“What’s more, there is a large amount of important early life development in the pre-weaned phase. The development of both mammary cells and the gut – and metabolic programming – all take place during this crucial early life period, so feeding high levels of milk enables us to take full advantage. It’s also the time when feed conversion efficiency is at its highest.”

Tomas explains that feeding the right amount of a well-mixed, proven calf milk formula is crucial when making the most of the early life growth potential.

“Both ingredients and volume of milk fed can affect feed efficiency; the more digestible your milk replacer, the more efficient it will be at delivering growth.

“A milk replacer’s digestibility is influenced by the type of protein and fat source used, along with its manufacturing process. Consequently, it always pays to buy a calf milk replacer from a trusted supplier.

“Provided your colostrum management and feeding protocol is sound – and your calves have access to fresh water, roughage and a palatable starter concentrate – we know that feeding a good heifer calf up to 900g (750g minimum) of calf milk replacer daily will allow you to meet optimum rearing targets. The peak milk allowance (6-8 litres per day in maximum 3L feeds) should be reached by two weeks of age. Indeed, these feeding levels are absolutely crucial if you want to calve heifers down with an adequate body size at 24 months,” he says.

Mitigating cold weather

During cold weather, growing heifer calves may need to be fed even more milk. “When temperatures fall below 15°C, calves under three weeks of age need more feed to hit growth targets and boost immunity,” Tomas says.

“Under mild weather conditions (15°C-25°C), for dairy calves to grow at an average of 750g per day in their first few weeks of life they need to be fed at least 750g of milk per day alongside dry feed and water.

“But when the temperature plummets you need to feed more. And if the temperature drops below freezing, daily energy requirements increase by up to 30%.”

He adds that high moisture levels or draughts just exacerbate the problem. “In fact, draughts of just 5mph can make calves feel 8°-10°C colder.

“When it comes to milk feeding in cold weather, you really need to step up the level of milk solids by 100g per day for every 10°C temperature drop below 20°C.

“This is best achieved by feeding milk more frequently and, in fact, this only mimics natural feeding behaviour when the weather gets colder. If calves are given the choice, they will feed at least three times a day – and if given free access to milk, possibly up to 10 times a day – drinking little and often.”

In addition, Tomas says that when temperature drop, keeping bedding plentiful, clean and dry is also important, consider the use of thermal calf jackets too, he adds.

For further information on calf nutrition, contact your local Volac business manager or visit feedforgrowth.com.