Rotavirus is the most common cause of calf scour, which usually affects calves when they are between five and 14 days old.
One of the main causes of a rotavirus infection is carrier cows, who show no signs of the virus but shed the virus to the calf after calving.
Rotavirus is common in herds; although some herds are vaccinated against the virus, where as others are not.
Symptoms include:
- A pale yellow calf scour sometimes containing specks of blood;
- Calves are weak and slow to get up or fail to get up at all;
- May drool and can struggle or fail to pass faeces.
Older calves (greater than four weeks) can become reinfected but show no signs or symptoms of the virus.
Treatment for calf scour
Infected calves should be isolated and housed in a warm environment or kept warm with a calf jacket or a red light.
It is paramount that infected calves are kept hydrated with water and electrolytes – to correct dehydration and electrolyte imbalances.
Sick calves should be given 3-4L of electrolytes – spaced out evenly throughout the day – along with their daily feed of milk or milk replacer.
In extreme cases intravenous fluids may be needed and your vet should be promptly called if this is the case.
A treatment of antibiotics can be administered to prevent any secondary infection.
Prevention
Rotavirus can be prevented through the vaccination of the herd. A one-shot vaccine given between three and 12 weeks before calving ensures that the cow’s colostrum contains antibodies that protect against three of the main causes of scour – rotavirus, coronavirus and E. coli.
If you have an outbreak and your herd is not vaccinated, one preventative method is through feeding newly-born calves colostrum from a vaccinated herd.
However, if you decide to do this you must ensure that the colostrum is coming from a fully vaccinated and disease-free herd.
If you have a scour outbreak on your farm it is important to be mindful of the fact that there are different types of scour. Diagnosing the correct cause of the scour will enable the most effective course of treatment.
