Nutritional Evaluation of Conventional Feedstuffs for Ruminants using InVitro Gas Production Technique

Abstract

The use of crop residues and agricultural by-products in animal feeding is a very common practice in Myanmar. Nutritive values and fermentation characteristics of natural grass (NG), lablab bean stalk-fresh (LLBF), butter bean residue-dry (BBRD), sesame residue-dry (SRD), sorghum stover-dry (SSD) and sorghum stover-fresh (SSF) were evaluated through in vitro gas production method. The crude protein (CP) content of Lablab bean stalk-fresh (LLBF) was significantly higher than those of other feedstuffs with the least CP obtained from sorghum stover-dry (SSD). The contents of NDF, ADF and EE ranged from 58.95 to 80.03, 36.63 to 67.76 and 2.15 to 2.89, respectively. The cumulative gas volumes at 24 hrs ranked from the highest to the lowest; BBRD, NG, SRD, LLBF, SSD and SSF. However, the gas volume of SSD was significantly higher (P<0.05) than those of other feedstuffs at the 96 hrs of incubation time. The highest gas production rate “c” was found in SRD and the lowest was in SSD. While the fermentation of insoluble fraction “b” of SSD was significantly higher (P<0.05) than those of other feedstuffs, the LLBF was the highest in the fermentation of quickly soluble fraction “a”. The estimated total carbohydrate (TC), non fibre carbohydrate (NFC), metabolizable energy (ME), organic matter digestibility (OMD), short chain fatty acid (SCFA) and methane gas concentration are significantly different (P<0.05) among the experimental feedstuffs. According to the findings of this study, all of these conventional feedstuffs have the good potential to be used as ruminant feed.