The aim of this research is to compare the carcass composition and meat quality characteristics of spent Cobb 500 and Ross 308 broiler breeders. A total of 28 carcasses were evaluated—7 female and 7 male carcasses from each genotype. Dissection was performed, and the percentages of neck, wings, skin with subcutaneous fat, abdominal fat, residual components, breast and leg muscles were calculated relative to the eviscerated carcass weight. The breast and leg muscles were evaluated for their chemical composition, color attributes (Lab), acidity (pH₂₄), and electrical conductivity (EC₂₄). Analysis of the structure and texture of the pectoralis major muscle was performed. The genotype of the birds had an impact on the eviscerated carcass weight, percentage of skin with subcutaneous fat, leg muscles, wings, and neck. Broiler breeder genotypes differed in terms of the chemical composition of the breast and leg muscles, except for the water content in the breast muscle and the collagen content in both the breast and leg muscles. The breast muscles of Cobb 500 exhibited lower cooking loss, pH₂₄, redness, and yellowness, while the leg muscles of Ross 308 had lower EC₂₄ but higher cooking loss and lightness values. The pectoralis major muscle of Cobb 500 was firmer and more tender, with a smaller cross-sectional area of the muscle fiber and a smaller vertical (V) diameter of the muscle fiber. Males were characterized by a greater carcass weight and a higher percentage of leg muscles, neck, and carcass remains. On the other hand, females had a higher percentage of breast muscles, skin with subcutaneous fat, and abdominal fat. The sex of the birds affected the chemical composition of the breast and leg muscles, with the exception of the water content in the breast muscles and collagen content in the breast and leg muscles. The breast muscles of females were characterized by higher values of yellowness, although they also exhibited lower pH and cooking loss. In terms of texture analysis of the pectoralis major muscle, the meat of females was characterized by higher tenderness and firmness. However, the analysis of the structure showed that males had a thicker perimysium and endomysium. Regardless of broiler origin and sex, significant differences were found between the breast and leg muscles in terms of the assessed physicochemical features (pH₂₄, EC₂₄, cooking loss), color attributes (Lab) and chemical composition (protein, intramuscular fat, and collagen contents). Genotype and sex interactions were significant for the chemical composition of the breast muscles (protein, fat, collagen) and leg muscles (fat), as well as for the yellow color saturation of the breast muscles and springiness of the pectoralis major muscle. The study produced results that showed the meat and carcasses of spent hens and roosters to be suitable for processing due to their favorable chemical composition, high nutritional value and good technological properties, as assessed based on the results of meat texture and structure.

The aim of the study was to determine the effects of genotype and sex on carcass composition and selected meat quality parameters of Dworka and Pekin ducks after two reproductive seasons. The research material consisted of 24 carcasses of Dworka ducks (breeding strain D11) and 24 carcasses of Pekin ducks from the herd of genetic resources (French Pekin, strain P-9). After cooling the carcasses (18 h, 2 °C), the pH values and electrical conductivity of the pectoral and leg muscles were determined, and then the carcass was dissected using a simplified method. After dissection, the pectoral and leg muscles were sampled for quality characteristics assessment. The Dworka ducks from breeding strain D11 compared to Pekin duck from conservative strain P9 were characterized by significantly (p < 0.05) higher carcass weight, protein and salt content, thermal drip, yellowness, thickness of perymisium and endomysium and lower water content of the pectoral muscle. Dworka ducks were also characterized by higher protein, salt and collagen content and higher electrical conductivity (EC₂₄) of leg muscles than Pekin ducks. Regardless of genotype, male ducks had a higher gutted carcass weight with neck, salt content, muscle fiber cross-sectional area, fiber perimeter and diameters of pectoral muscle, and also higher protein and collagen, and lower fat content, pH₂₄ and electrical conductivity of leg muscles. The genotype by sex interaction was significant (p < 0.05) for water, protein, fat content, perimisium thickness, cohesiveness, springiness of the pectoral major muscle, and for water content and protein of the leg muscles. The results obtained in this study demonstrate the effects of genotype and sex on the nutritional value and some technological parameters of duck meat. The studied ducks after two reproductive seasons satisfactorily meet the requirements of duck meat for consumers and duck meat processing plants.

The purpose of the study was to compare young (6-wk-old) and spent (52-wk-old) Japanese quail in terms of body weight, carcass characteristics, and some meat quality traits. Whole carcasses were dissected, pectoral muscles and leg muscles were sampled for determination of basic chemical composition and L*a*b* color parameters, while m. pectoralis major was sampled for texture and microstructure traits. Age of quails had a significant effect on body weight, carcass weight, carcass yield, pectoral muscle, abdominal fat and skin with subcutaneous fat, and carcass remainders contents in eviscerated carcass. Spent quails had significantly higher intramuscular fat content in pectoral and leg muscles and protein content in breast muscle, and also lower content of water in breast and leg muscles than young quails. Slaughter age significantly affected lightness (L*) and redness (a*) of pectoral muscles, as well as texture traits (except for cohesiveness) and microstructure of m. pectoralis major, except for thickness of perimysium and endomysium. Regardless of age, quail sex had an effect on the carcass traits studied (except for leg muscle content), intramuscular fat content of pectoral and leg muscles, water content of leg muscles and yellowness of pectoral muscle. In addition, a significant effect of quail sex was found on cutting work, springiness, chewiness and marked microstructural characteristics, except for vertical fiber diameter. The interaction between age and sex was significant for most slaughter and microstructural characteristics and also WB-shear force of m. pectoralis major, and L*, b* pectoral muscles. Higher fatness of carcasses, higher intramuscular fat in meat, and poorer textural and microstructural characteristics of m. pectoralis major spent Japanese quail indicate poorer fulfillment of most consumers' requirements compared to carcasses and meat of young quails.

