Op-ed: Wild-horse contraceptives are based on sound science

First Published      Last Updated Jul 07 2015 06:33 pm

In recent months, Friends of Animals and the Project Mustang have put forth a number of claims regarding the use of the fertility control vaccine PZP in wild horses.

These claims aren't based on science or fact. They are so dubious and distorted that it's difficult for those of us in the sciences even to know where to begin in addressing them.

Many of these groups' claims originate in data regarding the small and unusual horse population at Cape Lookout in North Carolina. And even this data has been greatly distorted.

But that's the strategy: stir up controversy, whip up emotions and foster doubt rather than support a science-based and workable strategy for helping horses.

Rather than being "friends" to horses, these groups are helping to perpetuate the current unworkable and inhumane system of wild horse roundups.

Fortunately, many other horse groups, scientists and a growing number of wildlife managers understand that fertility control offers us the best solution for humanely controlling horse populations and, ideally, ending roundups for good.

To get at the truth, reasonable horse advocates, the media and scientists must challenge these groups to back up their claims with facts and science. Here is a list of questions they should be asked, publicly, to answer:

Identify wild horse populations where PZP has disrupted the social structure or social behaviors of the horses. (By definition, this means the disappearance of harem groups, bachelor groups, social hierarchy, or other fundamental social behaviors.) Explain why this hasn't even happened in the population where this theory originated (Cape Lookout).

Identify any wild horse population where PZP has disrupted social organization or social stability to the point of decreasing reproductive success. Explain why this hasn't happened where the theory originated (Cape Lookout).

Identify any wild horse populations where PZP has increased the length of the foaling season and resulted in decreased foal survival. Include Cape Lookout in this answer.

Identify any wild horse population where PZP treatment has resulted in a decrease in body condition scores, or an increase in adult or foal mortality, or a decrease in longevity. Conversely, identify any wild horse populations where PZP treatment has increased body condition scores, decreased mortality and increased longevity

The groups have stated, untruthfully, that the Humane Society of the United States holds a patent on PZP. If this is true, where is the patent number?

The groups state the makers of PZP and the Humane Society profit from the vaccine, but it's actually produced on a non-profit basis. If there were a profit to be made, why aren't for-profit companies making the vaccine (which is not patented)?

Why, after 15 years management with PZP in the highly social species of African Elephants, have there been no changes in social organization or social behavior?

Why, after 25 years of PZP management of 85 different species of animals in more than 200 zoos worldwide, have there been no health or behavioral problems among the treated animals, seen daily by veterinarians and keepers?

PZP has helped end or reduce the need for roundups in all herd management areas where it is routinely used. Roundups and removals continue in areas where it's not used. What do groups expect to change to make these facts untrue?

Provide injury and mortality figures for horse populations treated with PZP and for the same populations during the course of round ups and removal.

Do they believe use of public lands for agriculture, energy development, mining or recreation will be reduced or eliminated to accommodate unmanaged populations of wild horses?

The truth is that, while these groups await an unachievable ideal for wild horses, populations continue to increase, as do roundups and removals. This management scheme costs U.S. taxpayers more than $75 million annually and results in the death and injury of horses. Thousands of horses are removed from their habitats and kept in long-term holding. And the problem only continues.

True friends of these animals support solutions that will help reduce and end the problem, not prolong it.

Jay F. Kirkpatrick, Ph.D., is senior scientist at the Science and Conservation Center, Billings, Mont.