Pregnancy in a marsupial, the Tasmanian pademelon (Thylogale billardierii)

1999 ◽  
Vol 11 (3) ◽  
pp. 175 ◽  
Author(s):  
R. W. Rose ◽  
J. A. A. Horak ◽  
A. D. Shetewi ◽  
S. M. Jones
Keyword(s):  
Corpus Luteum ◽  
Reproductive Biology ◽  
Plasma Concentrations ◽  
Tammar Wallaby ◽  
Reproductive Organs ◽  
Model Species ◽  
Histological Changes ◽  
Plasma Progesterone ◽  
Embryonic Growth ◽  
Background Data

The Tasmanian pademelon, Thylogale billardierii, is a medium-sized wallaby that adapts well to captivity and, unlike the well-studied tammar wallaby, is capable of breeding all year round. It may, there-fore, be a useful model species for research into the reproductive biology of macropod marsupials. This paper presents necessary background data on histological changes in the reproductive organs and the rate of embryonic growth during gestation in T. billardierii. After Day 4 RPY (removal of young from the pouch) the gravid and non-gravid uteri differ significantly in some histological parameters. The corpus luteum becomes active by Day 6 RPY and is fully developed by Day 14 RPY; it begins to degenerate from Day 19 RPY. Plasma progesterone concentrations through gestation follow a pattern similar to that in the tammar wallaby. There is an early, smaller, peak at Day 5 RPY, with plasma concentrations of progesterone then falling until the larger pre-partum peak occurs several days before birth.

scholarly journals Anatomical and histological changes during the oestrous cycle in the mare

1941 ◽  
Vol 130 (858) ◽  
pp. 1-23 ◽  
Keyword(s):  
Corpus Luteum ◽  
Reproductive Organs ◽  
Oestrous Cycle ◽  
Maximum Diameter ◽  
Histological Changes ◽  
Graafian Follicle ◽  
Heat Period ◽  
To Come ◽  
Time Required ◽  
Dominant Part

The mares chosen for the investigation of the changes in the reproductive organs during the oestrous cycle were kept under observation for some time before they were killed. The duration of the heat period in these animals was 7 days and the length of the dioestrus was 16 days. Ovulation takes place at about a day before the end of oestrus. The size of the ovary during the oestrous cycle is chiefly influenced by the growing Graafian follicle. The number of follicles present at different stages varies greatly. The numerous small follicles present at the beginning of oestrus disappear later in the cycle; it is suggested that this may be due to the lack of follicle-stimulating hormone. The colour of the corpus luteum varies greatly at different stages of the cycle. The rupture of the follicle is associated with some bleeding. The active stage of the corpus luteum is very short, and the maximum diameter of the corpus luteum seems to be always below that of the Graafian follicle. The greater development of the Graafian follicle, with its secretion of oestrin, in the mare leads to its playing a more important role than in the cow and the sow, in which species the corpus luteum takes a m ore dominant part in the cycle. It appears that the much longer oestrus in the mare than in the cow is due to the longer time required by the follicle to come to the surface and to break through. This is probably due to the peculiar structure of the ovary in the mare, since the ovulation, which is spontaneous, can only occur in the small ovulation fossa. No pronounced secretion stage occurs during oestrus in the Fallopian tubes.

scholarly journals Morphological features and vascularization study of caprine cyclic corpus luteum

2010 ◽  
Vol 30 (4) ◽  
pp. 351-357 ◽  
Author(s):  
Maria Tereza M. Miranda-Moura ◽  
Vanessa Uemura da Fonseca ◽  
Naisandra Bezerra da Silva ◽  
Maria de Lourdes Freitas ◽  
Osiel Benedito de Almeida ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Estrous Cycle ◽  
Plasma Concentrations ◽  
Cycle Phase ◽  
Vascular Density ◽  
Endocrine Gland ◽  
Plasma Progesterone ◽  
Meaningful Relationship ◽  
Commercial Kits ◽  
The Right

