Follicle Diameter (follicle + diameter)

Distribution by Scientific Domains


Selected Abstracts


The reproductive biology and ecology of the Port Jackson shark Heterodontus portusjacksoni in the coastal waters of eastern Australia

JOURNAL OF FISH BIOLOGY, Issue 10 2008
D. M. Powter
The reproductive biology and ecology of the Port Jackson shark Heterodontus portusjacksoni was investigated at three locations on the central and southern coast of New South Wales (NSW), Australia from January 2002 to December 2005 using underwater visual census surveys and samples obtained from a commercial fishery. Adults displayed sexual dimorphism in total length (LT) at sexual maturity, with males maturing between 762 and 772 mm LT and females between 902 and 905 mm LT. The mean ovarian fecundity was estimated at 16 offspring per female but was unrelated to female LT. Male gonado-somatic (IG) and hepato-somatic (IH) indices and female IG declined from July to November as did maximum ovarian follicle diameter and the diameter of the three largest follicles. Adults were absent from inshore reefs between December and July. Hence, H. portusjacksoni has a synchronous annual breeding season in NSW, which occurs between July and November (the austral winter to spring), with a peak in oviposition from August to October. Heterodontus portusjacksoni copulatory and ovipository behaviour are reported for the first time. Copulation was observed and involved oral grasping of the female's pectoral fin by a single male, which wrapped his body around hers to insert one clasper. Ovipositing females appeared to search crevices in the reef prior to delivering a single capsule, which was washed into the crevice by water movement, with the female departing very soon after oviposition. This study represents the first rigorously quantitative analysis of H. portusjacksoni reproductive biology and ecology in NSW waters. [source]


Ovarian follicular development stimulated by leuprorelin acetate plus human menopausal gonadotropin in chimpanzees

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 2 2005
Nobuhiko Yoshimoto
Abstract:, We attempted ovarian stimulation using gonadotropins in 14 chimpanzees. Subjects were given a single administration of leuprorelin acetate, followed by repeated administration of human menopausal gonadotropin (hMG) for 16,21 days. During the dosing period, the ovarian follicle diameter and count were measured by transvaginal ultrasonography. The hormone administration induced the development of multiple follicles, and multiple oocytes were subsequently retrieved. However, the follicle count was decreased, suggesting atresia, in some subjects. Statistically, the final follicle diameter was dependent on the dosing duration and the hMG dose in the late stage, while the maximum follicle count during hMG administration was dependent on age and the hMG dose in the early stage. Five subjects showed mild ovarian hyperstimulation syndrome (OHSS)-like symptoms with a high serum estradiol (E2) concentration. These results suggest that leuprorelin acetate plus hMG administration successfully stimulates the development of multiple ovarian follicles for oocyte retrieval and that the serum E2 concentration is predictive of OHSS-like symptoms in chimpanzees. [source]


Ovarian Structure in Mice Lines Selected for Weight

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009
S. F. Bernardi
Summary Selection for body weight at 49 day of age (s and h, downward selected lines; s, and h,, upward selected lines) affected reproductive traits in CF1 mice lines. The objective of this study was to compare ovarian structures in females of these lines, as well as in unselected controls (Line t). The number of ovarian follicles (N), follicle diameter (FD), number of corpora lutea (CL), litter size (LS), and body weight (W), were recorded. There were significant differences among lines for N, FD, CL, LS and W; means values for the lines with the greatest difference for post-pubertal females were: Ns = 19.3 and Ns, = 32.7; FDh, = 161.7 and FDs, = 178.2; CLh = 10.3 and CLs, = 21.9; LSs = 6.0 and LSh, = 11.1; Wh = 18.9 and Ws, = 32.4. There were also differences between positive lines; Line s, had a higher proportion of large follicles in pre-pubertal females, a greater capacity to convert these follicles into CL, but a lower capacity to maintain embryos until term than Line h,. For negative lines, Line h apparently had a reduced incidence of embryonic loss when compared with Line s. In conclusion, selection for body weight modified ovarian structure, as well as reproductive efficiency. [source]


