A note on the induction of ovulation in lactating red deer hinds prior to the breeding season

1989 ◽  
Vol 49 (1) ◽  
pp. 134-138 ◽  
Author(s):  
M. W. Fisher ◽  
P. F. Fennessy ◽  
G. H. Davis
Keyword(s):  
Corpus Luteum ◽  
Breeding Season ◽  
Untreated Control ◽  
Red Deer ◽  
Osmotic Pump ◽  
Induction Of Ovulation ◽  
Induced Ovulation ◽  
Pre Treatment

Methods of inducing ovulation 3 weeks prior to the onset of the breeding season were evaluated in lactating adult red deer. Following 11 days of intravaginal progesterone pre treatment, hinds were either untreated (control), or given 300 i.u. PMSG i.m. or 500 mglh GnRH s.c. by osmotic pump. All hinds were laparoscoped 7 days after progesterone withdrawal to record the presence or absence of a corpus luteum on the ovaries, Laparoscopy showed 0113 control, 11113 PMSG and 8/13 GnRH-treated hinds ovulated indicating that during lactation, both methods of inducing ovulation are similarly effective, However, although these treatments induced ovulation, fertility as assessed from calving records, was poor.

INDUCTION OF OVULATION BY GONADOTROPHINS IN THE INDIAN FIVE-STRIPED PALM SQUIRREL FUNAMBULUS PENNANTI (WROUGHTON)

1967 ◽  
Vol 39 (3) ◽  
pp. 369-NP ◽  
Author(s):  
PUSHPA SETH ◽  
M. R. N. PRASAD
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Follicular Growth ◽  
Induction Of Ovulation ◽  
Induced Ovulation ◽  
Follicular Maturation ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Superovulation was induced in palm squirrels by the administration of gonadotrophins. The regimen of treatment effective in inducing ovulation was 60 i.u. pregnant mare serum gonadotrophin (PMS) administered in three doses of 20 i.u. on days 1, 4 and 7, followed by a single injection of 40 i.u. human chorionic gonadotrophin (HCG) on day 14. The same schedule of PMS and HCG administration induced ovulation in mature and immature squirrels both during the breeding season and the period of sexual quiescence. Ovulation did not occur in PMS-treated females if HCG was not administered. The period required for follicular growth before the follicles responded to the ovulatory stimulus of HCG was 13–14 days; the interval for follicular maturation leading to the release of the ovum was approximately 24 hr. Variations in the numbers of ova shed by different groups of females are related to the phase of the reproductive cycle and the age of the squirrels.

Induction of ovulation in goldfish by clomiphene citrate

1972 ◽  
Vol 50 (12) ◽  
pp. 1679-1680 ◽  
Author(s):  
S. Pandey ◽  
W. S. Hoar
Keyword(s):  
Clomiphene Citrate ◽  
Induction Of Ovulation ◽  
Induced Ovulation

Clomiphene citrate induced ovulation in gravid goldfish. The stripped eggs were viable and on fertilization developed into normal fry.

scholarly journals Senolytic Peptide FOXO4-DRI Selectively Removes Senescent Cells From in vitro Expanded Human Chondrocytes

2021 ◽  
Vol 9 ◽  
Author(s):  
Yuzhao Huang ◽  
Yuchen He ◽  
Meagan J. Makarcyzk ◽  
Hang Lin
Keyword(s):  
Untreated Control ◽  
Cell Number ◽  
Cartilage Tissue ◽  
Population Doubling ◽  
Control Group ◽  
Chondrocyte Implantation ◽  
Cartilage Injuries ◽  
Pre Treatment ◽  
Articular Cartilage Injuries

