Epidemiology of Salmonella infections in sow herds in the Czech Republic

Salmonella prevalence was assessed in six herds of sows by serological ELISA test and faecal culture. Blood and faecal samples were collected, prior to weaning of piglets, from 45 sows housed in separated pens in each group of a herd. Increased levels of specific antibodies were found in all six herds. Serologically positive samples averaged 41 .85%. Faecal shedding of Salmonella from the carriers was found in four herds with the average of 7.8%. Salmonella prevalence, as assessed by serological testing and faecal culture, was 17.8% and 13.3% in herd I, 20.0% and 4.4% in herd II, 40.0% and 20.0% in herd Ill , 53.3% and 0% in herd IV, 86.7% and 8.9% in herd V, and 30.3% and 0% in herd VI. A total of 21 Salmonella spp. strains were isolated which were classified into the serotype Derby (n=17), London (n=2). Bredeney (n=1 ), and Gold coast (n=1 ). All isolates were sensitive to the antibiotics used. No correlation was found between Salmonella seroprevalence in ELISA test and positive faecal culture in the examined herds of sows. The result of faecal culture was negative in two sow herds with high seroprevalence. Serological ELISA test is an efficient diagnostic tool for Salmonella detection in suspected herds. The results of our study showed association between the incidence of S. Derby in sows and slaughtered fattening pigs originated from the same farrow-to-finish herds.