Abstract
Background:
In the north-west of Morocco, coccidiosis, caused by a protozoan of the genus Eimeria sp., poses a threat to the health of livestock, particularly sheep, and can sometimes lead to the death of animals, thus damaging meat production in the kingdom of Morocco. The research on this disease will allow livestock farmers to identify the most important and widespread species in the region, as well as the risk factors that influence the spread of this epidemic, so that precautionary measures can be taken to protect livestock.

Aim:
The objectives of this study were: To inventory the species of Eimeria (coccidiosis agent) infecting sheep reared in the north-west region of Morocco; to determine the rates of infection and excretion of oocysts; to identify the risk factors influencing the dynamics of coccidia (genus Eimeria sp.).

Methods:
A qualitative and quantitative coproscopic study was carried out on faecal samples collected directly from the rectum of 256 animals over a period of one year. Sex, age, date and season of sampling were recorded.

Results:
Four species of Eimeria were detected in the 256 sheep examined: Eimeria ovinoidalis, Eimeria prava, Eimeria ashata and Eimeria intricata, with an infection rate of 40.63% and an average number of eggs per gram of faeces of 4,887. The study showed an association between the disease and age and seasonal climatic changes (p < 0.05), while the sex of the animal had no influence on the spread of the disease (p > 0.05).

Conclusion:
Our study revealed important results concerning coccidiosis in sheep in the north-western region of Morocco. There was a strong association of infection with age and climatic changes, but no association with sex.

Key words: Eimeria; Sheep; Risk factors; Infection; Northwest of Morocco.