Elevated planes of energized calf milk resulted in higher growth, a reduction of age at first insemination and a higher conception rate

The quality of early life nutrition in dairy calves has a big impact on pre-weaning daily gain[1,2,3,4,5,6,7,8,9,10]. Increased pre-weaning growth as a result of pre-weaning feeding schedules with elevated planes of nutrition result in an improved fertility[5,9,10], which is one of the reasons that these schedules result in an increase in average life-time daily gain.

Fat levels in traditional calf milk replacers can be significantly lower than those of whole milk. Energized calf milk replacer with a composition close to that of whole milk was compared to a traditional calf milk replacer[11].

Key takeways from the research

  • A LifeStart feeding schedule with energized calf milk containing 25% fat increased pre-weaning average daily gain by 103 g/day

  • Calves in the LifeStart group had a lower age at first insemination and a higher conception rate

Study design

A group of 60 calves was fed energized calf milk (ECM) with 25% crude fat from birth until they were weaned at 63 days of age. The amount of energized calf milk replacer fed over the entire period of 63 days was 43.6 kg. A control group was fed a traditional calf milk replacer with 18% crude fat and a total amount of 34.1 kg and also weaned at 63 days of age. Both groups had ad libitum access to starter feed. Calves were weighed at 63 days and 91 days of age and intake of starter feed and fertility parameters were recorded.


Average daily gain between birth and day 63 in the ECM group was 673 g/day vs. 567 g/day for the control group. Between birth and day 91, ADG in the ECM group was 854 g/day vs. 764 g/day for the control group. Starter intake was not different between the 2 groups with an intake of 20.6 kg for the ECM group vs. 19.6 kg for the controls.

The age at 1st insemination went down from 13.7 months for the controls to 12.4 months for the ECM group, with a conception rate at 1st insemination of 73.4% for the ECM group vs. 62.0% for the controls.

Feeding energized calf milk improved growth and fertility


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