# Vitex Agnus-Castus Extract Supplementation Enhanced Growth Performance, Hemato‐Biochemical Parameters, Intestinal Histomorphometry, Flesh Composition, and Quality of Nile Tilapia, Oreochromis niloticus

## TL;DR

This study shows that adding Vitex agnus-castus extract to Nile tilapia feed improves their growth, health, and meat quality.

## Contribution

The study introduces Vitex agnus-castus extract as a beneficial natural feed additive for Nile tilapia.

## Key findings

- VAC5 group showed the best growth performance and improved feed conversion and protein efficiency.
- VAC5 and VAC10 groups had improved hematological parameters and better liver function indicators.
- Intestinal structure and muscle composition improved with VAC supplementation at 5–10 g/kg.

## Abstract

Plant‐derived extracts offer a promising alternative to synthetic additives in fish feed, with the aim of enhancing growth, health, and sustainable production. The present study aimed to evaluate the effect of the hydroalcoholic extract of dietary Chaste tree, Vitex agnus-castus (VAC), on growth performance, feed utilization, digestive enzymes, hematological, serum biochemical parameters, intestinal histomorphometry, and flesh composition and quality of Nile tilapia, Oreochromis niloticus. A total of 160 Nile tilapia fingerlings were allocated in five equal treatments and fed increasing levels of VAC extract (0, 5, 10, 15, and 20 g/kg of diet) and referred as control, VAC5, VAC10, VAC15, and VAC20, respectively, for 8 weeks. Fish in the VAC5 group achieved the highest growth performance, digestive enzyme activities, and significantly improved feed conversion ratio (FCR) and protein efficiency ratio (PER). The predicted maximum VAC level supplementation was 9.81 g kg–1 diet as determined by quadratic regression based on growth and feed utilization. The hematological parameters increased significantly in the VAC5 and 10 groups. Liver function enzymes, glucose (GLU), triglycerides (TGs), and creatinine were significantly decreased, while total protein (TP) and albumin (ALB) were significantly increased in fish fed VAC5 and VAC10 diets. However, total cholesterol (TCH) was significantly increased with VAC supplementation on a level‐dependent basis. Histometric investigation of the intestinal tract revealed a significant improvement in muscular and submucosal thickness, villi length, and width. The chemical composition of the muscle revealed an improvement in protein and dry matter in the VAC5 group, with decreased water loss during storage, dripping, and freezing. In conclusion, VAC extract can be used as a feed additive in the Nile tilapia diet at levels of 5–10 g kg–1 diet with a positive response in growth, physiological response, and histological architecture.