Autologous chondrocyte implantation (ACI) is a procedure used to treat articular cartilage injuries and prevent the onset of post-traumatic osteoarthritis. In vitro expansion of chondrocytes, a necessary step in ACI, results in the generation of senescent cells that adversely affect the quality and quantity of newly formed cartilage. Recently, a senolytic peptide, fork head box O transcription factor 4-D-Retro-Inverso (FOXO4-DRI), was reported to selectively kill the senescent fibroblasts. In this study, we hypothesized that FOXO4-DRI treatment could remove the senescent cells in the expanded chondrocytes, thus enhancing their potential in generating high-quality cartilage. To simulate the in vitro expansion for ACI, chondrocytes isolated from healthy donors were expanded to population doubling level (PDL) 9, representing chondrocytes ready for implantation. Cells at PDL3 were also used to serve as the minimally expanded control. Results showed that the treatment of FOXO4-DRI removed more than half of the cells in PDL9 but did not significantly affect the cell number of PDL3 chondrocytes. Compared to the untreated control, the senescence level in FOXO4-DRI treated PDL9 chondrocytes was significantly reduced. Based on the result from standard pellet culture, FOXO4-DRI pre-treatment did not enhance the chondrogenic potential of PDL9 chondrocytes. However, the cartilage tissue generated from FOXO4-DRI pretreated PDL9 cells displayed lower expression of senescence-relevant secretory factors than that from the untreated control group. Taken together, FOXO4-DRI is able to remove the senescent cells in PDL9 chondrocytes, but its utility in promoting cartilage formation from the in vitro expanded chondrocytes needs further investigation.

Effects of chronic long-acting bromocriptine treatment on liveweight, voluntary food intake, coat growth and breeding season in non-pregnant red deer hinds

1988 ◽  
Vol 119 (3) ◽  
pp. 413-420 ◽  
Author(s):  
J. D. Curlewis ◽  
A. S. I. Loudon ◽  
J. A. Milne ◽  
A. S. McNeilly
Keyword(s):  
Food Intake ◽  
Breeding Season ◽  
Red Deer ◽  
Vehicle Group ◽  
High Dose ◽  
Group A ◽  
Long Acting ◽  
Group B ◽  
Voluntary Food Intake

ABSTRACT Seventeen red deer hinds were housed in individual pens and from 28 February until 11 November were injected each week with vehicle (group A; n = 6) or 5 (group B; n = 6) or 12·5 mg (group C; n = 5) of a long-acting formulation of bromocriptine. Liveweight and voluntary food intake (VFI) were recorded for each hind, and blood was collected for determination of progesterone, prolactin, tri-iodothyronine (T3) and cortisol concentrations by radioimmunoassay. Treatment with the high dose of bromocriptine was associated with a significant (P <0·05) reduction in VFI, with the effect being greatest between March and July. There was no treatment effect on liveweight, but there was a significant (P <0·01) interaction between time and treatment due to the faster rate of weight gain in control animals at the beginning of the experiment. Changes in liveweight could be explained by changes in VFI rather than by changes in the efficiency of utilization of intake. Termination of the breeding season was significantly (P <0·01) delayed by 54 days in group C hinds. Growth of the summer coat and subsequent winter coats was delayed by 1 and 3 months respectively in group C hinds, and in groups B and C the duration that animals were in summer coat was increased by about 1 month. The seasonal increase in prolactin concentrations was seen in all groups, but levels were significantly (P <0·05) lower in group C hinds. Concentrations of T3 and cortisol were not affected by bromocriptine. J. Endocr. (1988) 119, 413–420

scholarly journals Deslorelin treatment of hyperoestrogenism in neutered ferrets (Mustela putorius furo): a case report

2009 ◽  
Vol 54 (No. 2) ◽  
pp. 89-95 ◽  
Author(s):  
A. Prohaczik ◽  
M. Kulcsar ◽  
Gy. Huszenicza
Keyword(s):  
Untreated Control ◽  
Slow Release ◽  
Clinical Signs ◽  
Gnrh Analogue ◽  
Mustela Putorius ◽  
Blood Samples ◽  
Nodular Hyperplasia ◽  
Normal Hair ◽  
Pre Treatment ◽  
Subcutaneous Implant

