关键词: 瘤胃降解蛋白平衡, 瘤胃发酵, 产气量, 甲烷产量, 体外

Abstract: This experiment was conducted to study the effects of RDPB（RDPB，g·kg-1 DM） on rumen fermentation, total gas and methane production in vitro. AnkomRFgas production system was used by random block design, with 6 different rumen degradable protein balance (RDPB) diets, namely diet 1（-20 g·kg-1 DM）, diet 2(-10 g·kg-1 DM), diet 3(0 g·kg-1 DM), diet 4 (10 g·kg-1 DM), diet 5 (20 g·kg-1 DM) and diet 6 (30 g·kg-1 DM), with 2 replicates, respectively, culturing for 24 h. The results showed that: (1) The fermentation broth pH, acetic acid / propionic acid, amount of gas production and CH4 production of and diet 3（P<0.01） or diet 4（P<0.01） showed the lowest level. (2) Volatile fatty acids, acetic acid, propionic acid, butyric acid and rumen ammonia concentration increased with the increase of the balance value of the degradation, therefore, changing the balance of dietary rumen degradable protein could affect the rumen fermentation. The balance of rumen degradable protein had no significant effect on the total amount of volatile fatty acids and protozoa. (3) Concentration of methane at different time points and 24 h methane production were affected by dietary rumen degradable protein balance. Methane production of diet 4 （P<0.05） was lower than that of other diets. Thus, in vitro culture conditions, dietary RDPB affected rumen pH, ammonia nitrogen (NH3N), volatile fatty acids (VFA) concentration, gas and CH4 production. The results indicated that appropriate RDPB was 010 g·kg-1 DM, considering its effect on rumen fermentation and methane production.

Key words: rumen degradable protein balance (RDPB), rumen fermentation, gas production, methane production, in vitro