Effects Of Dietary Supplementation With Nucleotide On Growth Performance Of Weaned Piglets

With the promotion of the early weaning technology,the weaning stress of piglets has gradually become a serious problem in the modern pig farms.The livestock husbandry has always been searching the best feed additive that can replace the antibiotic due to the antibiotic resistance and residual problems.The study was conducted to explore the effect of the dietary supplementation with different levels of nucleotide or 1%yeast nucleotide on the growth performance,the utilization of nutrient,and blood parameters,and to provide a scientific theoretical basis for its application in the production of pigs.This study mainly contained three experiments:In trial 1,the effects of dietary supplementation with different levels of nucleotide or 1%yeast nucleotide on the growth performance and the utilization of nutrient were evaluated.Total 300 21-days old piglets(Duroc×LandracexLarge white)with similar weight,were randomly allocated to 5 groups with 6 replicates(n = 10,5 males and 5 females)in each group.CON group was defined as the control group fed basic diets,and other groups was defined as Y group,N1 group,N2 group and N3 group fed with the 1%yeast nucleotide,0.05%nucleotide,0.1%nucleotide and 0.2%nucleotide respectively.The results showed that:(1)In the end of the this experiment,compared with CON group,the ADG of N1,N2 and N3 groups were significantly increased by 13.12%,13.50%and 16.56%(P<0.05),and ADG of Y group increase by 10.06%(P>0.05).Comparing to the CON group,the F/G of Y,N1,N2 and N3 significantly decreased by 11.47%,8.92%,8.92%and 10.19%respectively(P>0.05).However,compared with the Y group,there no significantly difference of F/G in N1,N2 and N3 groups(P>0.05).(2)Comparing with the CON group,the rate of the utilization of EE,in Y,N1,N2 and N3 significantly increased 3.44%,4.58%,3.46%and 17.10%respectly(P<0.05).,the rate of P,GE and DM in group N3 was significantly increased(P<0.05).(3)Comparing to CON group,the ratio of diarrhea in the all treatment groups was remarkable decreased(P<0.05).The ration of death in all the treatment groups is 0%,except CON with 5%.In trial 2,the effects of dietary supplementation with different levels of nucleotide or 1%yeast nucleotide on the blood routine and blood biochemistry parameters have been researched.The experiment design was same as that of trial 1.The results showed that:(1)Comparing with CON group,the level of WBC and HCT were significantly decreased in N2 group(P>0.05).(2)The level of BUN,CRE in N1,N2 and N3 group was significant decreased lower than that of CON group(P<0.05).The level of AST in N1 group was significant lower than that of CON group.(3)The level of the HDL-C in Y,N1,N2 and N3 group was higher than that of CON group,but the level in Nl,N2 and N3 is lower than that of Y group(P>0.05).Meanwhile,no apparently effect was observed on the TG and TCHO(P>0.05).In trial 3,the effects of dietary supplementation with different levels of nucleotide or 1%yeast nucleotide on the blood immune parameters and blood antioxidant ability have been researched.The experiment design was same as that of trial 1.(1)Comparing to the CON group,the level of IgG in Y,Nl,N2 and N3significantly decreased by 28.01%,34.02%,21.58%and 37.98(P<0.05).(2)Comparing to the CON group,the level of TNF-a in N2 and N3 was significantly decreased by 36,03%and 36.59%(P<0.05).However,the different level of nucleotide and 1%yeast nucleotide has no remarkable effect on the IL-1?IL-2 and IL-10(P>0.05).(3)The N1 group showed apparent higher LSZ level than that of CON group,neverthless there was no notable difference among other treatment groups.And the level of C3 in N2 and N3 was significant higher than that of CON,meanwhile the level in N3 group was remarkable increased than Y group.(4)Comparing to the CON group,the content of MDA in N3 was significantly decreased by 35.63%(P<0.05).Moreover,the level of CAT in the N2,N3 group significantly increased by 128.74%and 177.97%comparing to the CON group,and the level in the N2,N3 group was remarkable increased by 168.14%and 218.20%respectively.In conclusion,diets supplementation with different level of nucleotide and 1%yeast nucleotide can improve the ADG,nutrient utilization and the blood antioxidant ability,and regulate the immunity.This study showed that the optimal dosage of nucleotide in weaned piglet dietary is 0.2%.