12 PHARMACOLOGICAL STIMULATION OF OVULATION IN THE BLACK FLYING-FOX (PTEROPUS ALECTO)

Artificial insemination (AI) involves the accurate detection of oestrus, the ability to pharmacologically induce ovulation, or both. This is particularly important in flying-foxes (Pteropus spp.) that do not have an overt behavioural oestrus. Pregnant mare serum gonadotropin (PMSG) stimulates folliculogenesis and ovulation in the Little Red Flying-fox (P. scapulatus; Towers PA and Martin L 1985 Proc. Aust. Soc. Reprod. Biol. 17, 115). In this study, a dose rate of 15 IU PMSG was used. Our study investigated if 15 IU PMSG would sufficiently induce ovulation in the larger, Black Flying-fox (P. alecto) or if a higher dose (30 IU) would be necessary. Before the mating season, a single injection of PMSG (Folligon®, Intervet Australia Pty Ltd, Bendigo East, Australia) was administered i.m. to eight adult females at 15 IU (n = 4) or 30 IU (n = 4) on Day 0. On Day 4, semen was collected by electro-ejaculation from adult males and inseminated intravaginally into females under isoflurane (Forthane®, Abbott Australasia Pty Ltd, Sydney, Australia) anaesthesia. Ovaries and reproductive tracts were surgically removed on Day 6, fixed, serially sectioned and stained using Gomori’s Stain. Histological sections were examined for evidence of ovarian activity and the presence of ova and spermatozoa in the reproductive tracts. Preliminary observations showed evidence of ovulation in both groups in the form of at least one CL in either ovary and an ovum in the ipsilateral oviduct or uterine horn. Ovaries of females stimulated with 30 IU PMSG differed noticeably from those treated with 15 IU in containing multiple, large, collapsed luteinized follicles with retained oocytes. Vascularization and glandular hypertrophy of the endometrium was also more evident in the higher dose group. No spermatozoa were observed in any of the excised tracts. These results suggest that whereas both doses of PMSG induce ovulation, the administration of 30 IU PMSG may over-stimulate the ovaries. This, in turn, could lead to an unphysiological environment for successful fertilization and embryonic development. A dose level of 15 IU or slightly above may be sufficient for subsequent attempts to stimulate folliculogenesis and ovulation in P. alecto. The absence of spermatozoa suggests that the site of insemination, the number of spermatozoa inseminated, or both requires further investigation if AI is to be successfully implemented in these species. We conclude that the ovarian responses to PMSG indicate that pharmacological induction of ovulation can be successfully achieved and thereby utilized in AI programs of endangered Pteropus species.

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Ovarian remnant syndrome: revascularization of free-floating ovarian tissue in the feline abdominal cavity

Journal of the American Animal Hospital Association ◽

10.5326/15473317-37-3-290 ◽

2001 ◽

Vol 37 (3) ◽

pp. 290-296 ◽

Cited By ~ 18

Author(s):

GA DeNardo ◽

K Becker ◽

NO Brown ◽

S Dobbins

Keyword(s):

Histopathological Examination ◽

Ovarian Tissue ◽

Abdominal Cavity ◽

Ovarian Activity ◽

Corpora Lutea ◽

Intact Female ◽

Pregnant Mare Serum Gonadotropin ◽

Vaginal Cytology ◽

Serum Gonadotropin ◽

Stimulation Of

Nine, healthy, intact female domestic shorthair cats were ovariohysterectomized. At the time of surgery and following removal, the major portion of one ovary was loosely sutured to the mesentery and replaced in the abdominal cavity. Six months later, an abdominal laparotomy was performed in order to retrieve the ovarian remnants. Histopathological examination of the remnants showed viable tissue and evidence of ovarian follicles or corpora lutea in eight of nine (88.9%) cats. The ninth ovarian remnant was atrophied and fibrotic. Measurement of serum estradiol and progesterone, vaginal cytology, and stimulation of estrus and ovulation with a protocol using pregnant mare serum gonadotropin (PMSG) followed by human chorionic gonadotropin (hCG) were unreliable indicators of ovarian activity in this study. Revitalization of an ovarian remnant was shown to occur in the absence of surgical implantation.

