Veterinary session

Bovine Respiratory Disease Complex (BRDC) is regarded to have a significant impact on the

beef and dairy industry globally due to the increased risks in mortality and morbidity in

calves, leading to economic losses in the farming industry. It is often considered a multi-

factorial disease caused by different stressors, bacterial and viral pathogens.

By the serological investigation of 100 blood samples collected from 3-12 months old calves

kept in 18 farms across Malta and Gozo islands, this study is surveying the presence and seroprevalence of Bovine orthopneumovirus (formerly known as Bovine Respiratory Syncytial Virus (BRSV)), Bovine respirovirus 3 (formerly known as Bovine Parainfluenza-3 Virus (BPIV-3)) and Bovine alphaherpesvirus 1 (BoHV-1), Pestivirus A and Pestivirus B (formerly known as Bovine Viral Diarrhoea Virus (BVDV)) in Malta. Furthermore, clinical signs were observed during sample taking, and a questionnaire collected general data from farmers.

The findings revealed 17%, 43%, 4% and 32% seropositivity on BRSV, BPIV-3, BoHV-

1 and BVDV, respectively and slightly more than one third (35%) of the sample tested negative for antibodies against all viruses. Within the age groups, the

seropositivity varied between 0-23%, 0-28%, 0-23% and 0-50% on BRSV, BPIV-3, BoHV-1

and BVDV, respectively. All age groups experienced one of the four scenarios: either the calves tested positive and showed clinical signs, the calves tested negative and showed clinical signs, the calves tested positive and did not show clinical signs or the calves tested negative and had no clinical signs. The results suggest that clinical signs are not to be overlooked but do not reliably indicate that the calf is sick for the BRSV, BVDV, BPIV-3 and BoHV-1 virus; moreover, national programs on regular serological surveys, preventive measures and education of the farmers is necessary.

This research is significant as it is the first documented study about BRDC in Malta. The

findings will aid farmers from an educational and economic perspective and contribute to animal welfare within the Maltese context in preventing the onset of the disease, controlling the disease, and preventing deaths. Based on these preliminary results, further research on a larger scale in Malta is recommended.