氯霉素对肉鸡免疫功能的影响

按饲料的0.06％、0.1％、0.15％的比例添加氯霉素、饲喂2～60日龄的肉鸡,虽然对鸡白痢、禽伤寒等疾病有明显的抑制作用,减少死亡率。但对体液、细胞免疫功能、免疫器官、骨髓和红、白血球生成等呈现明显的抑制和损害,本试验初步表明,长期内服氯霉素可引起鸡的慢性应激反应。在正常的饲养条件下,氯霉素对肉鸡的生长增重既没有促进作用,也无明显的抑制现象。根据血液氯霉素浓度的测定表明,防治鸡疾病,饲料添加0.06％的氯霉素是有效的、毒性相对较小的剂量,但也不应长期服用。

EFFECT OF CHLORAMPHENICOL ON THE IMMUNITY IN BROILERS

A systematical test and examination of the cellular and humoral immunity, blood, immune organs and bone marrow confirmed that chlo-ramphenicol ( 0.06%, 0.1%, 0.15% ) in feed caused the inhibition and reduction of the immunity in broilers. The red and white blood cell counts decreased obviously. The Increase of the dose of chloramphenicol induced the more marked effects. The examination of blood glucose, fractionation of serum proteins, etc. indicated preliminarily that chloramphenicol caused the stress in broilers. The pathogenesis of stress in the young broilers may be different from the adult. The results show that the concentration of 0.06% chloramphenicol in feed is relatively lower toxicity and effective to control the diseases in broilers, if not used too long time.