In-house litter composting has been shown to reduce bacteria in broiler litter, according to a recent USDA study. However, reduction in natural flora of waste residual may lead to increased re-colonization of other bacteria pathogens due to reduced competition. Laboratory studies were conducted to: 1) determine re-colonization of food-borne bacterial pathogens (by inoculation with Salmonella, Campylobacter, Clostridium and Listeria) in composted and non-composted litter; 2) identify bacteria associated with reduced pathogen re-colonization; and 3) correlate ammonia levels on pathogen re-colonization.
Food-borne bacteria were higher in composted litter in weeks 1 and 2. However, bacterial levels were identical in both litter treatments by week 7. Upon ceasing addition of inoculated fecal matter, food-borne bacterial pathogens were overtaken by normal litter bacteria in both treatments. No differences could be attributed to ammonia levels.
In summary, while initial (week 1 and 2) microbial levels were reduced and food-borne pathogens were increased in composted litter, bacterial levels were similar in composted and non-composted litter treatments by week 7.
Project #662: Bacterial Re-colonization of In-House Composted Broiler Litter (John P. Brook, Ph.D., USDA ARS, Genetics and Precision Agriculture Unit, Mississippi State, MS).
A complete report, along with information on other Association research, may be obtained by going to USPOULTRY's website.
