[Some epidemiological features of salmonellosis in veal calves in the Netherlands (author's transl)].
In the Netherlands, salmonellosis in veal calves is caused by S. dublin and S. typhimurium. Strains showing multiple drug resistance are important factors in these cases. Strains of S. typhimurium isolated from dead veal-calves resistance are important factors in these cases. Strains of S. typhimurium isolated from dead veal-calves are confined to a small number of phage types (mainly X 200, X 210, X 193, X ORS). To trace the Salmonella organisms to their origin, faecal samples were collected from one week old calves in markets, in lorries and within 24 hours after their arrival on veal-calf units, and subsequently examined for the presence of Salmonella. Salmonella (47.5 per cent of S. typhimurium, 20 per cent of S. dublin and 32.5 per cent of other serotypes) was isolated from 3.5 per cent of the individual faecal samples of 1,143 calves on seven veal-calf farms (1976-1978). Clinical symptoms caused by S. typhimurium and the other serotypes were not observed on these farms, whereas there were individual cases due to S. dublin. The phage types of S. typhimurium isolated (I 650, VI 260 and II 505) obviously had little if any pathogenic significance in calves. During the period from October 1977 to November 1978. Salmonella was isolated from nearly 6 per cent of 1,880 calves in the markets (S. typhimurium 50 per cent, S. dublin 17 per cent and other serotypes 33 per cent). Well over 25 per cent of the strains of S. typhimurium isolated were of the pathogenic phage types (X 201, X ORS). Salmonella was isolated from well over 30 per cent of eighty-three lorries. It is concluded that markets and lorries are important factors in the epidemiology of salmonellosis in veal calves. However, there also are persistent infections in veal-calf units. Possible routes of infection, in which the veal calf is regarded as the most important source of infection, are discussed. More detailed epidemiological studies are in progress to make it possible to suggest measures by which the incidence of salmonellosis in the Netherlands may be reduced.
D000818:Animals; D001431:Bacteriological Techniques; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology; D005243:Feces; D009426:Netherlands; D012475:Salmonella / Q000302:isolation & purification; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D012483:Salmonella Phages / Q000472:pathogenicity
Enkele epidemiologische aspecten van salmonellose bij mestkalveren in Nederland.