Wild Horse Education

Owyhee Update (& a word about immunocontraception)

Yesterday the BLM captured 84 (37 Stallions, 31 Mares, and 16 Foals) wild horses and 2 more have died. The deaths: 9-year-old Paint mare BLM said had “chronic injury (broken jaw) with no prognosis for recovery” and a yearling Grey foal BLM said had “chronic injury (club foot) with no prognosis for recovery.”

Trap was on private land so our observer watched the horses she saw captured the day before loaded onto the semi-truck and shipped off to the off-limits-to-public facility in Sutherland Utah.

The totals for this operation so far:

Captured: 389 (166 Stallions, 152 Mares, and 71 Foals)

Shipped: 205 (76 Stallions, 79 Mares, and 50 Foals)  to Sutherland in Utah, 2 domestics to the NV Brand Inspector.

Deaths: 7

Released: 55 (32 Stallions, 20 Mares, and 3 Foals), the 20 mares treated with PZP-22.

You can see our ongoing team report since the operation began (including the release) HERE

The use of immunocontraception has become muddled in the minds of Congress, media and the public. (note on the budget request that sets aside $11 million for immunocontraception is at the bottom of yesterdays report)

There are inaccurate reports coming out that BLM is releasing mares without being fully treated with “PZP,” an immunocontraception vaccine.

The following is presented to help the public simply understand the discussion and what is currently occurring at roundups and on federal public lands. 

Video below of application of PZP-22 just prior to release of wild mares. One dose is a fully vaccinated wild horse. PZP-22 is both “prime and boost” and one dose is a full treatment. 

Please remember: a substance is not a method and a method is not a substance. “PZP” does not mean “dart.”

“PZP,” (porcine zona pellucida), is a protein based non-hormonal fertility control vaccine. This substance is used in multiple forms. The “wild horse advocate public” generally is aware of 2 forms; the forms referenced as “Native PZP” and PZP-22.

  • “Native” is usually applied via dart using the original vaccine protocol on horses (where two doses are done in the initial treatment year: one as “prime in fall” and one as a “boost in spring,” and then one annual every spring after that) delivers about 12 months of efficacy.
  • PZP-22, usually delivered by a jab-stick in a chute after a roundup, delivers about 22 months of efficacy (video above).
  • There is a third form called “Spay-Vac” that includes a component that attempts to chemically sterilize (not currently used by BLM).

Note: There are new protocols being used with “native PZP” via darting that can increase the length of time of efficacy and may even cause permanent infertility over time. Those are not currently employed by BLM, but those protocols are used outside federal jurisdictions. 

PZP-22 includes the “primer dose” and time released pellets to act as a boosting agent to the immune system. The addition of the pellets allows a single dose to provide, on average, about 22 months of efficacy.

With each application of PZP the immune system responds stronger. Immunocontraception is based on creating a strong response from the immune system. (If you think of how the immune system responds to an allergy, with each allergic response stronger than the last, you get a good idea of how this type of vaccine functions.)

PZP-22 is the type of immunocontraception most often used by BLM. This form of immunocontraception is employed by the agemcy as part of a capture operation.

BLM also uses another fertility control vaccine/agent called GonaCon. GonaCon is not immunocontraception. GonaCon is a hormonal fertility control substance that requires two applications in a 45-day period to achieve 2-5 years of infertility. GonaCon can be darted or used as part of a roundup. BLM has only used GonaCon as part of a roundup. GonaCon is not being used at Owyhee.

The 20 mares released back into the Snowstorm HMA as part of the ongoing Owyhee Complex roundup were fully vaccinated with one dose of PZP-22. So were the mares at Surprise that just ended. Both Owyhee and Surprise are considered by BLM to be “remove to AML and retreat with fertility control.” These are not considered “emergency roundups because wild horses are in bad shape,” these are considered “AML/fertility control.”

We added this information not only to help you navigate the things you hear online (claiming horses during roundups are not fully vaccinated) but to help you navigate your own advocacy.

Reporting the facts does not imply an opinion on those facts. We are trying to give you information.

When you take action items, or talk to your representatives, are you advocating for what you want or what you are told you want? Always read each action item, not just the lead in, before adding your name.

To clarify the current budget debate we will give you the specific language, again, that the Senate and House committees approved for the 2022 budget:

Wild Horse and Burro Management.—The Committee recommends $162,093,000 which supports implementation of the May 2020 plan and includes $11,000,000 for administration of and research on reversible immunocontraceptive fertility control; 

Owyhee is one example.

Our team is back on-site at the trap as the Owyhee roundup continues.

Our legal team will have news soon on our next action.

Categories: Wild Horse Education