Effects Of Probiotics E.Faecium HDRsEf1on The Development Of Cecal Bacterial Flora In Broilers

This trail added Enterococcus faecium HDRsEf1, which were screened in our lab and had probiotic properties, to the corn-soybean ration. DGGE was used to estimated the changes of cecal bacterial flora. RT-PCR was used to quantify the number of specific microflora in cecal. Besides, molecular biological technique was used to monitor concrete changes of cecal bacterial flora in broilers from the age of7to14.Finally, to study the effect of broilers resisting E.coli078, which was feeding of Enterococcus faecium HDRsEf1, the bacterium capacity in tissue and lesion of tissue was detected. The results and conclusions display as following.1Effects of E.faecium HDRsEf1on the development of cecal bacterial flora in broilersOne hundred and eighty newborn broilers were divided randomly into the control(basal diet), the probiotics(basal diet+300g/t Enterococcus faecium) and the antibiotics(basal diet+50mg/kg Aureomycin). Each treatment had3replicates of20birds. The digesta in cecal were sampled sterilely and rapidly from the broilers at the age of7,14,21,28,35and42respectively. RT-PCR was used to quantify the number of Escherichia coli and Lactobacilli. DGGE was used to estimated the changes of cecal bacterial flora. The results showed that adding of probiotics could reduce the numbers of Escherichia coli at the age of21and increase the numbers of Lactobacilli at the age of42significantly(P<0.05). The DGGE profiles showed cecal bacterial flora of broilers from7d to14d was a transitional period, and cecal bacterial flora from14d to42d was a relatively stable period. Adding of probiotics and antibiotics would not have any effect on normal development of cecal bacterial flora. However, contrary to the antibiotics, the cecal bacterial flora in probiotics could get through transition more efficiently in the transitional period and keep more steadily in the relatively stable period.2Dynamic transformation rules of cecal bacterial flora in little broilersSixty newborn broilers were divided randomly into there repetitive groups, each group had20birds. The birds were feed of basal diet, experimental period was14days. The digesta in cecal were sampled sterilely and rapidly from the broilers at the age of7,9,10,11,13and14respectively. DGGE was used to estimated the changes of cecal bacterial flora. The results of UPGMA showed that the age of10was a critical point of cecal bacterial flora in little broilers. Cecal bacterial flora was in solution from7d to9d and began to stabilize after10d. DGGE profiles showed that there were five common bands during this transfer. The corresponding potential bacterium species were Ruminococcus lactari, Azomonas agilis, Propionibacterium acnes, Streptococcus oralis and Microbacterium testaceum. After10d, some special bands appeared, The main corresponding bacterium species were Eubacterium limosum, Lactobacillus crispatus, Corynebacterium jeikeium and Brachybacterium sacelli.3Effect of inhibition of E.faecium HDRsEfl on the invasion by E.coli O78in broliersSixty newborn broilers were divided randomly into the control, the probiotics and the antibiotics. Each group had twenty birds. Taking orally1mL with2X107CFU/mL concentration E.coli O78at the age of10. The bacterium capacity in tissue and lesion of tissue was detected. Bacterium capacity in tissue and lesion of tissue were detected at72hours after infection. The results showed that adding of Efaecium and Aureomycin could reduce the numbers of E.coli present in heart and liver significantly(P<0.05). They could reduce the numbers of E.coli present in blood and ceca too, but it had not significant difference(P>0.05). The results of pathological observation showed ballooning degeneration of liver cells and hepatic steatosis appeared in all of three groups. However, the lever of epicardial hyperplasia and cardiomyocyte degeneration was harder than two other groups.