Mean Corpus Luteum Research Articles

CORRELATION BETWEEN CORPUS LUTEUM VOLUME USING 2D ULTRASOUND AND COLOR-DOPPLER STUDY OF CORPUS LUTEUM VASCULATURE WITH MATERNAL SERUM CA-125 LEVEL IN PROGNOSIS OF FIRST TRIMESTER THREATENED ABORTION

Background: Threatened miscarriage is a common complication in the first trimester of pregnancy and is often associated with anxiety regarding pregnancy outcome. Approximately, 20% of pregnant women have symptoms of threatened abortion in the first trimester of pregnancy. A single serum cancer antigen 125 (CA-125) level determination is valuable in women with imminent abortion presenting with abdominal pain, vaginal bleeding or both rather than serial measurements. Objective: To evaluate the prognostic value of correlating the corpus luteum volume measured by two-dimensional ultrasound, and color doppler blood flow changes in the corpus luteum together with the results of serum CA-125 at the time of initial presentation with pregnancy outcome in patients with first trimesteric threatened abortion. Patients and methods: This prospective controlled study was held during the period from May 2015 to May 2018 on 100 women on their first trimester of pregnancy, 50 women having normal uncomplicated pregnancy and 50 women with clinical diagnosis of threatened abortion. The latter group was further subdivided into: group of patients who aborted (14 patients), and another group who continued their pregnancy and proceeded into the second trimester (36 patients). Results: It was found that the mean corpus luteum peak systolic velocity (CL PSV) for the threatened abortion (aborted) group was 30.68 ± 18.9 cm/sec, while for the threatened abortion (continued) group was 22.03 ± 12.9 cm/sec, and for the control group was 21.58 ± 13.77 cm/sec. The difference was statistically significant between threatened abortion (aborted) group and each of the threatened abortion (continued) group and the control group. The difference was statistically non-significant between the threatened abortion (continued) group, and the control group. The cut-off value of CL PSV at which there was a high probability of termination of pregnancy in threatened abortion cases, reached 17.785 cm/sec with a sensitivity of 63.6% and specificity of 54.4%. Conclusion: Serum CA-125 level determination was valuable in the women with symptoms of threatened abortion with a cut-off limit of 31.85 IU/ml of CA-125 level which carried a sensitivity of 86.4% and specificity of 80.7%. The study suggested that CA- 125 may be a cheap, sensitive and specific method in prediction of the cases of threatened abortion.

Circulating progesterone concentrations and preovulatory follicle diameters affecting ovulatory response in crossbred dairy heifers, following a 7-day progesterone-based synchronization protocol.

The present study was aimed at evaluating the differences of ovarian follicular dynamics and circulating progesterone (P4) concentrations between crossbred Holstein heifers that ovulated and did not ovulate after a P4-based synchronization protocol. Twenty-one crossbred (Holstein × Thai native) heifers with random stages of the oestrous cycle were subjected to the ovulation synchronization protocol, using an intravaginal P4-releasing device (Eazi-Breed CIDR®) for 7 days. Out of 21 CIDR-treated heifers, 14 ovulating heifers were classified as the ovulatory group and 7 non-ovulating heifers were considered the anovulatory group. The heifers having new wave emergence in ovulatory and anovulatory groups were 11/14 (78.6%) and 4/7 (57.1%), respectively. In ovulating heifers, the mean (± SEM) diameter of preovulatory follicle (PF, mm) was significantly larger, compared to non-ovulating heifers (7.21 ± 0.32 versus 4.04 ± 0.44; P = 0.001), while the mean (± SEM) follicular growth rates (mm/d) in non-ovulating heifers tended to be lower, compared to ovulating heifers (0.73 ± 0.17 versus 1.06 ± 0.08; P = 0.07). The mean (± SEM) circulating P4 concentration (ng/ml) throughout the CIDR protocol (0-10 days) in non-ovulating heifers was significantly higher, in comparison with ovulating heifers (2.82 ± 0.27 versus 1.83 ± 0.16; P = 0.02). However, no significant difference in the mean corpus luteum volume between groups was observed. In conclusion, the present results suggested that elevated circulating P4 concentrations and smaller PF diameters could cause ovulation failure in crossbred Holstein heifers, following a 7-day CIDR-based synchronization protocol.

