All calves need to get colostrum: it’s definitely the best meal of their lives! However, after that, most calves are separated from their mothers within 24 hours and may be reared in small groups together. The question is: does this affect their growth performance or behaviour?

Effects on Growth

• If calves are left to suckle their mothers, the cow produces up to 14kg LESS milk per day to weaning. This is economically unsustainable in most dairies!
• Calves staying with their mothers for up to 6 weeks, gained weight at 3 times the rate of separated calves up to 6 weeks (Roth B.A. 2009)
• Calves on automatic feeders gain more weight than suckled calves after weaning (0.4kg/d) (Roth B.A. 2009)
• Calves on automatic feeders eat 16-19kg more concentrates in total to weaning than suckled calves (Roth B.A. 2009). This however, is far less money invested than that lost in milk from mothers.
• Calves kept with their mothers gain 25-28kg more than automatic-fed calves to weaning (Roth B.A. 2009) (Kisak P. 2011)
• There is no evidence of any difference between group or individually housed calves or separated/suckled calves on disease rates (Costa J.H.C. 2016) (Grondahl A.M. 2007) (Kisak P. 2011) (Lee H.J. 2009)

Effects on Behaviour

Behaviour of mothers and calves is more subjective to measure and evidence reflects this. People tend to measure vocalisation of calf and mother, play behaviour, head movements and other signs that they think might be seeking behaviour for either mother or calf.

• The calf to mother bond increases with increasing time to weaning and mothers/calves bond to their specific parents/offspring.
• These bonding behaviours however, appear to be present even after 6 hours from birth in the mother but not so much in the calves (Stehulova I. 2017), so separation from this time onwards would appear to have a behavioural effect on the animals concerned.
• Calves and mothers appear to seek each other, but this behaviour is expressed less with the mother, even after 3 hours of separation.
• Separation appears to have effects on calves but only after several days of contact, so separation early would appear to be beneficial if this is your management strategy

Summary

From an economic point of view, separation at birth has better growth weights in calves after weaning and has lower Johnes’ disease rates (Windsor, 2010). It also gives up to 14kg more milk per day from the mother. This makes separation at birth an essential decision on most dairies. From a behavioural point of view, there are beneficial effects of staying with mothers in terms of bonding but separation at birth does not appear to have effects on the calves and mothers seem to have less impact after even 3 hours of separation.

Where is the Evidence?

• Roth B.A., Barth K., Gygax L., Hillmann E. 2009. “Influence of artificial vs mother-bonded rearing on sucking behaviour, health and weight gain in calves.” Applied Animal Behaviour Science 119: 143-150
• Kisak P., Broucek J., Uhrinkat M., Hanus A. 2011. “Effect of weaning calves from mother at different ages on their growth and milk yield of mothers.” Czech Journal of Animal Science 56 (6): 261-268
• Grondahl A.M., Skancke E.M., Mejdell C.M., Jansen J.H. 2007. “Growth rate, health and welfare in a dairy herd with natural suckling until 6-8 weeks of age: a case report.” Acta Veterinaria Scandinavica 49 (1): 16
• Jensen M.B. 2011. “The early beaviour of cow and calf in an individual calving pen.” Applied Animal Behaviour Science 134 (3-4): 92-99
• Lee H.J., Khan M.A., Lee W.S., Yang S.H., Kim S.B., Kee K.S., Ha J.K., Choi J.K. 2009. “Influence of equalizing the gross composition of milk replacer to that of whole milk on the performance of Holstein calves.” Journal of Animal Science 87 (3): 1129-1137
• Stehulova I., Valnickova B., Sarova R., Spinka M. 2017. “Weaning reactions in beef cattle are adaptively adjusted to the state of the cow and the calf.” Journal of Animal Science 95 (3): 1023-1029

• Windsor P.A., Whittington R.J. 2010. “Evidence for age susceptibility of cattle to Johnes’ Disease.” The Veterinary Journal 184 (1): 37-44