of the time as far as we know. This approval has been given despite the fact that over 75% of wild horse herds are not even large enough to meet the minimum requirements for genetic viability. The minimum population size is generally accepted as 150 to 200 adult animals.

The use of an infertility drug in non-viable herds is cause for alarm, but add in the manipulation of the sex ratios by BLM and the situation is even more troubling. BLM is removing more females than males from nearly every wild herd in the west. The natural 50-50 or so percentage of males to females is being artificially manipulated to 60% males and 40% females. There is one herd in Utah that will be skewed to 70% males versus 30% females. Consider how potentially “destabilizing” this will be. Most wild horses live in family bands where one stallion has one or more mares that he defends and breeds. Mares that are PZPed will be bred, will not settle and will come into heat again in a month. The competition for each and every mare will be more intense because there are far more males than females. If there are small foals they could suffer the consequences of the social disruption due to this intentional meddling with the rules of nature.

Let me give you a case in point. In May, while Makendra Silverman and I were visiting Cloud’s herd in the Pryor Mountains of Montana, a foal was born to the mare, Demure, and her band stallion, Sante Fe (whom you may remember from the most recent Cloud film, Cloud: Challenge of the Stallions). The foal was probably less than an hour old when we spotted her standing with her mother, her father, and her grandmother. The four-some were nestled into a forested ridge about 200 yards away.

As we hiked closer, we noticed that the foal was having trouble walking. One front leg would cross over the other front leg and she would trip herself and crumple to the ground. This happened time after time and she would fall in a heap. Then Sante Fe jerked his head to attention and walked by the brown lump that was his newborn daughter. He had reacted to the sound of another band coming. We lost sight of him through the trees, but could hear the characteristic screams of the stallions and knew there was a ritual greeting taking place. Sante Fe was warning another stallion to stay away. In a little while he returned to stand near his family protectively. We waited, but the filly lay very still and I couldn’t stand to watch any longer. I got up and walked away, convinced she would not live, and too heartsick to watch her die. Incidentally, when we left, we walked in the direction Sante Fe came from and found his old friend Cloud with his family. It was Cloud that Sante Fe had warned to stay away.

By the end of the day, I knew I had to go look for Sante Fe’s band, expecting to find the lifeless body of the little filly. Instead we found her quite alive—crippled to be sure, but alive. Her close-knit family surrounded her. I wished her good luck, realizing that if she could not walk, she might be left behind.

Two weeks later when we returned. The filly was still alive, very near the place where she was born. There had been a lot of rain and the giant puddle in the road was still full of water within 100 feet of where she stood. Luckily, there was no critical reason for the band to move too far as they had adequate water and ample forage. The foal’s legs still hadn’t straightened out, but they were much better. A friend aptly named her Kandu.

By mid-July we were shocked to see her racing past her mother who trotted just to keep up her once crippled daughter. One knee was still bigger than the other, but the tight tendons of her right leg were stretching out and Kandu was finally experiencing the thrill of running. She dashed in circles on the wide, flower-strewn meadows below the scenic Dry Head Overlook in the Custer National Forest. The little filly with the big heart had survived because of her own iron will and the care of a nurturing mother who lived in a stable family band.

Kandu also had another advantage. She was born at the right time of the year when the temperatures were warming, the snow was melting and the long growing season was just beginning. Most hooved wild babies are born in the spring in North America when their environments can provide their mothers with the necessary nutrients to survive and produce enough milk for their newborns. That brings me to another point. It is believed that the one year drug is most likely to produce the best results when given in late winter and early spring, yet the majority of the wild mares receiving the drug are rounded up in the summer and fall. It is likely that the spike in out-of-season births (fall and even winter) we saw in the Pryors to PZPed mares was due to the drug being given at the wrong time of the year. Remember that a round up is necessary to administer the new drug which is PZP-22. This presents a conundrum. If  mares must be rounded up in order to administer the drug by a hand injection, how do you do this safely in late winter or early spring? The answer is, you cannot if the capture method is by helicopter. Mares due to foal or those with tiny foals cannot be stressed with the long runs inherent in helicopter roundups. We saw what happened just recently in Calico and Tuscarora.