Estradiol-17β Injection Induces Ovulation in Llamas

This study aimed to investigate the effect of three different doses of estradiol-17β on ovulation and subsequent luteal development and function in llamas. Twenty-three llamas were examined daily by transrectal ultrasonography until the detection of an ovulatory follicle (≥8 mm). Thereafter, animals were divided into five groups: Control (n = 3; treated with 1.6 ml of saline solution), GnRH group (n = 6, treated with an intravenous injection of 8.4 μg Buserelin), and estradiol groups that received 0.6 mg (E1, n = 4), 1 mg (E2, n = 4), or 1.6 mg (E3, n = 6) of estradiol-17β intravenously. Detection of ovulation was based on ultrasonographic visualization of disappearance of the largest follicle and subsequent presence of a newly formed corpus luteum (CL) and progesterone concentration exceeding 1 ng ml−1. Daily blood samples were collected to determine plasma progesterone concentration. Ovulation rate was 0% for control and E1 groups, 25% for E2 group, and 100% for GnRH and E3 groups. Differences in the mean CL diameter between GnRH and E3 groups were not statistically significant. Plasma progesterone concentration was similar between groups during the different days in ovulated animals. However, the day that the plasma progesterone concentration was above 1 ng ml−1 and the day that the highest plasma progesterone concentration was achieved differed among E3 and GnRH groups, occurring later in females treated with estradiol. In conclusion, an injection of estradiol-17β is capable of inducing ovulation in llamas and the response depends on the dose used. Most of the animals required the highest tested dose (1.6 mg) to induce the ovulatory process. Although the CL diameter in females induced to ovulate with estradiol was similar to that in llamas induced to ovulate with a GnRH analog, the rise in plasma progesterone concentration above 1 ng ml−1 and the peak progesterone concentration were attained 1 day later in the estradiol treated females.

Anti-Mullerian Hormone and Follicle Counts as Predictors of Superovulatory Response and Embryo Production in Beef Cattle

This study evaluated Anti-Mullerian hormone (AMH) and/or follicle counts as predictors of subsequent superovulatory response and embryo production in 79 beef cows. Before superovulation, 3 to 5 mm follicles presented on the ovaries of donor cows were counted, and blood was collected for measure of serum AMH. Across cows, serum AMH ranged from 0.013 to 0.898 ng/mL, with a mean of 0.293 ng/mL. The distribution of both AMH concentrations and follicle counts were divided into quartiles (AMH Q1 through Q4, with Q1 the lowest and Q4 the highest) for analysis. Donor cows in AMH Q4 had a greater (P < 0.001) number of 3 to 5 mm follicles at the start of superovulation than did donors in either Q1 or Q2. At embryo collection, cows in AMH Q3 and 4 had more (P < 0.001) palpable corpora lutea (CL) than cows in AMH Q1. The mean number of embryos recovered from donor cows in AMH Q4 was greater (P < 0.001) than those recovered from cows in either AMH Q1 or 2, but similar to that of AMH Q3. Analysis indicated that AMH was positively correlated (P < 0.001) with mean follicles (r = 0.458), CL (r = 0.452) and embryos recovered (r = 0.430). Donor cows with higher follicle counts (F Q3 and 4) at the start of superovulation had more (P < 0.001) palpable CL at embryo collection than donor cows in F Q1 or 2. More (P < 0.001) embryos were recovered from cows with the highest follicle counts (F Q4) as compared with cows having lower (F Q1 and 2) follicle counts. Results confirm that relative AMH concentration was positively correlated with number of small antral follicles in the ovaries of cows; both AMH measure and antral follicle counts might be used to predict subsequent superovulatory response in beef cows.

Evaluating blood perfusion of the corpus luteum in beef cows during fescue toxicosis.

The aim of this study was to determine if fescue toxicosis altered blood perfusion in the corpus luteum (CL) and peripheral concentrations of progesterone in cattle. The estrous cycles of 36 nonpregnant Angus or Charolais cows were synchronized in 2 replicates using the CO-Synch+CIDR protocol. Seven days after initiation of the protocol, cows were assigned (d 0) to 1 of 2 dietary treatments: 2.5 kg of 1) Kentucky-31 endophyte-infected (KY31; = 14) or 2) MaxQ novel endophyte (MaxQ; = 12) tall fescue seed. On d 7, ovaries were examined using ultrasonography, and only cows that had 1 CL present remained on the study ( = 26). Images of blood perfusion of CL, blood samples, rectal temperatures, and blood pressure of tails were collected on d 10, 13, 15, and 18. Images of CL blood perfusion were analyzed using ImageJ software for pixel density, and scored visually (0 to 9 with 0 = no perfusion, 9 = complete perfusion) by 2 independent technicians. The MIXED procedure of SAS was used with day as a repeated measure. Least squares means and SEM are reported. Cows receiving KY31 had greater rectal temperatures ( 0.003; 38.76 ± 0.08°C) than those receiving MaxQ (38.44 ± 0.08°C), providing evidence that the cows treated with KY31 were influenced by fescue toxicosis. Pulse pressure and mean arterial pressure were decreased ( < 0.01) in cows receiving KY31 (55.26 ± 2.81 and 80.06 ± 2.72 mmHg, respectively) than MaxQ (66.58 ± 3.03 and 91.38 ± 2.93 mmHg, respectively). Concentrations of progesterone were similar ( = 0.54) between cows receiving KY31 (6.04 ± 0.53 ng/mL) or MaxQ (6.36 ± 0.63 ng/mL). Pixel densities ( = 0.14) and visual perfusion scores were similar ( = 0.11) between cows receiving KY31 (1477.20 ± 655.62 pixels and 2.23 ± 0.34, respectively) or MaxQ (2934.70 ± 718.20 pixels and 3.00 ± 0.36, respectively). Mean CL volume was similar ( 0.95) between treatments. In conclusion, blood perfusion of CL or peripheral concentrations of progesterone were not altered at the onset of fescue toxicosis in this short-term study, indicating that a decrease in blood perfusion of the CL may not be a primary mechanism involved in decreased reproductive efficiency of cattle during fescue toxicosis.

