Prevention of pathophysiologic and immunomodulatory effects of gastrointestinal nematodiasis in calves by use of strategic anthelmintic treatments.
Effects of strategic anthelmintic treatment on pathophysiologic and immunomologic changes induced by infection with Ostertagia ostertagi and Cooperia oncophora were studied in 2 groups, of 12 calves each: an infected group, inoculated with 200,000 mixed O ostertagi and C oncophora third-stage larvae (L3) on day 1; and an infected-treated group, similarly inoculated, but treated with ivermectin at 9 and 33 days. All calves were also inoculated at 12 weeks with Brucella abortus vaccine, at 13 weeks with bovine rhinotracheitis vaccine (bovine herpesvirus 1), and at 14 weeks with a soluble O ostertagi L3 extract, then were allowed to graze on a contaminated pasture. Four calves from each group were slaughtered at 7, 11, and 19 weeks of the study. Calves of the infected group had significantly (P < 0.05) lower weight gain than did those in the infected-treated group (60.90 kg vs 75.86 kg). They also had high plasma pepsinogen and serum gastrin values, and low serum albumin concentration from 2 or 4 weeks. Calves in the infected-treated group had steady weight gain and no significant changes in albumin and gastrin values. They also had less severe abomasal lesions and higher carcass yield. Compared with calves of the infected-treated group, those of the infected group had significantly (P < 0.05) lower blood lymphocyte reactivity to phytohemagglutinin at 14 and 16 weeks, to concanavalin A at 10 weeks, to pokeweed mitogen at 14 weeks, and to soluble O ostertagi L3 extract at 2, 4, and 14 weeks. (ABSTRACT TRUNCATED AT 250 WORDS)
Yang
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C
Department of Animal, Veterinary and Aquatic Sciences, University of Maine, Orono 04469.
Gibbs
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HC
Xiao
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Wallace
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CR
D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D001835:Body Weight; D002004:Brucella Vaccine / Q000008:administration & dosage*; D002003:Brucella abortus / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases; D005755:Gastrins / Q000097:blood; D005767:Gastrointestinal Diseases / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D009348:Nematoda / Q000302:isolation & purification; D009349:Nematode Infections / Q000503:physiopathology / Q000517:prevention & control / Q000662:veterinary*; D009919:Orchiectomy; D010029:Ostertagiasis / Q000503:physiopathology / Q000517:prevention & control / Q000662:veterinary*; D010270:Parasite Egg Count; D010435:Pepsinogens / Q000097:blood; D013997:Time Factors; D014765:Viral Vaccines / Q000008:administration & dosage*; D015430:Weight Gain
D000871:Anthelmintics; D002004:Brucella Vaccine; D005755:Gastrins; D010435:Pepsinogens; D014765:Viral Vaccines