Tissue response of goats to single or repeated low-level doses and to a massive challenge dose of Schistosoma bovis.
The inflammatory tissue response to Schistosoma bovis in the small intestine and liver of goats was studied by light microscopy 32 weeks after they had been exposed to 10 weekly ('trickle') doses of 200 cercariae or to a single dose of 400 cercariae, and 32 weeks after the same dosing schedules followed by a challenge exposure to 2000 cercariae in week 16 of the experiment, and 16 weeks after a single exposure to 2000 cercariae in week 16 (challenge control). The tissue egg counts in the small intestine were highest in the challenge control group and comparable in the other groups, and corresponded well with the numbers of inflammatory foci per histological section of gut wall. The tissue egg counts in the liver were also highest in the challenge control group, but diffuse hepatic portal fibrosis was more pronounced in the groups with a primary exposure followed by a challenge. The intestinal pathology was compatible with a smaller component of vigorous and acute inflammatory reactions to the eggs in the older than in the more recent infections. The magnitude and morphological characteristics of the inflammatory tissue response did not differ markedly between the goats exposed to the trickle infections and the single doses, and they were not substantially affected by the challenge infection.
Lindberg
R
R
Department of Pathology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala.
Monrad
J
J
Johansen
M V
MV
Christensen
N O
NO
Nansen
P
P
D000704:Analysis of Variance; D000818:Animals; D015511:Goat Diseases / Q000473:pathology*; D006041:Goats; D007249:Inflammation / Q000469:parasitology / Q000662:veterinary; D007422:Intestines / Q000469:parasitology / Q000473:pathology; D008099:Liver / Q000469:parasitology / Q000473:pathology; D008297:Male; D012552:Schistosomiasis / Q000473:pathology / Q000662:veterinary*