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

Abstract

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 2.25% and 4.5% of protein concentrate Agro-Matic respectively. The results showed that the weight of heifers treated with PCAM at 3 months of age exceeded the control by 2.3 kg (p > 0.05) in group 2 by 4.4 kg (p p p p < 0.05). Consequently, replacing the rapeseed cake with the protein concentrate Agro-Matic revealed an improvement in the dynamics of growth, nutrient digestibility and nitrogen balance, and it has an effect on improving some biochemical parameters of the blood.

Keywords

• Russian Ayrshire heifers
• by-products
• protein feeds
• growth dynamics
• nitrogen balance
• biochemical parameters