Defining the gonadotrophin requirement for the selection of a single dominant follicle in cattle

2020 ◽  
Vol 32 (3) ◽  
pp. 322 ◽  
Author(s):  
Jin G. Gong ◽  
Bruce K. Campbell ◽  
Robert Webb
Keyword(s):  
Major Effect ◽  
Follicle Development ◽  
Preovulatory Follicle ◽  
Ultrasound Scanning ◽  
Dominant Follicle ◽  
Initial Exposure ◽  
Preovulatory Follicles ◽  
Gonadotrophin Releasing Hormone ◽  
Follicular Response ◽  
Selection Of

The aim was to define the pattern and physiological concentrations of FSH and LH required for the selection of a single dominant follicle in mono-ovulatory species. A series of five experiments was carried out using gonadotrophin-releasing hormone agonist-induced hypogonadal heifers. Animals were infused with different patterns of either FSH and/or LH followed by an ovulatory dose of human chorionic gonadotrophin. Follicular response was monitored by ultrasound scanning and blood samples were collected to measure concentrations of FSH, LH, oestradiol and progesterone. The main findings were: (1) physiological concentrations of FSH given as a continuous infusion and for an adequate duration, in the presence of basal LH, with or without LH pulses, are capable of inducing a superovulatory response, (2) initial exposure to FSH followed by LH pulses alone stimulate the development of multiple preovulatory follicles, confirming that ovarian follicles are capable of transferring dependence on gonadotrophins from FSH to LH, (3) while LH pulses appear not to have a major effect on the pattern of preovulatory follicle development, adequate LH pulsatile support is required for full oestradiol synthesis and (4) the duration of initial exposure to FSH and the ability to transfer the dependence from FSH to LH are critical for the selection of a single dominant follicle. In conclusion, this experimental series confirms that the duration of initial exposure to FSH and the ability of the selected follicle to transfer its gonadotrophic dependence from FSH to LH are critical for the selection of a single dominant follicle in cattle.

The use of GNRH to control follicular development in cows

1996 ◽  
Vol 1996 ◽  
pp. 95-95
Author(s):  
A.R. Peters ◽  
S.J. Ward ◽  
P.J. Gordon ◽  
G.E. Mann
Keyword(s):  
Dairy Cows ◽  
Present Experiment ◽  
Luteal Phase ◽  
Ovarian Function ◽  
Steroid Hormone ◽  
Follicular Development ◽  
Follicle Development ◽  
Preovulatory Follicle ◽  
Hormone Production ◽  
Gonadotrophin Releasing Hormone

Fertility after prostaglandin (PG) may be compromised by the variability in timing of oestrus and ovulation, which are in turn influenced by the ovarian follicular status at the time of injection. Gonadotrophin-releasing hormone (GnRH) treatment in the luteal phase a few days before PG can reprogramme and thus synchronise preovulatory follicle development (Wolfenson et al., 1994). A second GnRH treatment can then be given after PG, to further improve the synchrony of ovulation (Pursley et al., 1995). The present experiment was carried out to test the effect of this combined GnRH - PG - GnRH regime on ovarian function and steroid hormone production in dairy cows.

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 Effect of the metabolic environment at key stages of follicle development in cattle: focus on steroid biosynthesis

2012 ◽  
Vol 44 (9) ◽  
pp. 504-517 ◽  
Author(s):  
S. W. Walsh ◽  
J. P. Mehta ◽  
P. A. McGettigan ◽  
J. A. Browne ◽  
N. Forde ◽  
...  
Keyword(s):  
Luteal Phase ◽  
Ovarian Follicle ◽  
Regulatory Protein ◽  
Follicle Development ◽  
Preovulatory Follicle ◽  
Dominant Follicle ◽  
Beef Heifers ◽  
Steroid Biosynthesis ◽  
Lh Surge ◽  
Lactating Cows

