This research aimed to observe the interaction of methionine-cysteine amino acid supplementation to decrease the effect of aflatoxin B1 (AFB1) on diet against production performance of broiler chicken. A number of 240 mixed sex broiler chickens were treated in 9 treatments by factorial design 3 x 3 with methionine-cysteine amino acid (M+C) (75,100, dan 125%) factors and AFB1 levels (0, 200, dan 400 ppb). Variables observed were: Weight gain, feed consumption, and feed conversion ratio (FCR). The results showed that increased AFB1 content in diet from 0 to 400 ppb increased chicken body weight (P <0.05) in each age group. The high body weight was balanced with high feed consumption along with increased nutrient needs, mainly sulfuric amino acid (M+C) as the precursor of glutathione to eliminate toxic through conjugation reactions. The interaction effect was firstly occurred between M + C and AFB1 treatment (P <0.05). Meanwhile increased supplementation of M + C from 75 to 125% caused decreased feed consumption in each age group of chickens, but increased AFB1 levels further increased feed consumption (P<0.05). The interaction effect between the level of M + C and AFB1 contamination in diets on feed consumption were seen in 21-day-old chickens (P<0.05). FCR was also increased (P <0.05) with the reduction of M + C content in diet at 7 days old. The effect of AFB1 on diet and interaction between M + C and AFB1 on chicken FCR in this study was not significant in all age groups. It can be concluded from the current study that supplying methionine-cystine amino acid with 75, 100 and 125% in AFB1 contaminated diet of 0, 200 and 400 ppb improves the performance of broiler chicken production.
An active serine is involved in covalent substrate amino acid binding at each reaction center of gramicidin S synthetase.
