Detection of Bovine Viral Diarrhoea Virus in a Case Series of Clinically Cachectic Cattle from Tiaret, Algeria.

Bovine viral diarrhea virus (BVDV) poses a serious disease in cattle. Cachexia is a condition marked by weight loss and muscle wasting and is often observed in infected animals. This study reports a case series from Tiaret province, Algeria, aimed at detecting and genetically identifying BVDV in clinically cachectic cattle. A total of 100 cachectic animals from ten herds were examined using serological, molecular, and virological methods, including antibody ELISA, RT-qPCR, and virus isolation in cell culture. Overall, 93.6% of the animals tested were seropositive for BVDV, indicating extensive exposure to the sampled population. Higher antibody rates were observed in adults (≥12 months) and males compared to younger animals and females, but the differences were not statistically significant. Phylogenetic analysis of the 5'UTR sequences confirmed the presence of the BVDV-1f subtype closely related to sequences reported in Europe. Although BVDV was detected in animals within the sampled herds, the data does not support a causal conclusion that BVDV was the direct cause of cachexia in this case series; rather, its immunosuppressive effects may predispose cattle to secondary infections contributing to wasting. These results are specific to this opportunistic case series from Tiaret province and should be considered exploratory; broader and representative surveillance is required to assess the national epidemiological situation.