Chemical characterisation of Moringa oleifera (MO) leaves and the apparent digestibility of MO leaf meal-based diets offered to three chicken strains

Abstract

The utility of Moringa oleifera leaves as a nutraceutical component of chicken diets depends on the leaves’ chemical composition and in vivo digestibility, parameters that are largely unknown. Therefore, this study investigates the chemical composition of M. oleifera leaves at different stages of maturity as well as the apparent digestibility of M. oleifera leaf meal (MOLM)-based diets when offered to three chicken strains. Tender and mature leaves were separately harvested from 12 individual trees and stored separately for processing and chemical analyses. The leaves were air-dried in a well-ventilated laboratory to constant weight and milled to pass through a 1 mm sieve before being analysed for proximate and mineral components. A mixture of tender and mature leaves was also collected from all the trees and bulked before being similarly processed to produce a bulk leaf meal. The bulk leaf meal was used to dilute a commercial broiler finisher diet at 0 (MOLM0), 25 (MOLM25), 50 (MOLM50), and 100 (MOLM100) g/kg DM, producing four isoenergetic and isonitrogenous diets whose digestibility was evaluated in 90-day old Potchefstroom koekoek (PK), Ovambo (OV) and Black Australop (BA) chickens. Crude protein content was significantly higher in tender (324.63 g/kg DM) than in mature (285.2 g/kg DM) leaves. Tender leaves had higher concentrations of Ca (19.15 g/kg) and P (4.15 g/kg). However, Fe content for mature leaves (150.5 dpm) was higher compared to tender leaves (110.5 dpm). The level of phenolics was higher in mature leaves. In BA chickens, the control diet (MOLM0) had highest crude protein digestibility (87.0%) followed by MOLM100 (85.4%). In OV and PK strains, diets with higher levels of MOLM had higher crude protein digestibility. It can be concluded that the inclusion of MOLM in chicken diets did not negatively affect nutrient digestibility in OV and PK chickens, thus there is potential to utilize this feed resource for improved productivity in these extensively-reared chickens.