The effect of Zinc and Copper proteinate on the hematological parameters of growing pigs and the digestibility of nutrients in compound feed

The article presents the results of a scientific and economic study on the effects of different levels of zinc and copper proteinate in the diets of four-breed hybrid piglets during fattening on hematological parameters and feed nutrient digestibility coefficients. The study confirms the importance of balanced feeding for achieving high productivity in hybrid pigs, particularly in ensuring their bodies receive essential trace elements such as zinc and copper. These elements play a key role in enzymatic activity, metabolism, and immune system function. The use of organic trace elements promotes better absorption and bioavailability compared to inorganic salts, such as sulfates. Feeding zinc and copper proteinates improved metabolic processes in the body without negatively affecting biochemical and morphological blood parameters. Hemoglobin levels in pigs of the 3rd experimental group exceeded the control by 6.1 % (P ≤ 0.001), while in the 2nd, 4th, and 5th groups, they were higher by 1.7 %, 4.6 %, and 3.1 %, respectively. The total protein concentration in the blood serum of pigs in the 3rd group was higher by 9.3 % (P ≤ 0.001), in the 4th group by 8.8 % (P ≤ 0.001), and in the 5th group by 7.1 % (P ≤ 0.001) compared to the control. Regarding trace element levels, zinc concentration in the experimental groups was higher than in the control by 8.9 % (P ≤ 0.001), 17.8 % (P ≤ 0.001), 12.5 % (P ≤ 0.001), and 2.3 %, respectively, while copper concentration was higher by 6.6 %, 20.0 %, and 13.3 % in the 2nd, 3rd, and 4th groups, respectively. The inclusion of zinc and copper proteinates in the diet enhanced nutrient digestibility. The highest values were observed in pigs of the 3rd group when zinc proteinate was added at 332.9 g/t and copper proteinate at 10.9 g/t of compound feed. The overall digestibility of organic matter in the experimental groups ranged from 81.6 % to 85.6 %. The digestibility coefficients in the 2nd, 3rd, 4th, and 5th groups exceeded the control by 1.6%, 4.0 % (P ≤ 0.05), 3.2 % (P ≤ 0.05), and 3.0 % (P ≤ 0.05), respectively. The digestibility of crude protein in the experimental groups was higher than in the control by 0.6 %, 3.5 % (P ≤ 0.05), 2.4 % (P ≤ 0.05), and 1.3 % (P ≤ 0.05), while crude fat digestibility increased by 0.5 %, 2.6 % (P ≤ 0.05), 1.5 %, and 0.6 %, respectively. The digestibility of crude fiber in the 3rd group exceeded the control by 2.7 % (P ≤ 0.01), in the 4th group by 2.2 % (P ≤ 0.05), and in the 5th group by 1.4 % (P ≤ 0.05). The digestibility coefficients of nitrogen-free extractives in the 2nd, 3rd, 4th, and 5th groups were higher than in the control by 4.2 %, 6.1 % (P ≤ 0.05), 5.1% (P ≤ 0.05), and 4.5 %, respectively.