The Truth about CMR, Part 4 - Health & Future Performance from Calf Nutrition

7 March 2018

In the fourth and final part of his in-depth look into the science and best practices of calf milk replacer, Trouw Nutrition Ireland's Jim Uprichard gives his advice and recommendations for optimal feeding strategies.


Feeding elevated CMR volume

Feeding elevated planes of nutrition (800 to 1200g of calf milk replacer, reconstituted at 150g/litre, to give 5.5 to 8 litres of milk/day), has shown to increase ADG, earlier onset of puberty, as well as increase milk production over multiple lactations (Soberon et al., 2012).

It was previously thought that the capacity of the abomasum was a maximum of 2 litres, and meal sizes greater than this would result in an overflow of milk into the rumen. This is not problematic for very young calves, as the rumen, reticulum and omasum are not yet developed, therefore milk will flow back into the abomasum within hours (Lateur-Rowet and Breukink 1983; Constable et al., 2006).  In calves older than 2 weeks old, the lactose from milk overflow into the rumen may potentially produce lactic acid, lowering rumen pH. This could affect rumen microflora, resulting in indigestion, diarrhoea and reduced growth (Sjaastad, Hove and Sand, 2010).

However, recent research has shown that the abomasum has the capacity to accommodate much higher volumes of milk than the 2 litres/feed (Ellingsen et al., 2016). In this study, it was shown that three-week-old calves can voluntarily consume up to 6.8 litres of whole milk in a single meal.  As the abomasum has the ability to expand, milk did not overflow into the rumen, and there was no signs of abdominal pain or discomfort (Ellingsen et al., 2016).

Studies have shown that calves fed these higher volumes of milk have no reduction in solid feed intake after weaning (Jasper and Weary, 2002; Uys et al., 2011). Rather, calves may be unable to meet their daily energy requirements (Nielsen et al., 2011) and suffer from chronic hunger (De Paula Vieira et al., 2008) if restrictive milk feeding is imposed during the first 3 to 4 weeks of age. Recent research suggests that an elevated plane of pre-weaning nutrition, combined with a step-down process to solid feed starting at 5 to 6 weeks old, and weaning and a later age, leads to optimal calf health and lifetime performance benefits (Meale et al., 2015; Eckert et al., 2015; Wood et al., 2015).

We recommend not reducing milk volume until 6 weeks of age as the energy contribution from the rumen will be insufficient to meet the needs of rapidly growing calf. When calves are fed larger meals, the rate of passage from the abomasum to the lower gut slows down, maintaining correct blood glucose control. This means that post-prandial hyperglycaemia is not an issue when feeding elevated volumes of calf milk replacer (MacPherson et al., 2016). 


Feeding strategies in cold weather

In cold weather conditions, the energy requirements for maintenance increase, while protein requirements do not change. When feeing calf milk replacer, these extra energy requirements can be met in a number of ways, such as: 1. Feed a milk replacer with higher fat content during winter months e.g. 20% vs 17% 2. Increase the volume of calf milk replacer e.g. feed by an additional litre per day (split over the number of feeds) up a maximum of 1200g of milk powder/day 3. Increase the concentration of calf milk replacer up to a maximum of 150g/litre 4. Add a third meal in per day.


Health through Nutrition

For many years it has been understood that the optimum health of the growing calf can only be achieved with optimum nutrition, which takes into account energy, protein, minerals and vitamins, as outline above. In addition, additives can have a positive influence on the calf’s productivity and immunity. Additives which have beneficial effects include intake stimulants, fat emulsifiers (which improve fat digestion), essential oils (antimicrobial properties, pulmonary clearing effects), yeast cell wall extracts (prebiotic) toxin binders (counteract feed mycotoxins) and rumen enhancers (improve rumen development by enhancing the development of beneficial microbes while suppressing harmful microbes).

By closely watching the cutting edge research, if new additives are shown to improve calf productivity and immunity, these will be added to our portfolio of products to optimize young calf growth and health.



EU legislation states that it is illegal to feed a pre-ruminant calf once per day, as this is unnatural and does not prioritize calf welfare. It may be argued that if calf milk replacer is fed once per day, if a calf is allowed free access to concentrate from the first days of life, this will meet the legal requirements. However, since concentrate consumption in the first few weeks is very low, this is not deemed enough to constitute a feed.

