高、低脂系肉鸡睾丸组织形态和氧化应激水平比较分析

Comparative analysis of testicular histomorphology and oxidative stress level between fat and lean broilers

研究旨在比较高、低脂系肉鸡睾丸组织形态和氧化应激水平差异。以高、低脂系第24世代27和36周龄肉种公鸡为试验材料,利用HE染色观察睾丸组织中曲细精管生精上皮结构,根据曲细精管面积、生精上皮厚度及Johnsen评分评估睾丸生精功能;利用试剂盒检测睾丸组织中氧化应激产物丙二醛含量及抗氧化酶(过氧化氢酶、总超氧化物歧化酶和谷胱甘肽过氧化物酶)活性。结果表明,27和36周龄高脂系肉鸡腹脂重和腹脂率显著高于低脂系;36周龄高脂系肉鸡睾丸重和睾丸比率显著高于低脂系;27和36周龄高脂系肉鸡睾丸中生精细胞脱落且排列紊乱,曲细精管内出现“脂肪样空泡”,曲细精管面积、生精上皮厚度、Johnsen评分显著低于低脂系;27和36周龄高脂系肉鸡睾丸组织中过氧化氢酶和总超氧化物歧化酶活性显著低于低脂系,丙二醛含量显著高于低脂系。以上结果表明,高脂系肉种公鸡腹脂沉积过多可能导致睾丸氧化应激水平升高,引起曲细精管生精上皮结构受损和生精功能下降。

The study aimed to compare the differences in testicular histomorphology and oxidative stress level between fat and lean broilers.The fat and lean breeder roosters from the 24th generation of the Northeast Agricultural University broiler lines divergently selected for abdominal fat content at 27 and 36 weeks of ages were used as experimental materials.The seminiferous epithelium structure of the seminiferous tubules of testicular tissue was observed by HE staining of paraffin section.Testicular spermatogenic function was assessed based on the area of the seminiferous tubules,thickness of the seminiferous epithelium and Johnsen score.The amount of oxidative stress product malondialdehyde(MDA)and the activity of antioxidant enzymes,including catalase(CAT),total superoxide dismutase(TSOD)and glutathione peroxidase(GSH-PX)in testicular tissue,were detected according to the instructions of the kits.The results showed that the abdominal fat weight and abdominal fat percentage of fat roosters were significantly higher than those of the lean roosters at 27 and 36 weeks of ages,and the testicular weight and testicular ratio of fat rooster were significantly higher than those of the lean roosters at 36 weeks of age.In the fat roosters,the spermatogenic cells were shedded and distributed disorderly in testicular tissue,"fat like vacuoles"appeared in the seminiferous tubules.The area of seminiferous tubules,thickness of seminiferous epithelium and Johnsen score of fat roosters were significantly lower than those of lean roosters at 27 and 36 weeks of ages.The activities of CAT and T-SOD in testicular tissue of fat roosters were significantly lower than those of the lean roosters,and the content of MDA was significantly higher than that of the lean roosters at 27 and 36 weeks of ages.In summary,the results of this study indicated that excessive abdominal fat deposition in the fat broiler breeder roosters might cause an increased in testicular oxidative stress levels,leading to damage to the structure of the seminiferous epithelium in the seminiferous tubules and decrease in spermatogenic function.