Effects of heat-treatment of colostrum on the development of calves in the neonatal and pre-weaned periods

• Author / Creator

  Kent-Dennis, Coral E

• Calves are born agammaglobulinemic and must ingest vital immunoglobulins via colostrum for protection from infection during the neonatal period. Colostrum also contains many other biologically active factors, such as growth factors, immune cells and antimicrobial peptides, which are important for development, growth and health of the calf. Although essential to the calf, colostrum also represents one of the earliest sources of exposure to infectious pathogens. Pasteurization of milk and colostrum is becoming a common practice used to reduce vertical transmission of pathogens to young calves. Recently, there has been a growing interest in the effects of heating colostrum on its components and on the development of calves. The objective of this study was to investigate the effects of heat-treatment of colostrum on gut absorption and development in bull calves in the first 12 hours of life, and the effects of absorption, growth and health in pre-weaned heifer calves. Bull calves (n=23) and heifer calves (n=17) were fed 2L of either unheated or heat-treated colostrum within an hour after birth. In the first experiment, absorption of IgG and β-lactoglobulin (BLG), villus height and crypt depth of the ileum and ileal goblet cell number were measured in bull calves. Bulls that received heat-treated colostrum had 18% lower plasma IgG at 12 hours of age compared to those fed unheated colostrum. Bull calves receiving heat-treated colostrum also had lower plasma BLG concentrations beginning at 6 hours of life. By 9 hours, those that received heat-treated colostrum had 51% less plasma BLG compared to bulls fed unheated colostrum. The BLG concentration decreased more rapidly from circulation than IgG. No significant differences in villus height or crypt depth were detected with regards to colostrum treatment. Calves that received heat-treated colostrum had a significantly higher number of goblet cells compared to those receiving unheated colostrum. In the second experiment, heifer calves were also analyzed for absorption of IgG and BLG into the blood. Average daily gain, grain intake, and daily rectal temperatures were recorded for each heifer until weaning. Despite being fed from the same pools of colostrum, heifer calves did not demonstrate the same absorption patterns for IgG and BLG as were seen with the bulls. Heifer calves receiving heat-treated colostrum had higher circulating IgG levels during the first 24 hours of life compared to those fed unheated colostrum. No significant differences in plasma BLG concentration, grain intake, or health scores were detected. Daily rectal temperatures also did not differ significantly during weeks 1, 2, 3, 4, and 6. However, during week 5, calves that had received heat-treated colostrum had significantly higher rectal temperatures compared to those fed unheated colostrum. Although no statistically significant differences were detected for average daily gain, during week 5, there was a tendency for heifers receiving heat-treated colostrum to have a lower rate of gain. Week 5 corresponds to when calves were dehorned. The results of the study indicate that heat-treatment of colostrum influences absorption, gut development and health of calves during the neonatal and pre-weaned periods of life.

• Subjects / Keywords

  • Calf
  • Dairy
  • Colostrum

• Graduation date

  Fall 2014

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3HH6CC7T

• 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.