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UDC 636.5.083.14

Received: April 27, 2026

Revised: May 4, 2026

Published: May 29, 2026

This is an Open Access article under the CC BY-NC-ND 4.0 license

 

The study was conducted at the experimental farm “Preservation of the State Poultry Gene Pool” of the Department of Animal Husbandry and Veterinary Sciences of the NAAS using male chickens of the meat-egg population “Hercules White” of the combined type of productivity. The effect of diets with different levels of crude protein on production indicators, slaughter characteristics and chemical composition was determined. meat of male chickens of the combined direction of productivity of Ukrainian selection. 180 day-old male chickens were divided into 3 groups, which were subsequently grown under similar technological parameters in separate isolated sections and fed with diets with different levels of crude protein in the starting, growth and finishing periods: 1st group – 23%, 21% and 19%; 2nd group – 21.5%, 19% and 17%; 3rd group – 20%, 17% and 15%. The content of metabolizable energy 300 kcal/100 g, 310 kcal/100 g, 320 kcal/100 g and other nutrients in the diets of cockerels of the same age was the same. According to the results of growing The advantage of male birds of the 1st experimental group in terms of live weight compared to other groups persisted until 10 weeks of age. At 8 weeks of age, it was statistically significant ( P <0.05) only between chickens of groups 1 and 2. At 12 and 14 weeks of age, the cockerels of group 3 had the largest live weight, although the difference was insignificant and statistically insignificant. According to the data of slaughter at the age of 14 weeks 90.39% – 89.98%. The slaughter yield of semi-gutted carcasses was higher than that at the fattening period of 8 weeks, by 3.96-3.74%. Analysis of the chemical composition of the meat of male birds of the experimental groups showed that with age the moisture content of the pectoral muscles in the 3rd group decreased compared to the first, it was lower by 0.4% at 14 weeks, but the crude protein content increased by 1.1% compared to 8 weeks. The crude lipid content in the thigh muscles was higher than in the pectoral muscles by 1.9-2.0 times. The pH of the thigh muscles was higher than the pH of the pectoral muscles by 3.7-6.0%. No significant differences were found for any sensory parameter. The feed conversion ratio during the entire period of cockerel rearing was numerically better in group 1 and the worst in group 3. However, if after 8 weeks of rearing the difference in this indicator between these groups was 9.9%, then it decreased and at 14 weeks of age was only 3.5%. Feed consumption per 1 kg of live weight gain in the second group was higher compared to group 1 by 2.3%, in group 3 it was higher compared to group 1 by 3.5%, and compared to group 2 by 1.1%. At the same time, the cost of feed consumed per 1 kg of live weight gain in the 2nd group was lower compared to the first group by 9.86%, in the 3rd group it was lower compared to the 1st group by 22.18% and by 13.64% compared to the 2nd group, which indicates the economic feasibility of fattening cockerels on low-protein diets.

 

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