Symposium review: Linking activity-sensor data and physiology to improve dairy cow fertility.

Autor: Cerri RLA; Applied Animal Biology, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4. Electronic address: ronaldo.cerri@ubc.ca., Burnett TA; Applied Animal Biology, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4., Madureira AML; Applied Animal Biology, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4., Silper BF; Applied Animal Biology, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4., Denis-Robichaud J; Department of Population Medicine, University of Guelph, Guelph, ON, Canada, N1G 2W1., LeBlanc S; Department of Population Medicine, University of Guelph, Guelph, ON, Canada, N1G 2W1., Cooke RF; Department of Animal Science, College of Agriculture and Life Sciences, Texas A&M University, College Station 77843., Vasconcelos JLM; Department of Animal Production, Faculty of Veterinary Medicine and Animal Science, São Paulo State University, Botucatu, Brazil, 18160-000.
Jazyk: angličtina
Zdroj: Journal of dairy science [J Dairy Sci] 2021 Jan; Vol. 104 (1), pp. 1220-1231. Date of Electronic Publication: 2020 Nov 12.
DOI: 10.3168/jds.2019-17893
Abstrakt: Several studies have demonstrated that the intensity of estrous expression is associated with ovulation, ovarian and uterine function, and fertility, and is dependent on social hierarchy and the housing system used. Data from recent studies involving spontaneous and induced estrus have shown that a greater relative increase and longer estrus (captured by different automated activity monitors; AAM) are both associated with improved pregnancy per artificial insemination (AI; around 10 to 14% increase) and decreased pregnancy losses. Intensity and duration of estrus were surprisingly weakly associated with preovulatory follicle diameter and concentrations of plasma estradiol at estrus, whereas ovulation failure was associated with low estrus intensity. Studies have also shown that the display of estrous behavior near AI was associated with the modification of expression of genes related to the immune system, adhesion molecules, and prostaglandin synthesis in the endometrium. Transcripts in leukocytes and in the conceptus tissue associated with maternal recognition of pregnancy as well as conceptus elongation were all associated with differences in the intensity of estrous expression. Most recently, studies from the United States and Canada have demonstrated that reproductive programs emphasizing detection of estrus using AAM can be successful and comparable to intensive timed AI protocol-based programs that incorporate GnRH and PGF 2α treatments. Further, one study concluded that the administration of GnRH at AI for spontaneous estrus events greatly improved pregnancy per AI, but only for cows with reduced intensity of estrous expression, showing the potential to use AAM data as a tool in targeted reproductive programs. Quantitative information from estrus events could be used to improve estrus detection and develop decision-making strategies at the farm level. Future studies in this field should aim to better understand ovarian, conceptus, and endometrial mechanisms associated with either the expression or the intensity of estrus, and to refine the identification of phenotypes related to estrus (relative increase, absolute increase, baseline levels, duration, and repeatability within cow) to improve data usage, estrus detection, and possibly genetic selection.
(Copyright © 2021 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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