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, we identified 27 individual female feral burros (Equus asinus) roaming free in Virgin IslandsNational Park (St John, US Virgin Islands; Lesser Antilles) and remotely treated them with pig zonae pellucidae (PZP) vaccine. Between January and May, we darted 16 burros with a 1 ml emulsion of PZP plus Freund's adjuvant. Ten to twelve months later, we gave each treated burro 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, we monitored these burros for pregnancy and foal production. We did not begin collection of data to determine treatment effect until 12 months after initial treatment to ensure that pregnancies existing before vaccination were not included. We assessed pregnancy using previously validated methods for steroid metabolite measurement in fresh fecal 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 fecal steroid analysis.
BIO:Dr. J. Turner is an endocrinologist (Ph.D., Cornell; Postdoctoral, U.C.L.A., School of Medicine) with expertise focused in reproductive biology and stress physiology. Based at the Medical University of Ohio, he is a Professor of Physiology engaged in teaching and research. He has trained and graduated 18 M.S. and 7 Ph.D. students. His research has addressed 1) since 1975 the development of contraception for free-roaming wildlife (to ameliorate problems of wild animal over populations in fixed-size habitats) and 2) since 1979 the relationship between environmental stress and physiological function (to assess the stress impact of increasingly compromised environments on the homeostasis of their inhabitants). An important component of these endeavors has been the development of humane, non-invasive (remote) methods for physiological monitoring. The research efforts have been fully supported by Federal and/or private funding, yielding 102 peer-reviewed publications, including 6 books. He has served for 19 years on Management Planning Committees of the U.S. Forest Service related to wildlife management, and in 2005 he received the U.S. Forest Service Chief Award for this work. Since 1999 his research studies have focused on a single-injection, multi-year controlled-release contraceptive vaccine and on environmental stress assessment in fishes via fecal cortisol measurement. In 2006 he was awarded the Career Sustained Research Award from the Medical University of Ohio.
John W. Turner, Jr. (Presenter), Ph.D. (Degree)Professor, University of Toledo College of Medical, Department of Physiology and Pharmacology, 3035 Arlington Avenue, Toledo, Ohio 43614-5804, 419 383-4146 (phone); 419 383-6168 (fax); email:
CONTRIBUTING AUTHORS: John W. Turner, Jr., IKM Liu and JF Kirkpatrick
Comparison of Cortisol-Indexed Stress Levels in Parrotfishes Inhabiting Developed vs. Undeveloped Bays on St. John, U.S.Virgin Islands
Coral reefs are in decline worldwide from a combination of natural and human forces. The environmental compromises faced by coral reef habitats and their associated fishes are potentially stressful, with associated impairment of fish reproduction, growth and immunity. In this study we examined stress levels in parrotfishes via measurement of fecal cortisol, a well documented stress indicator. The study site was the Caribbean Island of St. John, USVI, and the target species were adult Sparisoma viride and Scarus vetula. We collected samples via SCUBA and snorkeling from reef 3-8 m depths.Cortisol was extracted from collected feces and measured it in an HPLC-validated enzyme-linked immunosorbent assay (ELISA). Our objectives in this 9-year study were: to establish, for a relatively undeveloped site (Great Lameshur Bay), an extended reference baseline for fecal cortisol as part of assessing its potential as a stress index and, to compare cortisol levels in fishes on a reef associated with extensive coastal development and commercial marine activity (Gallows Point) versus a reef without these activities (Great Lameshur Bay). We collected samples for between site comparisons in February each year exceptwhen we collected samples across several months to assess seasonal cortisol patterns. We also performed fish censuses from 1999-2004 during February at these sites. Despite variation in cortisol levels both within and across years at both sites, across-study cortisol averaged 6.8 fold higher at Gallows Point (47 ±4.15 ng/g dry fecal) than at great LameshurBay (6.89 ±2.63). In all years, Gallows Point cortisol was greater for the years assessed for both cortisol and fish numbers (1999-2004), these parameters were inversely related, i.e., higher cortisol was associated with fewer fishes. Across all months tested in 1999 (Feb, Mar, Apr, and Jun) cortisol levels in Gallows Point exceeded those in GreatLameshurBay. Cortisol in the latter was greater in April and June than in February and March. These data indicate that: 1) a reliable reference baseline for cortisol can be established in a reef area experiencing limited human activity and,2) coastal development and its consequent continuous human presence is chronically stressful to fishes inhabitating proximate coral reefs. These findings encourage use of fish fecal cortisol toward isolating specific anthropomorphic disruptors of the marine environment.
BIO:Dr. J. Turner is an endocrinologist (Ph.D., Cornell; Postdoctoral, U.C.L.A., School of Medicine) with expertise focused in reproductive biology and stress physiology. Based at the Medical University of Ohio, he is a Professor of Physiology engaged in teaching and research. He has trained and graduated 18 M.S. and 7 Ph.D. students. His research since 1979 has included the relationship between environmental stress and physiological function. After 15 years studying the psychophysiology of stress-related disorders in humans he began to assess the stress impact of increasingly compromised environments on the homeostasis of their animal inhabitants. An important component of these endeavors has been the development of humane, non-invasive (remote) methods for physiological monitoring. His career research efforts have been fully supported by Federal and/or private funding, yielding 102 peer-reviewed publications, including 6 books. Since 1997 he has focused on environmental stress assessment in fishes via fecal cortisol measurement. In 2006 he was awarded the Career Sustained Research Award from the Medical University of Ohio.
John W. Turner, Jr., Ph.D., Professor, University of Toledo College of Medical, Department of Physiology and Pharmacology, 3035 Arlington Avenue, Toledo, Ohio 43614-5804, 419 383-4146 (phone); 419 383-6168 (fax); email:
CONTRIBUTING AUTHORS:
John W. Turner, Jr. and Blair DeBuysscher