scholarly journals 204 ASSOCIATION BETWEEN SOME ULTRASONIC CHARACTERISTICS OF CORPUS LUTEUM ANDPROGESTERONE VALUES IN CASPIAN MINIATURE MARES

2005 ◽  
Vol 17 (2) ◽  
pp. 252
Author(s):  
F. Gharagozloo ◽  
A. Shirazi
Keyword(s):  
Corpus Luteum ◽  
Maximum Size ◽  
Wave Pattern ◽  
Repeated Measure ◽  
Minimum Size ◽  
Blood Collection ◽  
Hormonal Changes ◽  
Estrus Cycle ◽  
Plasma Progesterone ◽  
Caspian Miniature Horse

Reproductive characteristics of the Caspian miniature horse have some similarities to other equine breeds, but several differences such as follicular wave pattern, multiple ovulations, and the size of ovulatory follicle have been reported. Still there are some other characteristics to be determined. This study was carried out to investigate ultrasonic and hormonal changes of the Caspian mares during estrus cycle. Eleven clinically healthy and cycling Caspian mares, aged 3–17 years and weighing 159–236 kg L.W., were used from April to July. Using an ultrasound scanner equipped with a 5-MHz, B-mode, linear array rectal transducer, formation of the corpus luteum was observed from Day 0 (day of ovulation), and changes in plasma progesterone were investigated by daily blood collection and assay by means of an RIA method. Repeated measure ANOVA test was used for statistical analysis. The maximum size of the corpus luteum was seen at Day 3 postovulation (36.6 ± 1.91 mm), and remained up to 10 days after ovulation. At Days 10–11 a significant decrease in size was observed; thereafter gradual regression occurred and minimum size was reached by Days 16–17 (17.3 ± 1.46 and 16.9 ± 1.20 mm, respectively). The first significant increase in progesterone level was detected 24 h after ovulation and average high values of 8 ng/mL by Day 4 after ovulation. The average peak value of progesterone was detected on Days 7 to 10 of the cycle (11.6 ± 1.37 ng/mL) and remained so until Day 12. The lowest plasma progesterone concentration (less than 1 ng/mL) was observed from Day 14 till one day postovulation, coinciding with the CL regression found in sonographic observations. The results of this study revealed that the pattern of corpus luteum formation and Its changes in size and the plasma progesterone levels during the estrus cycle in this breed follow a pattern similar to that of other equine breeds. The authors wish to thank the University of Tehran for funding and Khojir stud farm for providing animals.

314 EARLY PREGNANCY DIAGNOSIS USING A NOVEL TRANSRECTAL ULTRASONOGRAPHY PROTOCOL IN JAPANESE BLACK COWS

2009 ◽  
Vol 21 (1) ◽  
pp. 254
Author(s):  
A. Gaja ◽  
C. Kubota ◽  
T. Kojima
Keyword(s):  
Corpus Luteum ◽  
Early Pregnancy ◽  
Transrectal Ultrasonography ◽  
Blood Collection ◽  
Sectional Area ◽  
Cross Sectional ◽  
Plasma Progesterone ◽  
Area Change ◽  
Pregnancy Diagnosis ◽  
Peripheral Plasma

