title: Improving the quality of rice straw by urea and calcium hydroxide on rumen ecology, microbial protein synthesis in beef cattle.
abstract: Four rumen-fistulated beef cattle were randomly assigned to four treatments according to a 4 × 4 Latin square design to study the influence of urea and calcium hydroxide [Ca(OH)2 ] treatment of rice straw to improve the nutritive value of rice straw. Four dietary treatments were as follows: untreated rice straw, 50 g/kg urea-treated rice straw, 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw and 30 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw. All animals were kept in individual pens and fed with concentrate at 0.5 g/kg of BW (DM), rice straw was fed ad libitum. The experiment was conducted for four periods, and each period lasted for 21 days. During the first 14 days, DM feed intake measurements were made while during the last 7 days, all cattle were moved to metabolism crates for total faeces and urine collections. The results revealed that 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw improved the nutritive value of rice straw, in terms of dry matter intake, digestibility, ruminal volatile fatty acids, population of bacteria and fungi, nitrogen retention and microbial protein synthesis. Based on this study, it could be concluded that using urea plus calcium hydroxide was one alternative method to improve the nutritive value of rice straw, rumen ecology and fermentation and thus a reduction of treatment cost.
authors.affiliation: Tropical Feed Resources Research and Development Center (TROFREC), Faculty of Agriculture, Khon Kaen University, Muang, Thailand; Department of Animal Science, Faculty of Natural Resources, Rajamangala University of Technology-Isan, Phang Khon, Thailand.
authors.forename: S
authors.initials: S
authors.lastname: Polyorach
authors.forename: M
authors.initials: M
authors.lastname: Wanapat
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001419:Bacteria / Q000145:classification / Q000187:drug effects; D001426:Bacterial Proteins / Q000096:biosynthesis; D002126:Calcium Hydroxide / Q000737:chemistry*; D002417:Cattle; D004032:Diet / Q000662:veterinary; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D008297:Male; D012275:Oryza / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry*; D012417:Rumen / Q000187:drug effects* / Q000382:microbiology; D014508:Urea / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D014508:Urea; D002126:Calcium Hydroxide
keywords: calcium hydroxide [Ca(OH)2]; microbial protein; rice straw; rumen ecology; ruminants; urea