|Oladeinde, Adelumola - Ade|
|Weinroth, Margaret - Maggie|
|Glenn, Anthony - Tony|
Submitted to: International Poultry Scientific Forum
Publication Type: Abstract Only
Publication Acceptance Date: 12/7/2021
Publication Date: N/A
Technical Abstract: Acid amendments are used for treating re-used poultry litter between broiler chicken flocks for in-house ammonia abatement. These amendments reduce litter pH and inhibit NH3 volatilization by converting NH3 into nonvolatile NH4+, however their effect on bacterial abundance and the prevalence of pathogens is not fully understood. In this study, we investigated the diversity and changes in abundances of several bacterial foodborne pathogens (Salmonella, Campylobacter), commensal bacteria (Staphylococcus, E. coli, Enterococcus) and fungi in re-used litter from a commercial poultry house during grow-out, downtime (period after a flock was removed and before new broiler chicks were placed) and after liquid aluminum sulfate application. Our findings from three flocks show a reduction in Salmonella prevalence and Staphylococcus, E. coli and Enterococcus population abundance during downtime and after aluminum sulfate application. However, these bacterial populations either returned to pre-downtime/acidification levels or exceeded them towards the end of the grow-out period. Campylobacter was detected in all litter samples (n = 16) at the end of the 1st flock but was not detected in litter samples collected from successive flocks (n = 48). Likewise, there was a reduction in litter pH and moisture during downtime (pH = 7.14 ±0.016, moisture = 23.3 ± 0.013 % ) and after aluminum sulphate application (pH = 4.90 ± 0.15, moisture =19.5 ± 0.0021%), but these litter physio-chemical parameters increased ~ two weeks after chick placement (pH = 6.59 ± 0.030; moisture = 25.9 ± 0.013%) and by the end of the grow-out (6.82 ± 0.042; moisture = 44.3 ± 0.016%). These results suggest that downtime and litter acidification have a different effect on Salmonella persistence in pre-harvest compared to Campylobacter, and further studies are needed to disentangle this relationship.