233 ANTI-MÜLLERIAN HORMONE AS A PREDICTIVE ENDOCRINE MARKER FOR SUPEROVULATORY RESPONSE AND EMBRYO PRODUCTION IN BEEF CATTLE

A study investigated the use of anti-Müllerian hormone (AMH) and/or follicle counts as a predictor of subsequent superovulatory response and embryo production in 79 beef cows. Before initiation of superovulation, ultrasonography was used to scan the ovaries of each donor cow to record the number of 3 to 5 mm follicles present, and a blood sample was collected for measure of serum AMH. At the time of embryo collection, the ovaries of donor cows were palpated to estimate the number of corpora lutea (CL) present on each ovary. Recovered embryos were evaluated for stage of development and morphological quality. Across cows, serum AMH ranged from 0.013 to 0.898 ng mL–1, with a mean of 0.293 ng mL–1. The distribution of AMH concentrations was divided into quartiles (AMH Q1 through Q4, with Q1 the lowest and Q4 the highest, ng mL–1) for analysis (ANOVA). Number of donors/collections in AMH Q1 through Q4 was 26, 22, 24, and 24, respectively. Donor cows in AMH Q4 had a greater (P &lt; 0.001) number of 3- to 5-mm follicles at the start of superovulation than did donors in either Q1 or Q2. At embryo collection, cows in AMH Q3 and 4 had more (P &lt; 0.001) palpable CL than cows in AMH Q1. The mean number of embryos recovered from donor cows in AMH Q4 (20.1 ± 1.8) was greater (P &lt; 0.001) than those recovered from cows in either AMH Q1 (9.8 ± 1.8) or 2 (9.4 ± 1.9), but similar to that of AMH Q3 (15.5 ± 1.8). Percentages of recovered embryos classified as transferrable, degenerate, or unfertilized were similar (P ≥ 0.275) across AMH quartiles. Analysis indicated that AMH was positively correlated (P &lt; 0.001) with mean follicles (r = 0.458), CL (r = 0.452), and embryos recovered (r = 0.430). To determine if follicle counts at the start of superovulation are predictive of superovulatory response, the distribution of follicle counts was divided into quartiles (F Q1 through Q4, with Q1 the lowest and Q4 the highest) for analysis. Donor cows with higher follicle counts (F Q3 and 4) at the start of superovulation had more (P &lt; 0.001) palpable CL at embryo collection than donor cows in F Q1 or 2. More (P &lt; 0.001) embryos (20.0 ± 2.2 v. 9.6 ± 1.8 and 11.6 ± 1.6) were recovered from cows with the highest follicle counts (F Q4) compared with cows having lower (F Q1 and 2) follicle counts, respectively. The percentage of transferable embryos and unfertilized ova were similar (P ≥ 0.688) across follicle count quartiles. As was noted for AMH, mean number of follicles at the start of superovulation was positively correlated (P &lt; 0.001) with mean CL (r = 0.556) and mean embryos (r = 0.423) but not percentages of viable or degenerate embryos or unfertilized oocytes (P ≥ 0.153). Results confirm that relative AMH concentration was positively correlated with number of small antral follicles in the ovaries of cows and might be used to either predict superovulatory response or possibly adjust superovulatory regimen to improve superovulatory response. Further study is needed to determine the effectiveness of using either AMH concentration or follicle counts to adjust superovulatory regimens.

