Morphological Characterization of Eimeria spp. Infecting Imported Sawakni Sheep Linnaeus, 1758 (Ovis aries) in Riyadh City, Saudi Arabia

Background: The epidemiology of parasitic infestations in sheep breeds is an important topic in meat production and human health. Protozoan parasites from the genus Eimeria cause coccidiosis. Coccidiosis ranks among the most perilous illnesses affecting sheep and other animals causing economic losses globally. Methods: The study was conducted to identify and study species of Eimeria in Ovis aries, in Riyadh City, Kingdom of Saud Arabia, from 1/1/2024 to 30/5/2024. A total of 1000 fecal samples of Ovis aries with different ages and genders were collected from Sheep markets and slaughterhouses in Riyadh city and employed morphological characteristics to accurately identify Eimeria spp. Result: The results showed 5 species of Eimeria that infect sheep: E. faurei (length 30±0.5 µm; width 22±0.12 µm), E. intricata (length 45±0.83 µm; width 34±0.37 µm), E. parva (length 17±0.56 µm; width 16±0.75 µm), E. granulosa (length 30±0.18 µm; width 20±0.31 µm) and E. pallida (length 17±0.50 µm; width 13±0.50 µm). Moreover, the results showed that the infection rate was 35.6%. Summer recorded the highest percentage at 46.8%, while winter recorded the lowest at 26.4%. The species, E. pallida recorded the highest infection rate of 7.70%, while the species E. intricata represented the lowest infection rate of 0.30%. The current study provides relevant information to assess potential infections and future defenses against sheep coccidiosis, thereby minimizing financial losses for Saudi Arabia’s sheep industry.