Dietary oregano essential oil improved the growth performance via enhancing the intestinal morphometry and hepato-renal functions of common carp (Cyprinus carpio L.) fingerlings

The current work was designed to assess the influences of dietary oregano essential oil (OEO) on the indices of growth and feed utilization, proximate composition, hepato-renal functions, and histomorphological criteria of livers, kidneys, and intestines of common carp (Cyprinus carpio L.) fingerlings. Fish (20.3 ± 0.8 g) were randomly divided into five treatments and fed on different levels of OEO at 0, 5, 10, 15, and 20 g/kg diet for 2 months. The results showed that the dietary OEO significantly improved the growth parameters (final body weight, weight gain, weight gain %, specific growth rate, and feed intake) (P