Now place Kandu in the environment in which the BLM is creating in other herds. Just consider what her chances might have been in a herd where there was an overabundance of sexually mature males with a small number of mares who were cycling every month. Perhaps she would have been born going into winter. What chance would a crippled foal have in a situation like this? Sante Fe would have been swamped with stallions trying to steal his mares. Anyone who has seenCloud: Challenge of the Stallions knows what it is like when a group of males attacks one band stallion. Kandu would not have been able to run. She could not even walk. She would have had no chance. She might have been trampled or just left to die. Even her parent’s survival chances would have been compromised due to the expenditure of body reserves used up in the competition between stallions for the few mares.

So, when is PZP-22 an acceptable population control device for wild horse herds? Well, first of all you would need to have an over population of wild horses. That rules out at least 75% of the under populated and genetically non-viable herds. That leaves us with the big herds like Twin Peaks in California. The appropriate management level (AML) for the herd is 450 wild horses and a non-viable AML of 74 for burros in an area larger than the state of Rhode Island—1,250 square miles. On this same land, which is a designated wild horse herd area, BLM allows for over 10,000 head of cattle or over 20,000 head of sheep. Now, how’s that for an equitable distribution of the forage on the range? Unfortunately this is the typical split. Welfare livestock get the lion’s share.

Welfare livestock, which outnumber wild horses, in most cases by 10 to 1 and in some cases by as much as 100 to 1, cost American taxpayers hundreds of millions a year, some estimate the total costs at close to a billion dollars a year.

And they cost thousands of predators their lives. These predators, like mountain lions are killed because they might kill a domestic calf or lamb. It is a scientific fact that the big cats have kept the Montgomery Pass Wild Horse Herd in check for nearly 30 years—no roundups, no drugs, no management. In the Pryor Mountains where Cloud lives, the cats kept the herd at zero population growth for four years until the BLM stepped in to encourage the increased killing of the lions. Bottom line, if the goal is the nearly cost-free natural management of wild horse herd areas, mountain lions must be protected so that a nature crafted predator-prey relationship calls the shots—not us humans.

Having said all this, I believe there is a time and a place when PZP could be used if the parameters below were adhered to:

1. The drug can only be remotely delivered at the right time of the year.

2. The herd does not have a skewed sex ratio favoring males.

3. The herd is genetically viable (i.e. at least 200 adult breeding animals).

Meanwhile, here is what I would work on if I were a BLM wild horse manager:

  • Work with the Fish and Game folks to protect the mountain lions
  • Reduce the forage allocated to welfare livestock
  • Open up the fenced off water sources to all wildlife, including wild horses and burros
  • Remove the thousands of miles of fencing that limits the free-roaming behavior of wild horses  and burros
  • Release the healthy wild horses in holding to the millions of acres taken away from them since Congress unanimously passed the Wild Horse and Burro Act.

So often, well intentioned humans can make unwise choices when it comes to the natural world, and this is what I fear is happening with the use of infertility drugs. I hope wild horse advocates, wildlife enthusiasts, humane organizations, public lands extractive users, and the BLM can have substantive, civil discussions on this issue. I look forward to the day when we all might work together to make a better home on the range for our beloved wild horses and burros.

Happy Trails!

Ginger Kathrens

Immunocontraceptives: Tomorrow’s birth control?

Protect Mustangs is against using PZP and other immunocontraceptives on wild horses and burros at this time because it has not been proven that the herds are overpopulating nor damaging the thriving natural ecological balance and it appears to be risky.

The Bureau of Land Management’s (BLM) Appropriate Management Level (AML) is skewed ridiculously low to appease the public land mining, ranching and energy interests. Livestock is permitted on wild horse rangelands with livestock outnumbering wild horses and burros at more than 50 to 1.

