Effect of feeding ajwain (Trachyspermum ammi) seed as a feed additive on enteric methane production and rumen ecosystem in murrah buffaloes

The present study, comprising of two experiments, was conducted to study the effect of ajwain seeds (Trachyspermum ammi) as feed additive on methane emission, nutrient utilization and rumen fermentation in male buffaloes. In the first experiment, 15 intact animals were divided into three equal groups and assigned to three treatments: T1 (control) animals were fed basal diet without additive, while animals under T2 and T3 were fed the basal diet with ajwain seeds at 1 and 2 per cent DM intake. The basal diet consisted of wheat straw and concentrate mixture in 50:50 ratio. The DM intake, BW gain, FCR and nutrient digestibility were similar among the three groups. The methane emission in terms of L/d and L/kg DMI were comparable in all the groups, whereas, in terms of L/kg digestible DM intake it was reduced by 18% (P=0.029) in T3 as compared to T1. In the second experiment, three rumenfistulated animals were used in a switch over design with the same three dietary treatments. The results indicated that the rumen fluid pH, concentration of ammonia N, activities of carboxymethyl cellulase, xylanase and avicelase, protozoal count as well as the population density of total bacteria, Fibrobacter succinogenes, methanogens, fungi and protozoa as assessed by real time PCR did not show any significant differences among the groups. It is concluded that dietary supplementation of ajwain at 2% of DM intake is capable of reducing methane emission in buffaloes without affecting the performance of the animals.