Effects of Low Levels of Lice and Internal Nematodes on Weight Gain and Blood Parameters in Calves in Central Texas
Autor: | Thomas M. Craig, Loyd D. Rowe, Catherine Wade, Daniel K. Miller, Joyce A. DeVaney |
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Rok vydání: | 1992 |
Předmět: |
Male
Population Cattle Diseases Louse Weight Gain medicine.disease_cause Animal science biology.animal Infestation medicine Animals Helminths Trichostrongylus Intestinal Diseases Parasitic Nematode Infections education Eggs per gram education.field_of_study Ecology biology Ostertagia General Medicine Lice Infestations Bovicola bovis biology.organism_classification Insect Science Immunology Cattle |
Zdroj: | Journal of Economic Entomology. 85:144-149 |
ISSN: | 1938-291X 0022-0493 |
DOI: | 10.1093/jee/85.1.144 |
Popis: | The effects of low levels of both biting and sucking lice, a mixed population of nematodes, and a combination of all these parasites were evaluated in calves held in a barn with no environmental controls in central Texas. Observations at 122 sites on each animal for 16 wk consecutively in 1987 revealed that the largest numbers of all louse species [Haematopinus eurysternus (Nitzsch). Linognathus vituli (L.), and Bovicola bovis (L.)] occurred 3-7 wk after infestation. In 1988 L. vituli populations decreased rapidly after the 3rd wk and B. bovis remained fairly constant for 20 wk consecutively. Average nematode egg counts increased to approximately 300 eggs per gram of feces in 1987 and approximately 600 eggs per gram of feces in 1988. The nematodes Ostertagia ostertagia, Haemonchus placei, Oesophagostomum radiatum, Cooperia spp., and Trichostrongylus spp. were present at the end of the study in both years as determined by necropsy. No significant differences in erythrocyte count, mean cell volume, hematocrit, hemoglobin concentration, leukocyte counts, or serum albumin concentration were detected. However, significant increases in total serum protein concentration and serum globulin levels in calves harboring both groups of parasites were observed. Mean weight gain in calves infested with lice and nematodes was 11.4 and 10 kg less than that of uninfested controls during 16 wk in 1987 and 20 wk in 1988, respectively. |
Databáze: | OpenAIRE |
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