Delayed ovulation and parturition in a viviparous alpine lizard (Niveoscincus microlepidotus): morphological data and plasma steroid concentrations

2002 ◽  
Vol 14 (1) ◽  
pp. 43 ◽  
Author(s):  
J. E. Girling ◽  
S. M. Jones ◽  
R. Swain
Keyword(s):  
Reproductive Cycle ◽  
Early Pregnancy ◽  
Post Partum ◽  
Maximum Size ◽  
Morphological Data ◽  
Monthly Basis ◽  
Plasma Progesterone ◽  
Plasma Oestradiol ◽  
Winter Hibernation ◽  
Detailed Picture

The southern snow skink, Niveoscincus microlepidotus, exhibits an unusual biennial reproductive cycle with an extended gestation period of approximately 1 year. Morphological data were gathered on a monthly basis, providing a detailed picture of the reproductive cycle. Vitellogenesis begins in spring, immediately after parturition. Maximum follicular diameter is reached before the winter hibernation period and ovulation occurs the following spring. Embryos are fully developed and reach maximum size by early autumn. Yolk reserves are depleted before winter. Birth of between one and four young occurs the following spring. Plasma progesterone concentrations are low (2.7 ± 0.9 ng mL–1) in post-partum females, begin to rise in autumn in vitellogenic females and peak (38.5 ± 7.9 ng mL–1) in pre-ovulatory females after hibernation. Concentrations are high (15.4 ± 5.9 ng mL–1) in early pregnancy and decline to basal levels before winter and well before birth in spring. Plasma oestradiol concentrations peak during vitellogenesis (1.0 ± 0.3 ng mL–1) and decline to basal levels during pregnancy (0.2 ± 0.03 ng mL–1). A second oestradiol peak occurs before parturition (0.7 ± 0.2 ng mL–1). Thus, functional completion of vitellogenesis and gestation is achieved by autumn in successive years. The mechanisms that defer ovulation and parturition by a further six months are unknown.

SEQUENTIAL CHANGES IN PLASMA PROGESTERONE IN THE COW DURING THE ESTROUS CYCLE, PREGNANCY, AT PARTURITION, AND POST-PARTUM

1972 ◽  
Vol 52 (4) ◽  
pp. 645-658 ◽  
Author(s):  
H. A. ROBERTSON
Keyword(s):  
Estrous Cycle ◽  
Early Pregnancy ◽  
Luteal Phase ◽  
Post Partum ◽  
Progesterone Concentration ◽  
Cyclic Activity ◽  
Gradual Decline ◽  
Plasma Progesterone ◽  
Peripheral Plasma ◽  
Estrous Behavior

The progesterone concentration in peripheral plasma has been measured sequentially in individual cows during the estrous cycle, gestation, at parturition, and post-partum. During the estrous cycle the concentration was lowest just before, during, and just after estrus when the level (0.1–0.4 ng/ml) was similar to that found in three ovariectomized cows. The concentration commenced to rise on the 4th–6th day (day of estrus = 1st day), reached a peak of 3–6 ng/ml on the 11th–13th day, and dropped rapidly over a 24–48-hr period to a basal value 24–72 hr before the next estrus. In early pregnancy, the plasma progesterone concentration was similar to the maximum levels found during the luteal phase of the estrous cycle. Between 90 and 150 days there was an indication of a decline to a relatively low plasma progesterone concentration followed by a variable rise. Prior to parturition, there was a gradual decline over a period of 35–70 days reaching a level of <2.0 ng/ml the day before parturition. Following parturition, the level remained at <0.5 ng/ml until the first sign of the resumption of cyclic activity. The time for this to occur was very variable (20–>60 days). Although not conclusive, the evidence favors the view that for estrous behavior to occur, estrus must be preceded by luteal activity. The discharge of mucus can occur without previous luteal activity.

Studies on plasma progesterone concentrations and fertility in Friesland dairy cows during the post-partum period

1981 ◽  
Vol 97 (3) ◽  
pp. 649-654 ◽  
Author(s):  
D. H. Holness ◽  
G. W. Sprowson ◽  
Carole Sheward ◽  
Amanda Geel
Keyword(s):  
Dairy Cows ◽  
Early Pregnancy ◽  
Post Partum ◽  
Ovarian Activity ◽  
Plasma Progesterone ◽  
Low Concentrations ◽  
The Mean ◽  
Post Partum Period ◽  
Embryo Loss

