肉用种鸡产蛋后期繁殖性能与氧化应激的相关性研究

如何控制产蛋高峰过后产蛋率下降过快是饲养肉用种鸡最关键的问题，氧化应激是引起母禽卵巢功能下降的主要因素之一，但氧化应激与肉用种鸡产蛋后期繁殖性能的关系尚不清楚，本试验随机选取连续产蛋15周和22周的种母鸡各6只，测定血清、肝脏和卵巢组织过氧化氢酶（CAT）、超氧化物歧化酶（SOD）、一氧化氮合酶（NOS）、一氧化氮（NO）、丙二醛（MDA）及谷胱甘肽过氧化物酶（GSH-Px）等6个抗氧化指标，以及卵巢功能的差异，结果显示产蛋15周和产蛋22周的种母鸡卵巢指数、等级前卵泡(大白卵泡和小黄卵泡）数量差异不显著；随着产蛋周龄的增加，种鸡机体氧化损伤程度加剧，种鸡血清和肝脏组织中的SOD，CAT，NO及GSH-Px显著或极显著降低（P<0.05或P<0.01)；产蛋15周种鸡肝脏中GSH-Px和CAT均显著高于产蛋22周（P<0.05)，而NOS和MDA则显著低于产蛋22周（P<0.05)；卵巢组织的6个抗氧化指标均差异不显著. 产蛋22周种鸡血清中的促性腺激素释放激素（GnRH）浓度与雌二醇（E2）浓度均显著低于产蛋15周样品组（P<0.05或P<0.01)，血清中GnRH浓度与血清SOD，CAT和NO水平之间存在显著正相关；血清中E2浓度与血清CAT和NO水平之间存在显著正相关；结果表明，肉用种鸡产蛋高峰过后卵巢机能衰退可能与血清和肝脏氧化损伤不断累积和加重相关.

Correlation between reproductive performance and oxidative stress index in late laying period of broiler breeder

How to maintain egg production persistency for broiler was the most critical problem in poultry industry. Oxidative stress was known to cause ovarian function decline in female chicken．The relationship between oxidative stress and reproductive performance in late laying period was still unknown．Six individuals at their laying age of 15 weeks and 22 weeks were randomly selected for the determination of 6 antioxidant index, including catalase (CAT), superoxide dismutase (SOD), nitric oxide synthase (NOS), nitric oxide (NO), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) among serum, liver and ovarian tissues. Our results showed that there were no significant differences in ovarian index and the number of prehierarchical follicles (big white follicles and small yellow follicles) between hens at 15 weeks and 22 weeks of laying age. SOD, CAT, NO and GSH-Px in serum and liver tissue of breeders were significantly decreased with the increase of laying week (P<0.05 or P<0.01). GSH-Px, and CAT in liver of breeders at 15 weeks of laying were significantly higher than those at 22 weeks of laying (P<0.05), while MDA and NOS were significantly lower than that at 22 weeks of laying (P<0.05). There were no significant differences in the 6 antioxidant indexes of ovarian tissue. Compared with the hens at 22 weeks of laying age, the concentration of both Gonadotrophin Releasing Hormone (GnRH) and Estradiol (E2) in serum were significantly higher at 15 weeks of laying age（P<0.05 or P<0.01). The Correlation anaylsis showed that there were significant positive correlation beween serum GnRH concentration and 3 antioxidant indexes (SOD, CAT and NO), between serum E2 concentration and 2 antioxidant indexes (CAT and NO). Our results indicated that the accumulation and aggravation of oxidative damage in serum and liver seems to relate to the decline of productive performance after laying peak.