A Comparison of the Effect of Grass pea Treatment, on Estimated Metabolizable Energy through in Vitro Methods

For treatment of Anti-Nutritional Factors(ANFs), (β-N-oxalyl -L- α, β -diaminopropionic acid (β-ODAP) and Condensed Tannin (CT)) in grass pea, some such alkali treatments as NaOH, NaHCO3, KMnO4 and wood ash, besides water soaking and polyethylene glycol (PEG) (6000 MW) were employed. Metabolizable Energy (ME) of treated and of untreated grass pea was assessed using gas production technique, two-stage in vitro digestibility technique as well as chemical composition determination. merely NaOH treatment significantly increased ME in two step digestibility method. In ME calculation that using gas production, the ME content of grass pea was 8.52 (MJ/Kg DM), while water soaking and PEG revealed the highest levels of, 11.48 and 10.96 (MJ/Kg DM), respectively. There were negative significant correlations observed between β-ODAP concentration and both OMD (-0.47) as well as DOMD (-0.48). There was no negative effect of CT content of grass pea on dry matter digestibility (correlation 0.55). As regards high crude protein content, percent of β-ODAP reduction and ME content, either one of NaOH or water soaking treatments are recommended as the most suitable treatments as regards grass pea.