Ration-balancing protein supplement

Most of the models used to balance dairy rations consider protein and energy as two separate entities. Despite this dichotomy that we have imposed on the predictive models, cross-reactions between energy and protein supply and the mUk component responses occur. One of the simplest examples is the response of mUk and lactose yields to protein supplementation, in addition to the protein response. Using from the database of Doepel et al. (2004) only the studies where casein, casein hydrolysates or amino acids (AA) with a casein profile had been infused, the response (g/g) of lactose yield to the increased protein supply is almost identical to the response of protein yield (Figure 1). 

The term "ration-balancing protein supplement" refers to milk products as defined by the American Association of Feed Control Officials and includes such materials as dried buttermilk, dried skim milk, dried whole whey, casein and cheese rind. It also includes yeast (as that term is defined by said Association) and hence refers to such materials as distiller s dried yeast and torula dried yeast. 

---