348 ANTI-MÜLLERIAN HORMONE AND SUPEROVULATORY RESPONSE IN DONOR COWS MANAGED IN 2 SEMIARID ENVIRONMENTS IN NORTHWEST MEXICO

An embryo transfer program in cows relies on the superovulatory (SPO) response after receiving a hormonal treatment. Anti-Müllerian hormone (AMH) has been proposed as an endocrine marker associated to superovulation; however, the SPO response of donors has also been influenced by the environment. Thus, objective herein was to evaluate effects of serum AMH levels on number of ovarian follicles (NOF), corpora lutea (CL), and transferable embryos (TE) in superovulated donor cows managed under summer or winter conditions in northwest Mexico. Fifty-two cows in a random stage of the oestrous cycle were used in this study. All cows received an Eazi-Breed CIDR cattle insert (1.384 g of progesterone; Zoetis, USA), and 2.76 mg of oestradiol benzoate (Sigma-Aldrich, St. Louis, MO, USA) plus 50 mg of progesterone (Vetoquinol, Canada) given i.m. to synchronize follicular wave emergence (Day 0). The SPO treatment started on Day 4 with decreasing doses (120, 80, 40, and 20 mg) of Folltropin-V (Vetoquinol, Canada) injected twice daily until Day 7. Artificial insemination was performed on days 8 p.m. and 9 a.m. and ova/embryos were collected on Day 15. Transrectal ultrasonography was done on Days 8 and 15 to determine the number of follicles &gt;9 mm in diameter on Day 8 and CL on Day 15, respectively. Blood samples were collected on the first day of SPO treatment (Day 4) to measure serum AMH concentrations, which served to classify cows as high- (&gt;400; n = 29) and normal-AMH donors (100–400 pg mL–1; n = 23). A mixed effects model was used to analyse SPO response in cattle including level of AMH and season as fixed effects, age as covariate, and sire as random. Level of AMH, season, and their interaction resulted as significant (P &lt; 0.05) sources of variation. Pearson correlations were determined between serum AMH concentrations and SPO response for summer and winter. Average serum levels of AMH were 471.5 ± 70.4 and 1194.2 ± 57.3 pg mL–1 during summer and winter, respectively. The SPO response differed in high- and normal-AMH donor cows (P &lt; 0.05). Mean (± s.e.m.) NOF, CL, and TE were 19.8 ± 1.0, 12.8 ± 0.6, and 7.3 ± 0.5 for high-AMH donors, and 10.9 ± 1.6, 6.5 ± 1.9, and 3.8 ± 1.1 for normal-AMH donor cows, respectively. Environment of donor cows also influenced SPO response as NOF, CL, and TE increased 42, 50, and 45%, respectively, during winter compared with summer (P &lt; 0.05). Correlations among NOF, CL, and TE with serum AMH levels were moderate for donor cows managed during winter (0.657, 0.523, and 0.431, respectively; P &lt; 0.01), and low in cows managed during summer (0.309, 0.195, and 0.085, respectively; P &gt; 0.05). Results from this study indicated that SPO response in donor cows is associated with serum concentrations of AMH; however, the relationship among these variables appears to be affected in the summer when drought and severe heat stress are common. We concluded that under winter conditions of northwest Mexico, the serum levels of AMH should be considered as an endocrine marker associated with ovarian traits indicative of the SPO response in donor cows.

Effects of varying doses of β-nerve growth factor on the timing of ovulation, plasma progesterone concentration and corpus luteum size in female alpacas (Vicugna pacos).

Ovulation in camelids is induced by the seminal plasma protein ovulation-inducing factor (OIF), recently identified as β-nerve growth factor (β-NGF). The present study measured the total protein concentration in alpaca seminal plasma using a bicinchoninic acid (BCA) protein quantification assay and found it to be 22.2±2.0mgmL(-1). To measure the effects of varying doses of β-NGF on the incidence and timing of ovulation, corpus luteum (CL) size and plasma progesterone concentration, 24 female alpacas were synchronised and treated with either: (1) 1mL 0.9% saline (n=5); (2) 4µg buserelin (n=5); (3) 1mg β-NGF protein (n=5); (4) 0.1mg β-NGF (n=5); or (5) 0.01mg β-NGF (n=4). Females were examined by transrectal ultrasonography at 1-2-h intervals between 20 and 45h after treatment or until ovulation occurred, as well as on Day 8 to observe the size of the CL, at which time blood was collected to measure plasma progesterone concentrations. Ovulation was detected in 0/5, 5/5, 5/5, 3/5 and 0/4 female alpacas treated with saline, buserelin, 1, 0.1 and 0.01mg β-NGF, respectively. Mean ovulation interval (P=0.76), CL diameter (P=0.96) and plasma progesterone concentration (P=0.96) did not differ between treatments. Mean ovulation interval overall was 26.2±1.0h. In conclusion, buserelin and 1mg β-NGF are equally effective at inducing ovulation in female alpacas, but at doses ≤0.1mg, β-NGF is not a reliable method for the induction of ovulation.

