There are plenty of calves on the ground for the herds that are milking cows over the winter months, and calf scour is always a call for concern when managing young calves.
Scour is the biggest killer of young calves on dairy farms, and although completely eliminating cases on farms will be difficult, the number and severity of cases can be reduced.
Scour refers to watery faeces and results from a badly damaged gut, which leads to a loss in function and an intestine that is not functioning properly which causes the calf to lose salts and water in the form of diarrhoea.
The initial damage to the gut is caused by bugs, and once the damage is done, the calf will be scouring until the intestine is repaired.
Calf scour is most commonly caused by parasites such as cryptodporidia and coccidia, or viruses like rotavirus and coronavirus. It is less commonly caused by bacteria such as salmonella and Escherichia coli (E.coli).
Calf scour
Calves that are showing symptoms of scour should be separated from the group, as this will prevent the spread of the infection and give the calf a better chance to recover.
It is vital that the calf’s fluids and salts are replaced immediately. Healthy calves need up to 4L of fluids a day and scouring calves need an additional 4L to replace lost fluids.
The calf with scour should be given one or two extra feeds of about 2L each of electrolytes or some sort of good quality rehydration solution as soon as the calf starts scouring.
If the calf is too weak to suck or drink the electrolytes, the calf should be stomach tubed to get something into the system.
A scouring calf is losing fluid which needs to be replaced, so it is important to continue to offer milk feeds, along with extra feeds of electrolytes.
Previously, some farmers would have stopped feeding milk to scouring calves, but research has shown that offering calves their milk feeds can reduce the length of sickness and recovery time.
Feeding milk separately while the calf is sick actually helps with the healing of the intestine, so offering it to the calf for as long as they want to drink it should continue, and the milk should not be diluted.
Prevention
Feeding good quality colostrum is the key to calf scour prevention. Whether a calf stays healthy or gets scour is determined by the balance between the resistance of the calf and the level of infection it is exposed to.
Good hygiene is crucial as keeping the calf comfortable, dry and clean is important through all stages of calf rearing.
Cryptosporidia can cause severe diarrhoea in calves that have received adequate amounts of colostrum, but hygiene is poor.
Individual calf pens should be cleared out between calves and when calves are grouped together, they should be put into clean pens, as clean, dry bedding is essential wherever the calf is housed.
As the calving season progresses, there is a tendency for infection to build up, so it is important to ensure that your calf housing as clean at the end of the season as at the start.
Another thing that might get overlooked as the calving season goes on, is the cleanliness of the feeding equipment – make sure that all teats and buckets are thoroughly washed after every use.
