scholarly journals Effect of eCG on the follicular dynamics and vascularization of crossbred cows with different circulating progesterone concentrations during synchronization of ovulation in an FTAI protocol

2019 ◽  
Vol 39 (5) ◽  
pp. 324-331 ◽  
Author(s):  
Priscila A. Ferraz ◽  
Mariana A.A. Silva ◽  
Bia S.S. Carôso ◽  
Endrigo A.B. Araujo ◽  
Thereza C.B.S.C. Bittencourt ◽  
...  
Keyword(s):  
Power Doppler ◽  
Fixed Time ◽  
High Plasma ◽  
Preovulatory Follicle ◽  
Crossbred Cows ◽  
Follicle Diameter ◽  
Dynamics And Function ◽  
And Function ◽  
Synchronization Protocol ◽  
Follicular Dynamics

ABSTRACT: This study aimed to evaluate the effect of treatment with equine chorionic gonadotrophin (eCG) on the follicular dynamics and function of crossbred cows with different circulating progesterone (P4) concentrations during synchronization of ovulation in a fixed-time artificial insemination (FTAI) protocol. To this end, 30 crossbred cows were submitted to a pre-synchronization protocol to ensure that all of them presented corpus luteum (CL) at the beginning of the protocol, and were evaluated by transrectal ultrasonography (TRUS) to verify the presence of CL. After that, the animals underwent an ovulation synchronization protocol and evaluation of follicular dynamics and vascularization by B-mode and power-Doppler ultrasound (US). High plasma P4 concentrations at the time of ovulation synchronization negatively influenced follicle diameter on day 10 (D10), preovulatory follicle diameter, and preovulatory follicle wall vascularization area (p<0.05). Cows with high P4 concentration at the time of ovulation synchronization that were treated with eCG showed follicle diameter on D10 and preovulatory follicle diameter and wall vascularization area (p>0.05) similar to those of animals with low P4 concentration at the time of ovulation synchronization. Therefore, high P4 concentrations at the time of ovulation synchronization negatively influence follicular diameter and vascularization, and eCG can be used as a strategy to favor better follicular and luteal response in crossbred cows with high P4 concentrations submitted to an FTAI protocol.

124 RELATIONSHIPS BETWEEN PREOVULATORY FOLLICLE AND CORPUS LUTEUM BLOOD FLOW IN MARES

2012 ◽  
Vol 24 (1) ◽  
pp. 174
Author(s):  
A. Wischral ◽  
K. T. Haag ◽  
G. R. Fonseca ◽  
M. O. Gastal ◽  
S. S. King ◽  
...  
Keyword(s):  
Blood Flow ◽  
Doppler Ultrasonography ◽  
New Technologies ◽  
Power Doppler ◽  
Corpora Lutea ◽  
Power Doppler Ultrasonography ◽  
Preovulatory Follicle ◽  
Vascular Perfusion ◽  
Follicle Diameter ◽  
Student’S T

