The rumen of cattle is inhabited by complex microbiota that play an important role in facilitating the feed fermentation process. Therefore, its nutrient requirements must also be taken into consideration. Nutrient requirements for rumen microbes can be met from rumen degradable protein (RDP) and non-fiber carbohydrate (NFC). Nutrients that are easily degraded in the rumen can be seen from their metabolite products such as total gas production, gas kinetics, and methane gas production. This study aims to determine the effect of the balance of rumen degradable protein (RDP) with non-fiber carbohydrate (NFC) in cattle rations on total gas production, gas kinetics and methane gas production in vitro. The study used an experimental method with a completely randomized design (CRD). There were six treatments of RDP balance with NFC, namely R1 (1.7), R2 (1.5), R3 (1.8), R4 (1.6), R5 (1.4), and R6 (1.3) with five replications. Research data were processed by analysis of variance and Duncan’s multiple range test. The results showed that the balance of RDP:NFC in the ration gave no significant effect (P>0.05) on total gas production, maximum gas production, and methane gas production. However, it had a significant effect (P<0.05) on the cumulative gas production rate. The conclusion of this study is that the balance of RDP:NFC in cattle ration is a more important factor in feed formulation.
Keywords | Rumen degradable protein, Non-fiber carbohydrate, Total gas production, Gas kinetics, Methane gas