title: Effect of feeding regimen on concentration of free endotoxin in ruminal fluid of cattle.
abstract: The influence of concentrate diets on endotoxin concentration in sterile filtrate of ruminal fluid was assessed in ruminally fistulated Jersey cows. Three cows underwent a change in diet from hay to a diet containing 3.0 kg and 14 d later 6.0 kg of a 12% CP concentrate. The cows had free access to water and a mineral-stone. A modified Limulus Amoebocyte Lysate technique was used for the endotoxin analyses. The endotoxin concentration in the ruminal fluid of cows fed on hay were 148 +/- 84 and 118 +/- 50 endotoxin units (EU)/mL (mean +/- SD) on two separate days and increased from the 2nd d of supplementation with 3.0 kg of concentrate to 408 +/- 198 EU/mL on d 5. When the cows were fed 6.0 kg of concentrate, the endotoxin concentrations increased to 1,599 +/- 944 EU/mL. To assess the influence on the ruminal endotoxin concentration of an adaptation of the ruminal environment to concentrate before hyperalimentation, four ruminally fistulated Jersey cows previously fed either hay or a high-concentrate diet for 1 mo were hyperalimented with 60 to 70 g of barley per kilogram BW. A relative increase in ruminal endotoxin concentration was determined only in the two cows previously fed concentrates. The results show that high-concentrate diets do not consistently relate to increases of ruminal endotoxin concentrations.
authors.affiliation: Department of Clinical Studies, Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
authors.forename: P H
authors.initials: PH
authors.lastname: Andersen
authors.forename: B
authors.initials: B
authors.lastname: Bergelin
authors.forename: K A
authors.initials: KA
authors.lastname: Christensen
mesh_terms: D000222:Adaptation, Physiological; D000821:Animal Feed; D000818:Animals; D002417:Cattle / Q000378:metabolism*; D004435:Eating; D004731:Endotoxins / Q000032:analysis*; D005069:Evaluation Studies as Topic; D005260:Female; D006863:Hydrogen-Ion Concentration; D008033:Limulus Test / Q000662:veterinary; D009994:Osmolar Concentration; D012417:Rumen / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D004731:Endotoxins