by: Megan Miller, Professional Services Veterinarian, ANIMART
Scours is the primary cause of calf death before weaning. It can be a devastating disease infecting many animals, resulting in expensive treatments and negatively impacting the animal’s long-term health and performance.
Signs of scours include the following:
- Diarrhea, sometimes with blood or mucus
- Rough hair coat
- Weight loss
- Sometimes fever
Four main causes of scours
The four main causes of scours are bacterial, viral, protozoal and nutritional. If unable to perform a necropsy and lab samples, look for the following distinguishing features to help pinpoint the pathogens, especially when calves break with diarrhea. See Table.
Factors that contribute to scours
- Difficult calving
- Inadequate amounts of or poor-quality colostrum
- Dirty environment
- Weather extremes
|Cause of scours||Special agent||Age of onset||Distinguishing features|
|Bacterial||E. coli||Less than 5 days||Septicemia (blood poisoning), secere diarrhea, sudden death|
|Salmonella||Anytime||Blood/mucous in feces, high fever, pneumonia|
|Viral||Rotavirus||5 days – 2 weeks||Often paired with another cause|
|Coronavirus||5 days – 3 weeks||Sneezing, coughing, runny nose|
|Protozoal (parasites)||Cryptosporidium||1 – 4 weeks||Long-lasting diarrhea (over 2 weeks)|
|Coccidia||1 – 6 months||Blood/mucous in feces, overcrowded, thing, unthrifty|
|Nutritional||Poor quality milk replacer||Anytime||Otherwise healthy|
Prevention of scours can be difficult, but there are strategies that can optimize calf health.
- Encourage the absorption of antibodies via the calf’s mouth and gut.
- Administer antibodies through vaccination of the cow so the cow’s colostrum is full of antibodies.
- Feed the calf high-quality colostrum or colostrum replacer (containing over 150 grams of immunoglobulin G) within the first 12 hours of life, when the calf’s ability to absorb antibodies is at its highest
- Consider using products that supply antibodies to the calf, helping it fight off bacteria, viruses and toxins.
- Sanitation is the other means to prevent scours. Remember, a calf explores its environment with its tongue, and the causative agents of scours are contracted orally. Investigate the following areas of your operation:
- Calving pen
- Colostrum milking buckets/hoses
- Esophageal feeders
- Bottles and nipples
- Feeding buckets
- Hutches and pens