Managing bovine coronavirus-associated winter dysentery outbreaks to minimise welfare impacts.
Winter dysentery causes significant acute welfare impairment during outbreaks. The explosive onset of watery to haemorrhagic diarrhoea affects large proportions of the herd simultaneously. Cattle show depression, reduced appetite, and visible abdominal discomfort. Dehydration develops rapidly — the combination of diarrhoea volume and reduced water intake causes significant fluid and electrolyte losses.
The welfare impacts extend beyond the acute illness period. Significant body condition loss occurs during outbreaks. Milk production drops dramatically and may not fully recover. The systemic illness of an acute viral diarrhoea is distressing for affected animals, even when the disease is self-limiting.
Supportive care — ensuring adequate water, electrolyte supplementation, and comfortable housing — is the mainstay of treatment. Isolation of severely affected cattle and enhanced hygiene reduce spread within the herd. BCoV vaccines are available in some countries and may reduce outbreak severity, though evidence is mixed.