The present study aims to establish a novel practical protocol for early pregnancy diagnosis in cows by using transrectal ultrasonography. The protocol is based on measurements of corpus luteum (CL) cross-sectional area (CL c-s area) change performed at 2 separate days before the coming estrus after AI. Fourteen cows were inseminated artificially, and transrectal ultrasonographical observation of the ovaries and blood collection for measurement of peripheral plasma progesterone (P4) concentration were carried out daily from Days 12 to 23 (Day 0 = the day of onset of estrus). Thereafter, cows were routinely diagnosed for pregnancy at Day 30 by transrectal ultrasonography. The largest CL c-s area was obtained at Day 14 in both pregnant and non-pregnant cows. Seven out of 8 non-pregnant cows showed significant CL c-s area regression between Days 14 and 20 (422 ± 112 v. 249 ± 63 mm2), whereas no regression was observed between Days 14 and 20 in pregnant cows (416 ± 65 v. 402 ± 78 mm2). The regression in the CL c-s area between pregnant and non-pregnant cows was significantly different during Day 18 (424 ± 65 v. 288 ± 88 mm2) to Day 23 (402 ± 71 v. 139 ± 64 mm2). P4 concentration was significantly low (less than 1 ng mL–1) at Day 20 in 3 out of 8 non-pregnant cows, whereas the pregnant cows showed significant increase of P4 between Days 14 and 20 (2.6 ± 0.2 v. 3.4 ± 0.5 ng mL–1). The pregnant cows showed significantly higher P4 concentration starting from Day 18 than non-pregnant cows. However, in non-pregnant cows, 4 cows returned to estrus on Day 20 or after, 3 cows showed no signs of estrus, and 1 cow came in estrus as early as Day 18 after AI. In conclusion, the results of the present study suggest that measuring the change in the CL c-s area at Days 14 and 20 makes it possible to detect the non-pregnant cows at Day 20 after AI. However, it was also indicated that measuring the change of P4 concentrations on the same days did not always successfully detect non-pregnant cows. The new protocol based on CL c-s area regression rate can detect almost certainly non-pregnant cows at Day 20 after AI. It is suggested that this method is advantageous in research and industrial breeding.

PROGESTERONE IN THE HUMAN PERIPHERAL BLOOD IN THE PREOVULATORY PERIOD OF THE MENSTRUAL CYCLE

1967 ◽  
Vol 55 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Benno Runnebaum ◽  
Josef Zander
Keyword(s):  
Menstrual Cycle ◽  
Corpus Luteum ◽  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Progesterone Concentration ◽  
Plasma Progesterone ◽  
Progesterone Secretion ◽  
Graafian Follicle ◽  
The Mean ◽  
Mean Concentration

ABSTRACT Progesterone was determined and identified in human peripheral blood during the preovulatory period of the menstrual cycle, by combined isotope derivative and recrystallization analysis. The mean concentration of progesterone in 1.095 ml of plasma obtained 9 days before ovulation was 0.084 μg/100 ml. However, the mean concentration of progesterone in 1.122 ml of plasma obtained 4 days before ovulation was 0.279 μg/100 ml. These data demonstrate a source of progesterone secretion other than the corpus luteum. The higher plasma-progesterone concentration 4 days before ovulation may indicate progesterone secretion of the ripening Graafian follicle of the ovary.

GONADAL HORMONES AND THE CONTROL OF OVULATION IN THE GUINEA-PIG

1972 ◽  
Vol 55 (3) ◽  
pp. 599-607 ◽  
Author(s):  
B. T. DONOVAN ◽  
A. N. LOCKHART
Keyword(s):  
Guinea Pig ◽  
Corpus Luteum ◽  
Acute Treatment ◽  
Gonadal Hormones ◽  
Time Of Day ◽  
Gonadal Steroids ◽  
Corpora Lutea ◽  
Plasma Progesterone ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate

SUMMARY The release of ovulating hormone after acute treatment with gonadal steroids, or corpus luteum removal on different days of the oestrous cycle, was studied in the guinea-pig. Injection of 25, 50 or 100 μg oestradiol or 2·5 mg progesterone on day 13 of the cycle had no effect upon gonadotrophin secretion as judged by follicular histology, but markedly altered the sizes of the corpora lutea of the previous ovulation. Treatment with oestradiol on day 14 did not elicit gonadotrophin secretion. However, administration of the same hormones to animals given 10 μg oestradiol benzoate 24 h earlier caused ovulation or follicular luteinization. Progesterone (2·5 mg) appeared least effective in stimulating gonadotrophin release; 25 μg oestradiol were more effective when given at 12.00 h than at 24.00 h but treatment with both hormones caused ovulation when given at either time of day. Luteal volumes were not affected. Removal of corpora lutea during the second half of the cycle advanced the time of expected ovulation to day 15 or earlier when the procedure was carried out on days 8 or 9, but not on days 10–13. It is concluded that 4–5 days must elapse between the fall in plasma progesterone level associated with corpus luteum regression and the release of ovulating hormone.

