摘要
实验采用2×3因子设计,选用一日龄艾维因肉仔鸡288只,分6个处理,下设4个重复,各重复含12只鸡,对2,700IU/kg、20,000IU/kg 两个剂量和粉剂、进口乳剂、自制乳剂三个剂型的维生素 A(V.A)对家禽免疫功能的影响及其机制进行了研究。结果发现:1.高剂量 V.A 有使胸腺、脾脏、法氏囊等免疫器官的绝对重量增加的趋势,但统计差异不显著(P>0.05)。2.高剂量 V.A 有提高血清抗体滴度的趋势,但统计差异不显著(P>0.05),而乳剂处理极显著优于粉剂(P<0.01)。3.高剂量 V.A 有提高血浆淋巴 T 细胞百分比的趋势,但差异不显著(P>0.05);在绝对值上,乳剂优于粉剂,而统计上无差异(P>0.05)。4.大剂量添加 V.A 显著提高血浆中 CAMP(环——磷酸腺苷)的浓度(P<0.05),但乳剂处理的血浆 CAMP 含量显著低于粉剂处理的相应值(P<0.05)。5.V.A 的剂型剂量二因素对体增重、饲料效率、死亡率等无显著影响(P>0.05),但大量添加 V.A 极显著地提高鸡只肝中 V.A 的浓度(P<0.01)。6.V.A 对鸡只免疫功能的影响与血浆中 CAMP 有关。
288 day—old avian broiler chickes were divided into 6 groups each with a duplicates,assigned to a 3×2 factoral experiment i.e,3 sourses of Vitamin A.conventional powder,imported water dispersible powder,self prepared water—dispersible powder at 2 dosage levels(2,700IU/kg,20,000IU/ kg),raised on a corn—soy diet to 6 weeks of age. Results were as follows: 1.On the high Vitamin A dosage,thymas,spleen bursa fabricius absolute weights and plasma T—lymphatic cell percentage trended to increase but did not reach statistical significance(P>0.05). 2.Water—dispersible powder was non—statistically superior to conventional powder. 3.The CAMP content in plasma was significintly higher(P<0.05)on high Vitamin dosage,although it was much lower with the water—disper- sible powder as against conventional powder(p<0.05). 4.Neither dosage nor sourse of Vitamin A exerted any effect on body weight gain,feed eoversion or mortality(P>0.05). 5.The increasing trend in immune respouse seemed to be related to the CAMP in plasma,although powder sourse and dosage level seemed to affect immulogical functions differently.
