Calf Scour: Welfare Management and Prevention

Key Welfare Considerations

• Calf scour is caused by pathogens including rotavirus, coronavirus, Cryptosporidium, and E. coli K99.
• Rotavirus is the most common viral cause — vaccination of cows pre-calving provides colostral antibody welfare protection.
• Cryptosporidium parvum causes profuse watery diarrhoea in 1-3 week old calves with significant welfare impact.
• Dehydration from scour causes rapid welfare deterioration — assessment of skin tenting and eye position guides severity.
• Mild scour calves that remain standing and have suck reflex can be treated with oral electrolytes for welfare.
• Oral electrolyte therapy is the primary welfare treatment — isotonic formulations with glucose and glycine aid absorption.
• Severe scour with loss of suck reflex requires intravenous fluid therapy as an emergency welfare intervention.
• Sodium bicarbonate in IV fluids corrects metabolic acidosis — a critical welfare parameter in severe cases.
• Milk feeding should continue during scour treatment — withholding milk worsens welfare outcomes.
• Antimicrobials are indicated only for calves with systemic signs — targeted use reduces AMR welfare concerns.
• Hygiene management including clean calving pens and isolation of scouring calves reduces transmission welfare risk.
• Colostrum management — ensuring adequate intake within 6 hours of birth — is the most important prevention welfare measure.
• Colostrum quality testing with a Brix refractometer guides supplementation decisions for welfare protection.
• Halofuginone is licenced for Cryptosporidium control — early treatment reduces welfare duration and severity.
• Herd vaccination programmes and improved hygiene have the greatest welfare impact on calf scour mortality.