Effects of Dietary α-Amylase on Metabolism and Performance of Transition Dairy Cows

• Published in: Journal of dairy science Vol. 88; no. 12; pp. 4405 - 4413
• Main Authors: DeFrain, J.M., Hippen, A.R., Kalscheur, K.F., Tricarico, J.M.
• Format: Journal Article
• Language: English
• Published: Savoy, IL Elsevier Inc 01.12.2005; American Dairy Science Association
• Subjects: 3-Hydroxybutyric Acid - blood; alpha-Amylases - administration & dosage; Ammonia - analysis; amylase; Animal Nutritional Physiological Phenomena; Animal productions; Animals; Biological and medical sciences; Blood Glucose - analysis; Butyrates - analysis; Cattle - physiology; Cell Count; Diet - veterinary; Dietary Supplements; Fatty Acids, Nonesterified - blood; Fatty Acids, Volatile - analysis; Female; Fermentation - drug effects; Food industries; Fundamental and applied biological sciences. Psychology; Insulin - blood; Lactation - drug effects; Lactation - physiology; Milk - chemistry; Milk - cytology; Milk and cheese industries. Ice creams; Postpartum Period; Pregnancy; Rumen - chemistry; Rumen - metabolism; Terrestrial animal productions; transition dairy cow; Vertebrates; β-hydroxybutyrate; β-hydroxybutyrate; transition dairy cow; amylase; AMA; Farming animal; Amylase; Enzyme; Dairy cattle; Metabolism; Vertebrata; Mammalia; Glycosidases; Dairy industry; Hydrolases; Artiodactyla; α-Amylase; Performance; Amylolytic enzyme; O-Glycosidases; Ungulata
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(05)73127-1

Twenty-four multiparous Holstein cows [body weight, 759kg (SD=30kg); body condition score, 3.2 (SD=0.13)] were used in a randomized complete block design to determine the effect of feeding α-amylase during the transition period on rumen fermentation, key metabolic indicators, and lactation performance. Cows were assigned to either a control diet or the control diet supplemented with α-amylase (662 fungal amylase units per gram, AMA) at 0.1% of diet dry matter (DM). Experimental diets were fed from 21 d before expected calving through 21 d in milk. From 22 to 70 d in milk, all cows were fed a similar lactation cow diet. Average pre- and postpartum DM intakes were 12.4 and 17.8 kg/d, respectively, and did not differ between treatments; however, DM intakes during the last week prepartum decreased to a greater degree in AMA than control cows compared with wk −2. Supplementing diets with α-amylase tended to increase proportions of ruminal butyrate prepartum but not postpartum. Treatment differences were not detected for concentrations of insulin in plasma and lipid and glycogen in liver tissue. Prepartum, concentrations of β-hydroxybutyrate and nonesterified fatty acids were increased in cows fed AMA compared with the control diet. Postpartum, concentrations of glucose in plasma tended to be increased by feeding AMA. Increased plasma β-hydroxybutyrate and nonesterified fatty acids pre- but not postpartum and a tendency for increased plasma glucose postpartum demonstrate shifting reliance from lipid- to carbohydrate-based metabolism postpartum in cows fed α-amylase.