AAAP: Litter condition affects coccidiosis
Maintaining dry litter conditions reduces coccidiosis outbreaks
3 December 2025
1 minute read
By: [Excerpts of a presentation at the 2025 annual meeting of the American Association of Avian Pathologists]
Mark Jenkins, USDA, Agricultural Research Service and Jon Schaefer, Zoetis, USA, compared sporulation and resilience of Eimeria acervulina, Eimeria maxima, and Eimeria tenella oocysts in dry and wet broiler house litter. Fecal material from chickens excreting unsporulated E. acervulina, E. maxima, or E. tenella oocysts were mixed in triplicate with dry or “wet” litter and incubated at recommended broiler house temperatures for each week of a typical growout period (8 weeks).
The Eimeria oocysts-spiked litter were incubated in an enclosed container with water added to achieve constant moisture content throughout the entire incubation period. Weekly samples were processed by floating in 1M sucrose, and Eimeria oocysts were enumerated and the percentage of sporulation determined by microscopy. Control litter not spiked with Eimeria oocysts were also included in the study and sampled throughout the entire 8-week period to account for background Eimeria oocysts.
E. acervulina, E. maxima, and E. tenella oocyst concentrations did not decrease over time in wet litter, but either displayed no decrease (E. acervulina) or a drastic decrease to undetectable levels (E. maxima, E. tenella) in dry litter. Moreover, percentage sporulation of E. acervulina, E. maxima, and E. tenella oocysts was negligible at all time-points in dry litter, but increased E. acervulina, temporally increased E. tenella, or was negligible E. maxima in wet litter. These data provide further support for maintaining dry litter conditions to reduce coccidiosis outbreaks in broiler houses.
