Enzyme-treated soy protein proves a match for dairy in CMR
Presented at the 76th EAAP Annual Meeting in 2025, a 2024 trial at Warmia and Mazury University (Poland) shows HP 100, an enzyme-treated soy protein, can replace up to 30% of dairy proteins in calf milk replacers without affecting growth or gut health.
Calves fed HP 100 CMRs matched the dairy control group in weight gain, while outperforming other vegetable proteins. This shows that milk proteins are not the only acceptable ingredient for CMR and supports HP 100 as a competitive and sustainable solution for calf nutrition.
Why milk proteins are no longer enough
CMRs have traditionally used dairy proteins for their amino acid content and digestibility. However, rising milk protein prices are increasing feed costs and squeezing producers’ margins. This is driven by market volatility, environmental issues and increased consumption in humans making milk protein less available for livestock nutrition.
In addition, the nutritional needs of the young calf in the liquid feeding phase remain those of a monogastric animal, as the oesophageal groove bypasses the rumen. Therefore, the amino acid balance and digestibility of CMR proteins directly affect growth and gut health outcomes.
Historically, vegetable proteins were considered unsuitable for calves due to anti-nutritional factors (ANFs) affecting digestibility. Advances in processing methods, such as HP 100’s enzymatic treatment, have resolved these issues. The result is a clean, digestible soy-based protein suitable for young calves.
University trial confirms performance of enzyme-treated soy protein
In 2024, Warmia and Mazury University tested 56 Holstein calves, validating HP 100 as an alternative protein source. Animals were placed into four treatment groups based on variations in the source of protein in their CMR formulation. Growth performance was monitored across three periods: early pre-weaning (0-30 days), late pre-weaning (30-75 days), and post weaning (75-135 days).
The results confirmed that replacing up to 30% of dairy protein in CMR with HP 100 maintained average daily gain (ADG) comparable to the full-dairy control group. HP 100 calves performed as well as the dairy group, even in the sensitive initial phase. Calves fed alternative vegetable sources such as hydrolysed wheat gluten or micronized soybean meal flour exhibited lower performance until weaning, showing an average liveweight deficit of around 5 kg. This equals about one week of lost growth.
Figure 1 – Average daily gain (ADG, g) from day 0-30, 30-75, 0-75, 75-135, and 0-135 after birth in calves fed calf milk replacer (CMR) formulas: standard skimmed milk powder (SMP), SMP partially replaced by enzyme-treated soy protein (HP 100), hydrolysed wheat gluten (HWG), or micronised soybean meal (μSBM). A, B indicates significant difference lower than P.
These findings demonstrate that HP 100, without compromising performance, makes a viable option for CMR formulations in the weaning transition.
Gut health outcomes: Better faecal scores and reduced ANFs
Beyond growth, gut health is key in calf management. Neonatal diarrhoea is still a leading cause of morbidity and mortality in dairy operations, often linked to undigested protein reaching the hindgut and disrupting microbial balance.
The trials assessed gut health by comparing faecal scores and ANF content in CMR across groups. HP 100 calves had firmer, more consistent stools and higher dry matter than those on conventional soy proteins, like the dairy-only group. These results suggest lower ANF levels in HP 100 reduce intestinal irritation and fermentation, as shown in the CMR analysis (Table 1).
A competitive and sustainable protein solution
HP 100 also offers economic and environmental advantages. The cost per unit of protein is lower than that of dairy proteins, particularly during times of market volatility. So, formulators can control CMR costs and still use high inclusion rates of quality protein.
HP 100’s high protein digestibility improves protein retention, reducing nitrogen excretion in manure. We must also remember that soybean is a legume, building its protein accumulation out of abundant atmospheric nitrogen and not from chemical fertilisers. These two HP 100 strong points align with sustainability goals increasingly demanded by producers and consumers.
This trial adds to evidence that HP 100 is a proven protein source for CMRs. By matching dairy protein growth, improving gut health, and cutting costs and emissions, HP 100 addresses key challenges in calf nutrition. It’s time to move beyond the ‘only milk counts’ assumption and embrace HP 100 as a science-backed alternative for future CMRs.
For more details about the trial data and how to incorporate HP 100 into your formulations, contact your Hamlet Protein representative.
Join 13,000+ subscribers
Subscribe to our newsletter to stay updated about all the need-to-know content in the dairy sector, two times a week.
