Capillaria, Ascaridia, and Heterakis are among the economically significant Gastrointestinal Nematodes (GINs) that significantly affect the health and productivity of poultry. Anthelmintic resistance is one of a big challenge in the control of animal parasites including poultry. Proper diagnostics and good knowledge of the epidemiology are essential for the development of an effective deworming strategy. Thus, this PhD research project aims to evaluate the epidemiology of Ascaridia, Capillaria and Heterakis in different poultry production systems in Ethiopia based on copromicroscopy and serology. Finally, the efficacy of fenbendazole and levamisole deworming programs will be evaluated.