In vitro Effect of Garlic Oil and Turmeric Extract on Methane Production from Gas Test Medium

Abstract

Aims: To evaluate the effect of garlic oil and turmeric extract on rumen fermentation and methane emission using an in vitro gas production technique. Study Design: Completely randomized design. Place and Duration of Study: Department of animal science, Faculty of agriculture, Ferdowsi University of Mashhad, between November 2012 and June 2013. Methodology: Treatments were: control (no additives); 10 mg/L of cultural fluid of monensin (MO) as a positive control; 20, 40 and 80 mg/L of cultural fluid of garlic oil (GA20, GA40 and GA80 respectively); 20, 40 and 80 mg/L of cultural fluid of turmeric extract (TU20, TU40 and TU80 respectively). All treatments were incubated for 96 h and gas production was recorded by a pressure transducer at 2, 4, 6, 8, 12, 24, 48, 72 and 96 h of incubation. At 24 h post incubation, pH of cultural medium and methane production were determined. Results: Supplementation of MO and GA80 resulted in a significant reduction in total gas production compared with the control. Furthermore, addition of garlic oil at 80 mg/L strongly decreased methane production during 24 h post incubation (43% lower than the control). Mid and high concentrations of turmeric extract (TU40 and TU80) caused to increase in vitro dry matter disappearance (IVDMD) in comparison with the control. Partitioning factor