Milking it for all its worth.

According to Dairy Australia, the Australian dairy industry looks to be in a good place with world prices reaching record levels. Yet at the farm level, dairy farmers are toughing it out with ongoing droughts and the ever rising cost of feeds.

Perhaps a ray of hope is shining from the field of epigenetics and metabolic imprinting with promising outcomes to increase the lactation efficiency of dairy cows.

The process involves manipulation of gene expression regulating mammary gland development and lactation via control of environmental factors, more specifically, via a nutrition regimen of dietary energy restrictions and re-feed phases. Subsequently, by means of metabolic imprinting, the cell’s biological memory is used to pass altered expressions to daughter cells through mitotic cell division, thus maintaining permanence of the desired expression.

The nutrition regimen aims to exploit the compensatory growth phenomenon. This entails rapid weight gain and more importantly, mammary development and thus improved lactation performance of an animal following a period of nutrient deficiency, when place back on a high quality diet. To further concentrate on mammary gland development, energy restrictions are carried out during mid-gestation of a dairy heifer, where the peak of mammogenesis takes place.

The result of compensatory mammary growth is an increase in the potential and longevity of lactation. More significantly, the permanence of this enhancement can be achieved when the manipulated gene expression responsible for increase mammary cell proliferation is stabilised by metabolic imprinting.

Thus applying epigenetics and metabolic imprinting into the production level of the dairy industry could give a much appreciated boost to the weary farmers. Increased lactation efficiency provides positive economic profits, without a need for increasing feed for a greater number of cows to feed, or the need for increased land.

Lucia Yu

Primary source:
Chung, S.P., 2005, 'Role of compensatory mammary growth in epigenetic control of gene expression', The FASEB Journal, vol. 3, pp. 1586-1591.