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Ovarian activity in progesterone treated mares following administration of pregnant mare serum gonadotropin

Theriogenology ◽

10.1016/0093-691x(82)90090-5 ◽

1982 ◽

Vol 17 (3) ◽

pp. 305-311 ◽

Cited By ~ 7

Author(s):

J.E. Dinger ◽

E.E. Noiles ◽

M.J.L. Bates

Keyword(s):

Ovarian Activity ◽

Pregnant Mare Serum Gonadotropin ◽

Serum Gonadotropin

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Interaction of PGF2α with prolactin on the release of cyclic AMP and progesterone from the isolated perfused ovary of the pregnant mare serum gonadotropin-treated rat

Acta Endocrinologica ◽

10.1530/acta.0.1130410 ◽

1986 ◽

Vol 113 (3) ◽

pp. 410-417 ◽

Cited By ~ 2

Author(s):

Jan Sogn ◽

Gun Abrahamsson ◽

Per O. Janson

Keyword(s):

Cyclic Amp ◽

Inhibitory Effect ◽

Pregnant Mare Serum Gonadotropin ◽

Progesterone Secretion ◽

Site Of Action ◽

Serum Gonadotropin ◽

Rat Ovary ◽

Camp Formation ◽

Isolated Rat ◽

Stimulation Of

Abstract. A newly developed model for perfusion of the isolated rat ovary was employed to study the interactions of Prl with PGF2α in respect to the effects of LH on cAMP formation and progesterone production in the 5 day old corpus luteum of the PMSG-treated rat. An inhibitory effect of PGF2α on both basal and LH stimulated progesterone secretion was found. This block also involved inhibition of the ovarian cAMP release which was not associated with a reduction of the flow of the medium to the ovary. When Prl was present in the medium the PGF2α block of LH-induced cAMP release was reversed. However, Prl failed to restore block of LH stimulation of progesterone secretion in 4 out of 9 experiments, indicating an additional site of action of PGF2α distal to the cAMP in these experiments.

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Stimulation of seasonally anovular mule ewes by rams

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600010503 ◽

1989 ◽

Vol 1989 ◽

pp. 57-57

Author(s):

H. F. Ibraheem ◽

M. E. King ◽

J. S. M. Hutchinson ◽

G. J. Gunn ◽

L. Taylor ◽

...

Keyword(s):

Ovarian Activity ◽

Seasonal Activity ◽

Short Supply ◽

Serum Gonadotropin ◽

Group 3 ◽

Group 5 ◽

Group 2 ◽

Activity Groups ◽

The Uk ◽

Stimulation Of

Early lamb production is a specialist enterprise in which profitability is highly dependent on getting all the lambs sold while prices are still high in Spring when lamb is in short supply. This involves lambing in late December/early January. Hence ewes must be mated in August. Conventionally in the UK, this has been achieved by the use of progesterone-impregnated sponges and pregnant mare's serum gonadotropin (PMSG). The ram effect is a powerful technique for the control of sheep reproduction. The objective of the present study was to reinvestigate the value of teasers for the stimulation of seasonal activity in the ewe.125 (2-3 yr) Mule ewes (Blue-faced Leicester x Swaledale or Blackface), isolated from rams for two months, were used to investigate the effect of different durations of teasing on the stimulation of seasonal activity. Groups of 25 ewes were exposed to either teaser vasectomised rams and teaser ovariectomised ewes (induced into behavioural oestrus by an intramuscular injection of 0.2 mg of oestradiol benzoate) for 1 month (group l), 3 weeks (group 2) and 2 weeks (group 3); or vasectomised rams only for 2 weeks (group4); or left untreated (group 5). At the imposition of treatments, groups were isolated from each other and from contact with other 3heep by a distance of at least 1 km. Plasma progesterone was measured twice weekly on 8 animals, per group to determine ovarian activity.

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A note on conception rates and litter sizes following the intrauterine insemination of ewes at an induced oestrus during seasonal anoestrus

Animal Science ◽

10.1017/s0003356100004839 ◽

1990 ◽

Vol 50 (2) ◽

pp. 379-382 ◽

Cited By ~ 6

Author(s):

R. P. Aitken ◽

J. M. Wallace ◽

J. J. Robinson

Keyword(s):

