Epidemiological studies of parasitic gastrointestinal nematodes, cestodes and coccidia infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

D.M Pfukenyi,A.L Willingham,S Mukaratirwa,J Monrad

doi:10.4102/ojvr.v74i2.132

Abstract

Between January 1999 and December 2000 faecal samples from 16264 cattle at 12 dipping sites in the highveld and nine in the lowveld communal grazing areas of Zimbabwe were examined for gastrointestinal (GI) nematode and cestodes eggs, and coccidia oocysts. Strongyle larvae were identified following culture of pooled faecal samples collected at monthly intervals. The effects of region, age, sex and season on the prevalence of GI nematodes, cestodes and coccidia were determined. Faecal egg and oocyst counts showed an overall prevalence of GI nematodes of 43%, coccidia 19.8% and cestodes 4.8%. A significantly higher prevalence of infection with GI nematodes, cestodes and coccidia was recorded in calves (P < 0.01) than in adults. Pregnant and lactating cows had significantly higher prevalences than bulls, oxen and non-lactating (dry cows) (P < 0.01). The general trend of eggs per gram (epg) of faeces and oocysts per gram (opg) of faeces was associated with the rainfall pattern in the two regions, with high epg and opg being recorded during the wet months. The most prevalent genera of GI nematodes were Cooperia, Haemonchus and Trichostrongylus in that order. Strongyloides papillosus was found exclusively in calves. Haemonchus was significantly more prevalent during the wet season than the dry season (P < 0.01). In contrast, Trichostrongylus was present in significantly (P < 0.01) higher numbers during the dry months than the wet months, while Cooperia and Oesophagostomum revealed no significant differences between the wet and dry season. These findings are discussed with reference to their relevance for strategic control of GI parasites in cattle in communal grazing areas of Zimbabwe.

Highlights

In rural Zimbabwe, cattle are grazed on communal pastures throughout the year
The present study clearly demonstrated the effect of age on the occurrence of GI nematodes with the prevalence being highest in animals aged less than 12 months and lowest in adult cattle
Sometimes during late pregnancy, the immune response of the host to gastrointestinal nematodes is partially suppressed leading to an increase in the population of worms and at the same time the fecundity of female worms in previously immune hosts may increase to approach that of worms in fully susceptible animals (Connan 1976)

Summary

Introduction

In rural Zimbabwe, cattle are grazed on communal pastures throughout the year. The animals do not Accepted for publication 7 March 2007—Editor receive any supplement (Pandey, Chitate & Nyanzunda 1993) and fodder shortage is usually a problem, even in the rainy season (Moyo, Bwangomoi, Hendrikx & Eysker 1996). Vickers & Moyo 1992; Pandey et al 1993; Vassilev 1994, 1999; Moyo et al 1996). These studies have shown that the predominant parasites in cattle were Fasciola gigantica, amphistomes, and strongylid nematodes, with coccidia, Schistosoma mattheei, Moniezia spp. and Trichuris spp. being less prevalent. The diverse agroclimatic conditions, animal husbandry practices and pasture management have been shown to largely determine the incidence and severity of various parasitic diseases in a region (Jithendran & Bhat 1999). Information on the epidemiological patterns of the parasitic diseases in different agroclimatic zones of the country would provide a basis for evolving strategic and tactical control of these parasitic diseases (Jithendran & Bhat 1999)

Methods

Results

Conclusion