Controlled field trial on the anthelmintic effectiveness of the morantel sustained-release bolus in grazing calves
Presson, B.L.; Yazwinski, T.A.; Greenway, T.; Pote, L.; Newby, T.
American Journal of Veterinary Research 45(12): 2628-2630
1984
ISSN/ISBN: 0002-9645 PMID: 6395740 Document Number: 223948
In a 154-day controlled field trial, using a permanent calf pasture (divided into 2 lots), naturally parasitized calves were given the bolus when placed on the pasture. Treated calves had reduced numbers of faecal nematode eggs at every sampling period, compared with control calves. Tracer calves, added later to the treated calves, had 83-94% fewer nematodes than their counterparts with the controls. Plasma pepsinogen values were higher in the controls from day 54 onwards. At trial termination, treated calves weighed 27.8 kg more and had 80.9% fewer nematodes than controls.