Survival rate of preantral follicles derived from vitrified neonate mouse ovarian tissue by cryotop and conventional methods

BIOFACTORS, Issue 2 2007
H. Eimani
Abstract The aim of this study was to investigate the growth and survival rate of preantral follicles isolated from vitrified ovarian tissue by Cryotop and conventional methods. The ovaries of 14-day-old mice were separated and divided into four groups as following: Cryotop group, vitrified by Cryotop; CV (Conventional; CV) group, vitrified by conventional straw; toxicity test group and control group. After warming the vitrified ovaries, isolated preantral follicles from four groups were cultured for 4 days to compare survival rate and follicular growth between above-mentioned groups. Survival rate (97.3%) in toxicity test group alike the control group (98.7%) were significantly higher (P < 0.05) than the Cryotop (92.7%) and CV (47.7%) groups. Increase in follicle diameters after 4 days in Cryotop and CV groups was significantly lower (P < 0.05) than the control and toxicity test groups, but growth and survival rate of follicles in Cryotop group was significantly higher (P < 0.05) than the CV group. These results demonstrated that ovarian tissue vitrification by Cryotop highly preserves the viability rate of preantral follicles. [source]


FSH and ovarian response: spontaneous recovery of pituitary,ovarian activity during the pill-free period vs. exogenous recombinant FSH during high-dose combined oral contraceptives

CLINICAL ENDOCRINOLOGY, Issue 4 2002
A. M. Van Heusden
Summary ojbective Compare spontaneous recovery of pituitary,ovarian activity during the pill-free period following the correct use of low-dose oral contraceptives and subsequent ovarian function during the administration of exogenous recombinant FSH (recFSH) after switching to continued Lyndiol® (2·5 mg lynestrenol + 0·05 mg ethinyl-oestradiol) medication. design Prospective, randomized, group-comparative, single-centre study. Following the monitoring of the pill-free period (week 1) and subsequent treatment with Lyndiol® (for a total of 5 weeks), all subjects were randomly allocated to one of four groups receiving daily FSH injections for 1 week [75, 150, 225 IU recFSH or 150 IU purified urinary FSH (uFSH)] during the fourth week of Lyndiol® use. patients Thirty-six healthy volunteers aged 18,39 years, prestudy oral contraceptive use for at least 3 months, cycle length between 24 and 35 days. measurements Serum FSH, LH and oestradiol (E2) concentrations as well as transvaginal ultrasound assessment of the number and diameter of follicles > 2 mm were used to monitor pituitary ovarian function. results At the start of the pill-free period following the prestudy contraceptive medication, 67% of the women presented with LH and FSH levels < 1 IU/l and only one follicle > 10 mm was observed. Initial levels of LH and FSH correlated (P < 0·05) with the extent of pituitary,ovarian activity during the pill-free period. At the end of the pill-free period a follicle > 10 mm had emerged in one subject only. During the first 3 days of Lyndiol® use, seven women (19%) eventually showed at least one follicle > 10 mm. During combined exogenous FSH and Lyndiol® administration, LH levels remained completely suppressed (, 0·5 IU/l) in all women studied. FSH levels and number and size of follicles increased with increasing doses of exogenous FSH in a dose-dependent manner. E2 levels remained low in all groups (< 150 pmol/l). During the week following FSH administration, FSH levels and E2 levels decreased gradually while the number of follicles > 10 mm still increased. conclusions We have confirmed that dominant follicles > 10 mm are present at the end of the pill-free period and during the first days after resumption of pill intake. Once follicles > 10 mm arose at the end of the pill-free period, continued use of Lyndiol® did not reduce follicle diameters. One week of Lyndiol® reduces pituitary,ovarian activity to levels observed after 3 weeks of low-dose pills. FSH administration during Lyndiol® resulted in dose-dependent follicle growth despite extremely low LH levels. E2 secretion (56 ± 51 pmol/l) occurred to a limited and variable extent along with extremely low serum LH concentrations. Recovery of pituitary,ovarian activity at the end of the pill-free period is comparable to FSH levels and follicle dynamics following 7 days of 75,150 IU/l recFSH. [source]