Corpus luteum is a temporary endocrine gland that regulates either the estrous cycle and pregnancy. It presents extreme dependency on the adequate blood supply. This work aims to evaluate goat corpus luteum (CL) vascular density (VD) over the estrous cycle. For that purpose, 20 females were submitted to estrus synchronization/ovulation treatment using a medroxyprogesterone intra-vaginal sponge as well as intramuscular (IM) application of cloprostenol and equine chorionic gonadotrophine (eCG). After sponge removal, estrus was identified at about 72hs. Once treatment was over, female goats were then subdivided into 4 groups (n=5 each) and slaughtered on days 2, 12, 16 and 22 after ovulation (p.o). Ovaries were collected, withdrawn and weighted. CL and ovaries had size and area recorded. Blood samples were collected and the plasma progesterone (P4) was measured through RIA commercial kits. The VD was 24.42±6.66, 36.26±5.61, 8.59±2.2 and 3.97±1.12 vessels/mm² for days 2, 12, 16 and 22 p.o, respectively. Progesterone plasma concentrations were 0.49±0.08, 2.63±0.66, 0.61±0.14 and 0.22±0.04ng/ml for days 2, 12, 16 e 22 p.o, respectively. Studied parameters were affected by the estrous cycle phase. Values greater than 12 p.o were observed. In the present work we observed that ovulation occurred predominantly in the right ovary (70% of the animals), which in turn presented bigger measures than the contra lateral one. There is a meaningful relationship between the weight and size of the ovary and these of CL (r=0.87, r=0.70, respectively, p<0.05). It is possible to conclude that morphology of goat's ovaries and plasma progesterone concentration changed according to estrous cycle stages. We propose these parameters can be used as indicators of CL functional activity.

Effects of the ovary, sucking stimulus and season on the pattern of LH and FSH release in the female tammar, Macropus eugenii

1992 ◽  
Vol 4 (1) ◽  
pp. 25 ◽  
Author(s):  
LA Hinds ◽  
PJ Diggle ◽  
CH Tyndale-Biscoe
Keyword(s):  
Corpus Luteum ◽  
Breeding Season ◽  
Ovarian Tissue ◽  
Plasma Concentrations ◽  
Low Frequency ◽  
Tammar Wallaby ◽  
Pulse Frequency ◽  
Sequential Effects ◽  
Macropus Eugenii ◽  
Bilateral Ovariectomy

The sequential effects of removal of the corpus luteum, removal of the non-luteal ovary and sucking stimulus and the effects of season of the year on the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) have been determined in the tammar wallaby, Macropus eugenii. Plasma concentrations of LH and FSH were measured at 15 min intervals for 6 h in eight animals at four successive times in the breeding season (lactational quiescence); (A) while they were intact and lactating, (B) 10 days after removal of the ovary bearing the quiescent corpus luteum, (C) 21 days after bilateral ovariectomy and (D) 21 days after removal of the sucking stimulus, and (E) in the following non-breeding season (seasonal quiescence). Single blood samples were taken twice weekly during lactational quiescence. In the presence of ovarian tissue, basal concentrations of LH were low (0.94 ng mL-1) with pulses of low magnitude (1.3 ng mL-1) and low frequency (1.4 pulses per 6 h). There was no response to luteectomy but all three parameters increased after bilateral ovariectomy. Removal of the sucking stimulus affected the LH pulse frequency but seasonal differences were not evident. The pattern of release of FSH was not pulsatile. There was no response to luteectomy in basal concentrations of FSH but these rose significantly after bilateral ovariectomy (P less than 0.001) in lactational quiescence. There was no effect of removing the sucking stimulus but in seasonal quiescence concentrations were higher. The results indicate that non-luteal ovarian tissue is essential for the negative-feedback effects on LH and FSH secretion, that the pattern of release of LH, but not FSH, is pulsatile, and that there is no marked seasonal change in hypothalamo-hypophysial activity.

scholarly journals WOMEN IN REPRODUCTIVE SCIENCE: Reproduction down under

Reproduction ◽  
2019 ◽  
Vol 158 (6) ◽  
pp. F127-F137
Author(s):  
Marilyn B Renfree
Keyword(s):  
Comparative Genomics ◽  
Reproductive Biology ◽  
International Research ◽  
Scientific Community ◽  
Tammar Wallaby ◽  
Model Species ◽  
Signalling Molecules ◽  
Disciplinary Expertise ◽  
Reproductive Science ◽  
Conservation And Management

