Enumeration and isolation of anaerobic microbiota of piggery wastes

Abstract

Media for enumeration of the microbiota of anaerobically stored piggery wastes were tested. Highest colony counts were obtained with 80 to 100% farm slurry supernatant included in the anaerobic roll tube media. Colony counts with these media numbered 2 X 10(9) to 12 X 10(9)/g (wet weight), which represents about 20% of the microscopic counts. Lower percentages of slurry supernatant in the media gave lower colony counts. Addition of glucose, cellobiose, and starch or of Trypticase to media with 20% slurry supernatant did not increase colony counts. Higher values were obtained when hemicellulose preparations were added to these media. Incubation at 25 degrees C gave the highest numbers. Incubation at 15 to 37 degrees C gave counts of about 70 and 10%, respectively, of those at 25 degrees C. Of the colonies picked for isolation, about 20% were obtained in pure culture. The isolates apparently belonged to the genera Peptococcus, Ruminococcus, Peptococcus, Ruminococcus, Pepostreptococcus, and Bacteroides.