Application of a mechanistic model of bovine milk protein synthesis to examine the use of isotope labeling methods

Effect of feeding pattern and behaviour on hormonal changes and milk composition

There is no doubt that feeding and nutrient availability modify the metabolism through hormonal changes. It is otherwise interesting to better define the influence of the imposed or freely chosen meal distribution during the day; in fact the daily feed intake in a relatively short time, namely during the daylight, seems to induce a clear anabolic phase in afternoon-night (high insulin and low urea) and a catabolic one in the morning (low insulin and high urea); among the possible consequences, the lower fat content in the morning milking and the higher one in the afternoon, are of great importance. The factors that can influence these daily changes are many, namely the meal size, the day or night, the stage of lactation and perhaps a genetic effect. These results can be useful for a better interpretation of blood parameters and of the relationships between feeding and milk composition.