Diffraction-enhanced Synchrotron Imaging of Bovine Ovaries Ex Vivo

ObjectivesThe objective of this study was to test the hypothesis that diffraction-enhanced imaging (DEI), a synchrotron x-ray imaging technique, would provide greater contrast for evaluating bovine ovaries compared with conventional diagnostic ultrasonography. Materials and MethodsBovine ovaries were evaluated ex vivo as follows: fresh without radiographic arterial contrast (n = 2), fresh with contrast (n = 1), preserved in 10% formalin without contrast (n = 2), and preserved with contrast (n = 1). Each ovary was imaged with DEI and subsequently with ultrasonography and histology. The ability to visualize and differentiate preantral and antral follicles, corpora lutea (CL), and cumulus oocyte complexes (COCs) were compared using DEI, ultrasonography, and histology. The diameter of follicles and CL were measured and compared using ultrasonography, DEI, and histology. The diameter of the smallest follicle detected was reported using each of the three imaging methods. The number of antral follicles (antral follicle count ≥2 mm) was compared between ultrasonography and DEI. ResultsDEI enabled the detection of 71% of follicles and 67% of CL that were detected ultrasonographically. However, DEI did not allow the detection of COCs and cell layers of the follicle wall that were visualized histologically. Luteal tissues were not easily distinguished using DEI, and DEI was inferior for differentiating follicles and CL compared with ultrasonography. The mean follicle diameter was similar between DEI (4.00 ± 0.35 mm, fresh with contrast; 9.62 ± 2.43 mm, fresh without contrast) and ultrasonography (3.85 ± 0.28 mm, fresh with contrast; 8.97 ± 2.60 mm, fresh without contrast) (P > .05). However, the mean follicle diameter was greater using both DEI (4.00 ± 0.35 mm) and ultrasonography (3.85 ± 0.28 mm) compared with histology (2.21 ± 0.38 mm; P = .01, fresh ovaries with contrast). The mean CL diameter was similar between DEI (11.64 ± 1.67 mm), ultrasonography (9.34 ± 0.35 mm), and histology (9.59 ± 0.36 mm) (P > .05). The mean diameter of the smallest follicle detected was similar between DEI (3.06 ± 0.45 mm) and ultrasonography (2.95 ± 0.74 mm); both DEI and ultrasonographic measurements were greater than histology (0.39 ± 0.04 mm, P < .0001). The mean antral follicle count was similar between ultrasonography (6.50 ± 0.71 mm, fresh with no contrast; 6.50 ± 2.50 mm, preserved with no contrast) and DEI (4.50 ± 0.50 mm, fresh with no contrast; 6.50 ± 0.50 mm, preserved with no contrast) (P > .05). ConclusionsThe contrast resolution of antral follicles, CL, and COCs in bovine ovaries was inferior using DEI compared with ultrasonography and histology. Alternative synchrotron techniques, such as phase-contrast computed tomography and DEI computed tomography, may prove more effective than DEI for imaging ovaries ex vivo.

Effects of ethanolic fruit extract of Picralima nitida (Stapf) on fertility of pregnant rats

The ethanolic fruit extract of Picralima nitida (Stapf) which proved to be a potent spasmogen in vitro was tested in pregnant female Sprague Dawley rats. Fifteen successfully mated female rats were divided into three groups of five animals each. Groups 1 and 2 received intraperitoneal injection of 50 and 500 mg/kg body weight of the extract dissolved in distilled water, respectively, on days 15 and 16 of gestation. Rats in group 3 were given equivalent volumes of distilled water and served as negative control. On the 20th day of gestation, the following parameters: percentage of pregnant females per group (PPF), mean live foetal number (LFN), mean corpus luteum number (CLN), mean resorbed embryo number per pregnant female (REN) and mean day 20 foetal crown-rump lengths (FCRL), were evaluated and fertility index calculated. The extract at 50 mg/kg body weight did not cause any obvious abortion in the treated animals. However, the extract at 50 mg/kg body weight, when compared to the control, significantly (p < 0.05) reduced the mean FCRL and the fertility index, respectively. On the other hand, the extract at 500 mg/kg body weight caused mortality in all the treated pregnant animals. The histopathology revealed necrosis of the kidney cells. From the study, it was concluded that this extract did not cause any obvious abortion, rather it caused mortality in all the treated pregnant rats.

