Effects of dietary fat with or without nicotinic acid on nutrient flow to the duodenum of dairy cows

• Published in: Journal of dairy science 1996-08, Vol.79 (8), p.1410-1424
• Main Authors: Christensen, R.A. (Rutgers University, New Brunswick, NJ.), Overton, T.R, Clark, J.H, Drackley, J.K, Nelson, D.R, Blum, S.A
• Format: Article
• Language: English
• Subjects: ALFALFA; ALMIDON; AMIDON; Animal Nutritional Physiological Phenomena; Animal productions; Animals; Biological and medical sciences; Cattle - physiology; Cholesterol - blood; COMPLEMENT ALIMENTAIRE; CONSOMMATION ALIMENTAIRE; CONSUMO DE ALIMENTOS; CONTENIDO DE MATERIA SECA; CORPS GRAS; DIETA; Dietary Fats - pharmacology; DIGESTIBILIDAD; DIGESTIBILITE; DIGESTION; DIGESTION DU RUMEN; DIGESTION RUMINAL; Duodenum - metabolism; ENSILADO; ENSILAGE (PRODUIT); Fats; Fatty Acids, Volatile - metabolism; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Glycine max; GRASAS; HAYLAGE; HENIFICADO; INGESTION DE PIENSOS; Lactation; LUZERNE; MAIS; MAIZ; MATERIA ORGANICA; MATIERE ORGANIQUE; Medicago sativa; Niacin - pharmacology; NICOTINAMIDA; NICOTINAMIDE; PRISE ALIMENTAIRE (ANIMAUX); REGIME ALIMENTAIRE; Rumen - metabolism; SEBO; SOJA; SUIF; SUPLEMENTOS; TENEUR EN MATIERE SECHE; Terrestrial animal productions; Triglycerides - blood; Urea - blood; VACAS LECHERAS; VACHE LAITIERE; Vertebrates; Vertebrates: anatomy and physiology, studies on body, several organs or systems; VITAMINAS; VITAMINE; Zea mays
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(96)76499-8

Four Holstein cows, fitted with ruminal and duodenal cannulas, were utilized in a 4 X 4 Latin square design to investigate the effects of supplementing nicotinic acid to diets that contained 35% alfalfa haylage, 15% corn silage, and either 50% of a low fat concentrate or 10% whole raw soybeans and 40% of a high fat concentrate containing tallow. Treatments in a 2 X 2 arrangement were 1) low fat, no supplemental nicotinic acid; 2) low fat, 12 g/d of nicotinic acid; 3) high fat, no supplemental nicotinic acid; and 4) high fat, 12 g/d of nicotinic acid. The DMI and OM apparently and truly digested in the rumen and apparently digested postruminally were not different among treatments. Addition of fat to the diet decreased the concentration of total VFA in ruminal fluid but did not alter the molar proportions of any of the VFA; supplementation of nicotinic acid tended to decrease the molar proportion of acetate. Amounts of NAN, microbial N, nonammonia nonmicrobial N, and AA that flowed to the duodenum were similar among diets. The concentration of urea N in plasma decreased, and concentrations of cholesterol and triglycerides increased, when cows were fed supplemental fat. Milk composition and production of milk, 4% FCM, and milk components were not altered by addition of fat or nicotinic acid to the diet. Supplementation of fat or nicotinic acid to diets of dairy cows was not beneficial in this experiment