The Effect of Methionine or Methionine Hydroxy Analogue Supplementation on Chick Response to Total Sulfur Amino Acid Intake

Abstract

The results of four battery trials were used to compare the relative effectiveness of dl-methionine (DLM) and dl-methionine hydroxy analogue (M-analog) as supplements to soybean meal diets fed to broiler strain chicks. A total of 108 observations of 28-day body weight and corresponding total sulfur amino acid (TSAA) consumption were divided equally to form regression models based on TSAA intake containing either DLM or molecular equivalent amount of M-analog. At maximum effective TSAA intake, the predicted chick body weight resulting from DLM supplementation was 695 grams as compared to 693 from M-analog supplementation. At mean TSAA intake, predicted chick weights were 651 and 650 grams resulting from DLM, and M-analog supplementation, respectively. The pooled mean weight of unsupplemented controls was 584 grams. At low levels of supplementation, the linear change in weight per gram TSAA consumed was predicted to be 77.2 grams with DLM and 76.6 grams with M-analog.