In ovo administration of ethanolic extracts of sweet orange peel, ginger and their combinations: effects on post-hatch growth performance, apparent nutrient digestibility and health status of broiler chickens

Abstract

ABSTRACT In ovo administration of bioactive nutrients can mitigate poor hatchability, suboptimal growth, and weak innate immunity in broiler chicks. This study evaluated the effect of in ovo administration of ethanolic sweet orange peel extract (ESOPE), ginger extract (EGE) and their equal combinations (BLD) on egg hatchability, post-hatch growth performance, apparent nutrient digestibility and health status of broiler chickens. A total of 900 fertile Cobb 500 broiler eggs (58 ± 2 g) were randomly allocated to five treatments consisting of 180 eggs with six replicates of 30 eggs each. The treatments were: un-injected eggs (UIE), eggs injected at day 6 with 0.02 mL distilled water (DW), ESOPE, EGE and an equal blend of ESOPE and EGE (BLD). Egg incubation was maintained at 37.8 °C and a relative humidity of 60%. Parameters including incubation variables, Tona chick quality scores, post hatch growth performance, nutrient digestibility, haematological and serum indices, gut morphometry and caecal microflora were measured and analyzed using one-way analysis of variance in a completely randomized design. Means were separated using Tukey’s test at p < 0.05. Hatchability was significantly higher (p < 0.05) in the ESOPE group compared to the DW group. In ovo injection of eggs with ESOPE also improved (p < 0.05) chick weight and hatch yield compared to UIE and DW groups. At the finisher phase, Hatchlings from ESOPE had improved (p < 0.05) weight gain and feed conversion ratio compared with the UIE group. Dry matter digestibility improved in all extract groups when compared with DW group. The BLD group recorded increased (p < 0.05) duodenal and jejunal villi height compared to the UIE group and achieved complete suppression of caecal Staphylococcus aureus compared to other treatment . In conclusion, in ovo injection with these extracts, especially ESOPE at 0.02 mL per egg improved hatchability and growth performance of broiler chickens. Future studies should employ a dose-response design (0.02, 0.04, and 0.06 mL) to identify the precise threshold for optimal embryonic development.