Effect of dietary clove basil, Ocimum gratissimum, leaves extract on healing of artificially wounded African catfish, Clarias gariepinus (B.), juveniles

Abstract

ABSTRACT African catfish, Clarias gariepinus (B.), may be wounded naturally due to cannibalism, high density, and/or any other action. These wounds may be a precursor to further pathogen infection, causing health deterioration and economical loss if not well treated. Hence, the wound-healing capability of clove basil (Ocimum gratissimum) leaves extract (CBLE) on African catfish was investigated. A basal diet containing 40% crude protein was formulated and enriched with CBLE levels of 0.0, 5, 10, and 15 g/kg diet. Fish (54.20 ± 1.12 g) were lacerated (1 cm long) in the caudal and lateral regions. After that fish were fed one of the tested diets in a complete randomized design for 14 days, during which wound closures and histological changes were observed. Fish fed CBLE-enriched diets had faster wound-healing percentages and daily healing rates over those fed the control diet. Fish fed lower CBLE levels needed more time to achieve complete wound healing; meanwhile fish fed the 15 g/kg diet showed a complete wound healing (100%) on the 10th and 8th day postwound (dpw) in both lateral and caudal regions respectively. Wound healing in caudal and lateral regions of CBLE-fed fish in response to time period was related to the accumulation of bioactive compounds in fish, which enhanced their antioxidant and immunity. On the 14th dpw, the least healing percentage (88.09%) was recorded in the lateral and caudal regions in fish fed the control diet. On the other hand, the dermal wound in the caudal region healed faster than that in the lateral one; this was because of the variation in tissue composition and texture in both regions.