Effects of fermented feed on production performance,nutrient apparent digestibility,rumen fermentation characteristics and meat quality of fattening Hu sheep
[Objectives]This experiment was conducted to investigate the effects of different proportions of fermented feed in diets on rumen fermentation characteristics,nutrient apparent digestibility,performance and meat quality of fattening Hu sheep.[Methods]A total of 70 healthy Hu-sheep about 6 months old with similar body weight(30.86±4.50)kg were randomly divided into 5 groups(n= 14).The basal diet in each group was supplemented with 0%(control group),2%,4%,6%and 8%fermented feed(beneficial bacteria content≥1×108 CFU·g-1),respectively.Rumen fluid was collected at 45 d.During the trial period from 43 days to 45 days,dietary and fecal samples were collected to determine nutrient apparent digestibility.The growth performance indexes were measured according to the feed intake and initial and final weight during the test period.At the end of the experiment,3 fattening sheep were randomly selected from each group to be slaughtered for the determination of carcass traits and meat quality.[Results]The average daily gain(ADG)of 6%fermented feed supplemental level significantly increased(P<0.05),the ratio of feed to gain(F/G),average daily feed intake(ADFI)and dry matter intake(DMI)significantly decreased(P<0.01).When the fermented feed supplemental level was 8%,the slaughter percentage significantly increased compared with the control group(P<0.05).The nutrient apparent digestibility indexes significantly increased when 2%and 4%fermented feed were added(P<0.05).Different proportions of fermented feed had no significant effects on the contents of ammonia nitrogen(NH3-N),bacterial protein(BCP),acetic acid,butyric acid,ratio of ethylene to propylene total volatile fatty acid(TVFA)and meat quality of fattening sheep(P>0.05),but at 6%fermented feed supplemental level,pH value significantly decreased(P<0.05),and propionic acid significantly increased(P<0.05).[Conclusions]The supplementation of 6%fermented feed can improve nutrient apparent digestibility and performance of fattening Hu sheep,and has a positive effect on improving rumen fermentation characteristics.