Tropentag, September 17 - 19, 2018 in Ghent "Global food security and food safety: The role of universities"

Applying in vitro Gas Production Technique to Assess the Nutritive Value of Gmelina arborea Leaves

¹Lead City University, Dept. of Microbiology, Nigeria
²Tai Solarin University of Education, Agricultural Science, Nigeria

Abstract

In vitro gas fermentation method was used to evaluate the nutritive value of different forms of Gmelina arborea leaves. Two experiments were conducted. Experiment 1 involved the determination of chemical composition of green, yellow and brown leaves. In experiment 2 , the nutritive value of green, yellow and brown leaves of Gmelina arborea was assessed by in vitro gas production technique for total gas production over a period of 24 hr and to predict organic matter digestibility (OMD), metabolisable energy (ME) and short chain fatty acid (SCFA). Methane volume (CH₄) was measures after incubation at 24 hr. The in vitro gas production (IVGP) characteristics (insoluble degradable fraction (b), potential degradability (a+b), rate of degradation (c) and effective degradation (ED)) were also predicted.
Results revealed that the chemical composition of green, yellow and brown leaves varied significantly (p<0.05). Dry matter ranged from 80.15 to 91.24 % in green and brown leaf respectively. Same trend was observed for neutral detergent fibre, it ranged from 60.92 to 63.77%. The crude protein ranged from 24.84 to 26.44% in brown and green leaves respectively. The IVGP, ME, SCFA and methane production were not significant (p>0.05), except OMD. Same trend was observed for all the in vitro gas fermentation parameters with the green leaf recording the highest value, while the lowest values were obtained in the brown leaf. They ranged between 3.75 and 4.25 ml/200 mg DM; 3.27 and 3.49 MJ kg^-1 DM; 0.10 and 0.94 µmol; 1.5 and 3.0 ml/200 mg DM in brown and green leaf respectively. OMD ranged significantly from 41.57 to 45.05 % in yellow and green leaf respectively. The a, b, a+b, c and ED also did not vary significantly.
It can be concluded that Gmeilna arborea leaf has potential in ruminant nutrition and any of the forms can serve as fodder in the tropics.

Keywords: Chemical composition, Gmelina arborea leaves, in vitro gas production, nutritive value

Contact Address: Oluwanike Abiola-Olagunju, Lead City University, Dept. of Microbiology, Toll Gate Area, Ibadan, Nigeria, e-mail: nikkymakky07yahoo.com