Effects of Feeding Dry Glycerin to Early Postpartum Holstein Dairy Cows on Lactational Performance and Metabolic Profiles

• Published in: Journal of dairy science 2007-12, Vol.90 (12), p.5682-5691
• Main Authors: Chung, Y.-H., Rico, D.E., Martinez, C.M., Cassidy, T.W., Noirot, V., Ames, A., Varga, G.A.
• Format: Article
• Language: English
• Subjects: 3-Hydroxybutyric Acid - blood; Animal Feed; Animal Nutritional Physiological Phenomena - physiology; animal performance; Animal productions; Animals; Biological and medical sciences; Blood Glucose - metabolism; blood metabolic profile; blood sampling; Cattle - metabolism; Cattle - physiology; cow feeding; dairy cows; dietary supplements; early postpartum dairy cow; feed intake; Female; Food industries; Fundamental and applied biological sciences. Psychology; glycerin; glycerol; Glycerol - administration & dosage; Glycerol - pharmacology; Holstein; Ketones - urine; lactation; Lactation - drug effects; metabolism; Milk - secretion; Milk and cheese industries. Ice creams; milk composition; milk yield; postpartum interval; Postpartum Period; Pregnancy; Random Allocation; Rumen - metabolism; ruminant nutrition; Terrestrial animal productions; Vertebrates
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.2007-0426

Effects of feeding a dry glycerin product (minimal 65% of food grade glycerol, dry powder) to 39 multiparous Holstein dairy cows (19 control and 20 glycerin-supplemented; lactation number = 2.2±1.3 SD) on feed intake, milk yield and composition, and blood metabolic profiles were investigated. Dry glycerin was fed at 250 g/d as a top dressing (corresponding to 162.5g of glycerol/d) to the common lactating total mixed ration from parturition to 21 d postpartum. Individual milk was sampled from 2 consecutive milkings weekly and analyzed for components. Blood was sampled from the coccygeal vein at 4, 7, 14, and 21 (±0.92, pooled SD) d in milk and analyzed for urea nitrogen, glucose, insulin, nonesterified fatty acids, and β-hydroxybutyrate. Urine was tested for the acetoacetate level weekly by using Ketostix. Average feed intake, milk yield and components, blood metabolites, and serum insulin concentrations were not affected by dry glycerin supplementation. Glycerin-supplemented cows experienced a more positive energy status (higher concentrations of plasma glucose, lower concentrations of plasma β-hydroxybutyrate, and lower concentrations of urine ketones), which was observed during the second week of lactation, suggesting that energy availability may have been improved. This glucogenic effect of dry glycerin did not result in an increase in feed intake or milk yield during the first 3 wk of lactation, likely because of the relatively less negative energy status of cows transitioning into lactation. The tendency toward higher milk yield for glycerin-supplemented cows during wk 6 of lactation (52 vs. 46kg/d) after the supplementation period (dry glycerin was terminated at wk 3 of lactation) suggested a potential benefit of dry glycerin on subsequent milk production, perhaps through changes in metabolism, which requires further investigation.