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RESEARCH ARTICLE
Contents Vol 32(8)

Increasing the efficacy of Judas goats by sterilisation and pregnancy termination

Karl J. Campbell A B C H , Greg S. Baxter A , Peter J. Murray D , Bruce E. Coblentz E , C. Josh Donlan F G and Victor Carrion G. C
+ Author Affiliations
- Author Affiliations

A School of Natural and Rural Systems Management, University of Queensland Gatton, Gatton, Qld 4343, Australia.

B Charles Darwin Foundation, Casilla 17-01-3891, Quito, Ecuador.

C Galápagos National Park Service, Puerto Ayora, Isla Santa Cruz, Galápagos, Ecuador.

D School of Animal Studies, University of Queensland Gatton, Gatton, Qld 4343, Australia.

E Department of Fisheries and Wildlife, Nash Hall 104, Oregon State University, Corvallis, OR 97331-3803, USA.

F Department of Ecology and Evolutionary Biology, Corson Hall, Cornell University, Ithaca, NY 14853-2701, USA.

G Island Conservation, Center for Ocean Health, 100 Shaffer Road, Santa Cruz, CA 95060, USA.

H Corresponding author. Email: karl@fcdarwin.org.ec

Wildlife Research 32(8) 737-743 https://doi.org/10.1071/WR05033
Submitted: 22 March 2005  Accepted: 18 October 2005   Published: 20 December 2005

Abstract

The use of Judas goats to locate remnant animals is a potentially powerful tool for enhancing goat-eradication efforts, which are especially important to island conservation. However, current Judas goat methodology falls short of its potential efficacy. Female Judas goats are often pregnant at the time of deployment or become impregnated in the field; pregnant females leave associated goats to give birth, causing downtime of Judas goat operations. Further, male Judas goats may inseminate remnant females. Sterilising Judas goats prior to deployment removes these inefficiencies. Here, we describe two methods (epididymectomy for males and tubal occlusion for females) that sterilise Judas goats while still maintaining sexual motivation and other behaviours associated with intact animals. These surgeries are straightforward, time efficient, and may be conducted in the field by staff with minimal training. Given the widespread and deleterious impacts of non-native herbivores to ecosystems and the importance of Judas operations in detecting animals at low densities, sterilisation and termination of pregnancy should be applied routinely in Judas goat (and possibly other species) programs to increase the efficacy of low-density control operations and eradication campaigns.


Acknowledgments

Felipe Cruz provided encouragement and direction throughout. C. Lavoie managed Santiago JG data, while Project Isabela hunters collected field data. Veterinarians J. Flanagan, D. Forrest, J. Foxworth, D. Kraemer, J. McCosker and J. Romano provided advice on selection of appropriate methods and their application. B. Hampson provided logistical assistance and valuable advice. A. Lisle assisted with experimental design. F. Cruz and J. Flanagan provided comments on a draft manuscript. This project was conducted under the University of Queensland’s Animal Ethics Committee Approval #NRSM/388/00/UQ/CDF/GNPS and NRSM/416/04/CDF/PhD in partial fulfilment of a postgraduate degree (to KJC). Field work was conducted as part of the management activities of the Galápagos National Park Service (GNPS) and the Charles Darwin Foundation for the Galápagos Islands (CDF), to whom we owe thanks. Funding was provided by the CDF, Charles Darwin Foundation Inc., Europe-based Friends of Galápagos Organisations, the GNPS, Lindblad Expeditions, and the University of Queensland. TAME airlines provided reduced fares. Additionally, this work was accomplished with the support of Project ECU/00/G31 ‘Control of Invasive Species in the Galápagos Archipelago’, a donation from the Global Environment Facility (GEF) to the Ecuadorian Government, represented by the Ministry of Environment. Project ECU/00/G31 is implemented by the United Nations Development Program (UNDP) and is executed by the Galápagos National Park Service, Charles Darwin Foundation, National Institute for Galápagos (INGALA) and Ecuadorian Service for Agriculture and Livestock Sanitation – Galápagos (SESA-Galápagos). Additional support was provided by Cornell University (to CJD). Opinions expressed herein belong to the authors and do not necessarily reflect the opinions of GEF/UNDP. This is CDF contribution No. 1017 to conservation of the Galápagos Islands.


References

Althouse, G. C. , and Evans, L. E. (1997). Removal of the caudae epididymides to create infertile boars for use in estrus detection programs. Journal of the American Veterinary Medical Association 210, 678–680.
| PubMed | Asa C. S. (1996). Effects of contraceptives on behavior. In ‘Contraception in Wildlife’. (Eds P. N. Cohn, E. D. Plotka and U. S. Seal.) pp. 157–170. (Edwin Mellen Press: Lewiston, NY.)

Barton K., and Williams P. A. (2001). Passage time for weed seeds in the digestive tract of herbivorous livestock. Landcare Research Contract Report: LC 0001/065.

Beck, C. C. (1973). Vasectomy versus caudal epididymectomy. Veterinary Medicine, Small Animal Clinician 68, 1015–1017.
Braun W. J. (1997). Induced abortion and parturition in the goat. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 556–558. (W.B. Saunders Co.: Philadelphia.)

Bretzlaff K. N., McEntee K., Hixon J., and Ott R. S. (1982). Short estrus cycles after PGF-induced abortions in goats. In ‘Proceedings of the Third International Conference on Goat Production and Disease, University of Arizona Tucson, January 10–15’. p. 498. (Dairy Goat Journal Publishing Co.: Scottsdale, AZ.)