SUMMARYPlasma progesterone concentrations were monitored in 69 lactating Friesland dairy cows during the post-partum period. Cyclic ovarian activity resumed in most cows within 40 days of calving. Forty-eight per cent of cows remained pregnant to their first insemination, 41% returned to oestrus before day 30 after insemination, and a further 11% returned to oestrus between days 30 and 88 after insemination.The mean of progesterone values on days 11 to 4 before insemination tended to be higher in cows that conceived than in cows that did not conceive. These differences were signficant on day –8 (P <0·05) and on days –8, –7, –6 and –5 combined (P <0·01). Cows in which the concentration of progesterone in plasma did not rise above 4·5 ng/ml during this period did not conceive. After insemination, mean progesterone concentrations between pregnant and non-pregnant cows diverged after day +8. Relatively low concentrations of plasma progesterone (< 1 ng/ml) up to day +8 after insemination did not preclude conception. There was no indication that embryo loss between days +30 and +88 after insemination was related to an insufficiency of ovarian progesterone during early pregnancy.

Reproductive cycle of the common guitarfish, Rhinobatos rhinobatos (Linnaeus, 1758), in Alexandria waters, Mediterranean Sea

1993 ◽  
Vol 44 (3) ◽  
pp. 507 ◽  
Author(s):  
SH Abdel-Aziz ◽  
AN Khalil ◽  
SA Abdel-Maguid
Keyword(s):  
Embryonic Development ◽  
Mediterranean Sea ◽  
Reproductive Cycle ◽  
Egg Size ◽  
Gonadosomatic Index ◽  
Maximum Size ◽  
Reproductive Rate ◽  
Gestation Period ◽  
Monthly Basis ◽  
The Common

The common guitarfish, Rhinobatos rhinobatos, is an ovoviviparous fish having a gestation period of about nine months and a mean reproductive rate of 8 to 14 progeny per pregnancy. Data on gonadosomatic index, maximum ovum diameter, size frequency of ova, and ovarian and uterine contents for 438 specimens (236 females and 202 males), analysed on a monthly basis, indicated a distinct seasonal reproductive cycle for R. rhinobatos. Females reached a maximum size of 181 cm and 20 kg, whereas the maximum size of males was 172 cm and 16 kg. Lengths at which 50% of specimens were mature were 87 and 70 cm for females and males, respectively. Ovarian egg size and male gonadosomatic index both peaked in July and August, indicating that mating occurred in summer. Uterine eggs were present from late February through July, but no embryonic development was evident. Females with full-term embryos were observed in late August, and parturition was followed immediately by ovulation. Ovarian fecundity ranged from 8 to 27 (mean 18) eggs per fish, whereas uterine fecundity ranged from 8 to 14 (mean 12) eggs or embryos per fish.

Seasonal pattern of ovarian growth and interrelated changes in plasma steroid levels, vitellogenesis, and oviductal function in the adult female soft-shelled turtle Lissemys punctata punctata

1996 ◽  
Vol 74 (2) ◽  
pp. 303-311 ◽  
Author(s):  
Supriti Sarkar ◽  
B. R. Maiti ◽  
N. K. Sarkar
Keyword(s):  
Reproductive Cycle ◽  
Plasma Levels ◽  
Seasonal Pattern ◽  
Plasma Progesterone ◽  
Annual Peak ◽  
Ovarian Growth ◽  
Preparatory Phase ◽  
17Β Estradiol ◽  
Winter Hibernation ◽  
Estradiol Concentration

The female reproductive cycle of the freshwater soft-shelled turtle Lissemys punctata punctata was studied by correlating ovarian growth with changes in plasma levels of steroids (17β-estradiol and progesterone), vitellogenic indices (calcium, lipid, protein, and cholesterol), and oviductal changes (growth, glycogen, and peroxidase levels). Ovarian growth starts after winter hibernation, proceeds slowly during the preparatory phase (March–June), becomes rapid in the recrudescent phase (July), and peaks in the breeding phase (August–September). Subsequently, the follicles undergo atresia in the regressive phase (October–November), which is followed by the quiescent phase (December–February) marked by negligible ovarian growth. Plasma levels of 17β-estradiol and vitellogenic indices reflect the same pattern of change as ovarian growth. The plasma progesterone concentration remains low throughout the reproductive cycle, except that the titre reaches a postovulatory peak and then declines prior to oviposition. Oviductal mass and glycogen and peroxidase concentrations correspond to changes in plasma estradiol concentration. The findings indicate that the seasonal reproductive cycle of L. p. punctata is characterized by a single annual peak of ovarian growth and estrogen secretion compared with a double peak recorded in other single-clutch turtles.

