DAIRY PROTEIN IN CALF MILK REPLACERS: WHEY OR SKIM?

Whey protein concentrate and good quality skim are equivalent sources of dairy protein in milk replacers for pre-weaned calves. But beware low skim-based products because they simply won’t deliver comparable performance.

This was confirmed by independent trial work in 2019 at AFBI Hillsborough in Northern Ireland. Indeed, follow up studies at AFBI have now amplified the benefit of precision-formulated, early life pre-weaned calf nutrition on the performance of replacements right up to their third calving.

This AFBI work showed that the presence of skim – and therefore the clotting effect of casein – is not the fundamental element within a calf milk formula influencing optimum calf growth. If the important milk components are processed at low temperatures and with careful manufacturing techniques, both skim and whey proteins will be highly digestible by the milk fed pre-weaned calf and will deliver good performance.

However, the trial work has also shown that calf rearers still need to be discerning over calf milk replacer choice for rearing milking herd replacements.

What should you look for?

If favouring a skim-based calf milk replacer, always look for a high (>50%) skim content.  Lower skim formulation inclusions (e.g. 20-30% skim in the final formulation) won’t cut it. And if favouring a whey-based product, always be cautious about how whey protein is described when comparing milk replacer bag labels.

Skim milk powder is simply whole milk with the fat removed and contains 80% casein and 20% whey, whilst whey protein is a highly valuable co-product of cheese production. However, liquid whey from cheese production can be processed in a variety of ways, leaving different types of whey, including whey powder, delactosed whey and concentrated whey protein.

These different types of whey range in both protein and lactose content. For example, whey powder only contains 12.5-13% protein, compared to concentrated whey protein, which typically contains 35% protein. Consequently, concentrated whey protein is what you should be looking for on the label. Concentrated whey protein also contains important beneficial ingredients (such as immunoglobulins and lactoferrin) that help support the immune system, growth and development of the young calf.

FOUR KEY POINTS:

1. Feeding a good quality calf milk replacer, based on either concentrated whey protein or a high level of good quality skim (>50% inclusion) as the main protein source, will give good calf and heifer performance to weaning – and right through to third calving.
2. When a skim-based calf milk replacer is fed, a high level of skim (>50% inclusion) is needed to ensure a firm clot formation in the abomasum. Lower skim inclusion products simply won’t perform as well.
3. When comparing good quality calf milk replacers formulated on the above basis, there is no difference in physical properties.
4. Remember too that the manufacturing methods and processing temperatures of the raw ingredients are key because this will determine the quality of the protein fed to the pre-weaned calf.

For more information, please visit www.feedforgrowth.com