Effect of concurrent infection with Ostertagia circumcincta and Trichostrongylus vitrinus on the performance of lambs.
The interaction between Ostertagia circumcincta and Trichostrongylus vitrinus was investigated in lambs continuously infected over 12 weeks. Four groups of seven lambs were given either zero, 1000 T vitrinus larvae per day, 2500 O circumcincta larvae per day or infected concurrently. Overall liveweight gain was reduced by 17, 20 and 30 per cent in T vitrinus, O circumcincta and concurrent infection, respectively. T vitrinus infection significantly lowered serum phosphorus concentrations by week 4. In the concurrent infection the decline in phosphorus concentration was more gradual and only differed significantly from the controls during the final four weeks of the trial. There were no significant differences between the total numbers of T vitrinus or O circumcincta recovered from single or combined infections. The lack of an additive effect on performance may be due to a delayed establishment of T vitrinus in the presence of O circumcincta.
R L
RL
Coop
A C
AC
Field
R B
RB
Graham
K W
KW
Angus
F
F
Jackson
D000818:Animals; D001835:Body Weight; D004435:Eating; D005243:Feces / Q000469:parasitology; D005260:Female; D007411:Intestinal Diseases, Parasitic / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D008297:Male; D009919:Orchiectomy; D010029:Ostertagiasis / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D010270:Parasite Egg Count / Q000662:veterinary; D010435:Pepsinogens / Q000097:blood; D010758:Phosphorus / Q000097:blood; D012756:Sheep; D012757:Sheep Diseases / Q000097:blood / Q000469:parasitology* / Q000473:pathology; D014252:Trichostrongyloidiasis / Q000662:veterinary*; D014253:Trichostrongylosis / Q000097:blood / Q000473:pathology / Q000662:veterinary*
D010435:Pepsinogens; D010758:Phosphorus