Effect of Biochar Type and Size on in Vitro Rumen Fermentation of Orchard Grass Hay

Abstract

Biochar, a byproduct from the biofuels industry, may be a potential feed additive in ruminant diets due to possible improvements in microbial fermentation. Therefore, the objective of this study was to determine the nutritive value, in vitro digestibility, volatile fatty acid (VFA) production, and gas production of biochar inclusion to an orchard grass (Dactylis glomerata) basal diet. The study was designed as a 3 × 2 factorial arrangement with 3 different biochar sources and 2 biochar processed sizes as the main effects factors. Experimental treatments were biochar from 3 different tree types: 1) Chestnut Oak (Quercus prinus L.; CO), 2) Yellow Poplar (Liriodendron tulipifera; YP), or 3) White Pine (Pinus strobus L.; WP), and processed at 2 different biochar particle sizes: a) <178 μm (Fine) or b) >178 μm (Coarse). Biochar was added to the basal diet of orchard grass hay (872.35 g/kg of DM, 98.31 g/kg of CP, and 704.02 g/kg of aNDF, DM basis) at a rate of 81 g/kg DM.