EFFECT OF ENVIRONMENTAL-TEMPERATURE, SEX AND FATTENING PERIOD ON AMINO-ACID-COMPOSITION OF BREAST MEAT OF BROILERS

In one experiment using 1600 birds, the effect of high constant temperature 30-32-degrees-C versus control as well as the effect of sex and fattening period (up to 12 weeks) on the amino acid composition in small breast meat was examined. Light effect on the amino acids glyzin and prolin was found, the control birds had higher values. The males showed higher values for non-essential and some essential amino acids in the breast meat. The biological protein index was 0.63 both in males and females. The prolongation of the fattening period changed the amino acid pattern. The values of the essential amino acids, especially of isoleucine, leucine, lysine and valine, increased to an age of 8 weeks and decreased after that age to the end of the fattening period. The values of the non-essential amino acids, but not of alanine and histidine, increased at the age of 5 weeks and decreased in the 6th week. In the last fattening period the values increased again. The biological protein index was 0.06-0.65 and lower in the last fattening period.