REVIEW MILK REPLACER FEED VOLUMES & FAT LEVELS TO MAKE EFFICIENCY GAINS

Calf rearers looking to make strategic efficiency gains in-light of lower milk price could benefit from reviewing calf milk replacer feeding volumes and fat levels.

Dr Jessica Cooke, R&D Manager at Feed For Growth (Volac Milk Replacers Limited), says tighter margins underline the importance of cost-effective calf growth. However, they should not be a reason to cut corners in the rearing stage or be tempted to feed whole milk to calves.

“It’s always worth investing in calf growth, whatever the milk price,” she explains. “Ultimately, you’re investing in your herd’s future. If you cut back now, you’re not making the most of high feed conversion efficiency during the milk feeding stage.”

However, she believes there is potential to be more cost efficient and boost performance by thinking about fat inclusion levels in calf milk replacers (CMR) and feeding volumes. Milk replacers of over 22 to 23% fat will likely cost more and can suppress starter intakes, which could have a detrimental impact on long-term performance.

Dr Cooke explains: “Feeding a CMR with a fat content of less than 22% typically stimulates the earlier consumption of solid feed. This is what you want because solid feed intakes pre-weaning stimulates rumen development, which is key to ensuring a smooth transition around weaning. Heifers with good rumen development will continue to grow well immediately post weaning which is an economical stage to grow heifers due to the lower cost of dry feed.”

A recent Canadian¹ study found that average daily liveweight gain was greater over a 91-day period for calves fed a 17% fat CMR, versus a 23% and 29% fat CMR. The CMR was a blend of 20% coconut and 80% palm fat at 26% crude protein. There were 128 male Holstein calves enrolled in the study.

Calves fed the 17% fat CMR had higher starter intakes pre and post weaning and consumed 33kg more starter by the end of the study compared to the 23% fat group. Average daily gain was also higher meaning their final body weight was 13.6kg more (see table). This improved performance is likely driven by increased nutrient intake from greater solid feed consumption, particularly post weaning.

Dr Cooke says it’s important to get the balance of milk and starter feed right. “Too much fat in your milk replacer in combination with high CMR feeding levels of around 90kg per calf adds cost to your system. It may mean your calves grow well and look amazing to begin with, but immediately post weaning, growth rates will likely crash because calves haven’t eaten enough starter. esearch suggests feeding 50-60kg of milk solids across the rearing period is the optimum.”

Dr Cooke believes thinking about fat levels and feeding rates is an easy win for improving efficiencies without increasing costs. It also acts as a much safer route than looking to lower costs by feeding whole milk to calves in-light of lower milk prices, which could inadvertently introduce diseases like Johne’s, Bovine TB and Mycoplasma bovis.

“A quality CMR is not only more hygienic but also has a more consistent macro and micro-nutrient supply for calves than whole milk and can provide additional health package benefits,” she adds.

Reference:

¹Lovatti, J. V. R., T. E. da Silva, A. J. Keunen, M. A. Steele, D. L. Renaud, and J. H. C. Costa. 2026. Effects of fat level and coconut-to-palm fat ratio in milk replacer on solid feed intake and performance of pre- and postweaning dairy calves.