Assessment of Parasite Burden and Anthelmintic Resistance in Small Ruminants

Thesis Abstract

Small ruminants are essential for the livelihoods of smallholder farmers, yet the productivity and health of these animals are significantly compromised by parasitic infections and the increasing prevalence of anthelmintic resistance. The widespread reliance on conventional anthelmintic drugs has led to escalating resistance, undermining control programs and threatening sustainable sheep and goat production systems. This study aims to assess the current parasite burden and evaluate the extent of anthelmintic resistance among small ruminants in a semi-arid farming region characterized by diverse husbandry practices. The specific objectives are to quantify gastrointestinal parasite loads in sheep and goats, determine the effectiveness of commonly used anthelmintics, identify the prevailing parasite species, and explore farmers' perceptions and practices related to parasite control. Employing a cross-sectional research design, the study selected a sample of 300 smallholder farmers through stratified random sampling, ensuring representation across different herd sizes and management systems. The population comprised sheep and goats aged between 6 months and 2 years from five districts within the region. Data collection involved both qualitative and quantitative approaches fecal samples from 600 animals were analyzed using faecal egg count reduction tests (FECRT) to assess deworming efficacy, while parasitological identification was conducted through larval culture and PCR methods to determine species composition. Structured questionnaires and focus group discussions captured data on farmers’ knowledge, attitudes, and practices (KAP) concerning parasite management. The validity and reliability of instruments were established through pilot testing and Cronbach's alpha coefficients exceeding 0.8. Data analysis included descriptive statistics, analysis of variance (ANOVA) to compare parasite burdens across demographic variables, and logistic regression models to identify factors associated with resistance development. The FECRT results were interpreted in accordance with World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines to determine resistance status. Expected findings indicate a high prevalence of gastrointestinal parasites, particularly Haemonchus contortus and Teladorsagia circumcincta, with a significant proportion of farms exhibiting evidence of anthelmintic resistance, especially to benzimidazoles and ivermectin. The parasite burden varies significantly with management practices, grazing systems, and age groups. Farmers’ perceptions show limited awareness of resistance issues, and misuse or underuse of anthelmintics exacerbates resistance development. These findings will contribute critical insights into the epidemiology of small ruminant parasitism and resistance patterns in the region, filling important gaps in existing literature that predominantly focus on developed countries or different ecological zones. The study advances the theoretical framework of integrated parasite management by applying the Health Belief Model to understand behavioral factors influencing farmers' practices. It also tests the applicability of the resistance selection theory in a local context, providing empirical evidence for the mechanisms driving resistance. The main conclusion underscores the urgent need for sustainable control strategies, including targeted selective treatment, integrated pasture management, and farmer education campaigns. Recommendations based on the findings advocate for routine Surveillance of parasite burdens and resistance status, implementation of integrated parasite control programs, and policy support for farmer training and access to diverse anthelmintic classes. The study contributes to a deeper understanding of parasite dynamics and resistance ecology in small ruminants, informing both local and broader regional control efforts and fostering sustainable livestock production. Further research is recommended to explore molecular mechanisms of resistance and evaluate the long-term impact of integrated management strategies on parasite control efficacy.