The prevalence of salmonellae in poultry, cattle, pigs and animal feeds in Jamaica

ABSTRACT

The prevalence of Salmonella in certain food animals - poultry, cattle and pigs - and their food stuffs, was investigated in Jamaica for the first time. A total of 1,076 samples were examined. Samples of faeces and cloacal swabs were taken from poultry at the time of slaughter, at a processing plant in Jamaica in 1968. This was repeated in 1971 when poultry from three other plants were also tested. 28 of 323 (8.7 percent) samples yielded Salmonella. The recovery rate for the factories varied between 0 percent and 15 percent. The patterns of recovery indicated that good sanitation and equipment lowered the incidence of salmonellae in poultry. Serotypes isolated were S. blockely (8 isolates), S. typhimurium var copenhagen and S. albany (6 isolates each), S.bredeney (5 isolates), S. saint paul, S. infantis and S. haadt (one isolate each). Improved methods of sanitation appear to be needed, especially for handling giblets. A survey of pigs and cattle at the Kingston abattoir was made in 1968 and repeated in 1972. At the first survey 52 samples were taken from cattle and consisted of swabs of liver, spleen and mesenteric lymph nodes. 25 samples were taken from pigs, consisting of swabs of liver and spleen. No salmonellae were recovered. During the second survey in 1972, a total of 101 samples were taken from pigs, cattle, the environment (cutting surfaces, knives, floors, etc.) and from the abattoir effluent. Thirty six percent of these were found to be positive for Salmonella. Mesenteric nodes (comminuted) and faecal swabs together yielded 3 Salmonella isolates from 24 samples of cattle (12.5 percent) and 24 Salmonella isolates were made from 41 samples of pigs (54 percent). The differences in recovery of salmonellae between the two surveys was considered to be due to differences in sampling method and site. The efficiency of recovery of Salmonella from these two sources was compared. Brilliant Green (BG) and xylose-lysine-deoxycholate (XLD) agars, were compared for relative rates of recovery of salmonellae. The serotypes isolated from cattle were S. ohio (2 isolates) and S. meleagridis (one isolate). Ten of the 22 isolates cultured from pigs were serotyped with the following results: S. anatum (3 isolates), S. senftenberg (2 isolates), S. derby (2 isolates), S. heidelberg (one isolate), S.bonariensis and S. meleagridis (one isolate each). One hundred and thirteen samples of animal feeds and feed ingredients were analysed for Salmonella in 1968. Seven (6 percent) of these were found to be positive by the conventional cultural (CC) method. Fifty eight of these were also examined by the fluorescent antibody (FA) method of Ellis, and 9 were found positive for Salmonella. However, only 4 of these were confirmed by the CC method. Three that yielded Salmonella by the CC method were negative by FA. Serotypes isolated were S. eimsbuettel (4 isolates), S. senftenberg (2 isolates) and S. albany (one isolate). Human serotypes isolated at the University Hospital and by the Government Bacteriological Laboratory were examined in order to note if any relationship could be detected between predominant serotypes isolated from humans and those isolated from animals and their feeds. The 10 Salmonella serotypes most frequently isolated from humans in Jamaica between 1967 and 1971 in order of frequency were S. derby, S. typhimurium, S. infantis, S. oranienburg, S. enteritidis, S. saint paul, S. panama, S. san diego, S. heidelberg and S. anatum. There was no clear evidence of direct relationship between serotypes isolated from humans and those from food animals and their feeds. Four hundred and eighty seven food samples were examined, but none yielded Salmonella. These included poultry and pig products (sausages). The need for detailed attention towards bacteriological standards and all other aspects of the sanitary control of poultry processing plants and abattoirs was indicated (AU)