scholarly journals 209 NORGESTOMET IMPLANTS REDUCE LH RELEASE PATTERN IN ZEBU COWS UNDERGOING REPEATED OOCYTE PICK-UP

2005 ◽  
Vol 17 (2) ◽  
pp. 255
Author(s):  
J.H.M. Viana ◽  
L.S.A. Camargo ◽  
A.M. Ferreira ◽  
W.F. Sa ◽  
C.A.C. Fernandes ◽  
...  

Ultrasound-guided follicular puncture (OPU) has become the most used technique to recover cumulus-oocyte complexes (COCs) from valuable donors for in vitro embryo production, because of the low risk and the possibility of collecting COCs at intervals as short as twice-a-week. However, repeated aspiration of ovarian follicles may induce endocrine abnormalities due to partial luteinization of punctured follicles and interference with follicular development. The use of exogenous progestagens is an alternative used to control these side effects, and is under evaluation. The aim of this study was to evaluate whether the effect of norgestomet treatment on intra-follicular and systemic steroid concentrations and on ovarian follicular dynamics is related to changes in LH releasing pattern. Pluriparous non-lactating Gir breed (Bos indicus) cows (n = 10) were randomly distributed between treatment (norgestomet ear implants, replaced weekly) and control (no hormone used) groups, and had their ovarian follicles larger than 3 mm in diameter aspirated twice a week, during the next two consecutive weeks. Follicular dynamics were evaluated every 12 h between OPU sessions, and the largest follicles present were used to recover samples of follicular fluid. Blood samples were collected daily for progesterone evaluation in all cows, and 3 times within a 4-h window interval, at 24, 48, 72, and 96 h after follicle puncture for LH evaluation, in 6 cows (3 from treated and 3 from control groups). LH was measured by a standardized RIA procedure. Data was analyzed by ANOVA, and means were compared by Tukey's test. Results are presented as means ± SEM. Treatment with norgestomet reduced mean progesterone plasma concentration during the evaluated period (36.3 ± 14.0 vs. 250.3 ± 49.3 pg/mL; P < 0.0001), the incidence of follicles growing above 9 mm (30% vs. 65%; P < 0.05) in the intervals between OPU sessions, and intrafollicular estradiol and progesterone concentrations in the largest follicles (n = 27) present (265.5 ± 47.4 and 34.9 ± 5.4 ng/mL vs. 765.2 ± 169.1 and 173.3 ± 43.4 ng/mL, respectively; P < 0.05). Plasma LH concentrations were consistently lower during the 3 session intervals in cows treated with norgestomet (0.16 ± 0.04, 0.22 ± 0.03, 0.22 ± 0.09 and 0.17 ± 0.01 vs. 0.44 ± 0.15, 0.53 ± 0.04, 0.42 ± 0.05 and 0.39 ± 0.11 for 24, 48, 72, and 96 h after OPU, respectively; P < 0.05). These results confirm the theory that norgestomet treatment is associated with a reduction in the LH-release pattern, as expected due to the reduction in both luteinization of punctured follicles and in the steroidogenic activity of growing follicles observed during the experiment. The use of norgestomet ear implants can be an alternative in the management of donor cows undergoing oocyte pickup. This work was sponsored by FAPEMIG and CNPq. The authors thank Dr. Robert Douglas for aiding with LH RIA.

