Influence of nematode infections on hematological parameters of crossbred calves

The effect of nematode infections on hematological parameters was evaluated in calves over a period of 18 months in a county of the Minas Gerais State, Brazil. Fourteen crossbred calves (ages between three and four months) were divided into two groups: group one received anti-helminthic treatment and group two was the control, Ail animals were monitored monthly with respect to hematological parameters, eggs per gram of feces and culture of nematode larvae. In each group, there were significant differences between erythrocyte counts, hemoglobin concentration and hemotocrit over the period. Total leucocytes, neutrophils and eosinophils increased and lymphocytes decreased during the rainy season. No significant differences were observed between the two groups. In both groups, egg counts decreased as the animals aged and significant differences between the two groups were observed after the rainy season. The most common nematode larvae obtained from culture was Cooperia followed by Haemonchus, Oesophagostomum Trichostrongylus e Bunostomum.