Effects Of Interaction Of Vitamin A And Zinc Methionine On Blood Antioxidant Index，Immune Index And Intestinal Function In Weaning Piglets

The purpose of the thesis was to study the influences of different levels of VA and Zn Met in daily ration on the growth performance, serum biochemical index and antioxidant index, immune function and intestinal function of weaning piglets. Factorial design method of two factors and three levels was used in the experiment. Eighty-one healthy crossed piglets( Duroc×Landrace×Large white) weaned at 28 days of age were selected which were weighed( 7.94±0.62)kilograms and were randomly allotted to one of nine different treatments on the basis of the same weight and sex, and three replicates per treatment. Different dose of VA( 0、3 000、6 000 IU/kg)and Zn Met( 0、300、400 mg/kg)were added to the diet to feed them. The results of the study were followed:(1)The daily ration which was added with 3 000 IU/kg VA and 300 mg/kg Zn Met could meet the growth performance of weaned piglets at 35-56 days of age. Higher levels of VA and Zn Met could promote the growth of piglets better, while there was no significant effect with this level. The interaction of VA and Zn Met would appear after feeding.(2)The daily ration which were added with 6 000 IU/kg VA were better than the daily ration which were added with 3 000 IU/kg VA in weaned piglets, the content of 6 000 IU/kg VA added in daily ration was within the scope of normal use in weaned piglets at the age of 28 days; The content of 400 mg/kg Zn Met added in daily ration restrained the secretion of IL-2 in the later stage of test and the secretion of IL-4 in the early stage of test; the effect of interaction of VA and Zn Met was remarkable.(3)As for serum biochemical index, two levels of VA could improve the activity of AKP and reduce the content of UN significantly, while the influences on the content of CHO and TG and the activities of GPT and GOT were all non-significant. Two levels of Zn Met could both reduce the content of TG and UN and improve the activity of AKP significantly, but the influences on the content of CHO and the activities of GPT and GOT were all non-significant. The effect of interaction of VA and Zn Met was remarkable for the index of UN. As for serum antioxidant index, the additive amount of VA and Zn Met for young piglets was 6 000IU/kg and 300mg/kg separately; the additive amount of VA and Zn Met for older piglets was 6 000IU/kg and 400mg/kg separately; as for the index of MDA, the effect of interaction of VA and Zn Met was remarkable.(4)VA and Zn Met can both improve the intestinal villus height and villus width and reduce the intestinal crypt depth of weaned piglets significantly. The addition of VA or Zn Met could improve the activities of intestinal disaccharidase, and the effect of VA was more remarkable.