While it’s important to understand the data that supports the LifeStart program, one formula is easy to remember: 1 equals 4. In other words, every extra gram gained by a calf prior to weaning translates to 4 additional litres of milk during the first lactation.
1 = 4… here’s why
When approaching the LifeStart program for the first time, the best place to start is its effect on milk production. The 4 litres of milk produced for every gram of growth is the result of a careful analysis of performance data correlating average daily gain and the volume of milk at first lactation. The data studied, as well as subsequent trials, have yielded results ranging from negative impact to up to 13 litres per gram of ADG. From here, a conservative goal of 4 litres of additional milk has been set, with higher volumes achievable in many cases. The table below shows the datasets examined with lactation volume as a function of ADG and weight at weaning. The mission of LifeStart is to give farmers and their advisors the means to meet and exceed these performance levels through careful application of LifeStart.
If “1 = 4” describes LifeStart targeted performance, understanding why “1 = 4” is an important step in evaluating LifeStart’s effectiveness. This begins by understanding two key notions closely associated with LifeStart: “Metabolic programming” and “Epigenetics.”
Metabolic programing is a natural phenomenon that determines how an organism reacts to a given level of nutritional stress or stimulus. The way the organism adapts can permanently change the physiology and metabolism of the organism and continue to be expressed in the absence of the stimulus/stress (Patel and Svrinivansan, 2002). Indeed, these “epigentic” adaptations can even be passed from one generation to the next. Metabolic programming can be observed in many species, including humans.
The notion of “Epigentic” describes changes in gene expression that are independent of changes in the DNA sequence. The definition of epigenetics includes the ability to transfer such patterns of gene expression to the next generation through the inheritance of gene expression rather than gene sequence (Bartol et al. 2008).
If the gene sequence determines the “potential” of the organism, the epigentic level acts as the switches that activate, or attenuate, the genes.
Calf nutrition: a critical enabler
For calves, the critical enabler of positive metabolic programming is the attainment of a high plane of nutrition in the first 8 weeks of life. Calves that achieve this level grow more rapidly than their limit fed counterparts and have higher weights at weaning (see chart). This is important for two reasons. Because calving is a function of body weight and stature rather than age, faster growth will have a favorable impact on the moment of first calving, with obvious advantages in terms of lifetime productivity. Secondly, cows that grow faster show tissue development differences. This applies to the mammary gland as well as to all organs. The enhanced development of the mammary, notably that of the mammary parenchyma, the gland’s productive tissue, is a byproduct of early and rapid growth and plays an active role in enhanced milk production in cows that have been optimally nourished in the first eight weeks of life (Brown et al. 2004).
The search for biological markers
There is still much to be discovered about the phenomenon of metabolic programming. Towards this end, Trouw Nutrition and LifeStart are sponsoring long-term trials of which one of the goals is to determine the biological markers that will allow further optimisation of the process of metabolic processing.