Isolation and characterization of actinomycetes from healthy goat faeces.
ABSTRACT To isolate and characterize actinomycetes with probiotic activities from healthy goat faeces.
Faecal actinomycetes were isolated by dilution methods and identified by 16S rRNA gene sequence analysis. The hydrolytic enzyme activities were analysed by clear zone formation. The antimicrobial activities and resistance to heavy metals were tested by growth inhibition methods. The isolates belong to a small group of actinobacterial genera, including Streptomyces, Nocardiopsis and Oerskovia. The Oerskovia was the most widely distributed genus among the cultures. The proportion of streptomycete-like strains producing amylase or protease is significantly higher than those of other actinomycetes (P < 0.05). Compared with streptomycete-like strains, a higher proportion of (alpha- or beta-) galactase-producing other actinomycetes was found in goat faeces. More than 50% of streptomycete-like strains showed activities against test fungi. Streptomycetes could tolerate 0.25 mmol l(-1) Cr(2)O(7)(2-), 2 mmol l(-1) Ni(2+); however, other actinomycetes are liable to 40 mmol l(-1) Fe(3+) and 0.25 mmol l(-1) Cr(2)O(7)(2-) and resistant to 5 mmol l(-1) Ni(2+) and 2 mmol l(-1) Cu(2+).
The different physiological characteristics of the actinomycetes suggested that the cooperation in the actinomycetes might be involved in their association with goat.
Probiotic mixtures based on faecal actinomycetes showed potentials in animal production.
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ABSTRACT: Gut microbiota has become an integral component of the host, and received increasing attention. However, for many domestic animals, information on the microbiota is insufficient and more effort should be exerted to manage the gastrointestinal bacterial community. Understanding the factors that influence the composition of microbial community in the host alimentary canal is essential to manage or improve the microbial community composition. In the present study, 16S rRNA gene sequence-based comparisons of the bacterial communities in the grass carp (Ctenopharyngodon idellus) intestinal contents and fish culture-associated environments are performed. The results show that the fish intestinal microbiota harbors many cellulose-decomposing bacteria, including sequences related to Anoxybacillus, Leuconostoc, Clostridium, Actinomyces, and Citrobacter. The most abundant bacterial operational taxonomic units (OTUs) in the grass carp intestinal content are those related to feed digestion. In addition, the potential pathogens and probiotics are important members of the intestinal microbiota. Further analyses show that grass carp intestine holds a core microbiota composed of Proteobacteria, Firmicutes, and Actinobacteria. The comparison analyses reveal that the bacterial community in the intestinal contents is most similar to those from the culture water and sediment. However, feed also plays significant influence on the composition of gut microbiota.PLoS ONE 01/2012; 7(2):e30440. · 4.09 Impact Factor