Study On Effects Of Salinomycin And Colistin Incorporated In Diets Of Weanling Pigs

Experiment 1:Study on Effects of salinomycin incorporated in diets of weanling pigsSeventy two 35-days-Old cross-bred (Duroc×Landrace×Large White)weaned pigs with initial weight of 7.89±0.56kg were randomly allotted to three treatments with four replicates per treatment and six pigs per pen(three gilts and three barrows) at similar initial body weight.Basal diet was fed to control group .Basal diet+60mg/kg salinomycin of wheat-bran carrier(12%)> 60mg/kg salinomycin of zeolite carrier(12%) were supplied to other experimental groups,respectively.The results indicate that weight gain of weanling pigs fed salinomycin with inorganic carrier is significantly higher than the control(.P<0.05). Feed conversion ratio of weanling pigs was significantly improved by the supplementation of salinomycin.Diarrhea rate was decreased(p<0.05).The supplementation of salinomycin produced insignificant effects on apparent digestibilility of dietary energy, fibre, Ca and P. Salinomycin with inorganic carrier increased the digestibility of DM and CP significantly(p<0.05).Experiment 2:Effects of salinomycin combined with different colistin on growth performance of weanling pigs108 cross-bred weaned pigs(D×L×LW) weighed at 8.32±0.55kg were randomly allotted to three different dietary treatments with six replicates per treatment and six pigs per pen(three gilts and three barrows) at similar initial body weight.Control pigs were fed basal diet with 60mg/kg salinomycin(zeolite carrier, 12%) and the pigs of the other two treatments were fed basal diet+60mg/kg salinomycin(zeolite carrier, 12%)+20mg/kg import colistin,basal diet+60mg/kg salinomycin(zeolite carrier, 12%)+20mg/kg local colistin.The results of the experiment indicate that combined use of salinomycin and colistin improved daily weight gain and feed conversion ratio of weanling pigs(P>0.05).Diarrhea rate was dropped(P>0.05).There is no significant difference in the effects of growth promotion between import and local colistin.ADF digestion was significantly increased by addition of colistin (P<0.05).Experiment 3: Study of the Optimum ratio of salinomycin and colistin for weanling pigs120 cross-bred weaned pigs(D×L×LW) weighed at 8.53±0.65kg were randomly allotted to five different dietary treatments with six replicates per treatment and four pigs per pen(two gilts and two barrows) to investigate effects of the supplementation of salinomycin and colistin in different ratio on performance and nutrient digestibility of weanling pigs.The diet of control pigs contained no antibiotics. 60mg/kg salinomycin+10mg/kg ,+15mg/kg,+20mg/kg,+30rng/kg colistin were fed to the pigs of the other four treatments.The results indicate that colistin at 15mg/kg produced optimum growth performance.Joint use of Salinomycin and colistin increased total aerobes in different section of intestine and decreased lactobacilli in the middle and latter section of jejunum and caecum.Growth of E.coli and salmonella was significantly inhibited(P<0.05). supplementation of colistin increased thenumber of Villi in jejunum and ileum and decreased height of villi in jejunum.