The impact of plasma concentrations of progesterone during superovulation on estrous behaviour, and ovarian and early embryonic development in Holstein heifers
department or school: Land and Food Systems, Faculty of
data provider: DSpace
degree campus: UBCV
creator: dos Santos Marques, Jessica Cristina
issued: 2022-09-09T16:23:36Z
issued: 2022
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Greater progesterone (P4) levels prior to and post estrus in lactating dairy cows has been associated with improved fertility and greater intensity of estrous expression measured by automated activity monitors (AAM). Recently, greater intensity of estrous expression has also been associated with greater embryo production and quality in superovulated dairy heifers. However, it is unclear whether P4 causes greater expression of estrus and increased early embryo development in superovulated heifers. Therefore, the aim of this thesis was to evaluate the effect of different P4 concentrations in plasma during the follicular growth on the intensity of estrous expression, ovarian response to the superovulatory treatment, and embryo production and quality in superovulated Holstein heifers. In Chapter 1, scientific studies are reviewed to highlight gaps in the literature associated with P4 regulation, intensity of estrous expression and reproductive outcomes in dairy cattle. In Chapter 2, I found that different P4 levels during the follicular growth did not affect the maximum intensity of estrous expression or the duration of estrus in superovulated Holstein heifers. However, high P4 concentrations in plasma during the development of follicles increased embryo quality and reduced the number of embryos produced when compared to low P4 concentrations. Although estrous expression did not relate to the quality of embryos, the duration of estrus and the maximum intensity of estrous expression increased the number of embryos recovered 7 d post artificial insemination. In Chapter 3, study limitations and future directions are summarized. In conclusion, my results suggest that P4 concentrations during the follicular growth, and intensity of estrous expression, are important in regulating the quality of embryos and the number of embryos produced by superovulated heifers.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/82681
note: THE IMPACT OF PLASMA CONCENTRATIONS OF PROGESTERONE DURING SUPEROVULATION ON ESTROUS BEHAVIOUR, AND OVARIAN AND EARLY EMBRYONIC DEVELOPMENT IN HOLSTEIN HEIFERS by Jessica Cristina dos Santos Marques Techn., Agricultural Technical College "Jose Bonifacio", 2013 DVM., Federal University of Uberlandia, 2020 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Applied Animal Biology) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) September 2022 © Jessica Cristina dos Santos Marques, 2022 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, a thesis entitled: The impact of plasma concentrations of progesterone during superovulation on estrous behaviour, and ovarian and early embryonic development in Holstein heifers. submitted by Jessica Cristina dos Santos Marques in partial fulfillment of the requirements for the degree of Master of Science in Applied Animal Biology Examining Committee: Dr. Ronaldo L.A. Cerri, Associate Professor, Applied Animal Biology, UBC Supervisor Dr. Alexandra Protopopova, Assistant Professor, Applied Animal Biology, UBC Supervisory Committee Member Dr. Alexander G. Beristain, Associate Professor, Obstetrics and Gynaecology, UBC Supervisory Committee Member Dr. Barbara Stefanska, Assistant Professor, Food, Nutrition and Health, UBC Additional Examiner Additional Supervisory Committee Members: Dr. Daniel Weary, Professor, Applied Animal Biology, UBC Supervisory Committee Member iii Abstract Greater progesterone (P4) levels prior to and post estrus in lactating dairy cows has been associated with improved fertility and greater intensity of estrous expression measured by automated activity monitors (AAM). Recently, greater intensity of estrous expression has also been associated with greater embryo production and quality in superovulated dairy heifers. However, it is …
has type: Thesis/Dissertation
date issued: 2022-11
is shown at: 10.14288/1.0419310
language: eng
degree discipline: Applied Animal Biology
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Cerri, Ronaldo
type: Text
identifier URI: http://hdl.handle.net/2429/82681