Hyperoestrogenism causing progressive alopecia in neutered ferrets may be induced by ovarian remnant syndrome (ORS) and nodular hyperplasia of the adrenocortex (hyperadrenocorticism, NHA). The objective of the study was to determine whether a slow-release implant of a gonadotropin releasing hormone (GnRH) analogue, deslorelin, has any value in therapy of hyperoestrogenism of adrenocortical origin (NHA). Three supposed cases of NHA with alopecia and other clinical signs of hyperoestrogenism (<i>n</i> = 2 spayed females in oestrous and <i>n</i> = 1 castrated male) were treated with a subcutaneous implant of 4.7 mg deslorelin acetate. Blood samples were collected, and plasma levels of estradiol (E<sub>2</sub>) were determined just before, and some weeks after treatment. For realistic monitoring, blood samples for E<sub>2</sub> determination were also taken from intact, healthy (untreated control) females after the beginning of heat (<i>n</i> = 5), or 9–21 days after, with hCG induced ovulation (<i>n</i> = 6), or out of breeding season (<i>n</i> = 3). Before treatment, all three alopecic ferrets showed elevated E<sub>2</sub> concentrations (99.45–139.9 pmol/l) similar to the untreated control females in oestrous (61.6–123.02 pmol/l) (<i>P</i> = 0.229). Some weeks after the deslorelin administration, the hair of these ferrets began to grow again and the elevated E<sub>2</sub> concentrations significantly decreased compared to the pre-treatment values (<i>P</i> = 0.035). E2 concentrations reached the basal level (12.89–16.08 pmol/l) typical for that of the untreated control females in anoestrus or in luteal phase (12.0–30.58 pmol/l) (<i>P</i> = 0.137). All treated ferrets were examined again 19–21 months after implant insertion (the implant still being present) and all of them had normal hair and were clinically healthy. These observations prove that deslorelin can suppress the E<sub>2</sub> production of NHA, and is therefore a useful tool in the therapy of hormonal alopecia neutered ferrets.

A note on the effect of melatonin feeding on the initiation of ovarian activity and on plasma prolactin levels in lactating and non-lactating red deer hinds

1985 ◽  
Vol 40 (3) ◽  
pp. 515-518 ◽  
Author(s):  
Rachel Nowak ◽  
R. N. Elmhirst ◽  
R. G. Rodway
Keyword(s):  
Detection Limit ◽  
Corpus Luteum ◽  
Red Deer ◽  
Inhibitory Effect ◽  
Ovarian Activity ◽  
Plasma Prolactin ◽  
Melatonin Treatment ◽  
Plasma Progesterone ◽  
Blood Samples

ABSTRACTMelatonin was fed daily at 14.00 h to eight non-lactating and six lactating hinds. Feeding was begun on 27 July 1983 (day 1) and continued until 21 September (day 57). Six non-lactating hinds were used as controls. Blood samples were taken about every 10 days from day 42 until day 73. Plasma progesterone and prolactin were determined by radioimmunoassay. Progesterone values of greater than 0·63 μg/1 were taken to indicate the presence of a corpus luteum and that the animal had ovulated. In the melatonintreated, non-lactating group seven of the eight hinds showed ovarian activity compared with two of the six controls (P < 0·01). None of the lactating hinds treated with melatonin showed evidence of ovarian activity. In both the lactating and non-lactating hinds treated with melatonin, prolactin levels were never greater than the detection limit of the assay (7·4 μg/l), while, in the control hinds mean prolactin levels were elevated on all but the last sampling day. It is, therefore, possible to induce early ovarian activity in non-lactating red deer hinds by feeding melatonin. However, although melatonin treatment similarly depressed plasma prolactin levels in both lactating and non-lactating hinds, it was unable to overcome the inhibitory effect of lactation on reproduction.

Can the transition into anoestrus in the ewe be accounted for solely by insufficient tonic LH secretion?

