Date of Graduation
12-2015
Document Type
Thesis
Degree Name
Master of Science in Animal Science (MS)
Degree Level
Graduate
Department
Animal Science
Advisor/Mentor
Yazwinski, Thomas A.
Committee Member
Looper, Michael L.
Second Committee Member
Powell, Jeremy G.
Third Committee Member
Rosenkrans, Charles F. Jr.
Fourth Committee Member
Fiddler, Andrew
Keywords
Biological sciences; Cattle; Co-species grazing; Haemonchus; Nematodes; Parasitology; Sheep
Abstract
The existence of anthelmintic resistance is not singular in parasite species, host species or geographic region. It has become a problem of worldly stature, especially when considering sheep nematodes. Recommendations have been modified from chemical-based control to multipart, managerial intervention. Compared with nematodes of cattle, the worldwide resistance of sheep nematodes to anthelmintic remedies is much more pronounced and urgent. As the resistance to essentially all anthelmintic classes approaches a cautionary level, the implementation of non-chemical controls has grown increasingly essential. Six-6 to 8 month old Holstein steer calves, six-5 month old Katahdin ram lambs and eight-5 month old Suffolk X Rambouillet lambs were dewormed and inoculated with either cattle-source infective nematode larvae or sheep-source infective nematode larvae. Fecal egg counts (FEC) were followed until necropsy at 39 and 40 days post inoculation. The total mean FEC were highest amongst the hair and wool sheep groups, respectively, which were inoculated with both sheep-source and cattle-source nematodes. The low fecal egg output by treatment group 1 shows that using cattle as models for the sheep-source nematodes can keep the fecundity of the nematodes low; however, caution should be taken before implementation. The host specificity of Haemonchus spp. seems to be a minimal factor in nematode fecundity.
Citation
Wray, E. M. (2015). Investigations Into the Cross-Infectivity of Nematode Parasites of Cattle and Sheep. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/1435