Cellular mechanisms that contribute to low estradiol concentrations produced by the preovulatory ovarian follicle in cattle with a compromised metabolic status are largely unknown. To gain insight into the main metabolic mechanisms affecting preovulatory follicle function, two different animal models were used. Experiment 1 compared Holstein-Friesian nonlactating heifers ( n = 17) and lactating cows ( n = 16) at three stages of preovulatory follicle development: 1) newly selected dominant follicle in the luteal phase (Selection), 2) follicular phase before the LH surge (Differentiation), and 3) preovulatory phase after the LH surge (Luteinization). Experiment 2 compared newly selected dominant follicles in the luteal phase in beef heifers fed a diet of 1.2 times maintenance (M, n = 8) or 0.4 M ( n = 11). Lactating cows and 0.4 M beef heifers had higher concentrations of β-hydroxybutyrate, and lower concentrations of glucose, insulin, and IGF-I compared with dairy heifers and 1.2 M beef heifers, respectively. In lactating cows this altered metabolic environment was associated with reduced dominant follicle estradiol and progesterone synthesis during Differentiation and Luteinization, respectively, and in 0.4 M beef heifers with reduced dominant follicle estradiol synthesis. Using a combination of RNA sequencing, Ingenuity Pathway Analysis, and qRT-PCR validation, we identified several important molecular markers involved in steroid biosynthesis, such as the expression of steroidogenic acute regulatory protein ( STAR) within developing dominant follicles, to be downregulated by the catabolic state. Based on this, we propose that the adverse metabolic environment caused by lactation or nutritional restriction decreases preovulatory follicle function mainly by affecting cholesterol transport into the mitochondria to initiate steroidogenesis.

scholarly journals Corpus luteum development and its morphology after aspiration of a preovulatory follicle is related to size and steroid content of the follicle in dairy cows

2013 ◽  
Vol 58 (No. 4) ◽  
pp. 221-229 ◽  
Author(s):  
A. Vernunft ◽  
JM Weitzel ◽  
T. Viergutz
Keyword(s):  
Dairy Cows ◽  
Corpus Luteum ◽  
Cross Section ◽  
Preovulatory Follicle ◽  
Dominant Follicle ◽  
Cross Section Area ◽  
Section Area ◽  
Preovulatory Follicles ◽  
Luteal Tissue ◽  
Follicle Aspiration

Secretion of adequate levels of progesterone from a proper corpus luteum (CL), which develops out of the cells of a healthy preovulatory follicle, is a key-factor for establishment of a pregnancy. The aim of this study was to investigate the relationship between morphological and secretory characteristics of preovulatory follicles and their corresponding corpus luteum with regard to the post-partum period in high-yielding dairy cows. Therefore, ultrasound-guided aspirations of preovulatory follicles were performed repeatedly, using 20 first lactating cows between 26 and 121 days after parturition. Heat was induced with a PGF analogon followed by administration of a GnRH analogon. The dominant follicle was aspirated 21 h after administration of the GnRH analogon. The diameters of the follicles were estimated at aspiration and the morphology of the resulting luteal tissue was examined on day 14 after follicle aspiration using ultrasonographic examinations. Concentrations of progesterone (P<sub>4</sub>) and 17-beta-oestradiol (E<sub>2</sub>) were determined in the follicular fluids (FF) and P<sub>4</sub> concentration was estimated at the time of CL examination in plasma. A CL development occurred in 82% after dominant follicle aspiration. The interval of time between parturition and follicle aspiration did not affect the investigated variables. The diameter of the aspirated preovulatory follicle was positively correlated to the cross-section area of the developed luteal tissue (R = 0.60; P &lt; 0.01) as well as to the plasma P<sub>4</sub> concentration on day 14 after follicle aspiration (R = 0.47; P&nbsp;&lt; 0.05). Also, E<sub>2</sub> concentrations in FF were positively correlated to cross-section area of the luteal tissue (R = 0.54; P &lt; 0.05). Comparing the FF of the follicles that gave rise to a CL after aspiration to follicles that did not, both types had comparable P<sub>4</sub>, but the former type harboured higher E<sub>2</sub> concentrations. In conclusion, preovulatory follicle diameter as well as steroid concentrations in the follicular fluid could be used prospectively to identify cows which will have well-developed CLs and high plasma P<sub>4</sub> levels later. On the other hand, CL development after follicle aspiration can be used as a retrospective quality parameter of dominant follicles. These results will help to identify suitable animals for breeding or recipients for embryo transfer.&nbsp;&nbsp;&nbsp; &nbsp;

scholarly journals 323 THE QUALITY OF PREOVULATORY FOLLICLES DURING FINAL MATURATION IN COWS STIMULATED WITH oFSH AND A DEFINED LH SURGE

