ABSTRACT
In order to maintain the high production and export rates achieved by the Brazilian poultry industry, it is necessary to prevent and control certain disease agents, such as Salmonella spp. Using bacterial cultures, the aim of the present study was to investigate the prevalence of Salmonella spp. in specimens collected from broiler facilities. Local wild birds were also sampled, as well as the feces of swine housed on the poultry farm. After sample collection, the isolated serotypes were subsequently inoculated into broiler chicks to determine their effects. Positive samples were collected from the following locations in the poultry facilities: poultry litter (S. serotype 4,5,12:R:-; S. Heidelberg; S. Infantis), broiler feces (S. Heidelberg; S. serotype 6,7:R:-; S. serotype 4,5,12:R:-; S. Tennessee), water (S. Glostrup; S. serotype 6,8:d:-;), and lesser mealworms (Alphitobius diaperinus) found in the litter (S. Tennessee). Among the 36 wild birds captured, S. Heidelberg was isolated from one bird's organs and intestinal contents (Colaptes campestris), and S. Enteritidis was isolated from another bird's intestinal contents (Zenaida auriculata). Salmonella Panama and Salmonella Typhimurium were isolated from swine feces. One-day-old chicks (150) were divided into 10 groups of 15 animals each. Each group was orally inoculated with a previously isolated serotype of Salmonella. Soft stools were observed on the cage floor and around the birds' cloaca between 3 and 12 days post-infection (dpi). The different serotypes of Salmonella used to inoculate the chicks were re-isolated from the spleen, liver, and cecal content samples of the infected birds on 15 and 21 dpi.
ABSTRACT
This study was carried out to investigate the presence of Salmonella sp in flocks of white laying hens. In different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of Salmonella. Four positive (A, B, L and M) and one negative (I) flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. Birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. Salmonella enterica serovar Enteritidis and S. enterica rough strain were isolated from the transport boxes of the four positive flocks (flocks A, B, L and M). Salmonella sp was not isolated from the transport boxes or from the feces after 76 weeks-old in flock I. Salmonella sp was isolated in the 1st, 11th, 34th, 42nd and 76th weeks from flock A; in the 1st, 4th, 11th and 76th weeks from flock B; in the first week and in the 17th to 52nd weeks from flock L; and in the 1st and 76th weeks from flock M. S. Enteritidis, S. enterica rough strain and Salmonella enterica serovar Infantis were isolated from the four positive flocks. Besides, Salmonella enterica serovar Javiana was isolated from flocks B and L, and Salmonella enterica serovar Mbandaka was isolated from flock L. Eggs produced by flock A and by flock L were contaminated with S. Enteritidis and S. enterica rough strain. According to these results, Salmonella-infected flocks may produce contaminated eggs.
ABSTRACT
This study was carried out to investigate the presence of Salmonella sp in flocks of white laying hens. In different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of Salmonella. Four positive (A, B, L and M) and one negative (I) flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. Birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. Salmonella enterica serovar Enteritidis and S. enterica rough strain were isolated from the transport boxes of the four positive flocks (flocks A, B, L and M). Salmonella sp was not isolated from the transport boxes or from the feces after 76 weeks-old in flock I. Salmonella sp was isolated in the 1st, 11th, 34th, 42nd and 76th weeks from flock A; in the 1st, 4th, 11th and 76th weeks from flock B; in the first week and in the 17th to 52nd weeks from flock L; and in the 1st and 76th weeks from flock M. S. Enteritidis, S. enterica rough strain and Salmonella enterica serovar Infantis were isolated from the four positive flocks. Besides, Salmonella enterica serovar Javiana was isolated from flocks B and L, and Salmonella enterica serovar Mbandaka was isolated from flock L. Eggs produced by flock A and by flock L were contaminated with S. Enteritidis and S. enterica rough strain. According to these results, Salmonella-infected flocks may produce contaminated eggs.