The following is a quote form a letter from the EU Commission in response to a request for clarification on the matter of once per day feeding:

“The obligation of feeding calves twice a day remains in all circumstances. For all veal calves and any calf under the age of 28 days, twice feeding with milk replacers is the only way to comply with point 12 of the Annex to the Directive because my understanding of the scientific opinion is that solid feed cannot constitute a sufficient energy supply for the animals. For calves beyond 28 days, it is necessary for the authorities to evaluate to what extent the quantity and the quality of solid feed provided can constitute a real second feeding in the context of the welfare of calves.”

From this statement it is obvious that during the first 4 weeks, concentrate feed is not sufficient to constitute a calves’ second feed. The legislation states that after a calf is 28 days old, once a day feeding can only be carried out only with an understanding of the nutritional requirements of the calf and the advice of a veterinarian.




Ø.V. Sjaastad, K. Hove, O. Sand, Physiology of Domestic Animals, 2nd ed. Scandinavian Veterinary Press, Oslo, 2010.

H.J. Lateur-Rowet, H.J. Breukink, The failure of the oesophageal groove reflex, when fluids are given with an oesophageal feeder to newborn and young calves, Vet. Q. 5 (1983) 68–74.   J. Jasper, D.M.Weary, Effects of ad libitummilk intake on dairy calves, J. Dairy Sci. 85 (2002) 3054–3058.

J.L. Uys, D.C. Lourens, P.N. Thompson, The effect of unrestricted milk feeding on the growth and health of Jersey calves, J. S. Afr. Vet. Assoc. 82 (2011) 47–52.

MacPherson, J.A.R., Berends, H., Leal, L.N., Cant, J.P., Martín-Tereso, J. and Steele, M.A., 2016. Effect of plane of milk replacer intake and age on glucose and insulin kinetics and abomasal emptying in female Holstein Friesian dairy calves fed twice daily. Journal of dairy science, 99(10), pp.8007-8017.

Ellingsen, K., C. M. Mejdell, N. Ottesen, S. Larsen, and A. M. Grøndahl. 2016. The effect of large milk meals on digestive physiology and behaviour in dairy calves. Physiology & Behaviour, 154: 169-174.

P.D. Constable, T. Wittek, A.F. Ahmed, T.S. Marshall, I. Sen, M. Nouri, Abomasal pH and emptying rate in the calf and dairy cow and the effect of commonly administered therapeutic agents, Proceedings of the 24th World Buiatrics Congress. Nice 2006, pp. 54–68.

H.M. Nielsen, I. Olesen, S. Navrud, K. Kolstad, P. Amer, How to consider the value of farm animals in breeding goals. A review of current status and future challenges, J. Agric. Environ. Ethics 24 (2011) 309–330.

A. De Paula Vieira, V. Guesdon, A.M. de Passillé,M.A.G. von Keyserlingk, D.M. Weary, Behavioural indicators of hunger in dairy calves, Appl. Anim. Behav. Sci. 109 (2008) 180–189.

Soberon, F., E. Raffrenato, R. W. Everett, and M. E. Van Amburgh. 2012. Preweaning milk replacer intake and effects on long-term productivity of dairy calves. J. Dairy Sci. 95:783–793. http://

S.J. Meale, L.N. Leal, J. Martín-Tereso and M.A. Steele, ‘Delayed weaning of Holstein bull calves fed an elevated plane of nutrition impacts food intake, growth and potential markers of gastrointestinal development’ Animal Feed Science and Technology 209 (2015) 268-273.

E. Eckert, H.E. Brown, K.E. Leslie, T.J. DeVries and M.A. Steele, ‘Weaning age affects growth, feed intake, gastrointestinal development, and behavior in Holstein calves fed an elevated plane of nutrition during the preweaning stage’ Journal of Dairy Science Vol. 98 No. 9, 2015.

K.M. Wood, S.I. Palmer, M.A. Steele, J.A Metcalf and G.B. Penner, ‘The influence of age and weaning on permeability of the gastrointestinal tract in Holstein bull calves’ Journal of Dairy Science Vol. 98 7226-7237 No. 10, 2015.

Davis CL, Drackley JK. The development, nutrition, and management of the young calf. Ames (IA): Iowa State University Press; 1998.

Terosky TL, Heinrichs AJ, Wilson LL. A comparison of milk protein sources in diets of calves up to eight weeks of age. J Dairy Sci 1997;80:2977–83.