title: Fermentation of six different forages in the semi-continuous fermentation technique Caesitec.
abstract: The aim of the present study was to compare carbohydrate degradation of forages which store carbohydrates either predominantly as fructan or starch, in horses' hindgut. The effects of an abrupt change from hay-based feeding to green fodder-based feeding on the caecal flora were tested with the in vitro hindgut simulation technique 'Caesitec'. Six trials with different forages (English ryegrass, tall fescue, grass mixture-horses, grass mixture-cows, lucerne, white clover) were conducted. During a 4-day stabilisation period, samples were taken once a day before loading the fermenters with hay. After diet-change to forage-based feeding, samples were taken four times a day. Ammonia and pH-value were measured before and 1, 2 and 6 h after loading the 'Caesitec'. Gas formation was measured daily. Bacterial numbers, lactate and short chain fatty acids were detected at four time-points of each trial. The grass mixtures contained the highest amounts of fructan. The pH-values were in the physiological range from pH 6 up to 7 (6.58-6.83) by feeding all forages. Gas formation, anaerobic and aerobic bacterial numbers increased after diet change from hay to any forage. The maximum amount of fructan (3.75 g/kg) in swiss pasture did not cause a permanent pathological change in the hindgut-flora.
authors.affiliation: Institute of Animal Nutrition, Vetsuisse-Faculty University of Zurich, Zurich, Switzerland. judith-vosmer@gmx.de
authors.forename: J
authors.initials: J
authors.lastname: Vosmer
authors.forename: A
authors.initials: A
authors.lastname: Liesegang
authors.forename: M
authors.initials: M
authors.lastname: Wanner
authors.forename: A
authors.initials: A
authors.lastname: Zeyner
authors.forename: D
authors.initials: D
authors.lastname: Suter
authors.forename: L
authors.initials: L
authors.lastname: Hoelzle
authors.forename: B
authors.initials: B
authors.lastname: Wichert
mesh_terms: D000641:Ammonia; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000737:chemistry; D005285:Fermentation / Q000502:physiology*; D006602:Hexosyltransferases; D006736:Horses / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid; D000455:Medicago sativa / Q000737:chemistry / Q000378:metabolism*; D006109:Poaceae / Q000737:chemistry / Q000378:metabolism*; D013213:Starch; D029921:Trifolium / Q000737:chemistry / Q000378:metabolism*
chemical_list: D002241:Carbohydrates; D019344:Lactic Acid; D000641:Ammonia; D013213:Starch; D006602:Hexosyltransferases; C105700:fructan - fructan 6G-fructosyltransferase