The aim of this study was to determine the effects of slaughter age and sex on the carcass characteristics, meat quality parameters, and leg bone dimensions of common pheasants. The study material consisted of 40 common pheasants, including 10 males and 10 females at 12 weeks of age and 10 males and 10 females at 15 weeks of age. The birds were kept on a farm in a semi-intensive system. The slaughter age had significant effects on the eviscerated carcass weight; the percentage of skin with subcutaneous fat; the wings percentage; electrical conductivity (EC₂₄); the work required to cut the samples (cutting work); redness (a*); the intramuscular fat content in the breast meat; and the protein, intramuscular fat, water, and collagen contents in the leg meat. The sex of the pheasants had significant effects on the eviscerated carcass weight; the contents of leg muscles, skin with subcutaneous fat, and wings in the carcasses; and the electrical conductivity, thermal loss, lightness (L*), and redness (a*) of the breast muscles. It also significantly affected the protein and water contents of the pectoral and leg muscles, the intramuscular fat contents of the leg muscles, the texture traits of the pectoralis major muscle, and all femur and tibia bone dimensions. The results indicate a greater influence of sex compared to slaughter age on the pheasant traits studied. We confirmed the occurrence of a clearly marked sexual dimorphism in birds of this species. Both factors (slaughter age and gender) have significant effects on the nutritional and technological value of pheasant meat. The few studies on meat texture and the dimensions of pheasant leg bones indicate a need for continued research in this area in the future.

The aim of this study was to compare the quality characteristics of the meat of two genotypes (Lohmann Brown and Lohmann White) of laying hens after the laying period. Studies were conducted on pectoral and leg muscles from 26 females, 13 of each genotype. Breast and leg muscles were evaluated in terms of their basic chemical composition, acidity (pH₂₄), color attributes (L*, a*, b*), electrical conductivity (EC₂₄) and macro- (K, P, Na, Mg, Ca) and microelements (Fe, Zn, Cu, Mn, Cr). Analysis of the texture of the pectoral muscle major and rheological properties (sum of viscosity modules and sum of elasticity modules) was also performed. Breast and leg meat were also subjected to sensory evaluation. The genotype of the birds significantly affected the percentage of intramuscular fat in the pectoral muscle and the percentage of protein, fat and water in the leg muscle. When analyzing pectoral and leg muscles for color attributes, we found no significant (p > 0.05) differences between genotypes. Differences were shown, however, between genotypes in EC₂₄ and phosphorus content in leg muscle. Breast muscles differed significantly (p < 0.05) in iron and zinc content. Sensory analysis revealed significant differences between genotypes in leg muscle tenderness and juiciness, and breast muscle juiciness and aroma desirability. When analyzing the breast muscle in terms of texture, we did not observe any significant differences, nor did we find any differences in the assessment of rheological properties. Not depending on genotype, however, we noted significant differences between protein, fat, water and collagen content, sodium, magnesium, calcium, iron, zinc, copper, manganese, chromium, acidity, color parameters (L*, a*, b*), EC₂₄ and tastiness desirability between breast meat and leg meat. The results of this study showed that meat from old hens obtained after the laying period is a good material for further technological processing, due to its favorable basic chemical composition and high nutritional value expressed in the content of macro- and microelements, and is also characterized by relatively good sensory characteristics, which can be improved by marinating or adding enzymatic preparations during its processing.

This research aimed to determine the effect of intramuscular fat (IMF) levels in m. pectoralis major on carcass weight and composition, meat of male broiler chickens. Whole eviscerated necked carcasses of Ross 308 male broiler chickens aged 42 days were purchased from a commercial poultry slaughterhouse. After the carcasses were dissected, m. pectoralis major was sampled to determine their basic chemical composition, physicochemical and sensory characteristics, texture, and microstructural characteristics. The IMF content of the m. pectoralis major evaluated male Ross 308 broiler chickens at 42 days of age ranged from 0.88 % to 4.64 %. The majority (about 66 %) carcasses contained pectoral muscle containing no more than 2.04 % IMF. Male broiler chicken carcasses differed (P < 0.05) in IMF, water, and protein content of m. pectoralis major. Breast muscles of Ross 308 chickens with the highest IMF levels (2.05-4.64 %) had significantly less water and protein compared to those of chickens with the lowest (0.88-1.60 %) and medium (1.61-2.04 %) IMF levels. IMF level had no effect on carcass weight and composition, physicochemical characteristics, texture, and microstructure of m. pectoralis major. To date, there have been no studies determining the effect of IMF level on microstructure and texture traits of m. pectoralis major (except WB shear force) and electrical conductivity in Ross 308 broiler chickens. The results obtained indicate the need for future research in this area with consideration of males and females and research material from multiple sources.