Supplementation of Nicotinic Acid for Lactating Holstein Cows Under Heat Stress Conditions

• Published in: Journal of dairy science Vol. 80; no. 6; pp. 1200 - 1206
• Main Authors: Di Costanzo, A., Spain, J.N., Spiers, D.E.
• Format: Journal Article
• Language: English
• Published: Savoy, IL Elsevier Inc 01.06.1997; Am Dairy Sci Assoc; American Dairy Science Association
• Subjects: Animal productions; Animals; Biological and medical sciences; Body Temperature - drug effects; Body Temperature - physiology; Body Temperature Regulation - drug effects; Body Temperature Regulation - physiology; Cattle - physiology; Cattle Diseases - etiology; Cattle Diseases - prevention & control; COLA (ANATOMIA ANIMAL); COMPLEMENT ALIMENTAIRE; CONDICION CORPORAL; CONTENIDO DE LIPIDOS; CONTENIDO DE MATERIA SECA; CONTENIDO PROTEICO; ECHANGE GAZEUX; ESTRES TERMICO; ETAT CORPOREL; Feeding. Feeding behavior; Female; Food, Fortified; Fundamental and applied biological sciences. Psychology; GAIN DE POIDS; GANANCIA DE PESO; GRASA DE LA LECHE; heat stress; Hot Temperature - adverse effects; HUMEDAD RELATIVA; HUMIDITE RELATIVE; Humidity; INGESTION DE PIENSOS; INTERCAMBIO DE GASES; Lactation - physiology; MATIERE GRASSE DU LAIT; METABOLITE; METABOLITOS; NICOTINAMIDA; NICOTINAMIDE; nicotinic acid; Nicotinic Acids - administration & dosage; Nicotinic Acids - pharmacology; PLASMA SANGUIN; PLASMA SANGUINEO; PRISE ALIMENTAIRE (ANIMAUX); PROTEINAS DE LA LECHE; PROTEINE DU LAIT; QUEUE; Random Allocation; REGION DU CORPS; REGIONES DEL CUERPO; RENDEMENT LAITIER; RENDIMIENTO LECHERO; Seasons; Skin Temperature - drug effects; Skin Temperature - physiology; STRESS THERMIQUE; Stress, Physiological - etiology; Stress, Physiological - prevention & control; Stress, Physiological - veterinary; SUPLEMENTOS; TEMPERATURA DEL CUERPO; TEMPERATURE CORPORELLE; TENEUR EN LIPIDES; TENEUR EN MATIERE SECHE; TENEUR EN PROTEINES; Terrestrial animal productions; VACAS LECHERAS; VACHE LAITIERE; vasodilation; Vasodilation - drug effects; Vasodilation - physiology; Vasodilator Agents - pharmacology; Vertebrates; Vertebrates: anatomy and physiology, studies on body, several organs or systems; VITAMINAS; VITAMINE; heat stress; NA; THI; vasodilation; TCI; nicotinic acid; Glc; Farming animal; Bovine; Animal feeding; Ruminant animal; Nicotinic acid; Dairy cattle; Thermoregulation; Summer; B-Vitamins; Stress; Vasodilation; Vertebrata; Mammalia; Diet; Female; Complementation; Artiodactyla; Ungulata; Hot weather
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(97)76048-X

Twenty-six lactating Holstein cows (90 d of lactation) were blocked according to milk production, parity, and days of lactation for assignment to one of two dietary treatments. Diets included a control diet with no supplemental niacin and a diet supplemented with increasing concentrations of niacin (12, 24, or 36 g/d per cow over three consecutive 17-d periods. Cows were housed in a covered free-stall barn and were fed and milked twice daily. Mean maximum air temperatures and temperature-humidity indexes were 28.5, 31.4, and 25.2°C and 79.6, 85.1, and 75, respectively, for the three periods. Rectal temperature was measured with a rectal probe, tail and rump temperatures by infrared thermometry, and respiratory rate by visual observation. Measurements were made daily at 0800, 1600, and 2200h. Rectal temperature was not affected by treatment. Comparison of skin temperatures for control cows and cows fed niacin showed higher temperatures at the tail (34.0 vs. 33.7°C at 0800h; 35.1 vs. 34.8°C at 1600h, respectively) and rump (34.1 vs. 33.7°C at 0800h; 35.3 vs. 35.0°C at 1600h, respectively) for control cows during period 1. No differences in thermal responses were observed during period 3. Niacin did not significantly increase milk production but decreased skin temperatures during periods of mild or severe heat stress.