Colakoglu Hatice Esra, Yazlik Murat Onur, Kaya Ufuk, Colakoglu Ekrem Cagatay, Kurt Serdal, Oz Burcu, Bayramoglu Rustem, Vural Mehmet Rifat, Kuplulu Sukru
Department of Obstetrics and Gynecology, University of Ankara, 06110, Ankara, Turkey.
Department of Biostatistics, University of Ankara, 06110, Ankara, Turkey.
J Vet Res. 2017 Dec 27;61(4):497-502. doi: 10.1515/jvetres-2017-0067. eCollection 2017 Dec.
The purpose of the current study was to evaluate the blood glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels under seasonal variations in dairy cows during transition period, and to assess the relationship between chosen reproductive parameters, GSH-Px, and MDA.
Holstein cows calving in January were assigned into winter group (n = 42), while cows calving in August were assigned into summer group (n = 42). Blood samples were collected from the jugular vein 21, 14, and 7 days before calving, at calving (0 day), and 7, 14, and 21 days after calving. Reproductive parameters obtained from farm records were evaluated.
In both groups of cows, GSH-Px activity decreased from 21 days before calving to day 0, and it gradually continued to increase until 21 days after calving. GSH-Px activity was higher in winter group compared to summer group during the transition period (P < 0.05). MDA levels in both groups increased over time starting from 21 days before calving to 0 day, but it gradually decreased thereafter. MDA levels were higher in summer group compared to winter group during the transition periods (P < 0.05). Summer group of cows showed higher intervals of calving-to-oestrus, calving-to-conception, and higher insemination index (P < 0.01). Negative correlation was recorded between GSH-Px and MDA during all examination days (P < 0.01). MDA levels correlated with calving to conception interval on day 21 before calving and day 0 (P < 0.01) and insemination index on day 0 and 21 days after calving (P < 0.01). GSH-Px activity was negatively correlated with calving to conception interval on day 21 before calving, day 0, and 21 days (P < 0.01) after calving. Negative correlation on day 21 before calving and day 0 was also determined between GSH-Px and insemination index (P < 0.01).
This study showed that blood oxidant and antioxidant levels have affected the fertility parameters in cows under seasonal variations.
本研究旨在评估围产期奶牛在季节变化下血液中谷胱甘肽过氧化物酶（GSH-Px）和丙二醛（MDA）水平，并评估所选繁殖参数、GSH-Px和MDA之间的关系。
1月份产犊的荷斯坦奶牛被分配到冬季组（n = 42），而8月份产犊的奶牛被分配到夏季组（n = 42）。在产犊前21天、14天和7天、产犊时（0天）以及产犊后7天、14天和21天从颈静脉采集血样。评估从农场记录中获得的繁殖参数。
在两组奶牛中，GSH-Px活性从产犊前21天到0天下降，并在产犊后21天之前逐渐持续升高。围产期冬季组的GSH-Px活性高于夏季组（P < 0.05）。两组中的MDA水平从产犊前21天到0天随时间增加，但此后逐渐下降。围产期夏季组的MDA水平高于冬季组（P < 0.05）。夏季组奶牛的产犊至发情间隔、产犊至受孕间隔更长，授精指数更高（P < 0.01）。在所有检查日，GSH-Px和MDA之间呈负相关（P < 0.01）。MDA水平与产犊前21天和0天的产犊至受孕间隔相关（P < 0.01），与产犊后0天和21天的授精指数相关（P < 0.01）。GSH-Px活性与产犊前21天、0天和产犊后21天的产犊至受孕间隔呈负相关（P < 0.01）。在产犊前21天和0天，GSH-Px与授精指数之间也呈负相关（P < 0.01）。
本研究表明，在季节变化下，血液中的氧化剂和抗氧化剂水平会影响奶牛的繁殖参数。
