Progesterone levels in peripheral plasma of Rocky Mountain bighorn ewes (Ovis canadensis) during the estrous cycle and pregnancy

1980 ◽  
Vol 58 (6) ◽  
pp. 1105-1108
Author(s):  
P. E. Whitehead ◽  
E. H. McEwan
Keyword(s):  
Estrous Cycle ◽  
Rocky Mountain ◽  
Ovis Canadensis ◽  
Rapid Decline ◽  
Plasma Progesterone ◽  
Peripheral Plasma

Plasma progesterone levels of three Rocky Mountain bighorn ewes (Ovis canadensis) were determined during anestrus, estrus, and pregnancy. Eighteen-month-old ewes had "silent" heats with peak progesterone levels ranging from 1.0 to 2.2 ng/mL. At [Formula: see text] years of age, luteal activity preceded behavioural estrus and successful breeding. During the first 50 days of gestation, plasma progesterone levels increased to 8.5 ng/mL (8.0–9.2 ng/mL). From 50 to 80 days, progesterone levels decreased, followed by an increase to peak values of 13.3 to 23.2 ng/mL. A rapid decline in progesterone levels occurred about the time of parturition.

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.

Peripheral Plasma Progesterone Levels During the Ovine Estrous Cycle

Endocrinology ◽  
1969 ◽  
Vol 85 (1) ◽  
pp. 11-15 ◽  
Author(s):  
G. H. STABENFELDT ◽  
J. A. HOLT ◽  
L. L. EWING
Keyword(s):  
Estrous Cycle ◽  
Plasma Progesterone ◽  
Peripheral Plasma

SEQUENTIAL CHANGES IN PLASMA PROGESTERONE LEVELS IN THE EWE DURING THE ESTROUS CYCLE, AND DURING PREGNANCY IN INTACT AND OVARIECTOMIZED SHEEP

1973 ◽  
Vol 53 (1) ◽  
pp. 25-34 ◽  
Author(s):  
I. R. SARDA ◽  
H. A. ROBERTSON ◽  
T. C. SMEATON
Keyword(s):  
Estrous Cycle ◽  
Population Sample ◽  
Maximum Level ◽  
Individual Variability ◽  
Progesterone Concentration ◽  
Sharp Rise ◽  
Plasma Progesterone ◽  
Peripheral Plasma ◽  
The Individual ◽  
Second Peak

The progesterone concentration in the peripheral plasma was measured sequentially in individual ewes during the estrous cycle, and during gestation and parturition in intact and in ovariectomized ewes. Progesterone levels during anestrum and in ovariectomized ewes have been measured. During the estrous cycle the concentration was lowest (0.1–0.2 ng/ml) from 36 h before to 48 h after, the onset of estrus. A similar concentration was found during anestrum and in ovariectomized ewes, suggesting that at estrus the progesterone comes from nonovarian tissue, probably the adrenal gland. On the 4th day of the cycle (day of estrus = 1st day) the progesterone level began to rise reaching a peak of 1.9–4.0 ng/ml on the 10th day. After a decline, the level rose to a second peak on the 14th or 15th day. Three to 4 days before the next onset of estrus the concentration dropped sharply over a period of 48 h to a low basal level (0.1–0.2 ng/ml). During early pregnancy the plasma progesterone concentration remained fairly constant at a level similar to the maximum level found during the cycle. A sharp rise started around the 80th day, reaching 15–20 ng/ml around the 110th day. This was followed by a second peak, then a decline in the plasma progesterone concentration before parturition, but the time at which this began was variable (1–11 days) and even on the day of parturition the level was generally > 3 ng/ml. A basal level of < 0.5 ng/ml was reached within 24 h after parturition. Pregnancy in ewes ovariectomized soon after conceiving was maintained with implants of progesterone. When these implants were removed around the 90th day of pregnancy the plasma progesterone concentration showed a similar rise to that which occurred in intact pregnant ewes at this time. Parturition occurred normally in these ewes. Within the limited population sample, any relation between the plasma progesterone and the number, sex, or weight of the fetus (es) was masked by the individual variability in the concentration of progesterone.

PROPRANOLOL-BLOCKADE OF VASOPRESSIN INDUCED INCREASE IN PLASMA PROGESTERONE IN EARLY HUMAN PREGNANCY

1971 ◽  
Vol 66 (2) ◽  
pp. 283-288 ◽  
Author(s):  
Petter Fylling
Keyword(s):  
Cyclic Amp ◽  
Uterine Cervix ◽  
Adenosine Monophosphate ◽  
First Trimester ◽  
Blocking Agent ◽  
Simultaneous Administration ◽  
Plasma Progesterone ◽  
Human Pregnancy ◽  
Peripheral Plasma ◽  
Early Human

ABSTRACT Following continuous dilation of the uterine cervix or intravenous infusion of vasopressin during the first trimester of human pregnancy, a marked increase in the peripheral plasma progesterone levels was observed. This effect was blocked by simultaneous administration of propranolol (Inderal®), a β-blocking agent. It is suggested that both these stimulating and inhibiting effects might be related to 3′, 5′-adenosine monophosphate (cyclic AMP). The results indicate the existence of β-receptors in steroid producing tissues.

scholarly journals Brucellosis in Captive Rocky Mountain Bighorn Sheep (Ovis canadensis) Caused by Brucella abortus Biovar 4

2004 ◽  
Vol 40 (2) ◽  
pp. 311-315 ◽  
Author(s):  
Terry J. Kreeger ◽  
Walter E. Cook ◽  
William H. Edwards ◽  
Todd Cornish
Keyword(s):  
Brucella Abortus ◽  
Rocky Mountain ◽  
Bighorn Sheep ◽  
Ovis Canadensis

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.

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