2005 ◽  
Vol 17 (2) ◽  
pp. 312
Author(s):  
O. Algriany ◽  
P. Vos ◽  
H. Groenendaal ◽  
A. van Gastel ◽  
B. Colenbrander ◽  
...  
Keyword(s):  
Follicular Development ◽  
High Variability ◽  
Dominant Follicle ◽  
Ultrasound Guided ◽  
Developmental Potential ◽  
Lh Surge ◽  
Final Maturation ◽  
Preovulatory Follicles ◽  
Selection Of

Multiple preovulatory follicles developing upon superovulation (SO) are heterogeneous in quality, which may be the consequence of follicular development deviating from that in untreated cyclic cows. Therefore, we investigated follicle performance in terms of estradiol (E), progesterone (P), and testosterone (T) concentrations in the fluid of stimulated preovulatory follicles (FF), in particular at onset of final maturation as initiated by the LH surge. Pre-synchronized HF cows (n = 25) were treated with oFSH (Ovagen; ICP, Auckland, New Zealand) for SO, and FF were collected 2 h pre-LH surge (n = 9 cows), and 6 h (n = 8) and 22 h C(n = 8) post-LH. At Day 9 (estrus = Day 0), a norgestomet ear implant (Crestar; Intervet International BV, Boxmeer, The Netherlands) was inserted, and SO treatment was started at Day 10 using oFSH i.m. twice daily in decreasing doses during 4 days (total dose 17 mL). Prostaglandin (22.5 mg PG; Prosolvin, Intervet) was administered i.m. concomitant with the 5th dose of FSH. Ear implants were removed 50 h after PG and then GnRH (0.021 mg Receptal; Intervet) was administered i.m. inducing the LH surge 2 h later. Ovaries were collected by laparotomy at the time of GnRH, and 8 and 24 h later and all follicles sized >10 and <16 mm were aspirated to collect FF (pre-LH, n = 79; 6 h post-LH, n = 78; and 22 h post LH, n = 78 follicles). For comparison, E and P in FF from pre-LH groups that had been collected previously in 2 other experiments of our group were studied: (1)86 FF collected by ultrasound-guided aspiration of follicles >8 mm from 23 cows at 30 h after PG, that is, preceding the LH surge, following treatment with 3000 IU eCG i.m. (Folligon; Intervet) on Day 10 and 15 mg PG on Day 12; (2) 12 FF of the dominant follicle from 12 untreated cyclic cows after ovariectomy 48 to 62 h after onset of luteolysis, that is, shortly before the natural LH surge. The concentrations (ng/mL FF) of E, P, and T were estimated by our validated RIAs. Data (mean ± SEM) were analyzed by ANOVA. The levels of E, P and T of the oFSH group were pre-LH: 399 ± 35, 49 ± 6 and 13 ± 2; 6 h post-LH: 194 ± 11, 202 ± 12, and 14 ± 1; and 22 h post-LH: 35 ± 2, 200 ± 23, and 7 ± 1, respectively. Although the change in E and P levels between the different time points after LH is in agreement with that reported for untreated cyclic cows (Dieleman et al. 1983 J.Endocrinol. 97, 31–42), the concentrations were lower. However, the most striking finding was the significantly lower E in pre-LH FF after oFSH compared to that after eCG (1302 ± 82) or of cyclic cows (1942 ± 200). The P levels in FF of the respective pre-LH groups were not significantly different. The much lower E level after oFSH is possibly due to the low or even absent LH bioactivity for oFSH in comparison to eCG. It could also indicate a lower developmental potential of oocytes following oFSH. However, it is known that SO with oFSH results in regular yields of transferable embryos similar to that after eCG. In view of the high variability of the E level in FF, it is concluded that selection of follicles for high E levels is a prerequisite when investigating oocyte development and maturation.

