Effect of Concentrate: Roughage Ratio and the Addition of Kefir on the Production Characteristics of Ruminant in vitro

The stability of the gut ecosystem, especially the rumen, is an important area of ​​research that has an impact on the use of feed additives and is associated with a number of diseases. The current study aimed to survey the effect of concentrate: roughage (C: R) ratio and the addition of kefir on the production characteristics of in vitro ruminant fermentation. In a ۵x۶ factorial order, six ratios of C: R (۱۰۰:۰, ۸۰:۲۰, ۶۰:۴۰, ۴۰:۶۰, ۲۰:۸۰ and ۰:۱۰۰) and five doses of kefir (۰, ۰.۸, ۱.۶, ۲.۴, and ۳.۲ ml) were used, respectively. Gas production during incubation was estimated at ۰- ۹۶ h. During inoculation, the rumen fluid was obtained at ۰, ۴, ۸, ۱۲, and ۲۴ h of incubation. Cumulative gas production, GPDM, GPOM, and GPNDF at ۲۴ h was highest at the C: R ratio of ۱۰۰:۰ (۶۷.۸۲ mL, ۷۵.۹۲ mL/ ۲۰۰ mg, ۱۹۷۹.۱۵ mL/۲۰۰ mg, and ۱۱.۱۱ mL/ ۲۰۰ mg, respectively). The kefir addition improved the kinetics and gas production significantly. The highest in vitro dry matter and organic matter digestibility (IVDMD and IVOMD) were obtained at the C: R ratio of ۱۰۰:۰ (۹.۲۶% and ۱۸۲.۲% higher than those in C: R ratio of ۰:۱۰۰, respectively). The increase of concentrate diet ratio improved the overall volatile fatty acids (TVFA). No interaction effect on the gas production was detected between the C: R ratio and kefir. The microorganism populations were influenced neither by the level of concentrate nor by the level of kefir. Consequently, the high concentrate-to-roughage ratio and the addition of ۱.۶ mL kefir to the overall dietary substrate could promote rumen fermentation and feed digestibility without affecting microbe counts.

کلیدواژه ها:

Concentrate: Roughage ، Gas production ، In vitro Ruminal Fermentation ، Kefir