Prevalence of Campylobacter jejuni in Small-Scale Broiler Operations and the Effects of Sulfadimethoxine Administered to Control C. jejuni Infection in Broilers

Campylobacter spp. particularly C. jejuni has been recognized as one of the most prevalent causes of foodborne bacterial illnesses in humans. Most previous studies have focused on the transmission routes of C. jejuni from commercial flock farms to the final retail product. To date, no in vivo studies have addressed the efficacy of sulfadimethoxine in the control of C. jejuni in poultry. This dissertation research proceeds along two lines of investigation. The objectives of the first line of investigation are to determine the enumeration of Campylobacter spp. and the prevalence on both Campylobacter spp. and C. jejuni on live egg shells, to detect the presence and extent of Campylobacter spp. and C. jejuni in live birds raised in battery-cage and cage-free systems and to determine to what extent these bacteria are present in drinking water, feed, enclosures and troughs. The objectives of the second line of investigation are to determine the effects of sulfadimethoxine antibiotic on the enumeration of Campylobacter spp. and the prevalence on both Campylobacter spp. and C. jejuni in broilers and to examine the effects of sulfadimethoxine antibiotic treatments on the enumeration of Campylobacter spp. and prevalence of Campylobacter spp. and C. jejuni from likely sources of cross-contamination to include drinking water, feed, enclosures and troughs. The results from the first line of investigation suggest that the vertical transmission of these bacteria from egg surfaces to newly hatched chicks is not a significant risk factor. Additionally, this study found that the horizontal transmission of Campylobacter spp. and C. jejuni among live broilers is significantly higher (P<0.05) raised in the cage-free system than in the battery-cage system. Prevalence of Campylobacter spp. and C. jejuni in the potential abiotic sources of cross contamination (drinking water, feed, enclosures and troughs) in the cage-free system was significantly higher than in the battery-cage system. The results from the second line of investigation also found that drinking water may be a prime source of Campylobacter spp. and C. jejuni cross contamination. The use of antibiotic sulfadimethoxine can reduce the enumeration and prevalence of Campylobacter spp. and the prevalence of C. jejuni.