甲砜霉素对肉鸡睾丸组织结构的影响

Poisoning Effect of Thiamphenicol on Testis Morphology in Broilers

将152只4日龄雄性AA+肉鸡随机分为4组,每组38只,分别在饲料中添加0(对照组)、500(试验Ⅰ组)、1 000(试验Ⅱ组)、1 500 mg/kg(试验Ⅲ组)的甲砜霉素,自由采食,试验期2周,对睾丸进行病理形态学观察。2周后测量体重、睾丸重、睾丸脏器系数,并作睾丸石蜡切片测量曲精细管面积和观察甲砜霉素对肉鸡睾丸的病理组织学影响。结果表明,各试验组肉鸡体重和曲精细管面积以及试验Ⅱ、Ⅲ组试验鸡的睾丸重极显著低于对照组(P<0.01),试验Ⅰ组试验鸡的睾丸重和睾丸脏器系数极显著大于对照组(P<0.01);各试验组肉鸡曲精细管出现不同程度的生精细胞数量减少,精原细胞和睾丸支持细胞发生水泡变性,甚至坏死,结缔组织增生。结果表明,用甲砜霉素添加量500 mg/kg及以上的饲料持续饲喂肉鸡,可对肉鸡的睾丸造成损伤,并且这种损伤在一定范围内存在显著的剂量效应关系。

152 AA＋ male broilers at four-day-old were randomly divided into four treatments and fed on diets with different levels of thiamphenicol such as 0 mg/kg （control）,500 mg/kg（group Ⅰ）,1 000 mg/kg（group Ⅱ）,and 1 500 mg/kg （group Ⅲ） for 2 weeks for studying the poisoning effect of thiamphenicol on testis morphology in broolers. After 2 weeks,the body weight,testis weight,testis organ coefficient,seminiferous tubule area and some pathological change of the testis were measured and observed. The results showed that the body weight and seminiferous tubule area of three treated groups and the testis weight of group Ⅱ and Ⅲ were significant lower than those of control groups （P0.01）. The testis weight and testis organ coefficients of group Ⅰ were significant higher than those of control groups （P0.01）. The germ cells in the seminiferous tubules of three treated groups decreased at different degrees. The spermatogonia and sertoli cells were observed blister degeneration or even necrosis and desmoplastic. It indicated that the testis of broilers might be injured when fed with thiamphenicol above 500 mg/kg weight,and the damage degrees maybe correlated to thiamphenicol dosage in a certain extent.