Over the course of spring, many dairy farmers have held on to dairy-bred calves to feed them milk in a bid to reduce their superlevy bill.

With the milk quota year ending at midnight on 31 March, large numbers of reared and half-reared dairy-bred calves are expected to hit the market, particularly in the south of the country.

Farmers and buyers need to be wary of the implications the previous feeding regime has had on the development of the calves’ digestive systems.

Source healthy calves

Sourcing the right type of calf is crucial for any calf-to-beef system. Buying poor-quality calves will result in lower carcase values, while buying in dull or sick calves could result in disease outbreaks on the farm.

Calves should be healthy and alert, and have a clean, dry and shiny coat. They should have no discharge from the nose or mouth, show no signs of dehydration or scour and have a clean, soft naval which is not sore to touch.

Find out feeding regime

Farmers should be particularly weary of those calves sold in the next week or two. In many cases, farmers fed milk to calves on an ad-lib basis.

With little or no meal intake, you can be assured that rumen development in calves like these is limited and, for that reason, these calves in general are unfit for weaning for a further few weeks.

Farmers buying calves in large numbers direct from farms are in a better position.

When doing this, make sure to ask what feeding regime the calf was on. Ideally, a gradual change in diet is required.

Management on arrival

For anyone buying calves, it is always advisable to feed them approximately two litres of electrolyte solution once they arrive on farm, particularly if they have travelled a distance.

This should be followed up with a milk/milk replacer feed in the evening. Continue to feed the electrolyte solution once a day for the first two days the calves are on the farm.

Calves should be housed in a separate airspace to other stock to safeguard against the spread of disease. Slow and fast drinkers should be grouped separately if fed with a feeder that does not have individual divides for each calf or if fed in group troughs.

A suitable vaccination programme should be introduced, depending on the health status of farms the calves are coming from and the herd health history on the farm on which they will be reared.

Adjusting the diet

As with all changes in the diet, it should be done on a gradual basis to reduce the risk of dietary upsets.

Where calves have been fed milk ad lib, the calves’ milk intake needs to be reduced to five to six litres per day gradually over three to five days before switching to milk replacer.

In calves fed milk ad lib, the rumen is relatively undeveloped. While reducing the milk feed, ensure the calf has ad-lib access to meal and fresh water.

For calves that have not had previous access to water, let them have access to it directly after a feed, when their appetite will be decreased and the chances of them gorging on water is low.

Monitor meal intake and replace with fresh concentrates morning and night.

As concentrate intake level increases, the calf can have its milk replacer feeding level reduced to three litres per day for five days and then weaned.

Milk to milk replacer

Milk replacer is usually a cheaper feed than whole milk. As quota ends, there will be a movement to introduce milk replacer into the diets of young calves.

Milk replacer is not the same as whole milk, and for that reason a seamless change in diet is required.

To avoid dietary upsets, it is crucial that the timing of the feeding regime is kept the same – morning or night.

Ensure that the milk replacer is mixed at the correct temperature of 36°C to 38°C. Ensure that the milk replacer is measured accurately to avoid variations in concentration. The powder should be thoroughly mixed and not contain lumps.

Many farmers will consider switching to once-a-day feeding to reduce labour. Ensure that the calf is accustomed to a morning and night feed of milk replacer before moving over to a once-a-day feed.

Intake - basis for weaning

Concentrates are the driver of rumen development. Studies have shown that calves need to be consuming about 1kg concentrates per day to ensure they have adequate energy intake to get them through weaning.

As mentioned previously, access to an unlimited supply of fresh, clean water and hay during this period is crucial.

Where calves are not consuming the target level of concentrates, consider postponing weaning for a week.

When weaning, ensure that the groups and management remains the same. Avoid abrupt weaning and mixing of stock into larger groups. Grouping can take place a few days after weaning when calves are acclimatised to the new diet.