scholarly journals Does the rate of orthodontic tooth movement change during the estrus cycle? A systematic review based on animal studies

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Noura Saeed Sultan Almidfa ◽  
Athanasios E. Athanasiou ◽  
Miltiadis A. Makrygiannakis ◽  
Eleftherios G. Kaklamanos
Keyword(s):  
Animal Studies ◽  
Tooth Movement ◽  
Citation Index ◽  
Cochrane Review ◽  
Orthodontic Tooth Movement ◽  
Risk Of Bias ◽  
Cochrane Library ◽  
Hormonal Changes ◽  
Estrus Cycle ◽  
Russian Science Citation Index

Abstract Background As the fluctuation of sex hormone levels in menstruating women results in periodical effects in bone metabolism, understanding the implications for tooth movement could be of benefit to the orthodontist. This type of research presents practical and ethical problems in humans, but animal models could provide useful information. Our objective was to systematically investigate the available evidence on the question whether the rate of orthodontic tooth movement varies between the different stages of the estrus cycle in animals. Methods Unrestricted searches in 7 databases and manual searching of the reference lists in relevant studies were performed up to February 2021 (Medline [PubMed], CENTRAL [Cochrane Library; includes records from Embase, CINAHL, ClinicalTrials.gov, WHO's ICTRP, KoreaMed, Cochrane Review Groups’ Specialized Registers, and records identified by handsearching], Cochrane Database of Systematic Reviews [Cochrane Library], Scopus, Web of Knowledge [including Web of Science Core Collection, KCI Korean Journal Database, Russian Science Citation Index, SciELO Citation Index and Zoological Record], Arab World Research Source [EBSCO] and ProQuest Dissertation and Theses [ProQuest]). Our search focused on prospective controlled animal studies, whose samples included female subjects of any species that were quantitatively comparing the amount of tooth movement in the different stages of the estrus cycle. Following study retrieval and selection, relevant data was extracted, and the risk of bias was assessed using the SYRCLE’s Risk of Bias Tool. Results From the finally assessed records, 3 studies met the inclusion criteria. Two of the studies experimented on Wistar rats, whereas the other on cats. Tooth movement was induced by expansion or coil springs. The rate of orthodontic tooth movement was increased during the stages of the estrus cycle when oestrogen and/or progesterone levels were lower. The risk of bias in the retrieved studies was assessed to be unclear. Conclusion Hormonal changes during the estrus cycle may affect the rate of orthodontic tooth movement. Although these animal experiment results should be approached cautiously regarding their translational potential, it could be useful to consider the possible impact of these physiological changes in the clinical setting until more information becomes available. Registration: PROSPERO (CRD42021158069).

scholarly journals The absence of corpus luteum formation alters the endocrine profile and affects follicular development during the first follicular wave in cattle

Reproduction ◽  
2008 ◽  
Vol 136 (6) ◽  
pp. 787-797 ◽  
Author(s):  
Ken-Go Hayashi ◽  
Motozumi Matsui ◽  
Takashi Shimizu ◽  
Natsuko Sudo ◽  
Ayako Sato ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Area Under The Curve ◽  
Follicular Development ◽  
Experimental Period ◽  
Pulse Amplitude ◽  
Pulse Frequency ◽  
Blood Collection ◽  
Gh Secretion ◽  
Endocrine Profile ◽  
Basal Concentration