1985 ◽  
Vol 106 (1) ◽  
pp. 55-60 ◽  
Author(s):  
S. J. Legan ◽  
R. L. Goodman ◽  
K. D. Ryan ◽  
D. L. Foster ◽  
F. J. Karsch
Keyword(s):  
Corpus Luteum ◽  
Breeding Season ◽  
Negative Feedback ◽  
Ovarian Response ◽  
Ovulatory Cycle ◽  
Serum Lh ◽  
Transient Rise ◽  
Lh Secretion ◽  
Sustained Increase

ABSTRACT It has been proposed that a seasonal increase in oestradiol negative feedback elicits anoestrus by preventing a key step in the preovulatory sequence of endocrine events, namely a sustained increase in tonic LH secretion. In the present study we compared the patterns of serum LH, FSH, oestradiol and progesterone after regression of the last corpus luteum of the breeding season, with their respective patterns during an ovulatory cycle in the late breeding season (samples obtained every 4 h from eight ewes). After regression of the last corpus luteum of the breeding season, serum LH and oestradiol showed distinct deviations from their respective late breeding season patterns. The rise in tonic LH secretion was curtailed. Further, there were no marked increases in oestradiol, despite a distinct, although brief, tonic LH rise; thus there were no gonadotrophin surges. If the hypothesis that the transition into anoestrus is caused solely by insufficient tonic LH secretion were correct, the brief increase in LH should have induced a transient rise in oestradiol. Since this was not the case, these results suggest that a decreased ovarian response to LH may also contribute to the termination of oestrous cyclicity at the transition to anoestrus. J. Endocr. (1985) 106, 55–60

THE MECHANISM OF THE INDUCTION OF OVULATION BY OESTROGENS

1965 ◽  
Vol 33 (3) ◽  
pp. 491-499 ◽  
Author(s):  
F. DÖCKE ◽  
G. DÖRNER
Keyword(s):  
Effective Dose ◽  
Corpus Luteum ◽  
Anterior Pituitary ◽  
Anterior Hypothalamus ◽  
Female Rats ◽  
Main Site ◽  
Induction Of Ovulation ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Electrolytic Lesions

SUMMARY To study the positive feed-back mechanism by which oestrogen induces corpus luteum formation, electrolytic lesions were placed in different parts of the anterior hypothalamus of prepubertal female rats which were then injected with oestradiol benzoate. Ovarian luteinization did not occur when the main parts of the suprachiasmatic nuclei or of the medial preoptic area had been destroyed. Oestradiol benzoate was implanted stereotaxically into the brain and the anterior pituitary of immature female rats. Whereas 1/25 of the subcutaneously effective dose had to be implanted into the anterior hypothalamus, 1/100 of the peripherally effective dose introduced into the adenohypophysis was sufficient to induce corpus luteum formation in most of the treated animals. The results suggest that, although the anterior hypothalamus is necessary for this positive feed-back mechanism, the anterior pituitary may be the main site of action of oestrogen. Oestrogen may increase the hypophysial sensitivity to the hypothalamic gonadotrophin-releasing factor. Thus an enhanced gonadotrophin secretion may result, sufficient for the induction of ovulation. The possibility is discussed that this positive feed-back mechanism is also essential for the induction of ovulation in women.

Effects of immunization against recombinant bovine inhibin α subunit on circulating concentrations of gonadotrophins in ewes

1989 ◽  
Vol 120 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J. K. Findlay ◽  
B. Doughton ◽  
D. M. Robertson ◽  
R. G. Forage
Keyword(s):  
Breeding Season ◽  
Untreated Control ◽  
Luteal Phase ◽  
Plasma Concentrations ◽  
Follicular Phase ◽  
Ovulation Rate ◽  
Α Subunit ◽  
Keyhole Limpet Haemocyanin ◽  
Fourfold Increase ◽  
Breeding Seasons