176 BLOOD FLOW TO THE CORPUS LUTEUM AND PREOVULATORY FOLLICLE AFTER OVULATION INDUCTION DURING FIRST VERSUS SECOND WAVE IN WATER BUFFALO

2015 ◽  
Vol 27 (1) ◽  
pp. 179
Author(s):  
S. Caunce ◽  
D. Dadarwal ◽  
P. S. Brar ◽  
J. Singh
Keyword(s):  
Blood Flow ◽  
Corpus Luteum ◽  
Prostaglandin F2α ◽  
Preovulatory Follicle ◽  
Dominant Follicle ◽  
Flow Area ◽  
Vascular Area ◽  
Preovulatory Follicles ◽  
Luteal Tissue ◽  
Second Wave

The objective of the study was to compare the blood flow to the corpus luteum (CL) and the preovulatory follicle in dairy buffalo (Bubalus bubalis) when ovulation was induced during the first (low to increasing progesterone levels) versus the second (luteal progesterone levels) follicular wave. We hypothesised that the wall of the first-wave dominant follicle will be less vascular compared with that of the second-wave follicle. The study was conducted during the summer months in Punjab, India. Ovulation was synchronized with prostaglandin F2α (PGF) IM followed by gonadotropin-releasing hormone (GnRH) IM 48 h later (Day 0) and buffaloes were randomised to first wave (FW; n = 6) and second wave (SW; n = 7) groups. FW group was given PGF on Days 6.5 and 7, and GnRH on Day 9.5 followed by AI (14–16 h after GnRH). The SW group was given GnRH on Day 7 (to induce ovulation of first-wave dominant follicle without luteolysis and synchronous emergence of next wave), PGF on Days 13.5 and 14, GnRH on Day 16.5 followed by artificial insemination. Transrectal colour Doppler ultrasonography (MyLab5 Vetwith 7.5 MHz transducer, Esaote S.p.A, Genoa, Italy) was performed daily and 20-s cineloops of each ovary were recorded under standardized gain controls. Images from the cineloops were processed using Fiji (ImageJ, National Institutes of Health, Bethesda, MD, USA) to calculate the area of blood flow (coloured area = vascular area, grey scale area = tissue area, and their ratio) for the preovulatory follicle (on the day before ovulation) and luteal tissue (on the day of PGF injection and 4 days post-ovulation). Data were analysed by t-test from the animals that ovulated one day before (n = 3) or the day of AI (n = 6) and had a functional CL at day 5 post-AI (FW n = 5, SW n = 4). FW follicles ovulated on 8.6 ± 0.3 days from wave emergence compared with SW follicles on 10.0 ± 0.6 days (P < 0.05) but were similar in size (i.e. follicular area on the day before ovulation did not differ between groups; P = 0.5). There was no difference in the blood flow area in the wall of preovulatory follicles (P = 0.4). Vascular area of follicles was strongly correlated with their diameter (r = 0.87). Follicles >13.5 mm in diameter had more blood flow in their wall than smaller follicles (P < 0.01). FW had a tendency (P = 0.07) for smaller luteal area on the day of PGF treatment (FW = 171 ± 24 mm2; SW = 332 ± 81 mm2) and tended (P = 0.06) to have less vascular area in the CL compared to SW group (FW = 30 ± 6 mm2; SW = 67 ± 17 mm2). There was no difference (P = 0.5) between the groups for vascular to CL area ratio. The area of luteal tissue and blood flow to the CL at Day 4 post-ovulation did not differ between the groups (P = 0.4). The diameter of the preovulatory follicle (11.6–15.7 mm) was not correlated with the cross-sectional area of developing CL at Day 4 post-ovulation (r = 0.09). In conclusion, vascularity to preovulatory follicles originating from the first wave v. second wave did not differ and preovulatory follicles ≥13.5 mm were more vascular than smaller follicles. Research was funded by NSERC; the first author was funded by scholarships from WCVM and GADVASU.

