Effects of Different Probiotics on Growth Performance,Digestion and Metabolism and Immune Indexes of Calves
To study the effects of different probiotics supplementation in diets on growth performance,digestibility and metabolism,immune indexes and diarrhea of calves,42 Holstein calves aged 20 days were divided into 7 groups according to the principle of similar body weight and half male and half female,each group 6 calves.The control group was fed with basic diet.The experimental group was supplemented with 0.1%Bacillus subtilis,0.05%Bacillus subtilis,0.2%Lactobacillus,0.1%yeast,0.05%Enterococcus faecalis and 0.1%Bacillus licheniform is,respectively.The pre-feeding period was 10 days and the trial period was 75 days.The results showed:(1)at 105 days of age,the weight of the experimental group was higher than that of the control group,the body weight of calves in 0.2%Lactobacillus group and 0.05%Enterococcus faecalis group were higher than those in the control group(P<0.05),and at 60 days and 150 days of age,the physique of 0.2%Lactobacillus group was higher than that of the control group(P<0.05),daily weight gain of the 0.2%Lactobacillus group,0.1%yeast group,0.05%Enterococcus faecalis group,and 0.1%Bacillus licheniform is group was significantly higher than that of the 0.1%Bacillus sub-tilis group and control group(P<0.05)at 30~150 days of age.(2)At 105 days old,the dry matter,NDF,ADF,OM and NDF apparent digestibility of the 0.05%Enterococcus faecalis group and the 0.2%Lactobacillus group were significantly higher than the control group(P<0.05).At 105 days old,the NDF apparent digestibility of the 0.1%yeast group was significantly higher than the control group(P<0.01),and the ADF apparent digestibility was significantly higher than the control group(P<0.05).(3)At 60 and 105 days of age,the IgG content in the 0.2%Lactobacillus group and 0.05%Enterococcus faecalis group was significantly higher than the control group(P<0.01)and significantly higher than other experi-mental groups(P<0.05);At the age of 60 days,the IgM and IgA contents in the 0.05%Enterococcus fe-cal group and the 0.1%Bacillus licheniformis group were significantly higher than those in the control group(P<0.05).(4)The diarrhea frequency of 0.2%Lactobacillus group and 0.05%Enterococcus faeca-lis group was the lowest,and the fecal score was higher in the control group and 0.05%Bacillus subtilis group.These results showed that probiotics can promote the growth and development of weaned calves,especially Lactobacillus and Enterococcus faecalis;probiotics significantly improved the apparent digesti-bility and nitrogen metabolism of DM,OM,NDF and ADF in calves.Enterococcus faecalis,yeast and Lactobacillus were better than other probiotics in NDF and ADF;the addition of enterococcus faecalis can increase the content of immunoglobulin in calves,and probiotics can reduce the probability of diarrhea in calves,of which the lactic acid bacteria and Enterococcus faecalis have better effect.