The effects of infused olive leaf offered with drinking water on growth performance, ileum histomorphologic characteristics, and some cecal microorganism counts of broiler chickens.

The aim of the study was to investigate the effects of infused olive leaves (IOL) in drinking water on the growth performance, carcass characteristics, ileal histomorphology, and cecal microorganisms of broiler chickens. A total of 210 day-old male broiler chicks were randomly divided into 5 treatment groups with 6 replicates and 7 chicks in each replicate. All chicks received a corn-soybean-based diet and drinking water with or without IOL ad libitum for 42 days. Treatments were drinking water without any additives (control group), drinking water including IOL of 5 m/L (IOL5), 10 m/L (IOL10), 15 ml/L (IOL15), and 20 ml/L (IOL20). The addition of IOL to drinking water did not affect the growth performance, water intake, carcass parameters, weights of inner organs, and digestive tract weight and length. The Escherichia coli and Lactobacillus spp. counts in the cecum were also not influenced by IOL supplementation in drinking water. However, chickens receiving IOL5, IOL10, or IOL15 had higher villus length in the ileum compared with birds in the control group. Crypt depth was lower in chickens from the IOL20 group compared with birds in the other treatment groups. In addition, broilers offered IOL15 or IOL20 had a higher villus length to crypt depth ratio in the ileum than chickens in the control group. However, treatments had no influence on the lamina muscularis mucosae layer of the ileum in broiler chickens. The results showed that drinking water including IOL at 15 and 20 ml/L improved ileal histomorphology without any detrimental effect on growth performance, carcass traits, and cecal microorganisms in broiler chickens.