Bovine coronavirus commonly found in calf respiratory screenings
There may be a link between respiratory infection and intestinal infection.
Bovine coronavirus (BCoV) has become the most common virus found in routine screenings conducted during calf respiratory disease outbreaks, UK studies have shown.
Calf serology on 59 UK farms with history of respiratory disease issues between 2021 and 2022 revealed that 91.5 per cent of samples were positive for BCoV.
Calf respiratory disease is considered to be widespread, and has been highlighted as a critical area for overuse of antibiotics. MSD Animal Health say that there is an under use of vaccination in the UK cattle sector.
There are also concerns that there may be a link between respiratory infection and intestinal infection, as the virus is produced in the respiratory tract and then swallowed with excess mucus generated by the infection.
Speaking at the National Youngstock Conference, Dr Kat Baxter-Smith from MSD Animal Health UK called for veterinary practitioners and the UK cattle industry to take bovine coronavirus more seriously, just as human health experts changed their mindset during the Covid-19 pandemic.
Dr Baxter-Smith said: “While BCoV is a relatively well-known cause of neonatal calf diarrhoea – and the same virus as the respiratory variant – its role and impact in calf pneumonia has been less well defined. However, our latest diagnostic data certainly shows its overwhelming presence during calf respiratory disease outbreaks in the UK”
She added that BCoV is frequently isolated against other respiratory disease pathogens, such as BRSV, M. haemolytica, Pi3 and M. bovis, which may suggest interplay between the organisms.
Dr Baxter-Smith continued: “Research has already shown that BCoV infection disturbs the protective mucus lining of the thoracic tract. It may therefore be that BCoV ‘open the doors’ for the other viral and bacterial pathogens to establish themselves and cause disease.
“Whilst the pathogenicity of BCoV within the BRD complex remains an unknown quantity, its ubiquitous presence in the UK cattle population – and the recent human experience of coronavirus as a significant respiratory pathogen – suggests the need for some re-evaluation.”
Defra has published guidance for the vet sector ahead of a proposed UK-EU Sanitary and Phytosanitary agreement.
