Effects of pre-weaning plane of milk replacer and feeding frequency on glucose metabolism in dairy calves

• Author / Creator

  MacPherson, Jayden A R

• Feeding dairy calves large milk meal sizes at a low feeding frequency has been associated with reduced insulin sensitivity in previous literature. Therefore, the aim of this thesis was to investigate the influence of feeding an elevated plane of milk on glucose metabolism in calves pre- and post-weaning. To assess insulin sensitivity in calves in chapter 2 and 3, postprandial plasma glucose and insulin concentrations (pre-weaning), as well as insulin response to a glucose tolerance test (GTT; pre and post-weaning) were evaluated. In addition, in chapter 2 the rate of abomasal emptying was characterized pre-weaning to determine the extent of its control over glucose appearance in the blood. Results from chapter 2 where calves were fed a low (4 L/day) or a high (8 L/day) plane of milk twice daily indicated that calves fed either treatment did not experience hyperglycemia or hyperinsulinemia. Additionally, responses to a GTT were similar pre- or post-weaning suggesting both treatments had similar glucose tolerance at all ages. Abomasal emptying was reduced in calves fed a larger meal size (4 L) which indicates it can be used to modulate the appearance of glucose in the blood to prevent hyperglycemia. In chapter 3, feeding an elevated plane of milk (8 L/day) fed over four (4x; meal size 2 L) or two meals per day (2x; meal size 4 L) was compared. Neither treatment resulted in a state of hyperglycemia or hyperinsulinemia, and responses to the GTT were similar indicating similar glucose tolerance. Overall findings from this thesis suggest that calves fed an elevated plane of milk do not experience reduced insulin sensitivity when fed at differing frequencies of 2 or 4 times a day or when compared to calves fed a low plane of milk (4 L/day). These results have significant implications for the dairy industry as this means dairy operations can feed calves more milk, up to 8 L fed over two meals a day, allowing for greater pre-weaning growth without compromising glucose metabolism pre- or post-weaning.

• Subjects / Keywords

  • Feeding frequency
  • Calf nutrition
  • Glucose and insulin
  • Plane of nutriton
  • Abomasal emptying

• Graduation date

  2016-06

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R36D5PN4G

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.