scholarly journals Perinatal Changes in Plasma Oestradiol-17b, Cortisol and Progesterone and the Initiation of Lactation in Sows

1983 ◽  
Vol 36 (2) ◽  
pp. 173 ◽  
Author(s):  
David L Willcox ◽  
Peter G Arthur ◽  
Peter E Hartmann ◽  
Justin L Whitely
Keyword(s):  
Plasma Cortisol ◽  
Post Partum ◽  
Plasma Concentrations ◽  
Milk Composition ◽  
Plasma Cortisol Level ◽  
Point Scale ◽  
Mature Milk ◽  
Plasma Progesterone ◽  
Peripheral Plasma ◽  
Plasma Oestradiol

The concentrations in peripheral plasma of oestradiol-17 p, cortisol and progesterone were determined in 10 sows from 5-6 days prepartum to 4 days post partum. At the same time, the presence and composition of mammary secretion was monitored. Plasma progesterone levels declined from 4�9�0�6flgl-1 (mean�s.e.m.) 12h prepartum to 2�6�0�5flgl-1 at farrowing, and to about 1 flg 1- I by day 1 post partum, although the timing of the fall in plasma progesterone level ranged from day 4 prepartum to the day of parturition in individual sows. Farrowing in all sows was associated with a fall in plasma oestradiol-17P levels, from 0'68�0'07 flgl-' to O'13flgl-' 12h after the start of labour, and with a rise in plasma cortisol level from 14'09�3'74flgl-1 24h prepartum to 43� 66 � 7� 06 flg 1- I when lactation was becoming established. Mammary secretion was obtained from individual sows up to 3 days prepartum: the onset of lactation was assessed visually by evaluation of the colour and viscosity of secretions against a six-point scale ranging from no secretion to precolostral secretion to mature milk. Lactogenesis was estimated also from the concentrations of lactose, immunoglobulins G, Na + and K + in mammary secretions obtained postnatally. The timing of the first expression from the teats was not correlated with the onset of lactation as measured by changes in milk composition. Further more, there was no relationship between circulating progesterone, oestradiol-17 p or cortisol levels and the day on which secretion was first expressed. We conclude that, in the sow, lactogenesis, as indicated by changes in milk composition, coincides postnatally with decreased plasma concentrations of oestradiol-17 p, cortisol and progesterone. Furthermore, observation of the colour and viscosity of mammary secretion, rather than analysis of its constituents, may determine lactogenesis inaccurately in sows owing to the rapid but variable onset of lactation in this species.

CONCENTRATIONS OF OESTRADIOL-17β, OESTRONE AND PROGESTERONE IN JUGULAR VENOUS PLASMA OF COWS DURING THE OESTROUS CYCLE AND IN EARLY PREGNANCY

1973 ◽  
Vol 73 (2) ◽  
pp. 374-384 ◽  
Author(s):  
R. G. Glencross ◽  
I. B. Munro ◽  
B. E. Senior ◽  
G. S. Pope
Keyword(s):  
Early Pregnancy ◽  
High Plasma ◽  
Oestrous Cycle ◽  
Progesterone Level ◽  
Plasma Progesterone ◽  
Plasma Oestradiol ◽  
Second Peak ◽  
Venous Plasma

ABSTRACT Plasma oestradiol-17β concentrations rise slowly in the late progestational phase of the bovine oestrous cycle before plasma progesterone levels fall and then rise rapidly to a pre-oestrous peak of about 6 pg/ml as progesterone levels fall rapidly. The oestradiol-17β level (on average) falls during oestrus and both steroids show minimum levels 1–2 days after oestrus. Both then rise again, oestradiol-17β to a second peak 6–7 days after the pre-oestrous peak as progesterone level continues to rise. In a cow in the first 30 days of pregnancy, when plasma progesterone levels remained generally high after the 15th day, the pattern of plasma oestradiol-17β levels was very similar to that expected had it not conceived. Thus in the cycle and the first 30 days of pregnancy the main oestradiol-17β peaks are found at about 21 day intervals, each being followed by a smaller peak 6–7 days later. Either oestradiol-17β peak may assume a pre-oestrous and pre-ovulatory role in the absence of high plasma progesterone levels.