We previously established a bovine experimental model showing that the corpus luteum (CL) does not appear following aspiration of the preovulatory follicle before the onset of LH surge. Using this model, the present study aimed to determine the profile of follicular development and the endocrinological environment in the absence of CL with variable nadir circulating progesterone (P4) concentrations during the oestrous cycle in cattle. Luteolysis was induced in heifers and cows and they were assigned either to have the dominant follicle aspirated (CL-absent) or ovulation induced (CL-present). Ultrasound scanning to observe the diameter of each follicle and blood collection was performed from the day of follicular aspiration or ovulation and continued for 6 days. The CL-absent cattle maintained nadir circulating P4throughout the experimental period and showed a similar diameter between the largest and second largest follicle, resulting in co-dominant follicles. Oestradiol (E2) concentrations were greater in the CL-absent cows than in the CL-present cows at day −1, day 1 and day 2 from follicular deviation. The CL-absent cows had a higher basal concentration, area under the curve (AUC), pulse amplitude and pulse frequency of LH than the CL-present cows. After follicular deviation, the CL-absent cows showed a greater basal concentration, AUC and pulse amplitude of growth hormone (GH) than the CL-present cows. These results suggest that the absence of CL accompanying nadir circulating P4induces an enhancement of LH pulses, which involves the growth of the co-dominant follicles. Our results also suggest that circulating levels of P4and E2affect pulsatile GH secretion in cattle.

Inductive graph invariants and approximation algorithms

2021 ◽  
Author(s):  
C. R. Subramanian
Keyword(s):  
Optimization Problems ◽  
Independence Number ◽  
Optimal Solution ◽  
Maximum Size ◽  
Chordal Graphs ◽  
Minimum Size ◽  
Optimal Size ◽  
Induced Subgraph ◽  
Special Cases ◽  
Optimal Formula

We introduce and study an inductively defined analogue [Formula: see text] of any increasing graph invariant [Formula: see text]. An invariant [Formula: see text] is increasing if [Formula: see text] whenever [Formula: see text] is an induced subgraph of [Formula: see text]. This inductive analogue simultaneously generalizes and unifies known notions like degeneracy, inductive independence number, etc., into a single generic notion. For any given increasing [Formula: see text], this gets us several new invariants and many of which are also increasing. It is also shown that [Formula: see text] is the minimum (over all orderings) of a value associated with each ordering. We also explore the possibility of computing [Formula: see text] (and a corresponding optimal vertex ordering) and identify some pairs [Formula: see text] for which [Formula: see text] can be computed efficiently for members of [Formula: see text]. In particular, it includes graphs of bounded [Formula: see text] values. Some specific examples (like the class of chordal graphs) have already been studied extensively. We further extend this new notion by (i) allowing vertex weighted graphs, (ii) allowing [Formula: see text] to take values from a totally ordered universe with a minimum and (iii) allowing the consideration of [Formula: see text]-neighborhoods for arbitrary but fixed [Formula: see text]. Such a generalization is employed in designing efficient approximations of some graph optimization problems. Precisely, we obtain efficient algorithms (by generalizing the known algorithm of Ye and Borodin [Y. Ye and A. Borodin, Elimination graphs, ACM Trans. Algorithms 8(2) (2012) 1–23] for special cases) for approximating optimal weighted induced [Formula: see text]-subgraphs and optimal [Formula: see text]-colorings (for hereditary [Formula: see text]’s) within multiplicative factors of (essentially) [Formula: see text] and [Formula: see text] respectively, where [Formula: see text] denotes the inductive analogue (as defined in this work) of optimal size of an unweighted induced [Formula: see text]-subgraph of the input and [Formula: see text] is the minimum size of a forbidden induced subgraph of [Formula: see text]. Our results generalize the previous result on efficiently approximating maximum independent sets and minimum colorings on graphs of bounded inductive independence number to optimal [Formula: see text]-subgraphs and [Formula: see text]-colorings for arbitrary hereditary classes [Formula: see text]. As a corollary, it is also shown that any maximal [Formula: see text]-subgraph approximates an optimal solution within a factor of [Formula: see text] for unweighted graphs, where [Formula: see text] is maximum size of any induced [Formula: see text]-subgraph in any local neighborhood [Formula: see text].

