Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA.
Theriogenology. 2010 Sep 15;74(5):733-40. doi: 10.1016/j.theriogenology.2010.03.026. Epub 2010 Jun 8.
Immunization against GnRH has been proven effective for boar taint removal, and long-term treatment with GnRH analogues has been shown to suppress GnRH dependent reproductive processes in several species. This study was conducted to treat boars (n = 5) with Suprelorin, i.e., an implant that contains 4.7 mg of the long-acting GnRH analogue deslorelin, and to test the effects on sexual function. Insertion of the implant occurred at the age of 5 weeks and animals were observed until market age at 26-27 weeks. Surgically castrated (n = 4) and intact boars (n = 3) served as controls. Testes growth was markedly reduced and steroidogenesis (testosterone, estrone, estrone sulphate, estradiol 17beta) as well as spermatogenesis suppressed in 4 of 5 GnRH treated boars, respectively. The remaining fifth boar resumed testes growth after week 17 of age and had high hormone concentrations when tested at weeks 26 and 27. Restoration of spermatogenesis was observed at 34 weeks of age. There were no effects of treatment on general health, nor were there local inflammatory reactions. Results indicate that suppression of sexual functions in boars due to long-term treatment with the GnRH agonist deslorelin through an implant such as Suprelorin is possible and can last for several months up to market age; thus it has potential as an alternative to other methods used for boar taint removal. Because the maximum duration of suppression seems to vary between boars, further studies are necessary to refine the treatment.
针对 GnRH 的免疫接种已被证明可有效去除公猪异味，并且长期使用 GnRH 类似物已被证明可抑制几种物种中依赖 GnRH 的生殖过程。本研究旨在用 Suprelorin（一种含有 4.7 毫克长效 GnRH 类似物 deslorelin 的植入物）治疗公猪，并测试其对性功能的影响。植入物在 5 周龄时插入，动物观察至 26-27 周龄的市场年龄。手术去势（n=4）和未去势公猪（n=3）作为对照。5 头 GnRH 处理的公猪中，有 4 头的睾丸生长明显减少，甾体生成（睾酮、雌酮、雌酮硫酸盐、雌二醇 17β）和精子发生受到抑制，而其余的第 5 头公猪在 17 周龄后恢复了睾丸生长，并在 26 周和 27 周时测试时具有较高的激素浓度。在 34 周龄时观察到精子发生的恢复。治疗对一般健康没有影响，也没有局部炎症反应。结果表明，通过植入物（如 Suprelorin）长期使用 GnRH 激动剂 deslorelin 抑制公猪的性功能是可能的，并且可以持续数月至市场年龄；因此，它有潜力替代其他用于去除公猪异味的方法。由于抑制的最大持续时间似乎在公猪之间存在差异，因此需要进一步研究来完善治疗方法。
