title: Rumen dry matter degradability and apparent digestibility of variously treated rice hulls.
abstract: Rice hulls from Hungary, Colombia, and Cambodia were used for measuring with the nylon bag method the dry matter degradability in the rumen of sheep. After 48 h rumen incubation time the dry matter loss varied between 10.0 and 27.7%. The 48 h rumen dry matter loss of rice hulls from Hungary increased from 14.0 (untreated control) only to 17.9, 20.1, and 17.0% after chemical treatment with 2% NaOH, 4% CaO, and 4% urea, respectively. gamma-irradiation with doses of 0, 0.1, 0.25, 0.5, 1, and 2 MGy effected rumen dry matter losses of unground rice hulls from Hungary of 6.4, 14.5, 13.5, 21.3, 37.1, and 70.5%. The apparent digestibility of organic matter of untreated rice hulls from Hungary amounted to 19.2%, as found in tests with wethers. The main reasons of low digestibility and the negligible effect of chemical treatments are the high contents of lignin (ca. 15%) and silica (up to 23% of the dry matter). Therefore rice hulls are not suitable as feedstuff for ruminants.
authors.affiliation: Wissenschaftsbereich Tierernährungschemie, Karl-Marx-Universität Leipzig, Jena, DDR.
authors.forename: G
authors.initials: G
authors.lastname: Flachowsky
authors.forename: W I
authors.initials: WI
authors.lastname: Ochrimenko
authors.forename: H
authors.initials: H
authors.lastname: Koch
authors.forename: G
authors.initials: G
authors.lastname: Güther
authors.forename: M
authors.initials: M
authors.lastname: Bär
mesh_terms: D000821:Animal Feed; D000818:Animals; D002160:Cambodia; D003105:Colombia; D004063:Digestion; D006814:Hungary; D008031:Lignin / Q000378:metabolism; D008297:Male; D012275:Oryza; D012417:Rumen / Q000378:metabolism*; D012756:Sheep / Q000378:metabolism*; D012995:Solubility
chemical_list: D008031:Lignin