Campbell K. J. (2002). Advances in Judas goat methodology in the Galápagos Islands: manipulating the animals. In ‘Judas Workshop 2002’. (Eds J. Gregory, B. Kyle and M. Simmons.) pp. 70–77. (New Zealand Department of Conservation, Otago Conservancy: Dunedin.)

Campbell, K. J. , and Donlan, C. J. (2005). A review of feral goat eradication on islands. Conservation Biology 19, 1362–1374.
| Crossref | GoogleScholarGoogle Scholar | Estill C. T. (1997). Control of the estrous cycle in swine. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 703–710. (W.B. Saunders: Philadelphia.)

Faugere, O. , Leforban, Y. , Nercy, C. , and Ndiaye, M. (1987). Trial treatment of respiratory diseases of small ruminants in Sine-Saloum (Senegal) using a long-acting oxytetracycline. Revue d’Elevage et de Medecine Veterinaire des Pays Tropicaux (Paris) 40, 31–42.French with English abstract
Gordon I. (1997). ‘Controlled Reproduction in Sheep and Goats.’ (CABI Publishing: Oxon, UK.)

Hart, B. L. , and Jones, T. O. A. C. (1975). Effects of castration on sexual behavior of tropical male goats. Hormones and Behavior 6, 247–258.
| Crossref | GoogleScholarGoogle Scholar | PubMed | King W. B. (1985). Island birds: will the future repeat the past? In ‘Conservation of Island Birds’. (Ed. P. J. Moors.) pp. 3–15. (International Council for Bird Preservation: Cambridge.)

Llewelyn, C. A. , Perrie, J. , Luckins, A. G. , and Munro, C. D. (1993). Oestrus in the British white goat: timing of plasma luteinizing hormone surge and changes in behavioural and vaginal traits in relationships to the onset of oestrus. British Veterinary Journal 149, 171–182.
| PubMed | Memon M. A., and Mickelsen W. D. Goya; H. O. (1997). Examination of the reproductive tract and evaluation of potential breeding soundness in the buck. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 485–488. (W.B. Saunders Co.: Philadelphia.)

Morgan G. (1997). Surgical correction of abnormalities of the reproductive organs of bulls and preparation of teaser animals. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 240–251. (W.B. Saunders Co.: Philadelphia.)

Muller-Schwarze, D. (1991). The chemical ecology of ungulates. Applied Animal Behaviour Science 29, 389–402.
| Crossref | GoogleScholarGoogle Scholar | Neaves W. B. (1975). Biological aspects of vasectomy. In ‘Handbook of Physiology’. (Eds R. O. Greep and E. B. Astwood.). pp. 383–404. (Williams and Wilkins: Baltimore.)

Noordsy J. L. (1994). ‘Food Animal Surgery.’ (VLS Books: Trenton, NJ.)

O’Brien P. H. (1984). Aspects of the behaviour and social organization of the feral goat, Capra hircus L. Ph.D. Thesis, University of Queensland.

Oehme, F. W. (1968). Resection of the bovine epididymis. A procedure for preparing teaser bulls and securing increased weight gain in male feeder cattle. Veterinary Medicine, Small Animal Clinician 63, 603–606.
Ott R. S. (1986). Prostaglandins for induction of estrus, estrus synchronization, abortion and induction of parturition. In ‘Current Therapy in Theriogenology 2’. (Ed. D. A. Morrow.) pp. 583–585. (W.B. Saunders Co.: Philadelphia.)

Parkes J., Henzell R., and Pickles G. (1996). ‘Managing Vertebrate Pests: Feral Goats.’ (Australian Government Publishing Service: Canberra.)

Rainbolt, R. E. , and Coblentz, B. E. (1999). Restoration of insular ecosystems: control of feral goats on Aldabra Atoll, Republic of Seychelles. Biological Invasions 1, 363–375.
| Crossref | GoogleScholarGoogle Scholar | Reed W. C. (1982). Activity monitoring as a potential method of estrous detection in dairy goats. In ‘Proceedings of the Third International Conference on Goat Production and Disease, University of Arizona Tucson, January 10–15’. p. 561. (Dairy Goat Journal Publishing Co.: Scottsdale, AZ.)

Sharma, S. N. , Chatterjee, S. N. , and Kamboj, V. P. (1973). Sterilization of male goats by formaldehyde and some metallic salts. Indian Journal of Experimental Biology 11, 143–148.
| PubMed | Shelton M., and Klindt J. M. (1974). A simple method of male sterilization for use with sheep and goats. Texas Agricultural Experiment Station Research Reports. Sheep and Goat, Wool and Mohair October, pp. 10–11.

Smith M. C. (1997). Clinical reproductive anatomy and physiology of the doe. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 505–507. (W.B. Saunders Co.: Philadelphia.)

Taylor, D. , and Katahira, L. (1988). Radio telemetry as an aid in eradicating remnant feral goats. Wildlife Society Bulletin 16, 297–299.
Wolfe D. F. (1986). Surgical procedures of the reproductive system of the bull. In ‘Current Therapy in Theriogenology: Diagnosis, Treatment and Prevention of Reproductive Diseases in Small and Large Animals’. (Ed. D. A. Morrow.) pp. 353–379. (W.B. Saunders: Philadelphia.)

Wolfe D. F., and Baird A. N. (1997). Urogenital surgery in goats. In ‘Current Therapy in Large Animal Theriogenology’. (Ed. R. S. Youngquist.) pp. 494–498. (W.B. Saunders Co.: Philadelphia.)

Youngquist R. S. (Ed.) (1997). ‘Current Therapy in Large Animal Theriogenology.’ 1st edn. (W.B. Saunders Co.: Philadelphia.)