Abstract

A cross-sectional study was carried out to determine the prevalence and risk factors associated with ovine gastrointestinal nematode infestation by faecal examination of 408 sheep from five different sites in and around Asella, South Eastern Ethiopia. The mean eggs per gram (EPG) count determined using modified McMaster technique showed that 73 (30.04%) of the sheep were lightly infested, 98 (40.34%) moderately infested and 72 (29.62%) heavily infested. Out of the total sampled sheep, 278 (68.1%) had a gastrointestinal nematode infection. Strongyles were the most frequently (64.0%) recovered nematode eggs followed by Strongyloides (7.4%) and Trichuris species (3.7%). The prevalence of gastrointestinal nematode infection showed a significant difference (p < 0.05) between young and adult age groups, and animals with poor body condition had a significantly higher worm egg count (p < 0.05) than those sheep in moderate or good body condition. There was significant association between the gastrointestinal nematode infection and animals with different age group, and body condition. In addition, there was a significant difference (p < 0.05) in prevalence among months of the study period. There was no significant difference (p > 0.05) in prevalence between sexes and different study sites of the subject area. Due to its important health problem and impact on production in the study area, emphasis should be given for the control and prevention of gastrointestinal nematode infection with further studies on species identification and larval ecology.

Key words: Asella, eggs per gram (EPG), gastrointestinal nematode, ovine, prevalence, risk factor.