Influence of dietary fat sources and lysolecithin on growth performance, visceral organ size, and histological intestinal alteration in broiler chickens

The aim of this study was to investigate the influence of dietary fat sources and lysolecithin on growth performance, visceral organ size, and histological intestinal alterations in broiler chickens. Ninety-six 7-d-old male broiler chickens were assigned to 8 treatments in a 2 x 4 factorial arrangement of treatments with 2 levels of lysolecithin (0 and 145 mg/kg) and 4 different fat sources [poultry fat (PF), yellow grease from Kagoshima (YG1), yellow grease from Kashima (YG2), and yellow grease from Hachinohe (YG3)]. Each treatment had 4 replicates of 3 broiler chickens per cage until 49 d of age. There was no difference in BW gain due to fat sources, lysolecithin, or lysolecithin x fat source interaction throughout the experiment. By feeding lysolecithin, feed efficiency increased (P < 0.05) during the growth period of 7 to 21 d of age, and the weights of the duodenum, ileum, and total intestine decreased (P < 0.05). Intestinal villus height, villus area, and cell area were not different among treatment groups, except that ileal villus height tended to decrease and ileal cell area tended to increase (P=0.077) by feeding lysolecithin. Increased duodenal cell mitosis and decreased jejunal tunica muscularis thickness were observed (P < 0.05) by feeding lysolecithin. Furthermore, on the villus apical surface, more protuberated cells, cell clusters, and deeper cells at the sites of recently exfoliated cells were observed by feeding lysolecithin. However, the protuberant cells were not different among treatment groups. The Integrated Fluorescence Density Values of Anti-Cluster of Differentiation 36 reaction in the jejunum were significantly greater in the lysolecithin-fed groups, except YG2. These results indicate that feeding lysolecithin improves feed efficiency during 7 to 21 d of age regardless of the fat type, and causes epithelial hypertrophy. (C) 2015 Elsevier B.V. All rights reserved.