Colour- and power-Doppler ultrasonography have recently been used as potential new technologies to assess the degree of vascular perfusion of the ovary and follicles for research and clinical studies of ovarian and follicle hemodynamics and to predict fertility in horses, cattle and humans. In the present study, the following hypotheses were tested: (1) preovulatory follicle (POF) diameter (≥30 mm), but not blood flow, is repeatable between cycles within the same mare; (2) POF diameter and blood flow are good indicators of follicle status; (3) double POF have similar blood flow; and (4) highly vascularized POF produce corpora lutea (CL) with greater blood flow. Non-lactating mares (n = 13; 5 to 21 years old) of mixed breeds were used from March to May in the Northern Hemisphere. Follicle diameter and vascularity of the follicle wall before the first and second ovulations of the season and vascularity of the first CL were measured daily using transrectal colour-Doppler ultrasonography. The vascularity of the follicle wall and CL was based on the display of the blood-flow signals visualised in a slow, continuous-motion evaluation. Statistical analyses were performed by the SAS MIXED procedure, ANOVA and Student's t-tests and Spearman's correlation. A total of 26 periovulatory periods were evaluated. Unexpectedly, there were 84.6% (11/13) and 61.5% (8/13) double dominant POF and 30.8% (4/13) and 46.2% (6/13) double ovulations in the first and second periovulatory periods, respectively. The POF diameters were highly correlated (r = 0.68; P < 0.0001) between the first and second periovulatory periods. The diameter of the POF 5 days before the first ovulation was larger (P < 0.004) than before the second ovulation of the year. However, the POF vascularity did not differ between those periods. For 4 days before ovulation (Day 0), the diameter and blood flow of the POF were greater (P < 0.05) than for those follicles that underwent atresia in single- and double-ovulatory mares. The POF diameter and blood flow were positively correlated in ovulatory (r = 0.51; P < 0.0001) and in atretic (r = 0.32; P < 0.02) follicles. In double-ovulatory mares, POF diameter and blood flow increased (P < 0.0006) for 5 days before ovulation, with no difference between the 2 follicles in the same cycle for each parameter. The POF blood flow was positively correlated (r = 0.32; P < 0.0009) with CL vascularity during the first periovulatory period (Day –7 to +6) of the season. Furthermore, a positive correlation (r = 0.58; P < 0.01) was observed between the maximum vascularity of the POF and its subsequent CL. In conclusion, although preliminary, our results demonstrated that (a) POF vascularity is not repeatable within individuals; (b) potential atretic POF have low blood flow; (c) double POF have similar vascularity; and (d) greater blood flow to the POF is associated with higher CL vascularity.

Effects of presynchronization and eCG on pregnancy rates to GnRH-based, fixed-time artificial insemination in beef heifers

2010 ◽  
Vol 90 (1) ◽  
pp. 23-34 ◽  
Author(s):  
J A Small ◽  
M G Colazo ◽  
J P Kastelic ◽  
N E Erickson ◽  
R J Mapletoft
Keyword(s):  
Chorionic Gonadotropin ◽  
Artificial Insemination ◽  
Follicular Development ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Preovulatory Follicle ◽  
Beef Heifers ◽  
Plasma Progesterone ◽  
Follicle Diameter ◽  
Equine Chorionic Gonadotropin

Three experiments were conducted to determine the effects of presynchronization and treatment with equine chorionic gonadotropin (eCG) on corpus luteum (CL) and ovarian follicular development, plasma progesterone concentrations, and pregnancy rates in beef heifers subjected to a gonadotropin releasing hormone (GnRH)-based, fixed-timed AI (TAI) protocol. All heifers were given GnRH on day 0, prostaglandin F2α (PGF) on day 7, and a second GnRH on day 9 concurrent with TAI (54 h after PGF). In exp. 1 (N = 148), presynchronization with PGF (days -22 and -11) decreased the percentage of heifers with non-luteal plasma progesterone concentrations on day 0 (5.4 vs 29.7%) and day 7 (0 vs 11.6%; P < 0.05), but not on day 9 (74.3 vs. 66.2%; P > 0.20), and reduced the number of heifers in estrus and bred before TAI (P < 0.05). Although presynchronization reduced preovulatory follicle diameter (12.9 ± 0.3 vs. 14.9 ± 0.3 mm; mean ± SEM; P < 0.01), it did not affect TAI pregnancy rates (36.5 vs. 29.7%; P > 0.20). In exp. 2, heifers (N = 128) were presynchronized with melengestrol acetate (MGA) (days -27 to -12), and received a controlled internal drug release (CIDR) on day 0; on day 7, half were given 300 IU of eCG at CIDR removal. Treatment with eCG tended to increase preovulatory follicle diameter in heifers that did not ovulate to GnRH on day 0 (P = 0.06), but did not affect the percentage of heifers with non-luteal plasma progesterone concentrations on day 9 (57.8 vs. 57.8%) or TAI pregnancy rates (48.4 vs. 53.1%; P > 0.20). Experiment 3 was a 2 × 2 factorial arrangement of presynchronization (PGF concurrent with a CIDR on day -7) and eCG treatments (on day 7) applied to heifers in three herds (A, N = 150, B, N = 260 and C, N = 40). All heifers had a once-used CIDR from days 0 to 7. Presynchronization increased the percentage of heifers (Herd A) with low-luteal plasma progesterone concentrations on day 0 (70.7 vs. 22.7%) and day 7 (90.7 vs. 53.3%; P < 0.01), but did not affect the percentage of heifers with non-luteal concentrations of progesterone on day 9 (97.3 vs. 93.3%; P > 0.20). Combined for all herds, presynchronization reduced the prevalence of a CL on day 0 (23.5 vs. 73.7%; P < 0.01), and increased the prevalence of follicles ≥ 10 mm on day 7 (96.8 vs. 86.7%; P < 0.01); however, TAI pregnancy rates (195/439 = 44.4%) were not improved by either presynchronization or eCG treatment (P > 0.20).Key words: Presynchronization, equine chorionic gonadotropin, GnRH, fixed-time artificial insemination, progesterone

