Some parameters of egg quality in hens selected for lower content of yolk cholesterol

We evaluated the basic parameters of variability of weight and quality parameters in eggs, as content of cholesterol in yolk and edible part of egg of father and mother lines (FL and ML) selected for decreased concentration of yolk cholesterol, and t-test of significance of differences between the father and mother lines. Weight of eggs, egg white and egg shell in the tested hens of father line were significantly higher than in hens of mother line. There were no significant differences between the lines in weight of yolk and edible part. The weight of egg was 61.84 g in FL and 59.41 g in ML, weight of yolk was 15.86 g and 15.64 g, weight of white 38.84 and 37.15 g, and weight of shell 7.16 and 6.59 g, respectively. The edible part created 54.68 g in FL and 52.80 g in ML. The portion of yolk out of the weight of egg was 26.30 and 25.69%, index of egg shape 76.98 and 75.31%, concentration of cholesterol in mg/100 g yolk 1543.2 and 1511.2, and concentration of cholesterol in mg/100 g edible part 448.2 and 449 g, respectively. Significant differences between lines were in the index of egg shape only, the value being higher in FL, i.e. the eggs were more round. The individuality of layer has significant to very highly significant effect on the studied parameters of egg quality in the father as well as mother lines. The concentration of yolk cholesterol correlated markedly negatively with the weight of yolk, and significantly positively with the index of egg shape and concentration of cholesterol in the edible part. The egg weight correlated significantly positively with all other partial weight parameters of egg, i.e. with weight of yolk, white, shell and edible part of egg, and significantly negatively with the concentration of cholesterol in edible part and with the portion of yolk out of the egg weight. The weight of yolk correlated significantly and positively with the weight of white and shell, with edible portion of egg and with portion of yolk. The weight of white corellated significantly positively with shell weight, and significantly negatively with the concentration of cholesterol in edible part and portion of yolk. The weight of edible part correlated significantly negatively with the conccentration of cholesterol in edible part. The concentration of cholesterol in edible part correlated significantly positively with the portion of yolk in the weight of egg