Abstract

Parasitic infections represent one of the most prevalent and economically significant diseases affecting livestock worldwide. The present study aimed to investigate risk factors associated with liver fluke and lungworm infections in small ruminants, characterize the diversity of lungworm species, and determine the prevalence of infections in Kirkuk, Iraq. The study was conducted from November 2023 to April 2024 in Northeastern Iraq, examining 30,900 sheep, 797 goats, 9,990 cattle, and 84 buffalo at slaughter. All carcasses underwent thorough gross pathological examination to detect parasitic infections, including lungworms, liver flukes, hydatid cysts, and associated pulmonary lesions. Distinct pathological manifestations were particularly evident in naturally infected local sheep. The present study revealed the following disease prevalence patterns across species. Pneumonia was detected in 0.31% of sheep and 0.35% of cattle, with no cases observed in goats or buffalo. Hepatitis showed an incidence rate of 0.39% in sheep and 0.75% in cattle. Hydatid cyst occurrence in hepatic and pulmonary tissues was documented at 0.38% in sheep and 1.13% in cattle, while remaining undetectable in caprine and bovine specimens. Liver fluke infection rates varied significantly among species, with sheep exhibiting 0.32% prevalence, goats demonstrating the highest rate at 3.76%, cattle showing 0.90% infection, and buffalo populations remaining completely uninfected. The present findings revealed significantly higher disease susceptibility in ruminants during winter months, with progressively lower infection rates observed throughout summer and monsoon seasons. This seasonal pattern may reflect environmental factors influencing parasite life cycles and host immunity.