Review calf milk solids as temperatures drop

Dairy farmers are being urged to measure calf milk solids and make adjustments according to the weather to avoid poor growth rates and a dip in immunity.

In colder weather, when insufficient energy is fed, calves will use energy to maintain body temperature rather than for growth, warns Keith Cutler from Endell Veterinary Group.

Winter milk feeding top tips
  • In colder weather calves need more energy
  • Amount of energy required depends on breed, metabolic demands and environment
  • When the temperature drops below 15C, milk solids should be increased by about 100g for calves under 12 weeks old
  • Make changes slowly
  • Good hygiene essential

 “If a calf is struggling to keep warm, let alone grow, there will be insufficient energy to ensure that its immune system can function properly, so it will be more susceptible to a wide range of infectious diseases than if it was receiving an adequate level of nutrition,” explains Mr Cutler.

The amount of energy required for thermoregulation varies depending on the breed, environment and metabolic demands of the calf.

Vet Kathy Hume from Westpoint Veterinary Group advises following the manufacturer’s guidelines on dilution rates.

However, at times when increased energy may be needed, such as periods of cold weather, farmers should discuss a feeding plan with a vet or nutritionist to gradually increase concentration of milk solids and avoid nutritional scours.

“For calves under 12 weeks old, if the temperature were to drop below 15C, milk solids should be increased by about 100g into daily feed as this age group are more sensitive to temperature changes,” says Miss Hume.

Milk replacer should contain milk-derived proteins, about 20-26% crude protein to support growth and 18-22% fat. The optimal protein percentage in milk replacer is linked to the feeding rate. Farmers must ensure calves are receiving sufficient volume of milk to make best use of protein – a restricted intake will result in poorer growth rates.

“Get the balance right between volume and concentration of milk. Calf management should be meticulous – pay attention to detail and don’t make changes too quickly,” she says.

When mixing and feeding calf replacer, Mr Cutler says consistency is key, including volume, temperature, dilution and frequency of feeding.

On one client’s farm, Mr Cutler saw unthrifty calves. At feeding time the farmer believed he was adding 100g/litre, but in reality, once the scoop of powder was measured, he was actually only mixing 45g/litre.

“Farmers need to be certain of what they should be feeding and then certain they are feeding it,” says Mr Cutler.

Another benefit of getting milk solids right is stronger immunity and at this time of year, when calves may be under many stresses, this can be invaluable.

Hygiene is frequently an issue and strongly linked with calf immunity. “A good start would be to make sure calves are kept clean, dry, well bedded up and in a draught-free environment,” he adds.