Background: The goal of this study was to examine the response of the cyclic corpus luteum of cows to the administration of a prostaglandin F2α analogue (PGF) during the transition of refractoriness to responsiveness by investigating ultrasonographic changes in the corpus luteum and changes in plasma progesterone concentration in cows following the administration of PGF 3 and 5 days after ovulation.
Results: All cows that responded to PGF given on day 5 ovulated on day 9. In the cows that did not respond on day 5, the luteal cross-sectional area stagnated after treatment, whereas the plasma progesterone concentration continued to increase. In the cows that received PGF on day 3 of the oestrous cycle, the luteal cross-sectional area and the plasma progesterone concentration continued to increase.
Conclusions: The results of this study suggest that the transition of the bovine corpus luteum from refractoriness to responsiveness to PGF occurs during day 5 of the oestrous cycle because in 5 of 8 cows given PGF on day 5, early luteal regression was evident during the examination 24 hours after PGF administration.
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http://dx.doi.org/10.1186/1746-6148-8-220 | DOI Listing |
Anim Reprod Sci
January 2025
Agrotecnio Center, Department of Animal Sciences, University of Lleida, Lleida 25198, Spain.
The objectives of this study were: (i) to evaluate the associations between postpartum health disorders, relative increase in walking activity (RIWA) and expression of behavioral estrus intensity captured by pedometers; (ii) to assess associations between RIWA and pregnancy in cows submitted to timed artificial insemination (TAI). Lactating dairy cows (n = 881) were enrolled in the study. Cows were submitted to a 5d TAI protocol with insertion of a progesterone device.
View Article and Find Full Text PDFTheriogenology
January 2025
Department of Animal Sciences, University of Florida, Gainesville, FL, USA. Electronic address:
Implementing accelerometer technologies in beef operations is an alternative to increase precision in estrous detection. We hypothesized that (1) the accelerometer algorithm has similar accuracy in detecting behavioral estrus as does visual observation of pressure-sensitive sensors (estrus patches) in grazing beef cows; (2) variables measured by the accelerometer, such as estrus intensity, are associated with hormonal, ovarian, and uterine variables monitored before, during, and after estrus; and (3) the accelerometer variables are associated with the probability of pregnancy in grazing beef cows submitted to embryo transfer (ET). Fifty cows were fitted with accelerometer and patches to detect estrus after a synchronization protocol in eight subsequent rounds.
View Article and Find Full Text PDFBMJ Case Rep
January 2025
Obstetrics and Gynecology, All India Institute of Medical Sciences, New Delhi, India.
Von Willebrand's disease (vWD) is an inherited coagulopathy. In women, this condition can present as periovulatory intra-abdominal bleeding or bleeding from the corpus luteum. A diagnosed case of vWD presented as an emergency with nausea, acute abdominal pain and dizziness.
View Article and Find Full Text PDFJ Equine Vet Sci
January 2025
Equine Fertility Group, Faculty of Veterinary Medicine, Universidad Cardenal Herrera-CEU, CEU Universities, 46115 Alfara del Patriarca, Valencia, Spain; Broline International AB, 51293 Svenljunga, Sweden. Electronic address:
The objective of this study was to compare the fertility of diestrous mares with a follicle ≥ 30 mm in diameter treated with prostaglandin F2α (PGF) (PGF group) or left untreated for 7 days (SP group). Standardbred mares (n = 46) were assigned randomly to the SP (n = 23) and PGF groups (n = 23) when they were identified with a corpus luteum (CL) of unknown age and a follicle ≥ 30 mm in diameter (Day 0). The most frequent outcome in the PGF group was estrus and ovulation of the dominant follicle (74 %), while the outcomes of the SP mares 7 days after Day 0 were more variable: estrus and follicle regression (30 %), diestrous ovulation (22 %) and diestrus along with follicle regression (26 %) of the dominant follicles.
View Article and Find Full Text PDFAdv Anat Embryol Cell Biol
January 2025
Laboratory of Molecular Morphophysiology and Development, Department of Veterinary Medicine, School of Animal Science and Food Engineering, University of São Paulo, São Paulo, Brazil.
In this chapter, we explore the multifaceted roles of extracellular vesicles (EVs) in ovarian biology, focusing on their contributions to folliculogenesis, oocyte competence, corpus luteum function, and immune response regulation. EVs, particularly those derived from follicular fluid (ffEVs), are crucial mediators of cell-to-cell communication within the ovarian follicle, influencing processes such as meiotic progression, stress response, and hormonal regulation. We review preexisting literature, highlighting key findings on the molecular cargo of EVs, such as miRNAs and proteins, and their involvement in regulating the function of the follicle cells.
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