Rumen drinking in milk fed dairy calves
Rumen drinking and secondary acidosis is a problem of artificially reared calves, which we see fairly commonly in the post mortem room and have seen a few cases recently. These may be one off cases, but in some herds it can occur in a larger proportion of calves.
Clinical findings are suggestive of the condition, and include reduced feed intake, poor growth rate, rough hair coat, abdominal pain, rumen and abomasal bloating and pasty faeces. Quite often it is a profound acidosis without severe dehydration which is the eventual killer.
On post mortem examination, the rumen contents are pale yellow to white, and are malodourous. The presence of milk in the rumen causes an acidosis and inflammation and hyperkeratosis of the rumen mucosa. This exacerbates the problem, as inflammation hampers the closure of the oesophageal groove. There may be rumen ulceration present, and secondary bacterial and fungal infection may occur.
There are also a number of factors which can predispose to ruminal drinking on a group basis. They include:
- Neonatal diarrhoea
- Irregular feeding times
- Infrequent feeding
- Low quality milk replacer
- Drinking from an open bucket rather than a teat and drinking too quickly
- Too low a temperature of milk or milk replacer – ideally milk should be fed around body temperature (39°C)
- Height of feeding – the teat should be placed at about nose height for calves
- Stressors – transport, changes in groups, underlying disease
Ensuring good, consistent feeding practices and hygiene will minimise the number of calves affected. It is worthwhile considering this condition in calves with the clinical signs listed above, as it can have a significant effect on welfare and productivity.