3 APPLICATION OF LAPAROSCOPIC OVIDUCTAL ARTIFICIAL INSEMINATION FOR CONSERVATION MANAGEMENT OF BRAZILIAN OCELOTS AND AMUR TIGERS

The Brazilian ocelot (Leopardus pardalis mitis) and Amur tiger (Panthera tigris altaica) are 2 iconic cat species that are becoming increasingly imperiled in the wild. Although both felids are managed in North American zoos by species survival plans (SSP), their long-term sustainability has proven difficult through captive breeding alone, necessitating the development and application of assisted reproductive techniques. Our recent progress using laparoscopic oviducal artificial insemination (LO-AI) in domestic cats (Conforti et al. 2013 Biol. Reprod. 89, 1–9) suggested that this approach could help improve reproductive management of nondomestic felids. In this study, our objectives were to (1) assess ovarian and endocrine responses to 2 exogenous gonadotropin regimens in ocelots and Amur tigers, and (2) investigate fertility and offspring production following LO-AI with freshly collected and/or frozen–thawed semen in both felid species. Female ocelots (n = 13) and Amur tigers (n = 10), housed at 16 North American zoos and recommended for breeding by the Ocelot and Tiger SSP, were treated with 2 different eCG/porcine LH (pLH) regimens (400 or 600 IU of eCG, 3000 IU of pLH, ocelots; 750 or 1000 IU of eCG, 10 000 IU of pLH, tigers). Ovarian responses were evaluated laparoscopically at 39 to 45 h post-pLH, and ovulatory females were inseminated using low numbers of freshly collected or frozen–thawed spermatozoa (≤5 million motile sperm/oviduct). Serially collected fecal samples from each female were lyophilized, extracted, and assessed via enzyme immunoassay for oestrogen and progesterone metabolite profiles. Most ocelots (11/13, 85%) and tigers (7/10, 70%) ovulated following gonadotropin treatment, with no difference (P &gt; 0.05) between eCG dosages in mean (± s.e.m.) follicle or corpus luteum (CL) number in ocelots (11.5 ± 4.2 follicles, 2.8 ± 1.0 CL, 400 IU of eCG; 9.9 ± 5.2 follicles, 3.1 ± 1.3 CL, 600 IU of eCG) or tigers (9.0 ± 4.6 follicles, 4.0 ± 2.8 CL, 750 IU of eCG; 12.7 ± 4.4 follicles, 6.0 ± 1.7 CL, 1000 IU of eCG). Similarly, peak fecal hormone concentrations did not differ (P &gt; 0.05) between regimens, except for slightly greater (P ≤ 0.05) progesterone levels for 10 days post-treatment with the higher eCG dose in tigers. Independent t-tests were used for all statistical calculations. One Brazilian ocelot and 1 Amur tiger conceived following LO-AI with freshly collected semen (10 × 106 motile sperm, ocelot; 0.15 × 106 motile sperm, tiger), with each producing 1 viable offspring after an 83-day and 103-day gestation, respectively. These births represent the second ocelot and first tiger produced by LO-AI. Our findings indicate that high and low eCG dosages may be equivalent and that viable offspring can be produced following LO-AI with relatively low sperm numbers in both species. Further refinement of ovarian synchronization and semen cryopreservation methods may be necessary for LO-AI to be applied routinely for ocelot and tiger conservation efforts. Funded by the Institute of Museum and Library Services, Riverbanks Zoo &amp; Garden and Minnesota Zoo; with thanks to Ocelot &amp; Tiger SSP, and participating zoos).

Follicular characteristics and luteal development after follicle-stimulating hormone induced multiple ovulations in heifers1

A protocol based on small doses of FSH was examined for the induction of double or triple (multiple) ovulations in cattle. Ovulation rate, follicular characteristics, and luteal responses were determined. In Exp. 1, three groups of estrous-synchronized, cyclic Holstein heifers were treated once daily, on d 3 to 6 of the cycle, with a FSH product (Folltropin-V): large FSH dose (total of 150 mg; n=18), medium FSH dose (total of 130 mg, n=12), and small FSH dose (total of 80 mg; n=7). Controls received saline (n=6). Prostaglandin F(2α) was injected on d 6, ultrasound-guided aspiration of surplus follicles (if needed) was performed on d 7, and GnRH was injected on d 8 to induce ovulation. The large FSH dose induced growth of more (2.6±0.3, P<0.05) large follicles than controls on d 8; medium and small FSH doses insufficiently stimulated growth of <2 large follicles. Ovulation rates were determined in subgroups of heifers (n=10, 13, 4, and 6, respectively). The large FSH dose induced greater rates (P<0.01) of mostly double and triple ovulations (90% multiple ovulations, 70% double ovulations), most of which (89%) were bilateral, with only 2 out of 10 heifers requiring aspiration of surplus follicles. Medium and small FSH doses induced fewer multiple ovulations (38% and 25%, respectively). Estradiol concentrations on d 8 did not differ among treatments, but the concentration per large follicle in controls was greater (P<0.05) than in FSH treatments. Mean corpus luteum (CL) volume in single-ovulation controls was greater (P<0.05) than that of multiple ovulations in the large FSH group and total CL volume and progesterone concentrations were numerically greater in multiple ovulations. In Exp. 2, the characteristics of follicles aspirated on d 7 from large FSH (n=11) and control heifers (n=10) were compared. Based on estradiol-to-progesterone ratio, 57% of the large FSH-treated follicles were classified as codominant/healthy follicles and 43% as subordinate/early atretic. Although concentrations of estradiol and androstenedione in FSH-treated codominant follicles were less (P<0.05) than in controls, estradiol-to-progesterone ratio indicated that those follicles were steroidogenically active. Finely tuned small doses of FSH administered during the first follicular wave can induce a large incidence of double/triple, mainly bilateral, ovulations in cattle, which may serve as a basis for treatment aimed at promoting twinning in beef cattle.

