title: Interaction between milk allowance and fat content of the starter feed on performance of Holstein calves.
abstract: Sixty-six Holstein male calves [42 ± 6.0 kg of body weight (BW) and 12 ± 3.1 d of age] were housed individually and allocated to 1 of 4 treatments following a 2 × 2 factorial complete randomized design to assess the potential interaction between milk replacer (MR) allowance and fat content in the starter feed. Thus, 4 treatments were evaluated: a low-fat (4.1% fat; LF) starter feed offered along with 4 L/d of MR (4 LF), a high-fat (11.2% fat; HF) starter feed plus 4 L/d of MR (4 HF), a LF starter feed offered with 6 L/d of MR (6LF), and an HF starter feed offered with 6 L/d of MR (6 HF). Calves were fed either 4 or 6 L/d of MR (25% crude protein and 19.2% fat) in 2 offers (0800 and 1630 h) and had ad libitum access to either an LF or an HF starter feed (21.4 and 22.3% crude protein). Calves were weaned at wk 6 of study by halving the daily MR allowance for 1 wk. Individual MR and starter feed intakes were recorded daily and BW was determined weekly. A glucose tolerance test was performed on d 30 of study to evaluate the effects of increased energy provision on glucose metabolism. Apparent feed digestibility was measured for the last 5 d of study. Overall, fat content of starter feed had no effect on solid feed intake. However, during wk 8 of study (after weaning), calves in the LF treatment had greater starter feed intake than HF calves. Calves on 6 L/d of MR had greater BW than calves fed 4 L/d from the second week of study until weaning. After weaning, 6 LF calves had lesser BW than 6 HF calves. Calves on 6 L/d of MR had greater average daily gain than calves fed 4 L/d, and 6 HF calves tended to have the greatest average daily gain. Glucose clearance rate tended to be lesser for HF than for LF calves. In conclusion, offering 6 L/d of MR increased growth performance before weaning and, when offering 6 L/d of MR, feeding a high-fat starter feed resulted in the greatest BW after weaning.
authors.affiliation: Department of Ruminant Production, Institut de Recerca i Tecnologia Agroalimentaries (IRTA), Torre Marimon, 08140 Caldes de Montbui, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Araujo
authors.affiliation: Department of Ruminant Production, Institut de Recerca i Tecnologia Agroalimentaries (IRTA), Torre Marimon, 08140 Caldes de Montbui, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Terré
authors.affiliation: Department of Ruminant Production, Institut de Recerca i Tecnologia Agroalimentaries (IRTA), Torre Marimon, 08140 Caldes de Montbui, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain. Electronic address: alex.bach@irta.cat.
authors.forename: A
authors.initials: A
authors.lastname: Bach
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002417:Cattle; D004041:Dietary Fats / Q000008:administration & dosage* / Q000032:analysis; D004044:Dietary Proteins / Q000008:administration & dosage / Q000032:analysis; D005951:Glucose Tolerance Test; D007333:Insulin Resistance; D008297:Male; D008892:Milk / Q000737:chemistry*; D041941:Milk Substitutes / Q000737:chemistry; D014886:Weaning
chemical_list: D001786:Blood Glucose; D004041:Dietary Fats; D004044:Dietary Proteins
keywords: calf; energy; fat; growth; starter grain