Kafi Mojtaba, Ghaemi Mehran, Azari Mehdi, Mirzaei Abdolah, Azarkaman Samad, Torfi Yusof
Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
Front Vet Sci. 2021 Apr 23;8:670121. doi: 10.3389/fvets.2021.670121. eCollection 2021.
The current study aimed to determine the effects of the preovulatory follicular fluid (FF) of normal heifer (NH) and repeat breeder cows with subclinical endometritis (SCE) or without (nSCE) on oocyte maturation (Experiment 1) and fertilization rates (Experiment 2). Moreover, the pattern of gene expression of cumulus oocyte-complexes was evaluated in Experiment 1. In Experiment 1, nuclear maturation in the nSCE group was higher, compared to that in the SCE group ( = 0.05). In addition, the oocyte nuclear maturation in the normal heifer was significantly higher, in comparison to that of SCE groups ( < 0.05). Furthermore, the mean percentage of normal oocyte fertilization was higher in the nSCE group, compared to that in the SCE group ( < 0.05). The expressions of growth differentiation factor, steroidogenic acute regulatory, and follicle-stimulating hormone receptor, in the NH group were significantly higher, compared to those in SCE and nSCE groups ( < 0.05). Moreover, the expressions of all genes in the nSCE group were not significant, in comparison to those in the SCE group ( > 0.05). The supplementation of oocyte maturation medium with FF from pre-ovulatory follicles of repeat breeder cows resulted in less oocyte maturation and cumulus cell expansion. In conclusion, the lower fertility in RB cows could be ascribed to the lower oocyte maturation rate and less expression of , and in the cumulus-oocyte complexes.
本研究旨在确定正常小母牛（NH）以及患有或未患有亚临床子宫内膜炎（SCE）的屡配不孕母牛的排卵前卵泡液（FF）对卵母细胞成熟（实验1）和受精率（实验2）的影响。此外，在实验1中评估了卵丘卵母细胞复合体的基因表达模式。在实验1中，与SCE组相比，nSCE组的核成熟度更高（P = 0.05）。此外，与SCE组相比，正常小母牛的卵母细胞核成熟度显著更高（P < 0.05）。此外，与SCE组相比，nSCE组正常卵母细胞受精的平均百分比更高（P < 0.05）。与SCE组和nSCE组相比，NH组中生长分化因子、类固醇生成急性调节蛋白和促卵泡激素受体的表达显著更高（P < 0.05）。此外，与SCE组相比，nSCE组中所有基因的表达均无显著差异（P > 0.05）。用屡配不孕母牛排卵前卵泡的FF补充卵母细胞成熟培养基会导致卵母细胞成熟和卵丘细胞扩张减少。总之，屡配不孕母牛的较低繁殖力可能归因于较低的卵母细胞成熟率以及卵丘 - 卵母细胞复合体中生长分化因子、类固醇生成急性调节蛋白和促卵泡激素受体的表达减少。
