Beta‐hydroxy‐β‐methyl butyrate‐supplemented diet for broiler chickens is more conducive to dietary protein reduction than a leucine‐supplemented diet until 21 days old

Abstract

BACKGROUNDDietary L‐leucine or its metabolite 𝛽‐hydroxy‐𝛽‐methylbutyrate (HMB) has a crucial role in the muscle protein metabolism of broilers during the first few‐week growing period. This study aimed to evaluate the effects of L‐leucine (LLPD) or HMB (HLPD) supplementation in a low‐protein diet (20%, LPD) until 21 days old on performance, carcass weight, muscle yield, and meat quality, as well as intestinal morphometry in broiler chickens.RESULTSFrom d 1 to 42, LPD decreased body weight gain (BWG) and feed intake (FI) and increased feed conversion ratio (FCR) compared to a standard protein diet (22%, SPD). The LLPD and HLPD did not affect FI, but the LLPD decreased the BWG and increased the FCR compared to the SPD. The LPD group had lower body and muscle weights than other groups. Compared to LPD, HLPD increased dressing percentage. The LPD decreased the serum IGF‐1 content compared to the SPD and LLPD. The duodenal villus height of the LPD and LLPD broilers was smaller than those of the SPD and HLPD birds. The HLPD broilers had lower duodenal villus width than the SPD birds. The duodenal crypt depth and ileal mucosal thickness were higher in the HLPD group than in other groups. The HLPD and LLPD enhanced the ileal villus height compared to the SPD. The LLPD and HLPD treatments did not affect meat quality traits compared to the SPD treatment.CONCLUSIONDietary HMB could be a conducive approach to reducing dietary protein for broilers until 21 days old.This article is protected by copyright. All rights reserved.