Kurykin J, Waldmann A, Tiirats T, Kaart T, Jaakma U
Department of Reproductive Biology, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia.
Reprod Domest Anim. 2011 Apr;46(2):253-60. doi: 10.1111/j.1439-0531.2010.01652.x.
The objectives of the study were to evaluate the morphological quality of oocytes in repeat breeder and early lactation cows and to determine the possible associations between the quality of oocytes and a range of blood metabolites. Oocyte quality and a range of metabolites were compared between 29 repeat breeder and 13 early lactation cows. The yield of oocytes from the repeat breeders was lower than that from the early lactation cows (4.4 ± 0.2 vs 5.4 ± 0.6, p < 0.05). Percentages of abnormal oocytes for the repeat breeders and the early lactation cows were 52.5% and 37.9%, respectively (p < 0.001). An excess of abnormal oocytes to normal was found in 55.2% of the studied repeat breeders (65.8% vs 34.2%, p < 0.05). Total protein, glucose and aspartate aminotransferase did not differ (p > 0.05) between the repeat breeders with an excess of abnormal oocytes (81 ± 1.0 g/l, 3.5 ± 1.0 mmol/l and 68.5 ± 3.7 U/l), those with the prevalence of normal oocytes (84 ± 1.0 g/l, 3.6 ± 0.1 mmol/l and 73.2 ± 3.5 U/l) and the early lactation cows (83 ± 2.0 g/l, 3.7 ± 0.1 mmol/l and 74.5 ± 3.6 U/I). The repeat breeders with an excess of abnormal oocytes had higher (p < 0.05) urea (5.2 ± 0.2 mmol/l) level than in those with the prevalence of normal oocytes (4.8 ± 0.2 mmol/l) and the early lactation cows (4.7 ± 0.2 mmol/l). A trend for higher total cholesterol and lactate dehydrogenase activity was found in the repeat breeders with an excess of abnormal oocytes. In conclusion, it is suggested that possible causes of repeat breeding in dairy cows may include impaired oocytes. An excess of abnormal oocytes in the repeat breeder cows was associated with elevated blood plasma levels of urea.
本研究的目的是评估屡配不孕奶牛和泌乳早期奶牛卵母细胞的形态质量，并确定卵母细胞质量与一系列血液代谢物之间可能存在的关联。对29头屡配不孕奶牛和13头泌乳早期奶牛的卵母细胞质量及一系列代谢物进行了比较。屡配不孕奶牛的卵母细胞产量低于泌乳早期奶牛（4.4±0.2对5.4±0.6，p<0.05）。屡配不孕奶牛和泌乳早期奶牛的异常卵母细胞百分比分别为52.5%和37.9%（p<0.001）。在55.2%的研究屡配不孕奶牛中发现异常卵母细胞多于正常卵母细胞（65.8%对34.2%，p<0.05）。异常卵母细胞过多的屡配不孕奶牛（81±1.0 g/l、3.5±1.0 mmol/l和68.5±3.7 U/l）、正常卵母细胞占优势的屡配不孕奶牛（84±1.0 g/l、3.6±0.1 mmol/l和73.2±3.5 U/l）以及泌乳早期奶牛（83±2.0 g/l、3.7±0.1 mmol/l和74.5±3.6 U/I）之间的总蛋白、葡萄糖和天冬氨酸转氨酶无差异（p>0.05）。异常卵母细胞过多的屡配不孕奶牛的尿素水平（5.2±0.2 mmol/l）高于正常卵母细胞占优势的屡配不孕奶牛（4.8±0.2 mmol/l）和泌乳早期奶牛（4.7±0.2 mmol/l）（p<0.05）。在异常卵母细胞过多的屡配不孕奶牛中发现总胆固醇和乳酸脱氢酶活性有升高趋势。总之，建议奶牛屡配不孕的可能原因可能包括卵母细胞受损。屡配不孕奶牛中过多的异常卵母细胞与血浆尿素水平升高有关。