The use of GNRH to control follicular development in cows

1996 ◽  
Vol 1996 ◽  
pp. 95-95
Author(s):  
A.R. Peters ◽  
S.J. Ward ◽  
P.J. Gordon ◽  
G.E. Mann
Keyword(s):  
Dairy Cows ◽  
Present Experiment ◽  
Luteal Phase ◽  
Ovarian Function ◽  
Steroid Hormone ◽  
Follicular Development ◽  
Follicle Development ◽  
Preovulatory Follicle ◽  
Hormone Production ◽  
Gonadotrophin Releasing Hormone

Fertility after prostaglandin (PG) may be compromised by the variability in timing of oestrus and ovulation, which are in turn influenced by the ovarian follicular status at the time of injection. Gonadotrophin-releasing hormone (GnRH) treatment in the luteal phase a few days before PG can reprogramme and thus synchronise preovulatory follicle development (Wolfenson et al., 1994). A second GnRH treatment can then be given after PG, to further improve the synchrony of ovulation (Pursley et al., 1995). The present experiment was carried out to test the effect of this combined GnRH - PG - GnRH regime on ovarian function and steroid hormone production in dairy cows.

Effects of gonadotrophin releasing hormone agonist treatment on oestrous cycle length and superovulatory response in maiden heifers

1995 ◽  
Vol 1995 ◽  
pp. 141-141
Author(s):  
L M Birnie ◽  
P J Broadbent ◽  
J S M Hutchinson ◽  
R G Watt ◽  
D F Dolman
Keyword(s):  
Luteinising Hormone ◽  
Antral Follicle ◽  
Follicle Development ◽  
Dominant Follicle ◽  
Releasing Hormone ◽  
Antral Follicles ◽  
Large Numbers ◽  
Pulsatile Administration ◽  
Gonadotrophin Releasing Hormone ◽  
Lh Secretion

Current variability in superovulatory response prevents the economical production of large numbers of high quality embryos and limits the use of embryo transfer. Pulsatile administration of GnRH (gonadotrophin releasing hormone) elicits pulsatile secretion of LH (luteinising hormone) while chronic treatment with a potent GnRH agonist reduces LH secretion. Using the latter, gonadotrophin-dependent preovulatory antral follicle development may be suppressed, resulting in a uniform cohort of small antral follicles in the absence of a dominant follicle which could then be superstimulated by exogenous gonadotrophin.

scholarly journals Effect of One-Day Delaying CIDR Administration in 5-Day Cosynch Protocol in Dairy Heifers

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1402
Author(s):  
Sükrü Metin Pancarci ◽  
Örsan Güngör ◽  
Osman Harput ◽  
Oguz Calisici
Keyword(s):  
Artificial Insemination ◽  
Follicle Development ◽  
Dominant Follicle ◽  
Dairy Heifers ◽  
Reproductive Management

Effect of one-day delaying progesterone administration at the beginning of 5-day Cosynch protocol was investigated in Holstein heifers for the first artificial insemination (AI). Heifers received a synchronized ovulation and timed AI (TAI) with CIDR inserted on day (d) 0 (CIDR-5; n = 206) or d 1 (CIDR-4; n = 192). In both group, GnRH was administered on d 0 followed by a single PGF2α injection and CIDR removal five days later from GnRH. On d 8, TAI and GnRH administration were concurrently conducted. Heifers detected in estrus up to 24 h prior to TAI were inseminated without GnRH administration. Rates of ovulation, accessory CL formation and new dominant follicle development following initial GnRH injection did not differ between groups. P/AI did not differ between CIDR-4 (44.3%, [85/192]) and CIDR-5 (51.9%, [107/206]) groups, respectively. Pregnancy per AI (P/AI) was significantly (p < 0.01) declined as heifers’ age (12–13, 14, 15, 16 and17–21 months) proceeded in CIDR-4 group (55.6%, 52.1%, 37.9%, 35.7%, 32.4%) compared to those in CIDR-5 group (60.0%, 50.0%, 53.9%, 51.5%, 46.2%) respectively. In conclusion, there is no benefit for delaying CIDR administration in 5-day Cosynch protocol in dairy heifers. However, higher P/AI in CIDR-5 group in older heifers can be considered for reproductive management.

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