Effect of Single and Mixed Strain Probiotics on Volatile Fatty Acid Production and Methane Emission in Lactating Dairy Cows

Abstract

The major role of probiotics in diets of ruminants is to modulate rumen metabolism which enhances nutrient utilization efficiency and animal performance. Mixed strain/species probiotics may enhance the capability of colonizing the gastro-intestinal tract, combining the different mechanisms of each strain/species in a synergistic way. Methane, a by-product of rumen fermentation is considered to have negative effects in herbivores as it results in gross energy loss    to the environment.  Moreover, methane gas emanating from enteric fermentation in ruminants is major contributor of greenhouse gas emission that significantly leads to global warming which is major threat to sustainable livestock production globally. A study to determine the effect of single and mixed strain probiotics on methane emission in dairy cows was conducted. Gas produced during in-vitro gas production was siphoned from each sample and taken for rumen methane analysis using a GC-flame ionization detection (FID) gas chromatography. Data was subjected to analysis of variance using General Linear Model and mean separation done using Tukey’s (HSD) test at 0.05 significant level. Results of rumen methane emission showed that probiotic supplementation had a significant effect on methane gas emission. Methane emission varied between 68, 267.861 ml (Treatment 5) and 73.265 ml (T4). A combination of Lactobacillus plantarum and Saccharomyces cerevisiae decreased rumen methane emission when used in modulation in dairy cows and therefore pointing to a synergistic effect between the two microorganisms.