Evaluating dried pomegranate peel as a functional feed additive: effects on growth, carcass traits, and gut health in broilers

Abstract

This study investigated the impact of dietary supplementation with dried pomegranate peel (DPP) on growth performance, carcass attributes, blood parameters, and cecal microbiota of broiler chickens. A total of 120 one-day-old Ross 308 broiler chicks were randomly assigned to three experimental groups: a control group (basal diet without any supplementation), and two treatment groups with diets supplemented with 1% and 2% DPP, respectively. Growth performance was monitored weekly, and carcass attributes were measured at the end of the 42-days trial. Blood samples were collected for biochemical analysis, and cecal microbiota (total bacterial count, E. coli and salmonella) was assessed. Results indicated that DPP supplementation significantly reduced body weight, body weight gain, and feed consumption compared to the control group, particularly at 21 and 42 days. Birds fed 2% DPP showed a better feed conversion ratio (FCR) but body weight was reduced during both the starter period and overall experimental period, while those fed 1% DPP had an improved FCR only during the starter phase but showed a worsened FCR during the finisher and overall period. DPP supplementation also significantly increased the relative weights of the eviscerated carcass, liver, heart, gizzard, and spleen while reducing abdominal fat. Blood analysis revealed no significant effects on protein or liver enzymes, but DPP reduced glucose, cholesterol, HDL, and triglyceride levels. Additionally, DPP reduced the cecal counts of total bacteria, E. coli, and Salmonella. Histological analysis revealed that DPP supplementation improved bursal and ileal structures, enhancing immunity and gut health. In conclusion, DPP supplementation, particularly at 2%, improved gut health, reduced abdominal fat, and modulated microbial populations but adversely affected growth performance due to reduced feed palatability. These findings suggest that DPP may be a functional feed additive with health-promoting benefits, though further research is needed to optimize its inclusion level.

Keywords: Broiler chicks; Feed additives; Growth performance; Health status; Pomegranate peel.

Fig. 1

Effect of supplementing broiler diets with different pomegranate peel on histomorphometry of bursa of Fabricius. A Control group. B 1% O group. C) 2% O group. The bordered area in A showed follicle area, the bordered area in B showed area of plica, and the bordered area in C showed number of follicles

Fig. 2

Effect of supplementing broiler diets with different pomegranate peel on histomorphometry of ilium. A Control group. B 1% P group. C) 2% P group. The red line in A showed length of the villi, the yellow line in B showed depth of the crypt, and the green line in C showed thickness of the muscle layer