Effect of alanine-producing bacteria on the growth of chicks

The effects of alanine-producing bacteria administered orally on the growth of chicks was investigated. The chicks were given diets containing adequate amounts of only the essential amino acids as sources of nitrogen: a basal diet (BD); a BD plus 40 g of urea per kilogram of diet (UD); a UD with bacteria named AR-8-3; a UD with bacteria named AB-605; and a BD plus 59.4 g and plus 118.7 g of L-alanine per kg of diet, respectively, from Day 8 to Day 15. The growth of chicks fed diets containing urea or alanine was significantly faster than that of the BD controls; no significant difference in growth was detected among the groups given the UD and bacteria. Since viable bacteria could not be detected from the intestinal content or from excreta for both groups given the bacteria, the establishment and achievement of alanine-producing activity by the bacteria in the gastrointestinal tract were considered doubtful. The supplement with 59.4 g of alanine per kg of diet improved the growth rate, but the higher inclusion (118.7 g of alanine per kg of diet) resulted in no further improvement.