Australia is home to a unique assembly of mammals – the marsupials and monotremes. Despite this uniqueness, they have been largely ignored by the biomedical scientific community, and yet study of marsupials has contributed to modern research on reproduction, development, evolution, conservation, molecular and comparative genomics. My lifetime passion for these long-neglected Australian fauna has led to unexpected discoveries and insights that challenged assumptions and opened up new areas of international research. I used a range of disciplinary expertise to pursue the study of these unique mammals. My main experimental species has been the tammar wallaby that I have used as a model species to investigate and understand not only biomedical problems but also to provide knowledge that is critical for the continued conservation and management of Australia’s dwindling native mammals. This model provided more than a few surprises for me and my wonderful team of students, post-docs and collaborators about how hormones, genes and signalling molecules control reproductive biology and development in a wider context as well as how the interactions of the environment with mother and conceptus, with mother and fetus and mother and young ultimately control most aspects of successful reproduction in mammals.

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.

scholarly journals Growth of the corpus luteum and its progesterone content during pregnancy in the tammar wallaby, Macropus eugenii

Reproduction ◽  
1979 ◽  
Vol 57 (1) ◽  
pp. 131-136 ◽  
Author(s):  
M. B. Renfree ◽  
S. W. Green ◽  
I. R. Young
Keyword(s):  
Corpus Luteum ◽  
Tammar Wallaby ◽  
Macropus Eugenii

PLASMA PROLACTIN AND PROGESTERONE RESPONSES TO MATING ARE ALTERED IN AGED RATS

1981 ◽  
Vol 90 (2) ◽  
pp. 179-191 ◽  
Author(s):  
S. HENDRICKS ◽  
C. A. BLAKE
Keyword(s):  
Plasma Concentrations ◽  
External Jugular Vein ◽  
Female Rats ◽  
Plasma Prolactin ◽  
Aged Rats ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Plasma Progesterone ◽  
The One ◽  
The Right

The effects of varying amounts of copulatory stimulation on patterns of plasma concentrations of prolactin and progesterone were evaluated in 3- and 12-month-old female rats. The 12-month-old group included rats which still exhibited oestrous cycles and rats in persistent vaginal oestrus (PVO). The extent of copulatory stimulation was defined by the number of intromissions received during mating: ≤5,15 or > 50. Blood samples were drawn over the 8 days after mating through a cannula inserted into the right external jugular vein. Plasma from the samples was assayed for prolactin and progesterone. In aged but still cyclic rats, pregnancy rates were positively correlated with the number of intromissions received during mating. Only one rat in PVO became pregnant. All animals which became pregnant and rats in PVO which, after mating, exhibited a disruption of the pattern of PVO, showed the nocturnal surge of plasma prolactin characteristic of pregnant and pseudopregnant rats. While these surges persisted until day 8 after mating in pregnant animals, they were absent by this time in the rats in PVO. Prolactin surges were present in some but not all of the aged rats which did not become pregnant. Progesterone concentrations were raised in all pregnant animals except the one pregnant rat in PVO and, while not related to the number of intromissions, concentrations were higher 8 days after mating in young compared with those in aged pregnant rats. Plasma progesterone was low in rats in PVO regardless of disruption of the pattern of PVO. We have concluded that the failure of limited copulatory stimulation to induce pregnancy in older rats results, at least in part, from its failure to initiate nocturnal prolactin surges. Nevertheless, our data suggest that matings which are not experimentally limited should provide ample stimulation to establish such surges. Although reduced plasma concentrations of prolactin and progesterone at pro-oestrus and reduced plasma progesterone through part of gestation may contribute to decreasing fertility in aged rats, other unidentified factors appear to be involved in mediating the capacity of extensive copulatory stimulation to induce pregnancy in these animals.

Sign in / Sign up

Export Citation Format

Share Document