Volatile Fatty Acids and Ammonia Levels in Local Sheep’s Rumen Fluid Fed with Fermented Rice Straw

摘要

This study aims to determine the effects of providing suspension of Acetobacter liquefaciens bacterial isolate and Geotrichum sp. fungi isolate, as well as a mix between Acetobacter liquefaciens and Geotrichum sp. isolates extracted from the faeces of girrafes feeding on rice straw on pH value and Volatile Fatty Acids (VFA) and ammonia levels in Local sheep’s rumen fluid. This experiment utilized twenty Local sheep randomly divided into four treatments where each treatment consisted of five repetitions, thus Completely Randomized Design method was applied (four treatments by five repetitions). The four treatments were T0: 60% (rice straw fermented without isolates+ 3% of urea + 3% of molasses) + 40% of concentrates, T1: 60% (rice straw fremented with Acetobacter liquefaciens bacteria + 3% urea + 3% molasses) + 40% of concentrates, T2: 60% (rice straw fermented with Geotrichum sp. fungi isolates + 3% of urea + 3% of molasses) + 40% concentrates, and T3: 60% (fermented rice straw with Acetobacter liquefaciens and Geotrichum sp. isolates + 3% of urea + 3% of molasses) + 40% of concentrates. The isolates of Acetobacter liquefaciens bacteria and Geotrichum sp. fungi were extracted from giraffes’ faeces kept in Safari Park, Pandaan, East Java. At the end of this three months study, the rumen fluid was collected using a vacuum pump. The variables were then measured including pH value and the levels of VFA and ammonia. The result of the research shows that local sheep fed with rice straw fermented with suspension of Acetobacter liquefaciens bacteria, Geotrichum sp. fungi, as well as a mixture of Acetobacter liquefaciens and Geotrichum sp. experienced an increase on their pH level as well as the VFA and ammonia levels in their rumen fluid. The provision of the suspension of cellulolytic bacteria isolate mixture of Acetobacter liquefaciens and Geotrichum sp. fungi in the fermentation of rice straw yields the highest levels of acetic, propionic, butyric acids and total of Volatile Fatty Acids in Local sheep’s rumen fluid.