Infection with Cochlosoma anatis in early brooding leads to poor health outcomes in turkey poults

Infection with Cochlosoma anatis , a flagellated protozoan parasite, significantly impacts U.S. commercial turkey production by causing poult enteritis (poor weight gain, flock non-uniformity, and diarrhea) and is associated with co-infections. Though unconfirmed, prior research suggests impaired nutrient acquisition or utilization. This study investigated how infection timing affects disease severity in turkey poults, hypothesizing that inoculation at early brooding (placement or 8 days of age) would lead to more severe outcomes relative to inoculation at 15 days of age or non-infected controls (NC). Poults were orally inoculated with a C. anatis field strain and performance recorded for 28 days. Ileal C. anatis concentrations and cecal tonsil concentrations of Escherichia coli , total coliforms, Clostridium perfringens , and Salmonella were measured at 28 days of age. Mortality was normalized with the Freeman-Tukey double arcsine transformation, and all parameters were assessed using a one-way ANOVA and Tukey-Kramer mean separation in JMP Pro 16. Mortality was significantly higher (p=0.0007) with inoculation at placement and 8 days of age (up to 70%) compared to those inoculated at 15 days of age (16%) and the NC group (8%). Initial weights were similar; however, poults inoculated at placement had significantly lower (p<0.0001) final body weights (408.42 g/poult) compared to inoculation at 8 and 15 days of age (∼587 g/poult) and the NC group (797.51 g/poult). C. anatis and bacterial concentrations did not significantly differ. This study showed that C. anatis infection in early brooding leads to severe disease, highlighting the fragility of young poults susceptible to C. anatis infection.