We are very concerned about the low wild horse and burro population levels–estimated at less than 18,000 for the entire West–due to 3 years of roundup rampage.

Roundups will continue in order to administer fertility control unless they are permanently sterilizing the wild horses during roundups now.

Darting is not only a biohazard but is also impractical on rough terrain unless the BLM or their agents are chasing wild horses in helicopters to shoot them with the drug. Chasing herds is cruel.

The 1971 Act made it illegal to chase wild horses and burros with aircraft. Sadly The Act has been whittled away by enemies of the American wild horse and burro. Protect Mustangs is against helicopter roundups and terrorizing wild herds by chasing them over rough terrain where foals have their feet run off and die.

Predators, such as mountain lions, are reducing the population the way nature intended. We support allowing predators on the range.

Immunocontraceptives appear to have many drawbacks that you will read about in the article below. Most studies are paid to prove the drugs are OK so it’s important to notice the negative aspects for a more accurate perspective.

Fertility control is a billion dollar business for the human market. One must question the ethics of using America’s icons as lab rats.

Cross-posted  from Pennmidwifery

By Bonnie Urquhart, R.N.

Native Wild Horses in Utah (Photo © Cynthia Smalley, all rights reserved)

Feral mares grazing on Assateague, a barrier island off the Maryland coast, benefit from a contraceptive strategy that would leave many women envious. Their fertility is curbed by a method that employs neither hormones nor devices, but instead convinces the immune system to target reproductive components and render them inactive. Derived from the ova of pigs, the porcine zona pellucida (PZP) vaccine has been administered annually via dart gun to regulate the fertility of these fast-breeding animals since 1988.

An immunized mare comes into come into heat and mates as usual, but as soon as she ovulates, her immune system considers her endogenous zona pellucida foreign and spackles it with antibodies, blocking fertilization with an effectiveness rate of 90-100 percent (Kirkpatrick, Turner, Liu, Fayrer-Hosken, & Rutberg, 1997). Immunocontraception does not alter the normal reproductive behavior of these horses, is usually reversible if used for less than seven years, and does not appear to harm unborn foals if the mother is accidentally injected while pregnant. Until this approach was developed, feral horse overpopulation was a chronic headache for wildlife biologists determined to keep the large animals from outstripping their food supply and outcompeting native wildlife.

Vaccination against pregnancy is itself a unique concept. Traditional vaccines are derived from foreign proteins that sensitize the body to fight off microbial invaders. Immunocontraceptives reprogram the body to attack part of itself by attaching it to a foreign, non-tolerated molecule (Sprenger, 1995) (Schrater, 1995). By focusing on different target molecules, researchers can prime the immune system to thwart the production and transport of gametes, disturb the interaction of the gametes that leads to fertilization, or interfere with implantation. Zona pellucida vaccines focus on what may be the ideal target-the translucent glycoprotein extracellular matrix, surrounding all mammalian ova, that sperm must penetrate to achieve fertilization.

Nearly 100 species have been successfully contracepted with PZP vaccines, including rabbits, dogs, deer, elephants, gray seals, and non-human primates, as well as amphibians and fish. “Its application to wildlife…has been spectacular. We are fourteen years down the road with wildlife and it comes close to being the perfect agent,” says Dr. Jay Kirkpatrick, reproductive physiologist and developer of the PZP vaccine used today for wildlife management (personal communication, October 23, 2001).

Zona pellucida vaccines were being for considered for human contraceptive use long before Kirkpatrick’s research group adapted it for wildlife. Around the time it gained favor with wildlife biologists, researchers seeking human application were becoming quite discouraged. Native pig protein was not suitable for human use, and researchers were unable to develop an effective recombinant or synthetic form of human ZP (Kirkpatrick, 2001). Molecular biologists could synthesize the protein backbone of the molecule, but not the carbohydrate components. Without the carbohydrates, the vaccine would trigger immune response, but could not block fertilization.

