Effect Of Diets With Different Zinc Sources On Growth Performance And Immune Index Of Weanling Pigs

This study was conducted to evaluate the effect of dites with different zinc sources ongrowth performance, diarrhea index, economic efficiency, and immune function ofweanling pigs and to evaluate the possibility of using the AvailaZn, a organic zinc source,instead of ZnO. Setventy two crossbred weanling pigs (Landrace×Yorkshire) (BW=6.80±0.25 kg) at twenty-six±2 days old were assigned to one of three dietary treatments(four pigs per pen, half males and half females, six replicates per treatment) based onweight and litter origin. Before being weaned, they were fed by supplyment diets, and theywere injected by classical swine fever vaccine when they were at twenty two days old.Three treatments consisted of the following: 1) a corn-soybean meal-wheypowder-replacer whey powder diet (1.3% lysine) with a basal level of 100 mg/kg ofsupplemental Zn from ZnSO4 (control; contained 100 mg/kg total Zn); 2) control+2500mg/kg added Zn from ZnO; 3) control+250mg/kg added Zn from Available zinc; andeach piglet was raised in a single fold and water available at ad. The experimental period ofthis study was 28 days.The results were as follows:(1) There were not significantly (P＞0.05) difference among the three treatments aboutaverage daily gain, feed intake, feed/gain. But 250mg/kg AvailaZn treatment and2500mg/kg ZnO treatment have a greater enhancement in average daily gain, feed intake,feed/gain than control treatment.(2) Compared with control treatment, the weight of 250mg/kg AvailaZn and 2500mg/kgZnO treatment was enhanced by 9% and 7% respectively (P＜0.05).(3) compared with control treatment, at day 14 after they being weaned, plasma Znconcentration of 250mg/kg AvailaZn 2500mg/kg ZnO treatment are increased by 44% and42% respectively (P＜0.05); at day 28 after they being weaned, plasma Zn concentration of250mg/kg AvailaZn 2500mg/kg ZnO treatment are increased by 51% and 47% respectively (P＜0.05).(4) Compared with control treatment, at day 14 after they being weaned, ALP of 250mg/kgAvailaZn 2500mg/kg ZnO treatment are increased by 56% and 52% respectively (P＜0.05);at day 28 after they being weaned, ALP of 250mg/kg AvailaZn 2500mg/kg ZnO treatmentare increased by 55% and 46% respectively (P＜0.05).(5) On day 28 after piglet being weaned, 250mg/kg AvailaZn treatment and 2500mg/kgZnO treatment can increase IgG level greater than control treatment, compared with controltreatment, the IgG level of 250mg/kg AvailaZn treatment and 2500mg/kg ZnO treatmentwas increased by 54% and 38% respectively (P＜0.05), but between control treatment and2500mg/kg ZnO treatment there has no significant difference (P＞0.05).(6) compared with control treatment, at the 0～7 days trial period, diarrhea of 250mg/kgAvailaZn treatment and 2500mg/kg ZnO treatment is greater droped by 53% and 43%respectively (P＜0.05). at the 7～14 days trial period, diarrhea of 250mg/kg AvailaZntreatment and 2500mg/kg ZnO treatment is greater droped by 50% and 42% respectively(P＜0.05). at the 0～28 days trial period, diarrhea of 250mg/kg AvailaZn treatment and2500mg/kg ZnO treatment is greater droped by 50% and 40% respectively (P＜0.05).(7) skin of 250mg/kg AvailaZn is more slippery and shining than control and 2500mg/kgZnO treatment (P＜0.05).(8) 2500mg/kg ZnO treatment and 250mg/kg AvailaZn treatment have greater economicefficiency than control treatment. compared with control treatment, the income of2500mg/kg ZnO treatment and 250mg/kg AvailaZn treatment increases by 9RMB/pig and6.5RMB/pig respectively.(9) On day 28 after piglet being weaned, the classical swine fever serum antibody of250mg/kg AvailaZn treatment is increased greater than that of control treatment and2500mg/kg ZnO ((P＜0. 05).It can be concluded that it is feasible to feed 250mg/kg AvailaZn instead of 2500mg/kg ZnO in the pig starter diets, by which, the aim of increasing the growth performance,enhancing immunity and protecting the environm can be gained.