Analysis of potential risk factors of caprine coccidiosis

Caprine coccidiosis represents a major concern in goat industry worldwide causing high economic losses, mainly due to poor weight gains, treatment costs and even death of kids. Therefore, analyses on risk factors involved in the establishment and outcome of this disease are important to improve infection status and herd management. In Portugal, approximately 400,000 goats are reared every year. The majority of them are allocated in the southern part of the country. In the current study, a representative number of animals (382 goats) and herds (37 herds) from Alentejo were monitored. Faecal samples from five young and five adult goats of each farm were collected rectally and examined individually by using the modified McMaster technique for oocyst counts (oocyst per gram of faeces - OPG). Additionally, a questionnaire on the husbandry conditions and anti-parasitic treatments was performed. Overall, a prevalence of Eimeria infections of 99% and 100% was detected on animal and herd level, respectively. Eimeria arloingi and E. ninakohlyakimovae as the two most pathogenic caprine species also constituted the most prevalent ones (34.91% and 29.90%, respectively), both in the young and the adult goat groups. As expected, OPG vales were significantly higher (p = 0.031) in young than in adult goats. Furthermore, risk factor analyses revealed young age, higher total number of animals on the farm and outdoor kidding as strongly associated with a higher risk of caprine coccidiosis. Overall, the high prevalence of pathogenic Eimeria species on Portuguese goat farms in combination with the occurrence of related risk factors strengthen the importance of coccidiosis control in caprine industry.