Morphological Modulation of Broiler Organs in Response to an Organic Acid–Phytogen Composite in Healthy Broilers

In this study, we investigated broiler growth traits, intestinal health and immune aggregates in response to supplementation of Origanum vulgare and Cinnamomum verum , citric acid and malic acid in drinking water at varying levels and durations on broiler. We randomly allocated 140 day-old broilers into four (4) groups, with each group having seven replicates ( n = 5). A basal diet and water were provided to all the groups ad libitum in accordance with standard farming practices. Keeping group I as the control, group II was supplemented with 1 mL/3.3 L of water for 1–4 days, 1 mL/4 L from 15–18 days and 1 mL/4 L water from 26–29 days. Group III and IV were supplemented with 1 mL/4 L of water and 1 mL/6 L of water for 35 days, respectively. After the completion of the trial (day 35), two broilers per replicate (14 birds per group) were slaughtered to sample the visceral organs. The results demonstrated that the feed conversion ratio (FCR) and body weight gain improved ( p ≤ 0.05) during the fourth and fifth week of the trial in group III in comparison to the control group. Although the small intestine villus height and villus-height-to-crypt-depth ratio improved ( p ≤ 0.05) in group III, the muscularis externa thickness of the ileum was highest ( p ≤ 0.05) in the control group. Similarly, the lymphatic follicular and nodular area of the immune organs improved ( p ≤ 0.05) in group III. In all segments of the small intestine (duodenal, jejunal and ileal), the number of acidic and total goblet cells was highest ( p ≤ 0.05) in group II. In conclusion, dietary Origanum vulgare, Cinnamomum verum , citric acid and malic acid at the dose of 1 mL/4 L of drinking water (group III) was the most effective in improving the growth performance, gut development and associated immune components in broilers.