Another problem is the vaccine’s tendency to become irreversible over time. Immature eggs within the ovaries are also surrounded by zona pellucida. An agent that sensitizes the woman against zona pellucida not only would cause her body to attack its mature ova at ovulation, but could also provoke an immune attack on her immature egg cells and inflammatory destruction of the ovary itself, causing permanent infertility (Feng, Sandlow, Sparks, & Sandra 1999) (Richter, 1996).

Adverse autoimmune reactions resulting in disruption of folliculogenesis and depletion in the primordial follicle pool have been observed in the ovaries of mice (Patterson, Jennings, van Duin, & Aitkin, 2000). Mares, rabbits, and dogs maintained on long-term PZP have sometimes shown abnormal hormonal profiles and altered estrus cycles. A wild mare vaccinated for three years might take between one and six years to regain fertility. After seven years, she may become permanently infertile. Women who desire a reversible method would find this effect unacceptable, but clinicians might someday find zona pellucida vaccines an attractive option for women who have finished childbearing.

Human immunocontraceptive research is not new. At least twelve studies in the 1920s and 1930s evaluated immunocontraception in the human female, but the trials were not successful and “unspecified ethical restrictions” ended the research (Richter, 1996). Better understanding of immune function and molecular biology has revived interest in immunocontraceptive research over the past two decades.

The most suitable candidates for contraceptive vaccine development are molecules on the surface of the gametes or on the fertilized ovum and early embryo and the hormones hCG and GnRH. Anti-gamete vaccines are the most attractive option because they do not disrupt an embryo after fertilization or alter the hormonal balance, but researchers have so far been unable to reliably block fertilization without introducing cross-reactions with other tissues (Schrater, 1995).

Bringing a product from the laboratory to the pharmacy is a long and expensive process, and funding sources are limited (Klitsch, 1995). After selecting a target molecule for study, biologists must isolate, characterize, and synthesize effective molecules from sperm or ova; understand mechanisms by which the immune system blocks fertility; develop an effective, benign adjuvant; create reliable, inexpensive tests to monitor fertility status in immunized individuals; and carefully evaluate the product for immunological and other side-effects (O’Rand & Lea, 1997) To market an effective immunocontraceptive, developers must progress from creating the vaccine in the laboratory to preclinical studies to clinical trials (Feng, Sandlow, Sparks, & Sandra 1999).

Because research and development are costly and regulatory obstacles to new drugs are forbidding, any pharmaceutical company that puts an immunocontraceptive on the market is likely to emphasize its effectiveness, play down adverse findings, and energetically court clinicians with free samples and gadgets. Artfully crafted advertisements will spark public excitement over this innovative contraceptive method, and as a result patients will request the medication without understanding much about its action. The CNM will serve as intermediary between hyperbole and hope, keeping clients grounded in reality as they discuss benefits and possible adverse outcomes.

Vaccines targeting human chorionic gonadotropin (hCG) show a higher likelihood of success than many other immunocontraceptive projects. Produced by the embryo to sustain progesterone production, hCG allows the pregnancy to establish and maintain itself. If antibodies disable the hCG molecule, progesterone drops and uterine endometrium sheds, preventing implantation. Because the result is loss of an early pregnancy, anti-abortionists strongly oppose developing an effective hCG vaccine and block U.S. government grants that would speed research (Klitsch, 1995). By 1995, three prototype hCG vaccines had undergone limited clinical trials in women (Schrater, 1995). The initial three injections lasted about 6 months, and did not affect menstrual cycles.

Unfortunately, the chemical similarity of hCG to luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH) apparently induces cross-reactions elsewhere in the hormonal system. Blocking some hormones and interfering with feedback mechanisms could conceivably wreak endocrine havoc, perhaps irreparably damaging the thyroid and the pituitary glands (Feng, Sandlow, Sparks, & Sandra 1999) (Richter,1996). The vaccinated woman would produce and then attack reproductive hormones, continuously creating immune complexes that could cause tissue damage. Or perhaps this reaction would prove to be benign; in short-term clinical trials of the hCG vaccine, all subjects developed cross-reactive antibodies to LH, and all continued to cycle normally. Female rhesus monkeys immunized repeatedly for seven years with ovine (sheep) LH became infertile but continued to ovulate, had regular menstrual cycles, and maintained normal pituitary function (Schrater, 1995).