ABSTRACT Immunization of ewes against a pure recombinant preparation of the α subunit of bovine inhibin (α-bI) resulted in a three- to fourfold increase in ovulation rate, associated with antibodies in plasma recognizing pure native 31 kDa inhibin. The aim of this study was to examine the effects of this immunization on basal and GnRH-stimulated plasma concentrations of FSH and LH in ewes during the anoestrous and breeding seasons. The groups were untreated control ewes (n = 5), control ewes treated with keyhole limpet haemocyanin (KLH alone, n = 4), ewes treated with α-bI alone (n = 4) and α-bI–KLH conjugate-treated ewes (n = 3). There were no effects of immunization on basal FSH or LH in anoestrous ewes, despite the presence of antibodies recognizing 31 kDa inhibin. In the breeding season, immunization against α-bI resulted in increased basal (follicular phase, P < 0·1; luteal phase P < 0·05) and GnRH-stimulated (follicular phase only, P < 0·001) release of FSH, but not LH. The data are compatible with the hypotheses that the increase in ovulation rate in immunized ewes is due to an increase in circulating FSH concentrations and that inhibin may only have a major peripheral influence on FSH in sheep during the breeding season. Journal of Endocrinology (1989) 120, 59–65

scholarly journals Local changes in blood flow within the preovulatory follicle wall and early corpus luteum in cows

Reproduction ◽  
2003 ◽  
pp. 759-767 ◽  
Author(s):  
TJ Acosta ◽  
KG Hayashi ◽  
M Ohtani ◽  
A Miyamoto
Keyword(s):  
Blood Flow ◽  
Corpus Luteum ◽  
Plasma Concentrations ◽  
Maximum Velocity ◽  
Initial Increase ◽  
Preovulatory Follicle ◽  
Lh Surge ◽  
Functional Changes ◽  
Induced Ovulation ◽  
Doppler Image

Haemodynamic changes are involved in the cyclic remodelling of ovarian tissue that occurs during final follicular growth, ovulation and new corpus luteum development. The aim of this study was to characterize the real-time changes in the blood flow within the follicle wall associated with the LH surge, ovulation and corpus luteum development in cows. Normally cyclic cows with a spontaneous ovulation (n = 5) or a GnRH-induced ovulation (n = 5) were examined by transrectal colour and pulsed Doppler ultrasonography to determine the area and the time-averaged maximum velocity (TAMXV) of the blood flow within the preovulatory follicle wall and the early corpus luteum. Ultrasonographic examinations began 48 h after a luteolytic injection of PGF(2alpha) analogue was given at the mid-luteal phase of the oestrous cycle. Cows with spontaneous ovulation were scanned at 6 h intervals until ovulation occurred. Cows with GnRH-induced ovulation were scanned just before GnRH injection (0 h), thereafter at 0.5, 1, 2, 6, 12, 24 h and at 24 h intervals up to day 5. Blood samples were collected at the same time points for oestradiol, LH and progesterone determinations. Cows with both spontaneous and GnRH-induced ovulation showed a clear increase in the plasma concentration of LH (LH surge) followed by ovulation 26-34 h later. In the colour Doppler image of the preovulatory follicle, the blood flow before the LH surge was detectable only in a small area in the base of the follicle. An acute increase in the blood flow velocity (TAMXV) was detected at 0.5 h after GnRH injection, synchronously with the initiation of the LH surge. At 12 h after the LH surge, the plasma concentrations of oestradiol decreased to basal concentrations. The TAMXV remained unchanged after the initial increase until ovulation, but decreased on day 2 (12-24 h after ovulation). In the early corpus luteum, the blood flow (area and TAMXV) gradually increased in parallel with the increase in corpus luteum volume and plasma progesterone concentration from day 2 to day 5, indicating active angiogenesis and normal luteal development. Collectively, the complex structural, secretory and functional changes that take place in the ovary before ovulation are closely associated with a local increase in the blood flow within the preovulatory follicle wall. The result of the present study provides the first visual information on vascular and blood flow changes associated with ovulation and early corpus luteum development in cows. This information may be essential for future studies involving pharmacological control of blood flow and alteration of ovarian function.

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