Effects of potassium buffers on feed intake in lactating dairy cows and on rumen fermentation in vivo and in vitro

• Published in: Journal of dairy science Vol. 69; no. 1; pp. 124 - 134
• Main Authors: West, J.W, Coppock, C.E, Nave, D.H, Schelling, G.T
• Format: Journal Article
• Language: English
• Published: United States Am Dairy Sci Assoc 01.01.1986; American Dairy Science Association
• Subjects: ACIDE GRAS; ACIDOS GRASOS; Animals; BICARBONATE; BICARBONATES; BICARBONATOS; BOVIN LAITIER; BUFFERS; Cattle; COMPORTEMENT ALIMENTAIRE; COWS; DAIRY CATTLE; DIET; DIETA; FATTY ACIDS; FEED INTAKE; Feeding Behavior - drug effects; FEEDING HABITS; Female; FERMENTACION; FERMENTATION; GANADO DE LECHE; HABITOS ALIMENTARIOS; Hydrogen-Ion Concentration; In Vitro Techniques; INGESTION DE PIENSO; LACTACION; LACTATION; MILK YIELD; POTASIO; POTASSIUM; Potassium - pharmacology; Pregnancy; PRISE ALIMENTAIRE (ANIMAUX); REGIME ALIMENTAIRE; RENDEMENT LAITIER; RENDIMIENTO LECHERO; RUMEN; Rumen - drug effects; Rumen - physiology; SODIO; SODIUM; SOLUCIONES REGULADORAS; TAMPON; VACA; VACHE
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(86)80376-9

Twenty-four Holstein cows were used to compare acceptance of concentrates and complete rations containing 1) no buffer, 2) 1.8% potassium bicarbonate, 3) 1.2% potassium carbonate, or 4) 1.5% sodium bicarbonate in the concentrate. When concentrate and a forage blend were offered separately (comparison period 1), concentrate intake did not differ among treatments, but forage blend consumption and complete ration intake was greater with the potassium carbonate ration (comparison period 2). Rumen pH did not differ, but urine pH was higher in cows fed complete rations containing buffers. Cows fed potassium carbonate had higher milk fat percentages than cows fed sodium bicarbonate during the first comparison period and higher than controls during the second comparison period and produced more 3.5% fat-corrected milk and solids-corrected milk than cows fed sodium bicarbonate in both comparison periods. Milk protein percentage was lower in cows fed potassium carbonate diets as compared with those fed sodium bicarbonate diets, but total protein production was similar. In three continuous culture in vitro trials, potassium carbonate maintained fermenter pH comparably to sodium bicarbonate, and total volatile fatty acid and acetate production were similar.