Contrast Imaging Ultrasound Detects Abnormalities in the Marmoset Ovary

The development of a functional vascular tree within the primate ovary is critical for reproductive health. To determine the efficacy of contrast agents to image the microvascular environment within the primate ovary, contrast ultrasonography was performed in six reproductive-aged female common marmosets (Callithrix jacchus) during the late luteal phase of the cycle, following injection of Sonovue™. Regions of interest (ROIs), representing the corpus luteum (CL) and noncorpus luteum ovarian tissue (NCLOT), were selected during gray-scale B-mode ultrasound imaging. The magnitude of backscatter intensity of CL and NCLOT ROIs were calculated in XnView, post hoc: subsequent gamma-variate modeling was implemented in Matlab to determine perfusion parameters. Histological analysis of these ovaries revealed a total of 11 CL, nine of which were identified during contrast ultrasonography. The median enhancement ratio was significantly increased in the CL (5.54AU; 95% CI -2.21-68.71) compared to the NCLOT (2.82AU; 95% CI 2.73-15.06; P < 0.05). There was no difference in time parameters between the CL and NCLOT. An additional avascular ROI was identified in the ovary of Animal 5, both histologically and by ultrasonography. This cystic ROI displayed a markedly lower enhancement ratio (0.79AU) and higher time parameters than mean CL and NCLOT, including time to peak and time to wash out. These data demonstrate, for the first time, the ability of commercially available contrast agents, to differentiate structures within the nonhuman primate ovary. Contrast-enhanced ultrasonography has a promising future in reproductive medicine.

Relation of reproductive performances and rectal palpation for luteum function of heifers 7 days after estrus

Diagnosis of corpus luteum (CL) function by rectal palpation (RP) has been widely used for recipient selection of embryo transfer (ET), a technology essential for genetic improvements in cattle. To examine the accuracy of RP diagnosis method, the relationship between RP-based CL function and reproductive performance was compared in this study. In Experiment 1, CL of Holstein heifers on day 7 after estrus was classified into functional or hypoplastic by RP, and the results were compared with ultrasonographic (US) images and plasma progesterone (P4) levels. As a result, heifers with functional CL judged by RP had a mean maximum CL diameter of 20.1 ± 3.1 mm on US and a mean P4 concentration of 8.1 ± 2.3 ng/mL. These values were significantly greater than those of heifers with hypoplastic CL (12.4 ± 5.4 mm, 4.0 ± 2.8 ng/mL) (P < 0.001). In Experiment 2, the length of the estrus cycle was examined between functional CL and hypoplastic CL. The rate of heifers with a normal estrus cycle length with 18-25 days was significantly lower with hypoplastic CL than with functional CL (16/24 vs. 43/46, P < 0.01). In Experiment 3, 543 inseminated heifers were similarly classified by CL function by RP 7 days after estrus. The heifers with functional CL showed higher pregnancy rate compared with the heifers with hypoplastic CL (75.2 vs. 47.9%, P < 0.0001). Finally, the CL function of 66 heifers was examined by RP on day 7 post-estrus, and ET was performed in 49 (74.2%) heifers with functional CL. As a result, 27 (55.1%) of them became pregnant. Taken together, these results reconfirm that RP on day 7 after estrus is useful for selection of heifers with functional CL.

