Structural Growth, Rumen Development, and Metabolic and Immune Responses of Holstein Male Calves Fed Milk Through Step-Down and Conventional Methods
- 1 July 2007
- journal article
- research article
- Published by American Dairy Science Association in Journal of Dairy Science
- Vol. 90 (7), 3376-3387
- https://doi.org/10.3168/jds.2007-0104
Abstract
Structural growth, feed consumption, rumen development, metabolic response, and immune response were studied in Holstein calves fed milk through either a conventional method or a step-down (STEP) method. In the conventional method, calves (n = 20) were fed colostrum and then milk at a rate of 10% of their BW for the entire period of 44 d. In the STEP method, calves (n = 20) were given colostrum and then milk at a rate of 20% of their BW for 23 d, which was reduced (between d 24 to 28) to 10% of their BW for the remaining 16 d. The calves on both methods were weaned gradually by diluting milk with water between d 45 and 49. After weaning, feed consumption, structural growth, and body weight gain were monitored until calves were 63 d of age. At d 63, twelve calves (6/treatment) were euthanized and rumen papillae length, papillae width, rumen wall thickness, and emptied forestomach weight were recorded. At wk 4, 7, and 9, ruminal contents were collected to enumerate rumen metabolites. The STEP-fed calves consumed a greater amount of milk than conventionally fed calves during the pre-STEP (d 1 to 28), post-STEP (d 29 to 49), and preweaning (d 1 to 49) periods. Consumption of starter and hay was greater during the pre-STEP period and lesser during the post-STEP and postweaning (d 50 to 63) periods in calves on the conventional method than on the STEP method. Body weight gain and structural growth measurements of calves were greater on the STEP method than on the conventional method. A hypophagic condition caused by greater milk consumption depressed solid feed intake of STEP-fed calves during the pre-STEP period, and a hyperphagic response caused by a reduced nutrient supply from milk triggered their consumption of solid feed during the post-STEP and postweaning periods. Ruminal pH and concentrations of ammonia, total volatile fatty acids, acetate, propionate, butyrate, and plasma beta-hydroxybutyrate were higher in calves on the STEP method and at weaning and postweaning (d 63) were lower in calves on the conventional method. Emptied weight of the forestomach, rumen wall thickness, papillae length, papillae width, and papillae concentration were higher in calves on the STEP method than in those on the conventional method. Blood glucose was lower, and blood urea nitrogen and beta-hydroxybutyrate at weaning and postweaning were higher in STEP-fed calves. Serum IgG, IgA, and triglycerides for 1, 2, and 3 wk of age were higher in calves on the STEP method than in those on the conventional method. In conclusion, greater feed consumption, BW gain, and structural growth, and a more metabolically and physically developed rumen were observed in calves on the STEP method than in those on the conventional method.Keywords
Funding Information
- National Livestock Research Institute,
- Rural Development Administration,
This publication has 27 references indexed in Scilit:
- Rumen Development, Intestinal Growth and Hepatic Metabolism In The Pre- and Postweaning RuminantJournal of Dairy Science, 2004
- Development and Analysis of a Rumen Tissue Sampling ProcedureJournal of Dairy Science, 2004
- Composition and Functional Capacity of Blood Mononuclear Leukocyte Populations from Neonatal Calves on Standard and Intensified Milk Replacer DietsJournal of Dairy Science, 2003
- Feed Intake Patterns, Growth Performance, and Metabolic and Endocrine Traits in Calves Fed Unlimited Amounts of Colostrum and Milk by Automate, Starting in the Neonatal PeriodJournal of Dairy Science, 2002
- Effects of Ad Libitum Milk Intake on Dairy CalvesJournal of Dairy Science, 2002
- Effects of Feeding Milk Replacer Once Versus Twice Daily on Glucose Metabolism in Holstein and Jersey CalvesJournal of Dairy Science, 2002
- The Somatogenic Hormones and Insulin-Like Growth Factor-1: Stimulators of Lymphopoiesis and Immune FunctionEndocrine Reviews, 1997
- The Somatogenic Hormones and Insulin-Like Growth Factor-1: Stimulators of Lymphopoiesis and Immune FunctionEndocrine Reviews, 1997
- Cold housing and computer-controlled milk feeding for dairy calves: behaviour and performanceAnimal Science, 1993
- Does drinking milk stimulate sucking in young calves?Applied Animal Behaviour Science, 1992