Increase in plasma progesterone caused by undernutrition during early pregnancy in the ewe

Reproduction ◽  
1971 ◽  
Vol 24 (1) ◽  
pp. 146-a-147 ◽  
Author(s):  
I. Cumming ◽  
B. Mole ◽  
J Obst ◽  
M. Blockey ◽  
C. Winfield ◽  
...  
Keyword(s):  
Early Pregnancy ◽  
Plasma Progesterone

scholarly journals Assessment of ergot (Claviceps purpurea) exposure in pregnant and postpartum beef cows

2018 ◽  
Vol 98 (4) ◽  
pp. 688-700 ◽  
Author(s):  
T. Grusie ◽  
V. Cowan ◽  
J. Singh ◽  
J. McKinnon ◽  
B. Blakley
Keyword(s):  
Ergot Alkaloid ◽  
Post Partum ◽  
Ergot Alkaloids ◽  
Maximum Size ◽  
Beef Cows ◽  
Plasma Prolactin ◽  
Claviceps Purpurea ◽  
Ambient Temperatures ◽  
Beef Cow ◽  
The Impact

Cows were fed ration for 9 wk containing 5, 48, 201, and 822 μg kg−1 ergot alkaloids. The objective was to evaluate the impact of ergot consumption in beef cow–calf operations. Ergot alkaloids up to 822 μg kg−1 did not alter the weight of peripartum and postpartum beef cows (P = 0.93) or nursing calves (P = 0.08), rectal temperature (P = 0.16), or plasma prolactin concentrations (P = 0.30) at moderate ambient temperatures. Ergot did not influence the time (>1 ng mL−1; P = 0.79) or the progesterone concentration (P = 0.38) at the time of first postpartum rise or the size of the first (14 ± 0.6 mm; P = 0.40) and second (13 ± 0.5 mm; P = 0.41) follicles to ovulate. The maximum size of the first postpartum corpus luteum (CL) was 4 mm larger in the 822 μg kg−1 ergot group compared with the control (P = 0.03) for the first ovulation post partum, but not for the second (P = 0.11). There was no effect of ergot exposure on the number of days until the appearance of the first (43 ± 4 d; P = 0.95) or second (52 ± 4 d; P = 0.98) CL post partum. Ergot alkaloid concentrations up to 822 μg kg−1 did not affect pregnancy rates (X2 = 0.36). In conclusion, ergot alkaloid exposure for 9 wk to concentrations as high as 822 μg kg−1 did not alter performance in pregnant and postpartum beef cattle at moderate ambient temperatures.

PERIPHERAL CONCENTRATIONS OF PROGESTERONE, CORTISOL, ALDOSTERONE, SODIUM AND POTASSIUM IN THE PLASMA OF THE TADMIT EWE DURING PREGNANCY AND PARTURITION

1980 ◽  
Vol 84 (1) ◽  
pp. 25-33 ◽  
Author(s):  
LOUISA BOULFEKHAR ◽  
ROGER BRUDIEUX
Keyword(s):  
Early Pregnancy ◽  
Competitive Inhibition ◽  
Plasma Aldosterone ◽  
Renin Substrate ◽  
Sodium Potassium ◽  
Blood Concentrations ◽  
Plasma Progesterone ◽  
Mean Values ◽  
The Mean ◽  
Sodium And Potassium

The peripheral blood concentrations of progesterone, cortisol, aldosterone and electrolytes were measured simultaneously in 16 multiparous ewes of the Tadmit Algerian breed during pregnancy and parturition. Plasma progesterone concentrations were similar to those of the luteal phase of the oestrous cycle during the first third of gestation. Between 60 and 135 days after mating, the levels of plasma progesterone increased steadily to values eight times those found in early pregnancy. However, no change was observed from days 43 to 28 before parturition. Mean progesterone concentrations declined during the 17 days preceding lambing, decreasing more quickly during the last 3 days. Pregnancy did not increase the levels of plasma cortisol and the mean values during pregnancy did not exceed 0·5 μg/100 ml until 90 days after mating. It then tended to decrease between days 57 and 17 before parturition, before rising slightly on both day 7 and on the day of lambing. Concentrations of plasma aldosterone were low during early pregnancy (about 2 ng/100 ml). Thereafter, as with progesterone, they rose from days 58 to 43, did not change from days 43 to 28 and increased again until maximum levels were reached 17 days prepartum and then levels decreased sharply until 7 days before lambing. At this stage, progesterone levels continued to decrease during the last 7 days while aldosterone concentrations once more increased. Sodium and potassium concentrations changed little during pregnancy, although the sodium: potassium ratio tended to increase during the last 17 days of pregnancy. It is suggested that changes in the levels of plasma aldosterone during gestation in the ewe are the result of the competitive inhibition of aldosterone by progesterone at a renal level and that the rise of aldosterone during the last few days of pregnancy is largely due to the stimulation of renin substrate production by oestrogens whose values are high at this period.

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