2021 ◽  
Vol 10 (13) ◽  
pp. 2757
Author(s):  
Xia Hao ◽  
Amandine Anastácio ◽  
Kenny A. Rodriguez-Wallberg

Fertility preservation through ovarian stimulation, aiming at cryopreserving mature oocytes or embryos, is sometimes unsuccessful. This clinical situation deserves novel approaches to overcome infertility following cancer treatment in patients facing highly gonadotoxic treatment. In this controlled experimental study, we investigated the feasibility of in-vitro culturing secondary follicles isolated from superovulated ovaries of mice recently treated with gonadotropins. The follicle yields of superovulated ovaries were 45.9% less than in unstimulated controls. Follicles from superovulated ovaries showed faster growth pace during the initial 7 days of culture and secreted more 17β-estradiol by the end of culture vs controls. Parameters reflecting the outcome of follicular development and oocyte maturation competence in vitro were similar between superovulated and control groups, with a similar follicle size at the end of culture and around 70% survival. Nearly half of cultured follicles met the criteria for in-vitro maturation in both groups and approximately 60% of those achieved a mature MII oocyte, similarly in both groups. Over 60% of obtained MII oocytes displayed normal-looking spindle and chromosome configurations, without significant differences between the groups. Using a validated follicle culture system, we demonstrated the feasibility of secondary follicle isolation, in-vitro culture and oocyte maturation with normal spindle and chromosome configurations obtained from superovulated mice ovaries.


Zygote ◽  
2021 ◽  
pp. 1-7
Author(s):  
Larissa Zamparone Bergamo ◽  
Denis Vinicius Bonato ◽  
Camila Bizarro-Silva ◽  
Francieli Gesleine Capote Bonato ◽  
Tamires Korchovei Sanches ◽  
...  

Summary The aim of this study was to evaluate the follicular development, morphological integrity, and oxidative stress of preantral ovarian follicles from Bos taurus indicus females grown in vitro with ascorbic acid. Ovaries (n = 20) from Bos taurus indicus females were collected, fragmented, and were cultured in vitro for 6 or 12 days in minimum essential medium (MEM), or MEM supplemented with 50 or 100 ng/ml ascorbic acid, with an extracellular matrix of agarose gel, in an incubator at 38.5°C; every 2 days, 100% of the culture medium was replaced. The data were analyzed using the chi-squared test and/or Fisher’s exact test. In the event of a significant effect, the proportions were compared using a 2 × 2 proportion test. The oxidative stress analysis data were submitted to analysis of variance followed by the Bonferroni test. Values were considered significant when P ≤ 0.05. The addition of 100 ng/ml of ascorbic acid to the in vitro culture medium of preantral ovarian follicles from bovine females promoted follicular development, was efficient in maintaining morphological integrity, as well as the stability of reactive oxygen species, after 6 days of in vitro culture.


1983 ◽  
Vol 103 (3) ◽  
pp. 293-301 ◽  
Author(s):  
Michael Warnhoff ◽  
Gunter Dorsch ◽  
Karl M. Pirke

Abstract. A perfusion system was developed in which isolated median eminences (ME) were stimulated in vitro by depolarizing agents such as potassium and veratridine. Potassium concentrations between 30 and 80 mm released increasing amounts of luteinizing hormone-releasing hormone (LRH) from the MEs of starved and control rats. Veratridine at a concentration of 50 μm caused a more prolonged LRH release in both starved and control animals. LRH secretion in vitro was slightly, though not under all conditions, significantly greater in rats starved for 5 days. The testosterone (T)-LH feedback was studied by castrating the animals and substituting various doses of T through implantation of T-releasing capsules of different sizes. The concentration in plasma, which can prevent the castration-induced much smaller in starved than in control rats. The in vitro release of LRH evoked by 80 mm potassium was not different for starved and fed rats under various feedback conditions. Both groups revealed decreased in vitro release of LRH when castrated animals were not substituted with T. The effect of castration was studied from 1 to 28 days. The plasma LH values rapidly increased in starved and control animals, indicating that the hypothalamic responsestration is not delayed by starvation. The release in vitro of LRH decreased from the first to the fifth day and remained constant thereafter. No significant difference between starved and fed rats was observed. The experiments indicate that the 'releasable pool' of LRH in vitro is greater under conditions of reduced LH release in vivo. The basic mechanism of depolarization-induced exocytosis of LRH from the ME is intact in starved animals.


