Insights into Bovine Viral Diarrhea Epidemiology in Moroccan Cattle Population.

This study aimed to estimate the seroprevalence of bovine viral diarrhea virus (BVDV) in Moroccan cattle and to investigate associations with age, sex, breed, housing system, and geographic region. A total of 545 serum samples were randomly collected from cattle across various Moroccan regions between December 2023 and February 2024. Antibodies against BVDV were detected using a commercial competitive ELISA, and herd-level data were gathered via questionnaire. Overall, 25.0% (95% CI: 21.4 - 28.8) of samples tested seropositive. The highest prevalence was observed in the Tanger-Tetouan-Al Hoceima region (44.0%; 95% CI: 24.4 - 65.1), followed by Casablanca-Settat (32.6%; 95% CI: 26.1 - 39.6). Seropositivity was highest among cattle older than 12 months (37.5%) and in crossbred animals (86.1%) compared to purebreds (74.3%). Although not statistically significant, cattle in intensive systems showed higher prevalence (29.3%) than those in semi-intensive systems (23.2%). Females exhibited a higher seroprevalence (27.87%) than males (21.7%), with sex emerging as a significant risk factor. These findings highlight the widespread circulation of BVDV in Morocco and underscore the need for targeted control measures and improved herd management practices to mitigate virus transmission.