Effects of Delayed and Extended Colostrum Feeding Strategies on Small Intestinal Growth in Neonatal Holstein Bull Calves

• Author / Creator

  Pyo, Jade

• Enhancing passive transfer of immunoglobulins (Ig) in calves has been the main focus of colostrum feeding in the dairy industry. Currently, it is not yet clear how the timing and extended duration of colostrum feeding impacts neonatal calf intestinal development. The aim of Study 1 was to determine how the timing of the first colostrum meal after birth (0, 6, or 12h delay) impacts the growth of the neonatal calf’s small intestine based on histological and ultrastructure analysis at 51 h of life (Chapter 2). Study 1 demonstrated that at 51 h of life, fetal enterocyte population was still evident. It also showed that calves fed colostrum later in their lives (6 h and 12 h) had larger intestinal surface area and villi height compared to calves receiving colostrum immediately after birth (0 h). However, growth factors such as insulin-like growth factor 1 and glucagon-like peptide 2 did not differ among the treatments. The unexpected growth response in 6 and 12 h treatments from study 1 may be explained in two ways: 1) compensatory growth and/or 2) residual colostrum trophic effect in 6 and 12 h calves. This study was not conclusive and led to more questions about the biological significance of the results so it is still recommended to feed the initial colostrum within the first hours of life to ensure the benefits of passive transfer. Study 2 examined the impact of extending colostrum feeding on intestinal structure and growth factor concentrations in blood (Chapter 3). Calves had the same initial colostrum feeding at 2 h of life, then were randomly assigned to one of three treatment groups: colostrum (COL), diet of 50% colostrum and 50% milk (MIX), or milk (MILK) from 12 h of life to 72 h of life. The results revealed that villi height was larger in COL and MIX calves compared to MILK calves, and surface area in the small intestine was larger in MIX calves than both COL and MILK calves. Proliferation in crypts of the ileum was also greater in MIX calves compared to MILK calves. Glucagon-like peptide 2 levels were higher in COL calves compared to MILK calves, while levels of insulin-like growth factor 1 tended to be larger in COL calves than in MILK calves. The reasons for the similar trophic response in MIX calves compared to COL calves are hypothesized to be: 1) saturation of the absorptive capacity of the enterocytes, 2) high amount of total solids of colostrum negatively affecting absorption, or 3) abrupt transition from the high energy diet to low energy diet affecting intestinal growth negatively. Based on the results from study 2, supplementing milk with colostrum is beneficial for neonatal calf intestinal growth.

• Subjects / Keywords

  • Calf
  • Colostrum
  • Early nutrition

• Graduation date

  Fall 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3QZ22Z9H

• License

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