AUTHOR=Adhikari Pratima Acharya , Castro Fernanda Lima de Souza , Liu Guanchen , Kim Woo Kyun 

TITLE=Effects of Total Sulfur Amino Acids on Growth Performance, Immunity, and Meat Yield in Broilers Fed Diets With and Without Antibiotics

JOURNAL=Frontiers in Veterinary Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.903901

DOI=10.3389/fvets.2022.903901

ISSN=2297-1769

ABSTRACT=Two experiments were conducted to evaluate effects of sulfur amino acids (SAA) on performance, carcass yield, immunity, and amino acid transporters in broilers fed diets with/without an antibiotic growth promoter (AGP). In Experiment 1, a total of 250 one-day old Cobb500 male chicks were assigned to battery cages with two levels of AGP (0 and 0.05% Bacitracin) and five levels of SAA (0.7, 0.8, 0.9, 1.0 and 1.1%) for 21d. In Experiment 2, a total of 900 one-day old chicks were assigned to floor pens with two levels of AGP and three levels of SAA for starter (0.7, 0.8 and 0.9%) or finisher phase (0.52, 0.62 and 0.72%) for 42d. In experiment 1, from 0-7d, the body weight gain (BWG) was the lowest for birds fed 0.7% SAA. AGP significantly decreased the feed conversion ratio (FCR), and birds fed 0.9 and 1.1% SAA had significantly lower FCR than 0.7% SAA. From 8-14d, for AGP fed birds, the lowest BWG was observed in 0.7% SAA group. In birds not fed AGP, birds fed 0.8% SAA had higher BWG than 0.7 and 1.1% SAA. Birds fed 0.7% SAA diet had lower feed intake (FI) than 0.8% SAA and higher FCR than 0.8, 0.9, and 1.0% SAA. In experiment 2, from 0-21d, the lowest BWG and highest FCR were observed in birds fed 0.7% SAA, whereas birds fed 0.9% SAA had highest BWG and lowest FCR. From 22-42d, FCR was lower for birds fed AGP, and for birds fed 0.72%. Interactions between the factors were found for FI and BWG. The whole thigh and wing weights were the highest for 0.62% SAA, and the Pectoralis Major weight was higher for birds fed 0.62% SAA than those fed 0.52% SAA. There was an interaction between SAA and AGP for Lat1 (large neutral amino acid transporter), and AGP fed birds had higher expression of interleukin 1β (Il-1β). Interleukin 10 (Il-10) was upregulated in the ileum. There was an interaction between the factors for sodium-dependent neutral amino acid transporter B(0)AT1 (SLC6A19) expression. The results suggested that AGP and SAA supplementation would affect growth performance of broilers.