scholarly journals Impact of exogenous progesterone on ovarian follicular dynamics and function in mice

Reproduction ◽  
1991 ◽  
Vol 93 (2) ◽  
pp. 263-269 ◽  
Author(s):  
E. Telfer ◽  
R. G. Gosden ◽  
M. J. Faddy
Keyword(s):  
Exogenous Progesterone ◽  
Dynamics And Function ◽  
And Function ◽  
Follicular Dynamics

Temporal relationships of the LH surge and ovulation to echotexture and power Doppler signals of blood flow in the wall of the preovulatory follicle in heifers

2010 ◽  
Vol 22 (7) ◽  
pp. 1110 ◽  
Author(s):  
M. A. R. Siddiqui ◽  
J. C. Ferreira ◽  
E. L. Gastal ◽  
M. A. Beg ◽  
D. A. Cooper ◽  
...  
Keyword(s):  
Blood Flow ◽  
Power Doppler ◽  
Initial Increase ◽  
Preovulatory Follicle ◽  
Lh Surge ◽  
Follicle Diameter ◽  
Temporal Relationships ◽  
Preovulatory Follicles ◽  
Doppler Signals ◽  
Gonadotrophin Releasing Hormone

Changes in echotexture and blood flow in the wall of preovulatory follicles in heifers were studied in relation to the LH surge and ovulation in gonadotrophin-releasing hormone-induced (n = 7; Experiment 1) and spontaneous (n = 8; Experiment 2) ovulators. Ultrasonographic examinations and blood sampling were performed either every hour (Experiment 1) or every 6 h (Experiment 2). The interval from LH peak to ovulation in induced and spontaneous ovulators was 27.1 ± 0.3 and 34.5 ± 1.5 h, respectively. Follicle diameter did not increase between the LH peak and ovulation. In the induced ovulators, serration of the stratum granulosum was detected in one (14%), two (29%), three (43%) and four (57%) heifers at 4, 3, 2 and 1 h before ovulation, respectively. An initial increase in blood flow (P < 0.001) encompassed the LH peak in both experiments. In the induced ovulators, blood flow increased (P < 0.02) to maximum 3 h after the LH peak, maintained a plateau for 5 h, decreased (P < 0.05) between 9 and 14 h, increased (P < 0.05) again between 19 and 21 h and then decreased (P < 0.01) between 25 and 26 h (1 h before ovulation). The biphasic increase and decrease in blood flow and serration of the granulosum in the wall of the preovulatory follicle in cattle are novel findings.

