Effect of Protein Fractionation and Buffer Solubility of Forage Sources on In Vitro Fermentation Characteristics, Degradability and Gas Production

Abstract

Buffer solubility and protein fractionation were evaluated from the hays (timothy, alfalfa and klein) and straws (tall fescue and rice), and in vitro trial was conducted to examine the effect of buffer extraction on fermentation characteristics, degradability and gas (CO2 and CH4) production. Buffer soluble protein (SP) content and A fraction in total protein were highest in alfalfa hay as 61% and 41.77%, respectively while lowest in rice straw (42.8% and 19.78%, respectively). No difference was observed in B1 fraction among forages but B2 fraction was slightly increased in klein hay (12.34%) and tall fescue straw (10.05%) compared with other forages (6.34~8.85%). B3 fraction of tall fescue was highest as 38.49% without difference among other forages while C fraction was highest in rice straw. pH in incubation solution was higher in all forages after extraction than before extraction at 3h (P<0.01) and 6h (P<0.05), and pH from hays of timothy and alfalfa was higher than the other forages at 6h (P<0.05) and 12h (P<0.001). Regardless of extraction, ammonia-N concentration from alfalfa hay was increased at all incubation times and extraction effect was appeared only at 3h incubation time (P<0.01). Total VFA concentration from alfalfa hay was highest up to 24h incubation while those from tall fescue straw and rice straw were lowest. Buffer extraction decreased (P<0.01~P<0.001) the total VFA concentration. Acetic acid proportion was increased (P<0.001) before extraction of forages but no difference was found between forages. Propionic acid(C3) proportion was also increased(P<0.001) before extraction in all forages than in straws at 3h, 24h and 48h incubations, and C3 from hays were mostly higher (P<0.05) than from straws. Butyric acid proportion, however, was not affected by extraction at most incubation times. Parameter 'a' regarding to the dry matter (DM) degradation was increase (P<0.001) in all forages before extraction, and was decreased (P<0.05) in tall fescue straw and rice straw compared with hays. Parameter 'b' was also increased (P<0.001) before extraction but no difference was found between forages. Effective degradability of DM (EDDM) was higher (P<0.001) before extraction in most forages except for rice straw. Buffer extraction

Effect of Defaunation on In Vitro Fermentation Characteristics and Methane Emission When Incubated with Forages

“…The strong relationship between total gas production and EDDM has been previously reported (Jin et al, 2012). Regardless of defaunation, more gas was produced from forages than from cellulose (Table 4).…”

“…Furthermore, ryegrass showed similar results in comparison with cellulose, and seemed to be more potent in increasing total VFA concentration than both rice straw and tall fescue. This might be associated with the relatively low degree of lignification and high buffer solubility in ryegrass (Jin et al, 2012). It can be indicated that degradation of ryegrass is less limited by lignin and more rapidly available for rumen microbes, contribution to more VFA production.…”

Changes in ruminal fermentation and blood metabolism in steers fed low protein TMR with protein fraction-enriched feeds

“…Table 1). 이것은 기존 연구에서 보고된 각 단백질의 N 분획과 전체적으로 유사하였으나 (Licitra et al, 1996;Jin, 2011;Choi, 2015), 채종박의 경우 B 2 fraction이 A와 B 1 fraction보다 다소 높게 나타났다. .…”

Effects of CNCPS fraction-enriched proteins on ruminal fermentation and plasma metabolites in holstein steers fed TMR containing low protein

“…단백질 fraction별 대표사료를 선정하기 위해 기존의 문 헌을 통해 후보사료를 1차 검색 후 그 중 fraction별 함유량 이 높고 국내에 사용되고 있는 사료로 선발하였다 (Choi, 2003;Choi et al, 2015;Jin, 2011;Licitra et al, 1996).…”

“…(Table 1). 이것은 기존 연구에 서 보고된 각 단백질의 N 분획과 전체적으로 유사하였다 (Choi, 2003;Jin, 2011;Licitra et al, 1996) Treatments were TMR only (control), TMR with rapeseed meal (AB1), TMR with soybean meal (B2) and TMR with perilla meal (B3C), respectively. b) Standard error of the mean.…”