Development and regression of the corpus luteum in grey seal (Halichoerus grypus) ovaries and its use in determining fertility rates

1984 ◽  
Vol 62 (6) ◽  
pp. 1095-1100 ◽  
Author(s):  
I. L. Boyd
Keyword(s):  
Corpus Luteum ◽  
Adult Female ◽  
Halichoerus Grypus ◽  
Embryonic Diapause ◽  
Grey Seal ◽  
Fertility Rates ◽  
Reproductive Condition ◽  
Plasma Progesterone ◽  
Blood Samples ◽  
Foetal Growth

Adult female grey seals were sampled at the Fame Islands at monthly intervals from November 1980 to October 1981. The distribution, size, and number of ovarian corpora were recorded in each case and blood samples were obtained for progesterone analysis. The concentration of plasma progesterone was about 6 ng/mL for most of gestation, including embryonic diapause, and rose to about 10 ng/mL during the final month. Progesterone declined sharply to less than 1 ng/mL at parturition. The size of the corpus luteum was constant throughout embryonic diapause, but after implantation it grew continuously until parturition. Following parturition, it regressed rapidly at first, forming a corpus albicans, and then more slowly, regression being arrested during the period of foetal growth of the following reproductive cycle. Most corpora albicantia had disappeared 1 year after their formation. Corpora albicantia may be useful indicators of reproductive history in grey seals, providing that allowance is made for the reproductive condition of females at the time of sampling and for several other possible errors which could arise. Retrospective calculation of reproductive statistics by more than 1 year using corpora albicantia is not valid for grey seals.

scholarly journals Delayed effect of low progesterone concentrations on bovine uterine PGF(2alpha) secretion in the subsequent oestrous cycle

Reproduction ◽  
2001 ◽  
pp. 643-648 ◽  
Author(s):  
A Shaham-Albalancy ◽  
Y Folman ◽  
M Kaim ◽  
M Rosenberg ◽  
D Wolfenson
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Oestrous Cycle ◽  
Delayed Effect ◽  
Plasma Progesterone ◽  
Progesterone Secretion ◽  
Progesterone Treatment ◽  
Late Luteal Phase ◽  
Subsequent Cycle ◽  
Concentration Curves

Low progesterone concentrations during the bovine oestrous cycle induce enhanced responsiveness to oxytocin challenge late in the luteal phase of the same cycle. The delayed effect of low progesterone concentrations during one oestrous cycle on uterine PGF(2alpha) secretion after oxytocin challenge on day 15 or 16 of the subsequent cycle was studied by measuring the concentrations of the major PGF(2alpha) metabolite (13,14-dihydro-15-keto PGF(2alpha); PGFM) in plasma. Two experiments were conducted, differing in the type of progesterone treatment and in the shape of the low progesterone concentration curves. In Expt 1, progesterone supplementation with intravaginal progesterone inserts, with or without an active corpus luteum, was used to obtain high, or low and constant plasma progesterone concentrations, respectively. In Expt 2, untreated cows, representing high progesterone treatment, were compared with cows that had low but increasing plasma progesterone concentrations that were achieved by manipulating endogenous progesterone secretion of the corpus luteum. Neither experiment revealed any differences in plasma progesterone concentrations between the high and low progesterone groups in the subsequent oestrous cycle. In both experiments, both groups had similar basal concentrations of PGFM on day 15 (Expt 1) or 16 (Expt 2) of the subsequent oestrous cycle, 18 days after progesterone treatments had ended. In both experiments, the increases in PGFM concentrations in the low progesterone groups after an oxytocin challenge were markedly higher than in the high progesterone groups. These results indicate that low progesterone concentrations during an oestrous cycle have a delayed stimulatory effect on uterine responsiveness to oxytocin during the late luteal phase of the subsequent cycle. This resulting increase in PGF(2alpha) secretion may interfere with luteal maintenance during the early stages of pregnancy.

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