1990 ◽  
Vol 125 (3) ◽  
pp. 425-432 ◽  
Author(s):  
G. Robinson ◽  
J. J. Evans

ABSTRACT We previously demonstrated that oxytocin stimulates LH release from rat pituitary cells in vitro and advances follicular development and ovulation in mice in vivo. This study reports an investigation of rat LH levels following in-vivo administration of oxytocin. Injection of oxytocin (10 mIU/g, i.p.) to rats at 07.00, 08.00 and 09.00 h of pro-oestrus or at 09.00, 10.00 and 11.00 h of pro-oestrus advanced the onset of the LH surge (P<0.005) and attainment of peak concentrations of LH (P<0.02) in peripheral blood. On the other hand, the descending phase of the LH surge and the surge amplitude were not altered by oxytocin. Treatment at 05.00, 06.00 and 07.00 h of pro-oestrus or at 11.00, 12.00 and 13.00 h of pro-oestrus had no effect on the LH profile. A higher oxytocin dose (20 mIU/g) inhibited LH release when treatment was begun at 05.00, 07.00 or 09.00 h of pro-oestrus. A lower dose (5 mIU/g) was ineffective in altering LH concentrations. In addition, injections of oxytocin (10 mIU/g) at oestrus, metoestrus or dioestrus had no effect on the release of LH. Thus the efficacy of oxytocin in altering concentrations of LH was dose dependent and also critically affected by the day of the oestrous cycle and the time of pro-oestrus. Removal of endogenous oxytocin activity by the use of an oxytocin receptor antagonist abolished the pro-oestrous LH surge, indicating that oxytocin is a vital physiological component of the LH-releasing mechanism in rats. The study provides unequivocal evidence that oxytocin induces LH release in vivo, but the manifestation of oxytocin activity is dependent upon conditions of exposure. Journal of Endocrinology (1990) 125, 425–432


2016 ◽  
Vol 21 (1) ◽  
pp. 26 ◽  
Author(s):  
Muhammad Imron ◽  
Iman Supriatna ◽  
. Amrozi ◽  
Mohamad Agus Setiadi

<p class="abstrak2">Superovulation treatment on PO cattle (Bos indicus) was less responsive compared to Bos taurus breed. It might due to the difference of their follicular dynamic. This study was conducted to investigate the follicular dynamics and its repeatability in PO cattle. Follicular dynamics observations conducted on 9 cows trough ultrasound scanning every day. Observations of wave patterns repeatability were performed in 6 cows which its wave pattern already known on the next consecutive IOI.  Research result indicated that PO cattle had 3 (66%) and 4-waves (34%) pattern. The first wave of 3 and 4-waves pattern emerged on day -0.4+0.9 and 1.4+1.1 respectively.  The second wave of 3 and 4-wave pattern emerged on day 9.8+1.5 and 7.4+1.9 respectively.  The pattern of 3 waves has a longer follicle dominant duration (11.6+1.5 day) in the first wave of estrous cycle, compared with 4 waves pattern (10+2.92 and 7+1.00 day respectively). The growth rate of dominant follicle was not different significantly between the 3 and 4-waves pattern (0.87+0.23 and 0.94+0.25 mm/day respectively). Similarly, ovulatory follicle diameter between 3 and 4-waves pattern was also not different significantly (12.24+12.34 and 12.30+12.23 mm respectively). Observation of wave patterns repeatability in 6 PO cows indicated that PO cattle had high repeatability in follicular wave pattern (0.88) and the number of growing follicle was 0.91.  This study resulted data for dynamic of follicular development, wave pattern, its repeatability which be expected to design the protocol of superovulation treatment or other reproduction technologies based on follicular dynamic to improve its result in PO cattle.</p><p> </p>


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 150-151
Author(s):  
Brianna M Lynnes ◽  
Robert A Cushman ◽  
Jeremy R Miles ◽  
William T Oliver ◽  
Frank F Bartol ◽  
...  

