Comin A, Peric T, Montillo M, Cappa A, Marchi V, Veronesi M C, Prandi A
Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy.
Center for Biomedical Science and Engineering, University of Nova Gorica, Nova Gorica, Slovenia.
Reprod Domest Anim. 2017 Aug;52(4):632-639. doi: 10.1111/rda.12959. Epub 2017 Apr 4.
The aim of this research has been to evaluate the presence of anomalies in the ovarian cycle activity during postpartum and to verify whether 72-hr dietary fasting during the dominance phase, the phase before ovulation, might modify the ovarian follicle population. The presence of anomalies in ovarian cycle activity has been evaluated in 30 Italian Friesian cows starting from 20 days postpartum until 211 days of lactation. Long oestrus and brief dioestrus or scarce luteal activity have been the main anomalies found through measuring progesterone concentrations in the whey. Until 100 days of lactation, the BCS values of the problematic animals have been significantly lower than those in animals with normal ovarian activity. After 100 days of lactation, the ovarian anomalies continued to appear despite the fact that all the animals have reached comparable BCS values. Starting from the results of this trial, the effect of 72-hr dietary fasting on dominant follicles has been studied in six cows. Ultrasonography revealed that the diameter of the follicles at 71 days postpartum has been significantly lower than at 181 days. A 72-hr dietary restriction at 101 and 211 days postpartum did not affect the size of the dominant follicle. However, at 101 days postpartum, half of the animals presented follicular cysts. The effect of fasting differed if the animal has been in early postpartum or 211 days of lactation. Further researches are necessary to understand how different metabolic conditions can modify the follicular population but on the other hand the study shows the utility for farmers and field veterinarians of monitoring the resumption of the ovarian cycle postpartum through the whey progesterone concentrations.
本研究的目的是评估产后卵巢周期活动中异常情况的存在，并验证在优势期（排卵前阶段）进行72小时禁食是否会改变卵巢卵泡数量。从产后20天至泌乳211天，对30头意大利弗里生奶牛的卵巢周期活动异常情况进行了评估。通过测量乳清中的孕酮浓度发现，长发情期和短暂的间情期或黄体活动不足是主要的异常情况。在泌乳100天之前，有问题动物的体况评分（BCS）值显著低于卵巢活动正常的动物。泌乳100天后，尽管所有动物的BCS值已达到可比水平，但卵巢异常情况仍继续出现。基于该试验结果，对6头奶牛研究了72小时禁食对优势卵泡的影响。超声检查显示，产后71天卵泡直径显著低于181天。产后101天和211天进行72小时饮食限制并未影响优势卵泡的大小。然而，在产后101天，一半的动物出现了卵泡囊肿。禁食的影响因动物处于产后早期还是泌乳211天而有所不同。需要进一步研究以了解不同的代谢状况如何改变卵泡数量，但另一方面，该研究表明，对农民和现场兽医而言，通过乳清孕酮浓度监测产后卵巢周期的恢复是有用的。
