Use of in vitro gas production technique to evaluate the effects of microwave irradiation on sorghum (Sorghum bicolor) and wheat (Triticum sp.) nutritive values and fermentation characteristics


Effects of microwave irradiation (900 W) for 3, 5 and 7 min on the nutritive value of sorghum and wheat grains were evaluated by in vitro gas production technique. Gas volume was recorded at 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 h of incubation and kinetics of gas production were estimated using model: GP = A exp {– exp [1 + (be/A) (LAG – t)]}. Cumulative gas production at 24 h was used for estimation of metabolizable energy, net energy for lactation, short chain fatty acids, digestible organic matter and microbial protein. For sorghum grain, microwave irradiation increased cumulative gas production for most times of incubation linearly. Microwave treatments for 5 and 7 min increased the A fraction linearly in both cereal grain, whereas the maximum rate of gas production (b) decreased linearly only in wheat grain. Microwave treatments for 3, 5 and 7 min increased (P<0.05) metabolizable energy, net energy for lactation and short chain fatty acids content of sorghum grain, but not of wheat grain. It was concluded that microwave irradiation changed the gas production parameters resulting changed ruminal fermentation characteristics that can be considered in ration formulation.

Key words: sorghum grain, wheat grain, microwave irradiation, in vitro gas production

Volume 2, Number 2 (2013) pp. 125-130   [ Full Text (PDF) ]