This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Turner, J. W. Articles by Kirkpatrick, J. F. Search for Related Content PubMed PubMed Citation Articles by Turner, J. W., Jr Articles by Kirkpatrick, J. F.

Remotely delivered immunocontraception in free-roaming feral burros (Equus asinus)

Regulation of local overpopulations of free-roaming feral equids is in demand worldwide for ecological balance and habitat preservation. Contraceptive vaccines have proven effective in feral horses, which breed seasonally, but no data are available for equids such as the burro, which is reproductively active all year round. In the present study, 27 individually identified female feral burros (Equus asinus) roaming free in Virgin Islands National Park (St John, US Virgin Islands; Lesser Antilles) were remotely treated with pig zonae pellucidae (PZP) vaccine. Between January and May, 16 burros were darted with a 1 ml emulsion of PZP plus Freund's adjuvant. Ten to twelve months later each treated burro was given a single booster injection of PZP plus adjuvant to maintain contraception through a second year. Eleven adult untreated jennies served as controls. Beginning one year after initial vaccination, these burros were monitored for pregnancy and foal production. Collection of data to determine treatment effect was not begun until 12 months after initial treatment to ensure that pregnancies existing before vaccination were not included. Pregnancy was assessed using previously validated methods for steroid metabolite measurement in fresh faecal samples. None of the PZP-treated burros produced foals between 0 and 12 months after the last inoculation. One PZP-treated burro tested positive for pregnancy at 10 months after the final inoculation. During this same period, six of 11 untreated burros tested pregnancy-positive, and four were observed with foals. There was no difference in pregnancy rates among treated, control and randomly sampled jennies between 12 and 24 months after the last inoculation. The results demonstrate that, in free-roaming feral burros that are reproductively active all year round: (1) burros can be accessed for remotely delivered PZP vaccination; (2) PZP contraception is effective; (3) PZP contraception is reversible; and (4) pregnancy can be reliably detected by faecal steroid analysis.

This article has been cited by other articles:

				J. A Duckworth, K. Wilson, X. Cui, F. C Molinia, and P. E Cowan Immunogenicity and contraceptive potential of three infertility-relevant zona pellucida 2 epitopes in the marsupial brushtail possum (Trichosurus vulpecula) Reproduction, January 1, 2007; 133(1): 177 - 186. [Abstract] [Full Text] [PDF]

				D. W Cooper and E. Larsen Immunocontraception of mammalian wildlife: ecological and immunogenetic issues. Reproduction, December 1, 2006; 132(6): 821 - 828. [Abstract] [Full Text] [PDF]

				D. L. Baker, M. A. Wild, M. D. Hussain, R. L. Dunn, and T. M. Nett EVALUATION OF REMOTELY DELIVERED LEUPROLIDE ACETATE AS A CONTRACEPTIVE AGENT IN FEMALE ELK (CERVUS ELAPHUS NELSONI) J. Wildl. Dis., October 1, 2005; 41(4): 758 - 767. [Abstract] [Full Text] [PDF]