Research Article
Rahmeto Abebe, Mulugeta Mel
Abstract
This study was conducted between November 2010 to April 2011 to estimate the prevalence of lungworm infection in small ruminants, determine the parasite species and identify the potential risk factors in and around Wolaita Soddo town, Southern Ethiopia. Faecal samples were collected from 360 randomly selected small ruminants (204 sheep and 156 goats) and processed with the modified Baerman technique for the extraction of first stage larvae. Overall, 45 (22.1%) sheep and 30 (19.2%) goats were found infected with lungworms. No significant difference was observed in the prevalence of lungworm infection between sheep and goats (p>0.05). Dictyocaulus filaria was the single lungworm species identified in both sheep and goats. The risk factors analyzed were sex, age, management system (zero-grazing or free-ranging), deworming history and body condition score (BCS). Management system, deworming history and BCS were significantly associated with the prevalence of D. filaria infection in sheep and goats (p<0.05 for each factor). It was observed that the prevalence was significantly higher in extensively managed/free-ranging (OR=4.6 in goats), poorly conditioned (OR=5.3 in sheep; 6.1 in goats) and nondewormed (OR=4.8 in sheep; 6.1 in goats) animals. Sex and age had no significant effect on the occurrence of D. filaria infection (p>0.05). In conclusion, the association of lungworm infections with the management system and deworming status of the animals in the present study are as expected. The association of infection with BCS requires further research to investigate if improving the nutritional status, thereby improving BCS, will result in lower prevalence of lungworm infection. Also, as the present sample size is thought to be small, further study with a larger sample size is required to determine the effect of age and host species difference in susceptibility to lungworm infection. One of the limitations of this study is that it is a one season survey and thus, a further year-round investigation is warranted to establish the association between seasonal variation and infection.