Centro de Investigación y Tecnología Animal-Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Segorbe, Spain.
Instituto de Ciencia y Tecnología Animal, Universitat Politècnica de València, Valencia, Spain.
Reprod Domest Anim. 2024 Oct;59 Suppl 3:e14584. doi: 10.1111/rda.14584.
Gonadotropin-releasing hormone (GnRH) -supplemented extenders have emerged as a welfare-orientated method to induce ovulation in the artificial insemination (AI) of rabbits. The main factor that limits the bioavailability of GnRH analogue on intravaginal administration is the proteolytic activity of enzymes present in rabbit seminal plasma. The use of GnRH analogues with higher biological potency would allow us to decrease their concentration in the seminal dose without compromising effectiveness. The current study was designed to assess the efficacy of various GnRH analogues concerning their ability to induce ovulation in rabbit AI. The base solution used for experimental extenders contained an aminopeptidase inhibitor. Four experimental groups were used, females from the Control group were induced to ovulate with an intramuscular administration of 1 μg of buserelin, while in the other three groups females received an intravaginal administration of 3.5 μg of buserelin (BUS), deslorelin (DES) or fertirelin (FER) within the seminal dose. Results showed that the ovulation frequency was similar in all groups studied. A concentration of 3.5 μg of the different GnRH analogues tested in this study showed similar potency in inducing ovulation in non-lactating females, yielding comparable results in terms of pregnancy rate at birth and prolificacy.
促性腺激素释放激素（GnRH）补充剂已成为一种以福利为导向的方法，可在兔人工授精（AI）中诱导排卵。限制 GnRH 类似物在阴道内给药时生物利用度的主要因素是兔精液中存在的酶的蛋白水解活性。使用具有更高生物学效力的 GnRH 类似物可以降低其在精液剂量中的浓度，而不会影响效果。本研究旨在评估各种 GnRH 类似物在诱导兔 AI 排卵方面的功效。实验用扩展剂的基础溶液含有氨肽酶抑制剂。使用了四个实验组，对照组的雌性通过肌肉内注射 1μg 的布舍瑞林诱导排卵，而在另外三个组中，雌性通过阴道内给予 3.5μg 的布舍瑞林（BUS）、地洛瑞林（DES）或 Fertirelin（FER）在精液剂量内。结果表明，所有研究组的排卵频率相似。在这项研究中测试的不同 GnRH 类似物的浓度为 3.5μg，在诱导非哺乳期雌性排卵方面具有相似的效力，在出生时的妊娠率和繁殖力方面产生相当的结果。
