Effects Of Aspergillus Oryzae Culture On The Performance And Rumen Function Of Hu Sheep

Aspergillus oryzae culture(AOC)are common fungal microecological agents,which can effectively regulate the animal gastrointestinal microecology and improve production performance,and have the characteristics of safety,high efficiency and no drug residues.They are often used as feed additives and widely used in ruminant production.In order to explore the effects of different feeding amount on growth performance,nutrient digestion and rumen fermentation of Hu sheep,determine its effect,appropriate addition amount and mechanism in production,and apply it to Hu sheep production more scientifically and reasonably,the following experiments were carried out:Trial 1: Effects of feeding amount of Aspergillus oryzae culture on growth performance and nutrient apparent digestibility of Hu sheepThe degradation rate of AOC in rumen was determined by in situ degradation;At the same time,feeding experiments were conducted to determine the effects of different amount on growth performance,nutrient apparent digestibility and energy and nitrogen utilization of fattening Hu lambs.32 fattening Hu lambs were selected according to their body weight(20.18 ± 1.89 kg)were randomly divided into 4treatment groups with 8 replicates in each group.Before morning feeding,each sheep in the experimental group was added with 10 g/d,20 g/d and 40 g/d AOC respectively.The pre-test period was 7 days and the normal test period was 42 days.The results show that:1.The degradation rate of AOC increased with the time of degradation,reaching90.18% after 48 hours,and the degradation rate gradually slowed down;The degradation rate of AOC in rumen was 10.23%,that of slow degradation part(b)72.14%,and that of slow degradation part(c)was 0.25% /h and effective degradation rate(ED)was 68.41%;2.There was no significant difference in the initial body weight(IBW),final body weight(FBW),DMI and feed to weight ratio of Hu sheep fed with AOC(P >0.05);ADG increased linearly with the increase of AOC(P = 0.047).Compared with CON,ADG increased by 3.45%,6.90% and 13.79% with the increase of AOC;3.DM intake increased linearly with the increase of AOC(P < 0.05).Compared with CON,DM intake increased by 8.16% at 40 g/d;There was no significant difference in the apparent digestibility of DM,OM,CP,NDF and ADF among the treatment groups(P > 0.05);4.The total energy intake increased linearly with the increase of AOC(P < 0.05).The fecal energy and energy digestibility of the 40 g/d group were significantly higher than those of the control group and the 10 g/d group(P < 0.05).Trial 2: Effects of feeding amount of Aspergillus oryzae culture on rumen fermentation and microflora of Hu sheepSixteen adult castrated fattening Hu sheep in good condition with permanent rumen fistula were selected in a randomized block design(64.62 ± 5.83 kg)were randomly divided into four groups.The basal diet and AOC were fed the same amount as the experiment 1.The experiment was repeated for two periods,with 8 replicates in each treatment group.Each period included 7 days of transition,14 days of prefeeding and 7 days of sample collection.The results show that:1.The 24 h DM degradation rate of alfalfa hay,corn straw,corn and corn germ meal increased linearly with the increase of AOC feeding amount(P < 0.05).When fed 20 g/d and 40 g/d,DM degradation rate of alfalfa hay and corn straw was significantly higher than that of CON(P < 0.05).The DM degradation rate of corn germ meal fed 40 g/d was significantly higher than that of CON(P < 0.05);2.Rumen p H decreased first and then increased with time,and decreased to the lowest level 3～5 h after feeding.There were no significant differences in mean,maximum and minimum rumen p H,duration of p H < 5.80 and p H < 5.60 and their corresponding curve areas among the groups after feeding AOC(P > 0.05);3.The content of TVFA and the molar ratio of butyric were significantly higher in 20 g/d and 40 g/d AOC groups than in other groups(P < 0.05);AOC had no significant effect on the molar ratio of acetic,propionic and isobutyric(P > 0.05);When fed 40 g/d,the molar ratio of isovaleric and the ratio of ethylene to propylene were significantly lower than those in CON and 10 g/d groups(P < 0.05);There was no interaction between different feeding amount of AOC and VFA content at each time point before and after feeding(P > 0.05);4.AOC had no significant effect on blood cell composition of Hu sheep(P >0.05),and all indexes were within the normal physiological range of sheep;5.Compared with CON,the effect of 40 g/d AOC on rumen microorganism of Hu sheep was better α OTU,ACE,Chao 1,Shannon and Simpson indices in diversity index had no effect(P > 0.05).There was no significant effect on the microbial abundance at phylum and genus levels(P > 0.05).In conclusion,the degradation rate of AOC in rumen gradually increased with the degradation time.The ADG,DM intake and total energy intake of fattening Hu sheep were increased linearly with the increase of AOC feed;The apparent digestibility of DM,OM,CP,NDF and ADF was not significantly affected by AOC.The degradation rate of DM in the rumen of alfalfa hay and corn straw was significantly increased when 20 g/d and 40 g/d were fed;The feed quantity of AOC had no significant effect on rumen p H of Hu sheep;The results showed that TVFA content and molar ratio of butyric were increased,and the ratio of ethylene to propylene was decreased,and the rumen fermentation mode was improved;The AOC feeding amount had no significant effect on the composition of sheep blood cells in fattening lake;Rumen microorganisms compared to CON α there was no significant effect on diversity and abundance of microorganisms at the level of door and genus.