|RICHARDSON, KURT - Anitox Corp|
|Cox, Nelson - Nac|
|POWELL, ANDRA - Anitox Corp|
|WELLER, CHERYL - Anitox Corp|
Submitted to: Journal of Environmental Science and Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/8/2020
Publication Date: N/A
Interpretive Summary: One source of Campylobacter in broilers that has been overlooked is the feed and primarily because conventional methods have been unable to detect this organism in feed. The cause of this is the inability to suppress certain extraneous microorganisms during enrichment and the subsequent drop in pH leading to hostile acidity in the enrichment media. This study is the first step in determining the most appropriate combination of antibiotic supplements to inhibit extraneous flora and subsequent decrease in pH during enrichment allowing Campylobacter to be isolated from feed two weeks after inoculation.
Technical Abstract: Studies were conducted to investigate the enrichment recovery of Campylobacter from feed under a variety of conditions. Five experiments were conducted, each one to test a different feed characteristic: 1. initial feed moisture, 2. feed water activity, 3. initial number of aerobic bacteria in the feed, 4. numbers of aerobic and anaerobic microflora within the enrichment samples post-incubation, and 5. pH of enrichment medium pre- and post-incubation. In each experiment, samples were enriched for Campylobacter in Campylobacter enrichment broth (CEB) containing different antibiotic supplements. Broiler starter feed was inoculated was at a rate of 104-105 cfu/g and stored at 24°C and 43% RH. Enrichment culture was conducted on the day of inoculation or 24 h post inoculation and every 48 h of storage thereafter for 14 d. Initial feed moisture, water activity, and numbers of bacteria in feed were not correlated with recovery of Campylobacter. Addition of antimicrobial supplements to CEB resulted in maintenance of a near neutral pH. Campylobacter was recovered up to 10 days post inoculation when using CEB containing supplements compared to 1 day in CEB. These findings suggest that antimicrobial supplementation can improve Campylobacter recovery from feed by controlling extraneous microbial growth during enrichment.