Excretion in feces and mucosal persistence of Salmonella ser. Typhimurium in pigs subclinically infected with Oesophagostomum spp.
OBJECTIVE
To determine interactions between Oesophagostomum spp and Salmonella ser. Typhimurium in pigs.


METHODS
30 healthy 5- to 6-week-old pigs.


METHODS
Pigs were allotted to 3 groups (n = 10 pigs/group) and treated as follows: group A was given Oesophagostomum dentatum and O quadrispinulatum; group B was given O dentatum, O quadrispinulatum, and S Typhimurium; and group C was given S Typhimurium only. Pigs in groups A and B were trickle infected with Oesophagostomum spp 3 times weekly throughout the study. After 19 days, groups B and C were inoculated once with S Typhimurium. One pig from each group was euthanatized on the day of Salmonella exposure and 2 and 4 days after Salmonella exposure. The remaining pigs were euthanatized on days 16 and 17 after Salmonella exposure.


RESULTS
Pigs with dual infections of nematodes and bacteria (group B) excreted significantly higher amounts of S Typhimurium in feces, compared with nematode-free pigs (group C). In addition, group-B pigs excreted S Typhimurium on more days than pigs in group C. Salmonella Typhimurium was detected in the cecum and colon in the majority of pigs in group B, whereas S Typhimurium was only detected in the colon in pigs in group C. Immunohistochemical examination detected S Typhimurium in 7 of 9 pigs in group B but only 2 of 9 pigs in group C.


CONCLUSIONS
Interactions between intestinal nematodes and bacteria may play an important role in the dynamics of S Typhimurium infections.
Steenhard
Nina R
NR
Danish Centre for Experimental Parasitology, The Royal Veterinary and Agricultural University, Dyrlaegevej 100, DK-1870 Frederiksberg C, Copenhagen, Denmark.
Jensen
Tim K
TK
Baggesen
Dorte L
DL
Roepstorff
Allan
A
Møller
Kristian
K
D000818:Animals; D002432:Cecum / Q000382:microbiology; D003106:Colon / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D005260:Female; D007413:Intestinal Mucosa / Q000382:microbiology*; D008297:Male; D009814:Oesophagostomiasis / Q000382:microbiology / Q000503:physiopathology / Q000662:veterinary*; D012481:Salmonella Infections, Animal / Q000469:parasitology / Q000503:physiopathology*; D012486:Salmonella typhimurium / Q000502:physiology*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology* / Q000469:parasitology*