Department of Animal Husbandry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 16521 Prague 6, Suchdol, Czech Republic.
Anim Reprod Sci. 2013 Nov 1;142(1-2):28-34. doi: 10.1016/j.anireprosci.2013.09.005. Epub 2013 Sep 16.
The objectives of this study were to evaluate the relationships among urea and acetone content in cows' cervical mucus (CM), its crystallization type (CT) and sperm survival (SS) after timed AI. Samples of CM were collected from 192 Holstein cows treated by Ovsynch(®) protocol. Analysis of the urea and acetone content for identification of the metabolic status, the arborization test for evaluation of insemination timing and the short-term heat test of SS for assessment of its suitability as a biological matrix were performed. The data set was analyzed by the GLM procedure using SAS(®). The results documented the existence of substantial differences in individual response to the Ovsynch(®) protocol causing insemination of 55.2% cows at an inappropriate time. The urea content was found as a possible indicator of a cow's metabolism and/or of insemination timing, concentrations of less than 500 mg/L corresponded (P<0.05-0.01) to the cows' expected response to timed AI. The greater the urea content, the greater the proportion of cows inseminated at an inappropriate time. Effects (P<0.05-0.01) of CT, urea and acetone content on SS were determined. The greatest values of SS were detected in cows with an expected response to precisely timed oestrus documented by the corresponding CT. Greater values of urea (>260 mg/L) and acetone (>5mg/L) negatively affected SS as well (P<0.05-0.01). The results confirmed that the accuracy of insemination timing can be affected by the metabolism intensity, just as CM quality directly influences sperm survival.
本研究旨在评估奶牛宫颈黏液（CM）中的尿素和丙酮含量与其结晶类型（CT）和精子存活（SS）在定时人工授精后的关系。该研究采集了 192 头荷斯坦奶牛经 Ovsynch（®）方案处理后的 CM 样本。对其进行尿素和丙酮含量分析以确定代谢状态，采用树状试验评估输精时间，采用短期 SS 热试验评估其作为生物基质的适宜性。使用 SAS（®）的 GLM 程序对数据集进行分析。结果记录了个别牛对 Ovsynch（®）方案的反应存在显著差异，导致 55.2%的牛输精时间不当。研究发现尿素含量可能是牛代谢和/或输精时间的指示物，浓度低于 500mg/L 与牛对定时人工授精的预期反应相关（P<0.05-0.01）。尿素含量越高，输精时间不当的牛的比例越大。还确定了 CT、尿素和丙酮含量对 SS 的影响（P<0.05-0.01）。具有精确发情期预期反应的牛（通过相应的 CT 确定）的 SS 值最大。尿素（>260mg/L）和丙酮（>5mg/L）含量较高也会对 SS 产生负面影响（P<0.05-0.01）。结果证实，输精时间的准确性可能会受到代谢强度的影响，就像 CM 质量直接影响精子存活一样。
