У 69,5% телят выявлены антитела к коронавирусу: рост рисков респираторных заболеваний

8 September 2026 | by FarmingUK Team | News, Dairy, Animal Health, Nearly seven in 10 calves screened over four years showed evidence of exposure to bovine coronavirus, underlining growing concerns about the virus’s role in respiratory disease. Analysis of 1,732 calves screened between 2022 and 2026 found 69.5% had antibodies to bovine coronavirus. The figures come from MSD Animal Health’s bovine respiratory disease screening service and indicate previous exposure or an immune response to the virus, rather than necessarily confirming active infection. Coronavirus-positive groups were also significantly more likely to show evidence of other respiratory pathogens, particularly bovine parainfluenza virus type 3, known as PI3, and Mannheimia haemolytica. Each additional PI3-positive calf was associated with an approximately 37% increase in the odds of a group also being coronavirus-positive. MSD Animal Health veterinary adviser Dr Kat Baxter-Smith said the findings highlighted the complexity of bovine respiratory disease. “Seeing evidence of multiple pathogens within the same groups reinforces that BRD is rarely caused by a single pathogen,” she said. “It highlights the need for farmers to take a proactive, whole-farm approach to respiratory disease prevention.” Bovine respiratory disease is multifactorial, with infectious challenge combining with factors such as housing, ventilation, immunity, nutrition and general calf management. Bovine coronavirus may play a role early in the disease process by affecting the protective lining of the respiratory tract, potentially making it easier for other pathogens to contribute to disease. The findings also raise concerns about subclinical BRD, where lung damage can develop without obvious outward signs. While clinical BRD typically affects around 11% to 16% of calves, research cited by MSD suggests subclinical disease may affect between 23% and 67%. “By the time coughing, nasal discharge or increased respiratory effort become apparent, lung damage may already have occurred,” Dr Baxter-Smith said. Even relatively small lung lesions can affect calf performance. Research cited by the company found calves with lesions measuring 1cm to 2cm had average daily gains between 96g and 138g lower than calves without lesions. “This is why understanding which pathogens are circulating and identifying risk factors on farm is so important,” Dr Baxter-Smith said. She added that vaccination should sit alongside good colostrum management, nutrition, housing, ventilation and hygiene as part of a wider prevention plan. BRD screening can help identify pathogen exposure and possible gaps in protection, while thoracic ultrasound can be used to detect lung damage and subclinical disease. MSD said protection against respiratory coronavirus can begin from birth with Bovilis Nasalgen-C, an intranasal vaccine licensed to reduce clinical signs of upper respiratory tract disease and nasal viral shedding associated with bovine coronavirus infection. “For farms where coronavirus is identified as part of the respiratory disease challenge, having the option to protect calves from the day of birth can be an important part of a wider prevention strategy,” Dr Baxter-Smith said. She stressed that vaccination alone would not prevent every case of respiratory disease. “Vaccination is not a silver bullet for respiratory disease, but it is an important part of a wider prevention strategy,” she said. “BRD results from a combination of infectious challenge and other risk factors, so prevention needs to focus on both reducing exposure and supporting the calf’s ability to withstand disease.” With respiratory disease often becoming more challenging during the autumn and winter months, farmers and vets are being encouraged to review BRD prevention plans ahead of winter housing. MSD Animal Health will host a BRD webinar on Monday 14 September, featuring a farmer using thoracic ultrasound scanning as part of respiratory disease management. A separate webinar for vets, “BRD in Practice: Prevention, Diagnostics and Emerging Risks”, will be hosted by The Webinar Vet on Tuesday 22 September.