Intrauterine Insemination ◽

Fertilization Rate ◽

Uterine Horn ◽

Ovulation Rate ◽

Plasma Progesterone ◽

Pregnant Mare Serum Gonadotropin ◽

Vaginal Pessary ◽

Serum Gonadotropin ◽

Viable Sperm ◽

High Fertilization

Priming with a progestagen-impregnated vaginal pessary followed by an injection of 750 i.u. pregnant mare serum gonadotropin at pessary withdrawal was used to induce oestrus and ovulation during anoestrus (13 June, latitude 57°N) in 58 Border Leicester × Scottish Blackface ewes that had lambed previously in late March/early April. At 54 to 58 h after pessary withdrawal the uterus of each ewe was viewed by laparoscopy and 50 × 106 viable sperm deposited into each uterine horn. Mean ovulation rate was 2·9 (s.d. 0·12; range 1 to 5). Plasma progesterone concentrations remained >1·5 μg/l in 54 (93%) of the ewes until at least day 21 after insemination implying a high fertilization rate. After allowing for three ewes that were observed to abort between 39 and 55 days after insemination and another three, carrying nine normally developed lambs, that died between 102 and 136 days of gestation, 40 of the remaining 48 ewes (i.e. 69% of the original 58) produced 76 viable lambs in early November. These conception and lambing rates obtained following the intrauterine insemination of 100× 106 viable sperm per ewe are more than double those obtained following natural mating or conventional cervical insemination with four times the number of viable sperm and imply that intrauterine insemination may enhance lamb production from ewes induced to breed during seasonal anoestrus.

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The Fine Structure of Rat Granulosa Cell Cultures Correlated with Progestin Secretion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073209 ◽

1973 ◽

Vol 31 ◽

pp. 552-553

Author(s):

T. M. Crisp ◽

F.R. Denys

Keyword(s):

Fine Structure ◽

Granulosa Cell ◽

Cell Cultures ◽

Single Injection ◽

Surrounding Medium ◽

Petri Dish ◽

Female Rats ◽

Vaginal Smear ◽

Immature Female ◽

Serum Gonadotropin

The purpose of this paper is to present observations on the fine structure of rat granulosa cell cultures grown in the presence of an adenohypophyseal explant and to correlate the morphology of these cells with progestin secretion. Twenty-six day old immature female rats were given a single injection of 5 IU pregnant mares serum gonadotropin (PMS) in order to obtain ovaries with large vesicular follicles. At 66 hrs. post-PMS administration (estrus indicated by vaginal smear cytology), the ovaries were removed and placed in a petri dish containing medium 199 and 100 U penicillin/streptomycin (P/S)/ml. Under a 20X magnification dissecting microscope, some 5-8 vesicular follicles/ovary were punctured and the granulosa cells were expressed into the surrounding medium. The cells were transferred to centrifuge tubes and spun down at 1000 rpm for 5 mins.

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Enhancement of Plasminogen Binding to U937 Cells and Fibrin by Complestatin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655921 ◽

1997 ◽

Vol 77 (01) ◽

pp. 137-142 ◽

Cited By ~ 20

Author(s):

Kiyoshi Tachikawa ◽

Keiji Hasurni ◽

Akira Endo

Keyword(s):

Binding Site ◽

Binding Affinity ◽

Blood Cells ◽

Aminocaproic Acid ◽

U937 Cells ◽

Biochemical Basis ◽

Equilibrium Binding ◽

Pharmacological Stimulation ◽

Endogenous Fibrinolysis ◽

Stimulation Of

SummaryPlasminogen binds to endothelial and blood cells as well as to fibrin, where the zymogen is efficiently activated and protected from inhibition by α2-antiplasmin. In the present study we have found that complestatin, a peptide-like metabolite of a streptomyces, enhances binding of plasminogen to cells and fibrin. Complestatin, at concentrations ranging from 1 to 5 μM, doubled 125I-plasminogen binding to U937 cells both in the absence and presence of lipoprotein(a), a putative physiological competitor of plasminogen. The binding of 125I-plasminogen in the presence of complestatin was abolished by e-aminocaproic acid, suggesting that the lysine binding site(s) of the plasminogen molecule are involved in the binding. Equilibrium binding analyses indicated that complestatin increased the maximum binding of 125I-plasminogen to U937 cells without affecting the binding affinity. Complestatin was also effective in increasing 125I-plasminogen binding to fibrin, causing 2-fold elevation of the binding at ~1 μM. Along with the potentiation of plasminogen binding, complestatin enhanced plasmin formation, and thereby increased fibrinolysis. These results would provide a biochemical basis for a pharmacological stimulation of endogenous fibrinolysis through a promotion of plasminogen binding to cells and fibrin.

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