Chemical composition and gross energy content of commonly available animal feedstuff in Sri Lanka

Abstract

The aim of the present study was to evaluate the chemical composition and gross energy content of currently available feedstuff used for animal feeding in Sri Lanka. A total of 35 feedstuff including 10 energy supplements, 11 plant protein supplements, 3 animal protein supplements, 2 mineral supplements, 3 grasses, and leaves of 6 tree species was evaluated. Proximate composition, van Soest fiber content, in vitro dry matter digestibility, gross energy (GE) and mineral content of the feedstuff were measured using standard protocols. Values were expressed as percentage dry matter (DM) for proximate constituents and van Soest constituents, and kcalg-1 DM for gross energy content. The crude protein (CP) content of plant protein supplements varied from 24.4 % DM [black gram (Vigna mungo) husk] to 61.3 % DM (corn gluten meal); however animal protein supplements had less variation in CP content [varied from 50.3 % DM (meat & bone meal) to 69.2 % DM (fish meal)]. Portia (Thespesia populnea) leaves had more CP (15.9 % DM) and ether extract (EE) content (9.9 % DM) than all other roughages except manilkara leaves (Manilkara hexandra), which had 15.4 % DM EE. Cocoa (Theobroma cacao) husk contained the highest crude fibre content (38.3 % DM) when compared to all the other evaluated ingredients. GE content was highest in brewery waste (4.78 kcalg -1 DM) and lowest in coconut distillery waste (2.97 kcalg -1 DM). Mineral content of animal protein supplements was higher than in the other concentrates and roughages. In vitro dry matter digestibility of the concentrates was higher than that of roughages. The same trend was observed in organic matter digestibility. The data collected from the current study will be useful for balanced ration formulation for animals living under farm conditions in Sri Lanka.