Abstract:
This research paper addresses the hypothesis that oxytocin (OT) could be released during suckling and during milking with and without the presence of a calf and that this release could be regulated by maternal behaviour. Plasma concentration patterns of OT and cortisol (CORT) were measured in six Tunisian dromedary camels during 2 suckling episodes, 2 manual milking episodes with calves beside the mother and 2 machine milking episodes without calves present. Various patterns of OT release were observed between each camel including specific two peak release patterns. Higher plasma OT concentrations were found during the suckling and hand-milking episodes with simultaneous suckling of calves, than during the machine milking episodes without calves. Exclusive mechanical milking episodes also evoked significant mean OT release, although greatly reduced compared to suckling and hand milking. The low basal levels and classical CORT release patterns suggested non-stressful management practices were used and there were very limited differences in udder stimulation between managements. The OT release induced by exclusive suckling and suckling together with hand-milking gives a reference point for what a good milk ejection stimulation is in camels. The important and specific reduction of OT release during machine milking without the calf present could be a physiological consequence of the maternal behaviour (selectivity for the own young) and to a lesser extent explained by a lower stimulation by machine milking.
摘要:
本研究论文提出了以下假设:催产素(OT)可以在哺乳过程中以及在有和没有小牛的情况下挤奶过程中释放,并且这种释放可能受母体行为的调节。在2次哺乳发作期间,在六只突尼斯单峰骆驼中测量了OT和皮质醇(CORT)的血浆浓度模式,2次人工挤奶,小牛在母亲旁边,2次机器挤奶,小牛不在场。在每个骆驼之间观察到各种OT释放模式,包括特定的两个峰释放模式。在哺乳和挤奶过程中发现较高的血浆OT浓度,同时哺乳小牛。而不是在没有小牛的机器挤奶事件中。独家机械挤奶事件也引起了重要的平均OT释放,虽然与哺乳和手工挤奶相比大大减少。较低的基础水平和经典的CORT释放模式表明使用了无压力的管理实践,并且管理层之间的乳房刺激差异非常有限。独家哺乳和哺乳以及手工挤奶引起的OT释放为骆驼中良好的排奶刺激提供了参考点。在没有小腿存在的情况下,机器挤奶过程中OT释放的重要且特定的减少可能是母体行为(对自己的幼仔的选择性)的生理后果,并且在较小程度上可以通过机器挤奶的较低刺激来解释。