Influence of partial replacement of some inorganic minerals with glycine complex and vitamin D₃ source on performance, slaughter traits, sensory and physico-chemical characteristics of pheasant muscles (Phasianus colchicus L.) depending on gender

The aim of the study was to determine the effect of these substitutions on body weight and slaughtering performance, post-mortem changes, sensory characteristics and chemical composition of selected muscle groups of male and female pheasants. The tests were carried out on pheasants during 5–16 weeks of rearing in enclosed aviaries. Four groups of 8 females and 8 males were formed, and the experimental factor was the supplementation of calcium, iron, zinc and copper salts with glycinates of these elements. The control group received a feed blend containing 100% of the mineral requirement as salts. In the E-25 group, 25% of the salts were replaced by glycinates, in the E-50 group 50% of the salts were replaced, and in the E-75 group only glycinates comprising 75% of the total mineral content were used and no salts were included, with vitamin D₃ replaced by calcitriol. For the duration of the study, feeding was at will and the birds had free access to water. In addition, pheasants were weighed at the age of 4, 8, 12 and 16 weeks. Daily feed intake was monitored. At the end of the experiment, when all the pheasants were 16 weeks old, they were weighed and decapitated. The breast, thighs and drumsticks and the heart, liver and gizzard were removed from the chilled carcasses. Supplementation of calcium, iron, zinc and copper salts with 50% glycinates in feed mixtures for pheasants over a period of 5–16 weeks resulted in a slight improvement in the slaughter weight of birds and a significant increase in crude ash, calcium and zinc, while at 75% supplementation and when calcitriol was used instead of vitamin D₃, increased phosphorus levels were found in the pheasant muscles analysed. Males had higher body weight, body weight gain, carcass, liver and gizzard weights, and their muscles had more magnesium and potassium and less calcium, sodium and iron than females.