Talafha A Q, Lafi S Q, Ababneh M M
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030, Irbid, 22110, Jordan.
Trop Anim Health Prod. 2009 Feb;41(2):161-70. doi: 10.1007/s11250-008-9171-0.
Fifty-three transitional-anestrus Awassi ewes, randomly assigned to three groups: fluorogestone acetate (FGA, n = 18), FGA-Prostaglandin (FGA-PGF, n = 18) and control (n = 17), were used to examine the effect of estrus synchronization protocols and steroid hormones concentrations on milk somatic cell count (SCC). Intravaginal FGA sponge was inserted for 13 days and 600 IU equine chorionic gonadotropin was administered for ewes of FGA and FGA-PGF groups at the time of sponge removal (day 0). In addition, 10 mg was administered to ewes of FGA-PGF group on day 0. Blood and milk samples were collected from all ewes on days -13, -6, 0, 1, 2, 7 and 14. Estradiol had significant positive correlation with the SCC during the periods of sponge insertion (P = 0.015, r = 0.235) and within two days (P = 0.063 r = 0.23) after sponge removal with no correlation with SCC of both udder halves during the luteal phase. Progesterone concentrations, on the other hand, had a significant positive correlation (P < 0.001; r = 0.420) with the SCC of both udder halves during the luteal phase of the experiment, but not during the periods of sponge insertion and expected estrus. SCC returned under the influence of endogenous progesterone on days 7 and 14 to pre-synchronization values. In conclusion, sheep milk SCC is affected significantly with induction of estrus and steroid hormones concentrations. However, peak SCC recorded during estrus was far below the upper limit of the current standard for normal milk. With the current standards for SCC of 1,000,000/ml as legal limit for abnormal milk control programs in sheep, estrus synchronization programs and the estrus status should not be considered when bulk-tank milk SCC is being investigated, but should be considered during the process of setting new standards.
选用53只处于过渡性乏情期的阿瓦西母羊，随机分为三组：醋酸氟孕酮组（FGA，n = 18）、醋酸氟孕酮 - 前列腺素组（FGA - PGF，n = 18）和对照组（n = 17），以研究发情同步方案和类固醇激素浓度对乳体细胞计数（SCC）的影响。给FGA组和FGA - PGF组的母羊阴道内插入含醋酸氟孕酮的海绵栓13天，并在取出海绵栓时（第0天）注射600国际单位的马绒毛膜促性腺激素。此外，在第0天给FGA - PGF组的母羊注射10毫克药物。在第 - 13、 - 6、0、1、2、7和14天从所有母羊采集血液和乳汁样本。在插入海绵栓期间（P = 0.015，r = 0.235）以及取出海绵栓后的两天内（P = 0.063，r = 0.23），雌二醇与SCC呈显著正相关，而在黄体期与两个乳房半侧的SCC均无相关性。另一方面，孕酮浓度在实验的黄体期与两个乳房半侧的SCC呈显著正相关（P < 0.001；r = 0.420），但在插入海绵栓期间和预期发情期与SCC无相关性。在第7天和第14天，SCC在内源性孕酮的影响下恢复到同步前的值。总之，绵羊乳SCC受发情诱导和类固醇激素浓度的显著影响。然而，发情期记录的SCC峰值远低于当前正常牛奶标准的上限。以目前每毫升1000000个细胞作为绵羊异常牛奶控制项目的法定限量标准，在调查奶罐奶SCC时不应考虑发情同步方案和发情状态，但在制定新标准的过程中应予以考虑。