Higher on the hypothalamic-pituitary-ovarian axis is gonadotropin- releasing hormone (GnRH), the hormone that spearheads the production of sex steroids in both men and women. The National Institute of Immunology and the Population Control Council have tested a GnRH vaccine on human subjects, including breastfeeding women (Schrater, 1995). The result is effective-but dramatic. The GnRH vaccine essentially effects non-surgical castration, halting testosterone production in men (with accompanying impotence and loss of body hair) and effecting menopause in women (Richter,1996). Hormonal supplements could remedy the deficit, but consumers are unlikely to find this approach acceptable. This technology would be more applicable to veterinary medicine, making possible non-traumatic spaying and castration and in wildlife biology the reduction of, say, deer herds in suburban neighborhoods where hunting is not feasible. Trials of GnRH vaccines on Norway rats resulted in 100 percent sterility in both sexes (Miller, 1997).

Potentially promising are experimental vaccines that target male FSH receptor proteins, inducing men to produce low-quality sperm incapable of fertilization but sparing them the need for exogenous testosterone supplementation. Other biologists have targeted prostaglandinF2, oxytocin, and structural placental antigens (Feng, Sandlow, Sparks, & Sandra 1999). It is the advanced practice nurse who must serve as the intermediary between technology and the client, translating technical information and exploring treatment options while considering the safety of the product.

Vaccines triggering an immune response against sperm could be used by either men or women. Laboratories have experimented with structural and functional antigens on the sperm itself, and with spermatic enzymes. Target specificity is the stumbling block-an immune response that incapacitates sperm also tends to induce the immune system to attack other organs and tissues as well.

With immunocontraceptives, there is often a reciprocal relationship between specificity and effectiveness. If a vaccine is very specific to one small antigen, there is little danger that the immune system will attack similar targets, but contraceptive action is ineffective. An agent that targets several components is much more effective, but the immune response is likely to involve other tissues. The immune system is intimately connected to every part of the body. The potential for an untoward autoimmune response is great, and tissue injury may be difficult to prevent. But perhaps this damage is purely theoretical: anti-sperm antibodies frequently occur in vasectomized men and some women spontaneously become immune to sperm with no identifiable systemic damage (Schrater, 1995) (Diekman & Herr, 1997). Women sometimes develop immune responses against their own zona pellucida as well, and seem to suffer no other ill effects (Schrater, 1995).

Kirkpatrick reports that Assateague mares, freed from the stress of pregnancy and lactation, have enjoyed improved health since the vaccine program started (Barber &Frayer-Hosken, 2000). Studies in horses and dogs show that although ovarian damage occurs, the PZP antibodies in a vaccinated animal do not cross-react with major organ systems such as the brain, heart, and urinary tract (Barber & Frayer-Hosken, 2000). Research with horses and other animals indicates that offspring born to previously contracepted mares, and even mares who were accidentally vaccinated while pregnant, appear normal and go on to produce normal foals themselves. Damage to human fetuses might be more subtle, perhaps manifesting in a chronically overstimulated or sluggish immune system or in hormonal anomalies that might not appear until puberty. We just do not know.

Potential lawsuits make domestic pharmaceutical companies reluctant to engage in immunocontraceptive research, but several companies around the world are optimistic. Canadian biotech firm Immucon has a patent for a male immunocontraceptive vaccine that neutralizes sperm fertilizing capacity by targeting a crucial zona pellucida sperm-binding protein at the level of the epididymus. The company expects to market the vaccine between 2005 and 2007. Immucon believes that reversible male immunocontraceptives will be an $850 million-a-year industry worldwide, and female immunocontraceptives will be worth $990 million a year (Immucon, 2001). Liability reform may encourage the pharmaceutical industry to conduct more contraceptive research (Klitsch, 1995).

