Growth performance of broiler chickens fed diets containing granulated L-methionine compared with DL-methionine.

A novel granulated L-methionine (Met) has been developed using a simplified purification process, however its replacement with DL-Met has not yet been explored. The objective of the present study was to investigate the growth performance of broilers fed diets containing granulated L-Met (90% purity) compared to a diet containing DL-Met (99% purity). A total of 192 one-day-old broilers were allocated in four dietary treatments with six replicates (eight birds/cage) in a randomized complete block design based on body weight as the blocking factor. Twelve experimental diets were used, with four for each of the three growth stages: pre-starter (day 0 to 7), starter (day 7 to 21), and grower (day 21 to 28). The experimental diets consisted of: (1) a diet containing DL-Met at 100% of the digestible Met requirement, (2) a diet containing granulated L-Met at 85% of the digestible Met requirement, (3) a diet containing granulated L-Met at 90% of the digestible Met requirement, and (4) a diet containing granulated L-Met at the same inclusion rate (approximately 95% of the digestible Met requirement) as diet 1. The broilers were fed experimental diets during the pre-starter, starter, and grower stages, and growth performance was recorded by correcting mortality throughout the experiment period. Over the entire 28-day period, body weight gain and feed intake of broilers fed diets containing granulated L-Met increased linearly (