Determination of the Effects of Some Plant Extracts on Rumen Fermentation and Protozoal Counts by Hohenheim <em>In Vitro</em> Gas Production Technique

Abstract

The aim of the present study was to determine the effects of some plant extracts on rumen fermentation and protozoal counts by using Hohenheim in vitro gas production technique in cattle. In this study in vitro gas productions at varying doses of thymol, oregano, zingiber and syzygium essence oils were determined at 2, 4, 8, 12, 24, 36 and 48 (h), respectively. For all feed types, high doses (50 ppm) of thymol and oregano supplementations significantly decreased gas production at later hours of incubation (p<0.05). On the other hand, for all feed types, all doses of zingiber and syzygium supplementations significantly increased gas production at later hours of incubation (p<0.05). High total gas production quantity indicates that most of the substrates are converted to gas which results in decreased concentrations of volatile fatty acids and other beneficial end products. Varying doses of all essence oils were assessed within the same incubation periods and it was found that high doses of thymol and oregano supplementations resulted significant decrease in gas production (p<0.05). For all feed types, the highest protozoal counts were identified in Z. officinale 200 pmm group compared to positive and negative control groups, while the lowest protozoal count for TMR was recorded in T. vulgaris, O. vulgare and S. aromaticium groups. These essence oils can be utilized as rumen regulators. Similar effects are anticipated with the supplementation of these oils to ruminant rations (in vivo), which, therefore, will lead to improved ruminant performance.