Abstract Colostrum intake by neonatal piglets can be measured using the immunoglobulin immunocrit assay (iCrit). Lactocrine effects occur when maternally derived, milk-borne bioactive factors are transferred to the neonatal circulation with consumption of colostrum during nursing and affect development of somatic tissues, which can have long-term consequences in adulthood. Lactocrine deficiency, indicated by low neonatal iCrit, altered uterine gene expression and reduced fecundity in adult, neonatally lactocrine-deficient gilts. Litter size in pigs is dependent on both ovarian and uterine function. It was hypothesized that lactocrine deficiency affects development of ovarian follicles in gilts. The objective was to determine the number of primordial, primary, and secondary follicles in ovaries of gilts with high (12% ± 0.5; n = 10) or low (1.9% ± 0.4; n = 10) iCrit, determined on postnatal day (PND) 1 after birth. Paired high- and low-iCrit gilts were chosen from the same litters (birth weight; 3.1 ± 0.2 lbs). On PND 14, ovaries were collected and histological sections prepared (3 sections per animal; 30–150 µm apart). Ovarian follicles in each section were staged and the number of follicles in each category were quantified and subjected to ANOVA. Total number of ovarian follicles did not differ with iCrit (P = 0.55; 1,370.6 ± 147.8 follicles per section). The proportion of primordial, primary, and secondary follicles was 89.6 ± 1.15%, 7.7 ± 0.87%, 2.7 ± 0.51%, respectively. The number of primordial (P = 0.55), primary (P = 0.64), and secondary (P = 0.93) follicles did not differ with iCrit. Results indicate that ovarian follicular development of neonatal gilts is not sensitive to immunocrit status. Although lactocrine deficiency did not influence the ovarian follicular profile at PND 14, it remains unknown whether lactocrine programming alters ovarian follicular dynamics in neonatally lactocrine-deficient adults. USDA is an equal opportunity provider and employer.


1986 ◽  
Vol 7 (7) ◽  
pp. 373-379 ◽  
Author(s):  
Peter Axelrod ◽  
George H. Talbot

In vitro fertilization and embryo transfer (IVF-ET) is a process in which human ova are obtained by laparoscopic ovarian follicular puncture, fertilized in vitro by capacitated donor sperm, and introduced transcervically into the uterus. The prospective mother's ovarian cycle is usually stimulated with either clomiphene citrate, human menopausal gonadotropin, or both, so that multiple aspiratable follicles are produced. Follicular development is monitored by ultrasound and by serial serum or urine estrogen determinations. When adequate follicular development has been achieved, a pre-ovulatory dose of human chorionic gonadotropin is administered.


2011 ◽  
Vol 23 (6) ◽  
pp. 788 ◽  
Author(s):  
D. R. Li ◽  
G. S. Qin ◽  
Y. M. Wei ◽  
F. H. Lu ◽  
Q. S. Huang ◽  
...  

This study was carried out to test the feasibility of enhancing embryo production in vivo and in vitro by immunoneutralisation against inhibin or follistatin. In Experiment 1, multi-parity buffaloes were assigned into three groups: High group (n = 8), which received one primary (2 mg) and two booster (1 mg) vaccinations (28-day intervals) with a recombinant inhibin α subunit in 1 mL of white oil adjuvant; Low group (n = 8), which received half that dose; and Control group (n = 7), which received only adjuvant. Immunisation against inhibin stimulated development of ovarian follicles. Following superovulation and artificial insemination, inhibin-immunised buffaloes had more developing follicles than the Control buffaloes. The average number of embryos and unfertilised ova (4.5 ± 0.6, n = 6) in the High group was higher (P < 0.05) than in the Control group (2.8 ± 0.6, n = 5) and was intermediate (4.1 ± 0.7, n = 7) in the Low group. The pooled number of transferable embryos of the High and Low groups (3.2 ± 0.5, n = 13) was also higher (P < 0.05) than that (1.6 ± 0.7, n = 5) of the controls. The immunised groups also had higher plasma concentrations of activin, oestradiol and progesterone. In Experiment 2, the addition of anti-inhibin or anti-follistatin antibodies into buffalo oocyte IVM maturation medium significantly improved oocyte maturation and cleavage rates following parthenogenic activation. Treatment with anti-follistatin antibody also doubled the blastocyst yield from activated embryos. These results demonstrated that immunisation against inhibin stimulated follicular development, enhanced oocyte quality and maturation competence, yielded more and better embryos both in vivo and in vitro.


