Blood and ruminal fluid profiles in carbohydrate-foundered cattle.
The relationships of acetylhistamine and histamine to the clinical signs of carbohydrate-induced acidosis were investigated in beef steers. Blood pH and plasma L-lactic acid decreased and serum sodium, serum potassium, ruminal fluid L-lactic acid, ruminal fluid histamine, and ruminal fluid and blood acetylhistamine increased in carbohydrate-engorged steers as compared with the changes in the steers while feeding on pasture (forage-fed steers). Twelve to 14 hours after the steers had become engorged, clinical signs of laminitis ("feedlot founder") were observed in three of six steers. These signs appeared 4 to 6 hours after blood acetylhistamine attained maximal concentration (2.9997 +/- 1.7054 microgram of histamine base/ml of blood) and blood pH decreased to 7.260 +/- 0.026 at 8 hours after engorgement. Blood histamine value reached 0.1298 +/- 0.1095 microgram of histamine base/ml 4 hours after engorgement (8 to 10 hours before the appearance of clinical illness), but had reached maximal concentration 32 hours after engorgement (0.3300 +/- 0.028 microgram of histamine base/ml of blood).
D000818:Animals; D001769:Blood; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000378:metabolism*; D004040:Dietary Carbohydrates / Q000009:adverse effects*; D006632:Histamine / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000097:blood; D008297:Male; D012417:Rumen / Q000378:metabolism*
D004040:Dietary Carbohydrates; D007773:Lactates; D006632:Histamine