An Investigation on the Effects of Partial Replacement of Rapeseed Cake in Ayrshire Dairy Heifers' Diets with By-Product Source of Animal Protein on Body Weight Dynamics, Nutrient Balancing, and Blood Biochemical Markers.

Recently, the secondary use of by-products of the processing industry resulting from the production of poultry meat, which can be included in animal diets, has become a popular topic in the feed industry. For studying the effects of partial replacement of rapeseed cake (RC) with the by-product source of animal protein concentrate Agro-Matic (PCAM) on growth dynamics, nutrient absorption and nitrogen balance, as well as blood biochemical parameters during the growing period, a total of 48 Russian Ayrshire dairy heifers were selected for this experiment and they were divided into three experimental groups (16 in each group, including the control group). The heifers of the control group were fed the basal diet which contained rapeseed cake (30%), while the second (RC + PCAM) and third groups (PCAM + RC) were fed the basal diet after replacing a part of the rapeseed cake with 2.