scholarly journals Exploring the microbiome in health and disease

2017 ◽  
Vol 1 ◽  
pp. 239784731774188 ◽  
Author(s):  
Elena Scotti ◽  
Stéphanie Boué ◽  
Giuseppe Lo Sasso ◽  
Filippo Zanetti ◽  
Vincenzo Belcastro ◽  
...  
Keyword(s):  
Human Health ◽  
Metabolic Diseases ◽  
Skin Diseases ◽  
Human Microbiome ◽  
Chronic Obstructive ◽  
Microbial Composition ◽  
Obstructive Pulmonary Disease ◽  
New Findings ◽  
Dynamics And Function ◽  
And Function

The analysis of human microbiome is an exciting and rapidly expanding field of research. In the past decade, the biological relevance of the microbiome for human health has become evident. Microbiome comprises a complex collection of microorganisms, with their genes and metabolites, colonizing different body niches. It is now well known that the microbiome interacts with its host, assisting in the bioconversion of nutrients and detoxification, supporting immunity, protecting against pathogenic microbes, and maintaining health. Remarkable new findings showed that our microbiome not only primarily affects the health and function of the gastrointestinal tract but also has a strong influence on general body health through its close interaction with the nervous system and the lung. Therefore, a perfect and sensitive balanced interaction of microbes with the host is required for a healthy body. In fact, growing evidence suggests that the dynamics and function of the indigenous microbiota can be influenced by many factors, including genetics, diet, age, and toxicological agents like cigarette smoke, environmental contaminants, and drugs. The disruption of this balance, that is called dysbiosis, is associated with a plethora of diseases, including metabolic diseases, inflammatory bowel disease, chronic obstructive pulmonary disease, periodontitis, skin diseases, and neurological disorders. The importance of the host microbiome for the human health has also led to the emergence of novel therapeutic approaches focused on the intentional manipulation of the microbiota, either by restoring missing functions or eliminating harmful roles. In the present review, we outline recent studies devoted to elucidate not only the role of microbiome in health conditions and the possible link with various types of diseases but also the influence of various toxicological factors on the microbial composition and function.

scholarly journals Critical requirement of SOS1 RAS-GEF function for mitochondrial dynamics, metabolism, and redox homeostasis

Oncogene ◽  
2021 ◽  
Author(s):  
Rósula García-Navas ◽  
Pilar Liceras-Boillos ◽  
Carmela Gómez ◽  
Fernando C. Baltanás ◽  
Nuria Calzada ◽  
...  
Keyword(s):  
Mitochondrial Dynamics ◽  
Redox Homeostasis ◽  
Atp Production ◽  
Oxidative Energy Metabolism ◽  
Ras Activation ◽  
Mitochondrial Defects ◽  
Critical Requirement ◽  
Dynamics And Function ◽  
And Function ◽  
And Control

AbstractSOS1 ablation causes specific defective phenotypes in MEFs including increased levels of intracellular ROS. We showed that the mitochondria-targeted antioxidant MitoTEMPO restores normal endogenous ROS levels, suggesting predominant involvement of mitochondria in generation of this defective SOS1-dependent phenotype. The absence of SOS1 caused specific alterations of mitochondrial shape, mass, and dynamics accompanied by higher percentage of dysfunctional mitochondria and lower rates of electron transport in comparison to WT or SOS2-KO counterparts. SOS1-deficient MEFs also exhibited specific alterations of respiratory complexes and their assembly into mitochondrial supercomplexes and consistently reduced rates of respiration, glycolysis, and ATP production, together with distinctive patterns of substrate preference for oxidative energy metabolism and dependence on glucose for survival. RASless cells showed defective respiratory/metabolic phenotypes reminiscent of those of SOS1-deficient MEFs, suggesting that the mitochondrial defects of these cells are mechanistically linked to the absence of SOS1-GEF activity on cellular RAS targets. Our observations provide a direct mechanistic link between SOS1 and control of cellular oxidative stress and suggest that SOS1-mediated RAS activation is required for correct mitochondrial dynamics and function.

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