Researchers are also exploring injectable agents that could render a man or woman permanently sterile. This could eliminate the pain and expense of tubal ligation or vasectomy while effectively ending childbearing.

Four out of every ten pregnancies in the world are unplanned-80 million a year (AGI,1997). The World Health Organization estimates that between eight million and 30 million unplanned pregnancies are the result of inconsistent or incorrect use of contraceptive methods or from method-related failure, and 120 to 150 million married women want to limit or space their pregnancies but lack the information and services to do so. Worldwide, 55,000 unsafe abortions take place every day, 95 percent of them in developing countries. Every day, more than 200 women die from these procedures ( Optimally spaced and planned pregnancies benefit the health of both mothers and children. World population is expected to reach 10 billion by the year 2050, and overpopulation can lead to poverty, famine, disease, depletion of resources, and environmental degradation (Feng, Sandlow, Sparks, & Sandra 1999).

A safe, reliable immunocontraceptive agent could be the family planning strategy of choice for women in developing countries. Proper implementation, however, could strain resources. Clinicians must perform pregnancy tests before immunization and periodically screen recipients to verify that the vaccine is still effective.

If the perfect immunocontraceptive is developed, there would be tremendous potential for misuse and coercion by population-control programs to reduce the birth rate of the poor, non-whites, and people in Third World countries (Richter,1996). (Schrater, 1995). Judith Richter writes in The Ecologist “within this conceptual framework, birth control is regarded as a weapon of war against the ‘teeming multitudes,’ a war in which people are treated as mere numbers or statistics to be controlled, manipulated reduced and dispensed with” (Richter,1996, page 58). The reproductive rights of individuals could become secondary to the perceived need of the population as a whole.

There have been many documented cases of IUD insertion and sterilization procedures carried out without a woman’s knowledge or consent. Immunocontraception would make it much easier to surreptitiously render a woman infertile. Clinics could administer long-acting contraceptive vaccines to uninformed, unaware patients who think the injection is for protection against disease. Some immunocontraceptive agents, such as anti-sperm vaccines, could sensitize a woman for life, and it is likely she would never know that her inability to conceive was artificially induced. (Richter,1996).

Population-control programs usually focus on women because they are the ones who become pregnant. The subordinate status of women in much of the world makes them less likely to resist coercive fertility regulation policies. Conversely, state-imposed vasectomy programs in China and India led to social unrest and the downfall of a government (Schrater, 1995).

Immunocontraceptive clinical trails show great variability in effectiveness although research subjects are healthy, well-nourished individuals in supervised health-care settings. How effective will these vaccines be when used on anemic, malnourished people with little access to care? Immune response varies greatly between individuals and even within an individual, and the duration of protection from pregnancy may be difficult to predict. Individuals with the tendency towards allergies and autoimmune disease could experience an exaggerated reaction that might render them permanently infertile (Richter,1996). Diseases that suppress immunity might reduce the effectiveness of the vaccine.

Researchers talk of developing a finger-stick kit that could be used in the home so that vaccine recipients could monitor their own fertility status and use additional protection if titers are low. It is unclear how feasible these kits would be in Third World counties with few health care supplies.

The ideal immunocontraceptive would be a highly effective, fully reversible vaccine effective for a predictable period. Today’s immunocontraceptives are prototypes in need of improved formulation that will give longer acting, reliable responses with little chance of cross reaction, and offer a high level of protection against pregnancy. Our knowledge of molecular biology grows daily. New vaccine technology may soon isolate target antigens that are much different from the substances synthesized now, creating a safe, effective product that will change the lives of millions. The leadership of nurse midwives will help clients process information and make informed decisions about contraceptive vaccines when they begin to reach the market.


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2001 Bonnie S. Urquhart