2013 ◽  
Vol 25 (1) ◽  
pp. 201
Author(s):  
W. C. Marques Filho ◽  
F. C. Destro ◽  
E. Trevisol ◽  
C. M. Queiroz ◽  
M. C. Martins ◽  
...  

The aim of the present study was to evaluate the effects of subcutaneous implants of deslorelin (GnRH agonist-Suprelorin® 4.7 mg) on follicular dynamics and plasma profile of FSH, LH, and progesterone (P4) during the last 20 days of an implantation period of 70 days and after the removal of the implant until the detection of the first ovulation in Nelore cows (Bos indicus). Seven animals had their ovulation synchronized. At the day of the detection of ovulation they received subcutaneous implant of deslorelin. In the last 20 days of the period of treatment, ultrasound scans were taken every 2 or 3 days to characterize the follicular dynamics according to diameter: I (<4 mm), II (4–6 mm), and III (>6 mm). Blood samples were collected to measure plasma concentrations of FSH, LH, and P4. Results were tested by ANOVA, and difference between means was defined using Tukey’s test with significance levels of 0.05. During the 70 days of deslorelin treatment, none of the animals ovulated, despite the implant not suppressing all follicular development. The ultrasound finding was confirmed by P4 plasma concentrations (range: 0.05–0.31 ng mL–1). The normal P4 plasma concentration expected in cycling Nelore cows is about 3.8 ng mL–1 (Satrapa et al. 2010 Reprod. Anim. Dom. 45, 881–887). During the last 20 days of treatment, 4 animals presented follicular development with max diameter ranging through 4 to 6 mm, whereas in the 3 remaining animals, the observed diameter ranged through 9 to 12 mm. The secretion of FSH and LH was not entirely suppressed during the study (range: 1.69–1.39 and 1.37–1.07 ng mL–1, respectively). After the removal of the deslorelin subcutaneous implant, the period of restoration of the ovulatory capacity was 29 days, and the mean diameter of the preovulatory follicle was 12.5 mm. The P4 plasma concentrations during this time were low (range: 0.15–0.09 ng mL–1). During the recovery period, the phenomenon of follicular codominance and double ovulation in 2 animals (2/7) was observed. From the results obtained, it can be concluded that the total implant treatment of 70 days with deslorelin in cows inhibits ovulation by not allowing LH surge, although the follicular development is not completely depressed. The financial support of FAPESP, Fundunesp, and CNPq are acknowledged.


Author(s):  
T. Caceci ◽  
A.A. Shaikh ◽  
D.C. Kraemer

Five baboons were treated during seven menstrual cycles with 5.0 mg of FSH-P for five days, starting on either day 3 or day 5 of the cycle. On day 5 of the treatment, the ovaries were examined by laparoscopy to evaluate follicular development. All animals exhibited multiple preovulatory follicles and at that time 100 mg GnRH was administered intramuscularly to induce LH release. Between 24 and 30 hours after injection of GnRH, laparoscopic follicular aspiration was used to collect oocytes. These were matured in vitro (determined by extrusion of the first polar body) and fertilized by microinjection with frozen-thawed baboon spermatozoa. Male and female pronuclei were observed in 32% of the resulting zygotes within 24 hours. These zygotes were compared to a zygote in the same stage that had been fertilized in vivo and obtained by laparoscopy and flushing of the oviduct.


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