Application of the system for the net utilization of energy and protein through the „Clarcs“ indices in dairy cattle breeding

A methodology for calculating the net utilization of energy and protein along the feed-cow’s milk chain by using the Clarc energy distribution (CED) and Clarc protein transformation (CPT) criteria was adapted. Data from experiment with elite cows of the Bulgarian Black-and White cattle breed during the first 100 days of lactation were used as a basis. The obtained CED (average 0.5766 with periodic variations between 0.5275 and 0.6178) and CPT (average 0.9104 with periodic variations between 0.8324 and 0.9984) reflect the highest transformations of net energy and protein digestible in the intestine from forage into gross energy and crude protein of direct consumed from human product, compared to other domestic animal products.