Effects Of Low Protein Diets Supplemented With Arginine And Arginine Activator Additive On The Production Performance,Intestinal Morphology And Microflora In Weaned Piglets

ABSTRACT:Two experiments were designed to study the effects of different protein levels of diets and Arg&AAA in diets on production performance, diarrhea rate, protein digestibility and serum biochemical indicators, intestinal morphology and microflora in weaned piglets.Experiment 1:We selected 200 weaned piglets which were in good health and had the similar weight,then divided them into 5 treatments randomly with 4 replicates each treatment and 10 weaned piglets per replicate.The protein level of the control group diet was 21.5%,and the protein level of group 1,2,3,4 was 20.5%, 19.5%,18.5%,17.5% respectively.All diets were formulated on the basis of corn-soybean meal diet according to the 2012 American NRC swine nutrition guide, and the LPD met the requirements of the ratio of ideal amino acid in the piglets by adding synthetic amino acids. The Transition before the experiment was 5 days, and the experiment lasted 21 days. The results indicated:(1) The average daily feed intake (ADFI), average daily gain (ADG) and protein digestibility of weaning piglets between the groups of different protein levels had no difference (P>0.05),the feed:gain(F:G) of the diets (CP=19.5%,18.5%)were reduced significantly compared with the diets (CP=21.5%,17.5%) (P<0.05), the diarrhea rate of diet (CP=17.5%) was reduced significantly compared with the diets (CP=21.5%) (P<0.05).(2)The concentration of serum urea nitrogen and the activity of glutamic-pyruvic transaminase,alkaline phosphatase of the weaning piglets fed the diets (CP=18.5%, 17.5%) were reduced significantly (P<0.05), also the concentration of serum IgA、 IgG were significantly increased(P<0.05), the diet (CP=17.5%) reduced serum the concentration of cholesterol significantly (P<0.05), other diets had no effect on serum biochemical indices (P>0.05).Experiment 2:We selected 240 weaned piglets which were in good health and had the similar weight,then divided them into 6 treatments randomly with 4 replicates each treatment and 10 weaned piglets per replicate. The Transition before the experiment was 5 days, and the experiment lasted 21 days. The control group was fed based diet, whose protein level was 18.5%.The other 5 groups were fed the based diet adding 0.2%Arg,0.4% Arg,0.6% Arg,0.03%AAA and 0.06% AAA respectively. All diets were formulated on the basis of corn-soybean meal diet according to the 2012 American NRC swine nutrition guide.The results indicated:(1) The LPD adding different levels of Arg and AAA all significantly increased the ADFI and ADG of the weaned piglets(P<0.05),but only the group adding 0.4% Arg reduced the F:G significantly of the weaned piglets(P<0.05).(2) The group adding 0.4% Arg,0.03%AAA significantly reduced the diarrhea rate of the weaned piglets(P<0.05). The group adding 0.4% Arg and 0.03%AAA increased the protein digestibility of the weaned piglets significantly (P<0.05). (3) The group adding 0.2% Arg improved the serum total protein significantly(P<0.05), the group adding 0.03% AAA reduced the serum urea nitrogen significantly(P<0.05), the diets adding different levels of Arg and AAA all increased the serum IgA significantly(P<0.05). But all groups in serum albumin, globulin, albumin/globulin,glucose, glutamic-pyruvic transaminase,glutamic oxalacetic transaminase and alkaline phosphatase, total cholesterol, triglyceride,high density lipoprotein,low density lipoprotein, IgG and IgM had no no difference(P>0.05).(4) The groups adding 0.4% Arg and 0.03%AAA improved the villus height (VH) and villus height/crypt depth(VH/CD) of duodenum jejunum and ileum significantly(P<0.05), improved villus width(VW) of Jejunum and ileum significantly(P<0.05),significantly reduced the intestinal CD of the duodenum jejunum and ileum(P<0.05),but had no effect on VW of duodenum (P>0.05);The group adding 0.06% AAA improved the VH of duodenum and ileum(P<0.05),improved the VW of ileum(P<0.05),significantly reduced the intestinal CD of ileum(P<0.05), significantly improved the VH/CD of duodenum, jejunum and ileum(P<0.05).(5) In addition to that the group adding 0.2% Arg had no effect on e. coli of caecum,All groups adding Arg and AAA significantly reduced the number of e. coli in caecum,colon and rectum(P< 0.05). The group adding 0.4% Arg significantly increased the number of lactic acid bacteria of the caecum, colon and rectum (P<0.05). The group adding Arg 0.6% arginine significantly increased the number of lactic acid bacteria of the colon and rectum (P<0.05). The group adding 0.2% Arg significantly increased the number of lactic acid bacteria of rectal (P<0.05). The group of AAA had no effect on the number of lactic acid bacteria in caecum, colon and rectum (P>0.05).