SALMONELLA ISOLATED FROM ANIMALS AND FEED STUFFS IN SWEDEN DURING 1978-1982

  • 1 January 1984
    • journal article
    • research article
    • Vol. 36  (11) , 371-393
Abstract
Regulations concerning the control of Salmonella in animals are more strict in Sweden than in most other countries, though a certain liberalization took place in 1982. The main purpose of these regulations is to prevent transmission of Salmonella infections from animals to man. Veterinarians and laboratories are obliged to report all Salmonella cases to the veterinary authorities. The cases are recorded by the Swedish Board of Agriculture. From 1978-1982, 1266 outbreaks of Salmonella in animals were recorded. Isolated strains belonged to 78 different serotypes. The most frequent serotypes were S. typhi-murium (38.5% of the recorded cases) and S. dublin (37%). S. dublin was isolated mainly from cattle, while S. typhi-murium was isolated from a wide range of animal species. Next in frequency are some serotypes isolated mainly from chicken, at rates around 2%; S. livingstone, S. liverpool and S. agona. Of the 78 isolated serotypes, 25 were never isolated before from animals in Sweden. There were 687 outbreaks of Salmonella recorded in cattle. Predominant serotypes are S. dublin (67% of the outbreaks in cattle) and S. typhi-murium (28%). The outbreaks of S. dublin, like those in the sixties and seventies, occurred mainly in southeastern Sweden. The recorded occurrence of Salmonella in swine continued to decrease. During this period only 37 outbreaks were diagnosed. Of these, more than 1/2 were caused by S. typhi-murium. S. cholerae-suis was isolated from 6 cases only. The number of outbreaks diagnosed in poultry has increased. During the period of this report, 220 outbreaks were recorded. Most of this increase occurred during 1981 and 1982. From poultry, 35 serotypes were isolated, S. typhi-murium being the most frequent (17%). Some of the outbreaks were found to be connected with the distribution of contaminated chicken-feed. From the wild fauna, 190 cases have been recorded. As in previous years, certain kinds of small birds suffer most from Salmonella. The birds are infected when gathered in large numbers at places where they are fed during winter. Most frequently they are infected with S. typhimurium phage-types 1 or 9. There is an extensive Salmonella surveillance of domestic feed products, by means of a routine bacteriological supervision of the production in the factories. At these examinations most of the Salmonella isolations have been made from meat meal and products of meat meal. In total, 524 Salmonella strains belonging to 47 different serotypes have been isolated. Even the import of animal feed is subject to Salmonella surveillance, 67 Salmonella strains belonging to 14 serotypes having been found in feedstuffs of animal origin intended for importation.