Purpose: To isolate amylase producing, endospore-forming bacteria from poultry and determine the degree of relatedness between isolates.
Methods: Bacteriological media was inoculated with cecal and crop contents from broiler carcasses and incubated at 35°C for 48 h. The incubated media was heated at 80°C for 10 min, plated on Bacillus Agar, and incubated at 30°C for 24 h. Amylase production was determined by growing the bacteria on starch agar, flooding the agar with iodine, and observing for clear zones around bacterial growth. Amylase-producing bacteria were identified using the Biolog Bacterial Identification System, and endospore production was confirmed by phase microscopy. The cellular fatty acid profile of the isolates was determined using the MIDI Sherlock Microbial ID System. The dendrogram program of the Sherlock System was used to determine the degree of relatedness between the isolates.
Results: The isolates were identified as Bacillus mycoides, Bacillus pseudomycoides, Bacillus thuringiensis, Bacillus pumilus, Bacillus niabensis, Paenibacillus provencensis, Paenibacillus borealis, and Paenibacillus tarimensis by the Biolog System. Dendrograms produced by the Sherlock System grouped these isolates into three species based on Euclidean Distances of 10 or less: 1) B. mycoides, B. pseudomycoides, and B. thuringiensis grouped as Bacillus cereus; 2) P. provencensis, P. borealis, P. tarimensis, and B. niabensis were grouped as a species not in Sherlock’s library; and 3) B. pumilus alone.
Significance: The degree of relatedness of the isolates provides information that can be used to characterize bacteria that may play a role in CE. These findings will be useful in selecting isolates for inclusion in defined probiotic cultures used to reduce colonization of poultry by Salmonella.