Sameh Baghezza - Department of Veterinary, Institute of Veterinary and Agronomic Sciences, University of Batna۱, Batna, Algeria.
Abdennour Azizi - Department of Veterinary, Institute of Veterinary and Agronomic Sciences, University of Batna۱, Batna, Algeria.
Fawzi Derrar - Viral Respiratory Diseases Laboratory, National Influenza Center, Pasteur Institute of Algeria, Algiers, Algeria.
Mustapha Adnane Smadi - Department of Veterinary, Institute of Veterinary and Agronomic Sciences, University of Batna۱, Batna, Algeria.
Hanene Djeghim - Biochemistry Laboratory, Center for Research in Biotechnology (CRBt), Constantine, Algeria.
Khireddine Ghougal - Laboratory of Health Management and Animal Production (LHMAP), Institute of Veterinary Sciences, University of Constantine۱, Constantine, Algeria.
El Alia Gradi - Viral Respiratory Diseases Laboratory, National Influenza Center, Pasteur Institute of Algeria, Algiers, Algeria.
Omar Bennoune - Department of Veterinary, Institute of Veterinary and Agronomic Sciences, University of Batna۱, Batna, Algeria.
Bakir Mamache - Department of Veterinary, Institute of Veterinary and Agronomic Sciences, University of Batna۱, Batna, Algeria.

Background: Respiratory viral diseases, including the bovine parainfluenza ۳ virus, cause significant economic losses in ruminants. There is no available data regarding the epidemiological situation of this virus in Algeria. Objectives: The present study aims to determine the seroprevalence and the associated risk factors of bovine parainfluenza ۳ virus (BPI۳V) in sheep in two different climatic regions of Algeria. Methods: A total of ۱۰۸ serum samples were collected from sheep at different ages and tested for antibodies against BPI۳V using an indirect enzyme-linked immunosorbent assay (ELISA). A real-time polymerase chain reaction (PCR) test was also performed on nasal swabs to detect the viral genome. Results: At the animal level, out of ۱۰۸ sera tested, ۸۲ (۷۵.۹۳%, ۹۵% CI, ۶۶.۷۵%, ۸۳.۶۳%) showed antibodies against BPI۳V. At the herd level, all ۲۳ herds tested (۱۰۰%) had at least one animal with BPI۳V antibodies. Our results showed no association between the presence of BPI۳V antibodies and the region (P=۰.۷۲). However, at the herd level, risk factors such as flock size and predisposing factors like climate change, feed deficit, postpartum stress, and dust were identified. At the animal level, a highly significant association was found between BPI۳V seroprevalence and the age of the animals (P<۰.۰۰۰۱). Notably, the sheep group over ۳ years was more susceptible than other age groups. Furthermore, a significant difference in BPI۳V seroprevalence based on sex was observed (P<۰.۰۰۳). All collected nasal swabs were negative for BPI۳V genome detection using real-time PCR. Conclusion: This study is the first serological survey on BPI۳V in Algeria, confirming its presence in sheep from two regions. The high serum prevalence of BPI۳V observed in the study population highlights addressing this viral disease to mitigate economic losses in ruminants.

Algeria, Bovine parainfluenza ۳ virus, ELISA, risk factors, RT-PCR