Meeting Energy Demands in the First Week of Life – Dr. Noah Litherland, Vita Plus

By Dr. Noah Litherland, Vita Plus dairy youngstock technical specialist
When walking through calf barns and hutches during the winter, it is somewhat difficult to differentiate sickness behavior from cold stress behavior.  Interestingly, calf behaviors are quite similar when they are struggling with a disease challenge and when they are battling cold weather.  In young calves, both stressors decrease activity and reduce thriftiness of appearance.

Negative energy balance is a well-known occurrence in transition cows, but rarely discussed in the calf world.  The severity and duration of negative energy balance can have impacts on the growth and health of calves during the first weeks of life.  Energy, behind water, is the second most important nutrient for life.  Interestingly, calves often lose bodyweight from birth through the first week of life.  Loss of bodyweight is an indication that maintenance requirements are not being met and calves are surrendering body mass to their environment.

Last winter – one of the coldest winters on record – a comparison study conducted at the University of Minnesota demonstrated that calves fed an increased plane of nutrition not only maintained their bodyweight, but also had increased rates of growth during the first week of life.

Managing for energy balance
What is the cost of no growth or, worse yet, a loss in bodyweight during the first week of life?

Perhaps a good goal for newborn calf performance during the first week of life should be to maintain or even begin gaining bodyweight.  Practically, producers should consider weighing a subset of calves at birth and again at one week of age to determine change in calf weight.  This measure might be a strong indicator of the success of the calf nutrition and management program.

Factors, such as pathogen challenge, can also increase energy associated with immune function activity and decreased efficiency of nutrient absorption if the pathogen damages the lining of the small intestine.

When I previously worked in research at the University of Minnesota, we collected samples from cows during the first week of lactation for milk composition evaluation (Table 1).

The composition of first week milk clearly shows some differences in composition compared to whole milk with higher protein, fat, and total solids, but lower lactose content.  Perhaps during the first week of life, calves would benefit from higher milk fat content to reduce the risk of negative energy balance on growth and health.  In addition, the cornerstones of optimal calf care – including deep bedding, calf jackets, and a clean, draft-free environment – play a major role in calf health and performance from day one.

Table 1. Milk composition of week one test of multiparous dairy cows (N = 160).

	Whole milk	Week 1 milk	Week 1 solids	Standard deviation
Milk protein (%)	3.0	3.7	27.1	0.7
Milk fat (%)	3.7	4.3	31.4	4.3
Milk lactose (%)	5.0	4.7	34.3	0.2
Milk total solids (%)	12.7	13.7	—	2.3

This article was originally written for the January 19, 2015 issue of Progressive Dairyman and titled “How important is calf energy balance during the first week?”