Isolation of Salmonella serotypes from feces of pigs raised in a multiple-site production system.
OBJECTIVE
To determine the prevalence and serotypes of Salmonella organisms in feces of pigs raised in a modern, multiple-site production system.


METHODS
Cross-sectional study of prevalence.


METHODS
Swine housed on 7 farms (1 gilt development farm, 2 breeding farms, 1 nursery farm, and 3 finishing farms) that formed a multiplesite production system.


METHODS
Fecal samples were obtained from 792 pigs (96 to 202/farm) and submitted for bacteriolgic culture of Salmonella organisms.


RESULTS
Salmonellae were isolated from pigs on all 7 farms and from 95 of 792 (12%) fecal samples. Prevalence ranged from 3.4% at the gilt development farm to 18 and 22% at the breeding farms. Serotypes identified were Salmonella derby, S typhimurium var. copenhagen, S heidelberg, S typhimurium, S mbandaka, S worthington, and S tennessee. No single serotype was not isolated from all the farms of the production system and the most prevalent serotypes at the 3 finishing farms (S typhimurium or S typhimurium var. copenhagen) were not isolated from the breeding or nursery farms.


CONCLUSIONS
Upstream infection (pigs infected before arriving at finishing farms) appears to be an unimportant source of Salmonella infection of finished hogs in multiple-site systems. High prevalence of Salmonella shedding in breeding animals suggests that food products derived from culled breeding livestock may be an important source of foodborne disease.
Davies
P R
PR
Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
Bovee
F G
FG
Funk
J A
JA
Morrow
W E
WE
Jones
F T
FT
Deen
J
J
D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D003430:Cross-Sectional Studies; D005243:Feces / Q000382:microbiology*; D005260:Female; D008297:Male; D009657:North Carolina / Q000453:epidemiology; D015995:Prevalence; D012475:Salmonella / Q000145:classification* / Q000302:isolation & purification; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D012703:Serotyping / Q000662:veterinary; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000382:microbiology