Calculating the energy needs of calves

Published 20 September 17

Milk ReplacerA new calculator will help farmers work out the amount of energy needed by calves from their milk replacer to ensure good regular weight gain.

Devised by the University of Nottingham, this easy to use calculator will give a better understanding of the energy sources in milk replacer and help farmers to provide optimum nutrition for their calves.

Ginny Sherwin, a PhD student from the University of Nottingham, explains that the idea of a calculator came about when teaching final year students, “There’s nothing like this freely available to farmers at the moment, so we decided to simplify and adapt our tool into something that is easy and quick to use.

“With this calculator farmers can now work out what their calves need to grow at a certain rate. It takes external factors into consideration, such as temperature and its impact on energy needs.”

The calculator, hosted on the AHDB Dairy website, allows you to put in the energy information from the milk replacer label and will work out the growth rate heifers are likely to achieve with the current replacer, along with the amount of solids required to meet desired growth rates. Farmers should be aiming to double birth weight by time of weaning, and achieve 50 per cent of mature weight by 12 months.

Andy Dodd, Technical Manager at the Agriculture and Horticulture Development Board (AHDB), says: “Energy is a critical nutrient in young calf nutrition, but it must be fed at correct volumes and in proper balance to fat and protein to provide optimal results, which we’re highlighting through our Calf to Calving initiative.

“This calculator, released to coincide with autumn calving, provides an easy tool to make sure calves get exactly what they need to grow at the optimum rate. Research shows that by reducing the age at first calving from the current average of nearly 28 months to 24 months saves about £344 in rearing costs per heifer.

“If the diet you are providing your calves has a risk of not achieving average growth rate of 0.7 to 0.8 kg per day up to weaning, then you should consult your nutritionist and vet.”

AHDB’s Calf to Calving initiative enables dairy farmers to achieve measured improvements in heifer rearing specifically in calf and heifer survival, growth, health, fertility and age at first calving. 

There are 12 host farms across Britain who are tracking 10 calves each from birth through to fist calving, measuring and monitoring survival, nutrition, growth, health and reproductive performance.