Fonseca J F, Torres C A A
Embrapa Caprinos, Laboratório de Reprodução Animal, Campo Experimental Coronel Pacheco, Rodovia MG 133, km 42, CEP 36.155-000 Coronel Pacheco-MG, Sobral, Brazil.
Reprod Domest Anim. 2005 Dec;40(6):495-9. doi: 10.1111/j.1439-0531.2005.00612.x.
The objective of this study was to investigate the effect of hCG administration 5 days after breeding on plasma progesterone (P4) concentration and reproductive performance of oestrous-induced nulliparous dairy goats. A total of 59 nulliparous goats (36 Alpine and 23 Saanen) received intravaginal sponges with 60 mg medroxyprogesterone acetate for 9 days plus 200 IU equine chorionic gonadotrophin (eCG) and 22.5 microg d-cloprostenol 24 h before sponge removal. After detection of oestrus (day of oestrus = day 0) and breeding, 49 females were randomly assigned, according to the breed, into two treatments (T1 and T2). In T1 (n = 25) and T2 (n = 24), animals received intramuscular injection of 1 ml of saline solution (control) or 250 IU hCG, respectively, 5 days after breeding. Plasma P4 concentration (ng/ml) was determined from blood sampled on days 0, 5, 7, 13, 17, 21, 28 and 45 after breeding. Animals were scanned by transrectal ultrasound (5 MHz probe) on days 35 and 70 after breeding for detection of pregnancy. Plasma P4 concentration did not differ (p > 0.05) between treatments in all days, but it was increased (p < 0.05) in Saanen than in Alpine goats from days 13 to 45. Pregnancy and parturition rates, litter size and gestation period were similar (p > 0.05) to treatments and breeds. Results of this study indicate that human chorionic gonadotrophin (hCG) administration 5 days after breeding did not significantly alter reproductive performance in dairy nulliparous goats and that plasma P4 differed between Saanen and Alpine goats.
本研究的目的是调查配种后5天给予人绒毛膜促性腺激素（hCG）对诱导发情的初产奶山羊血浆孕酮（P4）浓度和繁殖性能的影响。总共59只初产山羊（36只阿尔卑斯山羊和23只萨能山羊）接受含60mg醋酸甲羟孕酮的阴道海绵栓处理9天，在取出海绵栓前24小时给予200IU马绒毛膜促性腺激素（eCG）和22.5μg d-氯前列醇。在检测到发情（发情日=第0天）并配种后，根据品种将49只母羊随机分为两个处理组（T1和T2）。在T1组（n = 25）和T2组（n = 24）中，动物在配种后5天分别接受肌肉注射1ml生理盐水（对照组）或250IU hCG。在配种后的第0、5、7、13、17、21、28和45天采集血液样本，测定血浆P4浓度（ng/ml）。在配种后的第35天和70天，通过经直肠超声（5MHz探头）对动物进行扫描，以检测妊娠情况。在所有天数中，各处理组之间的血浆P4浓度没有差异（p>0.05），但从第13天到第45天，萨能山羊的血浆P4浓度高于阿尔卑斯山羊（p<0.05）。妊娠率、产仔率、产仔数和妊娠期在各处理组和品种之间相似（p>0.05）。本研究结果表明，配种后5天给予人绒毛膜促性腺激素（hCG）对初产奶山羊的繁殖性能没有显著影响，且萨能山羊和阿尔卑斯山羊的血浆P4浓度存在差异。