Effects of 8-epi-prostaglandin F2 and prostaglandin F2 on serum progesterone concentration and corpus luteum size in ewes

Prostaglandin F2α (PGF2α) is luteolytic in sheep. This study assessed luteolytic ability of an isomer, 8-epi-PGF2α. Ten ewes were estrus-synchronized and blood serum was collected for 12 days and analyzed for progesterone concentration. Ewes were laparoscopically administered 200 µg 8-epi-PGF2α or PGF2α, or placebo in each ovary on day 8 and ovariectomized on day 13. Corpora lutea (CL) were weighed. Serum progesterone was reduced (P < 0.041) by PGF2a on day 9, but recovered to control levels (P = 0.646) by day 10. Interestingly, 8-epi-PGF2a increased (P < 0.050) serum progesterone on days 9, 10, and 12. However, area under curve for serum progesterone between days 8 and 12 did not differ (P = 0.165) among treatments. In ewes administered PGF2a, serum progesterone decreased sharply (P < 0.001) after treatment, but recovered (P = 0.217) to pre-treatment levels by day 11, indicating limited luteolysis after one-time dosage. Mean CL weight did not differ (P = 0.836) among treatments, but weight of largest CL was reduced by 8-epi-PGF2a (P = 0.032) and PGF2a (P = 0.015). One-time, intra-ovarian administration of 8-epi-PGF2a at this dosage did not cause luteolysis. Additionally, serum progesterone is capable of recovery from one-time, intra-ovarian administration of PGF2a. Key words: 8-epi-prostaglandin F2α, luteolysis, prostaglandin F2α.

Características ecográficas do corpo lúteo em gestações iniciais: morfologia e vascularização

the purpose of this research was to evaluate the morphological aspects and vasculature of the corpus luteum (CL) based on ultrasound parameters during early pregnancy and to assess their relationship with early pregnancy loss. this was a prospective cohort study of 90 pregnant patients between 6 and 8 weeks plus 6 days weeks of gestation. We included women at low risk, without acute or chronic systemic disease and with spontaneous conception. use of drugs or smoking, drugs inducing ovulation, history of more than one abortion, no heartbeat visible in the embryo and impossibility of visualization of the corpus luteum. The size, volume, morphological aspects, resistive index, and peak systolic velocity of the corpus luteum were measured by transvaginal sonography. ninety patients were included in the study. Maternal age ranged from 15 to 41 years (mean 28.6 ± 5.8 years). The corpus luteum could be visualized in 87 patients (96.7%), 79 patients had normal pregnancies (90.1%), whereas spontaneous losses occurred in 8 cases (9.9%). In a comparison of the survivors and losses, there was no difference in mean CL diameter (21.8 versus 20.0 mm; p=0.108, Mann-Whitney test), mean CL volume (4.2 versus 3.0 cm³; p=0.076, Mann-Whitney test), mean resistive index (0.55 versus 0,58; p=0.220, Mann-Whitney test), peak systolic velocity (15 versus 15 cm/s; p=0.757, Mann-Whitney test). There was a positive relation between maternal age and resistive index. no apparent correlation was found between the morphological and vascular aspects of the corpus luteum in early normal pregnancies and first-trimester pregnancy losses.

Effect of progesterone supplementation in the first week post conception on embryo survival in beef heifers

Progesterone is essential for establishment and maintenance of pregnancy in mammals. The objective of this study was to examine the effect of elevating progesterone during the different physiological stages of early embryo development on embryo survival. Estrus was synchronized in cross-bred beef heifers ( n = 197, ∼2-years old) and they were inseminated 12–18 h after estrus onset (=Day 0). Inseminated heifers were randomly assigned to 1 of 3 treatments: (1) Control, n = 69; (2) progesterone supplementation using a Controlled Internal Drug Release Device (CIDR) from Day 3 to 6.5, n = 64; or (3) progesterone supplementation using a CIDR from Day 4.5 to 8, n = 64. Body condition (BCS) and locomotion scores (scale of 1–5) were recorded for all animals. Animals with a locomotion score ≥4 (very lame) were excluded. Embryo survival rate was determined at slaughter on Day 25. Conceptus length and weight were recorded and the corpus luteum (CL) of all pregnant animals was dissected and weighed. Supplementation with exogenous progesterone increased ( P < 0.05) peripheral progesterone concentrations, but did not affect embryo survival rate compared with controls. Mean CL weight, conceptus length and conceptus weight were not different between treatments. There was a positive relationship ( P < 0.04) between the increase in progesterone concentrations from Days 3 to 6.5 and embryo survival rate in treated heifers and a similar trend existed between the increase from Days 4.5 to 8 ( P < 0.06). There was also a positive relationship ( P < 0.05) between the progesterone concentration on Day 6.5 and the embryo survival rate in treated heifers. A direct correlation was seen between locomotion score and embryo survival rate, with higher ( P < 0.05) early embryo survival rates in heifers with a lower locomotion score. In conclusion, supplementation with progesterone at different stages of early embryo development increased peripheral progesterone concentration and resulted in a positive association between changes in progesterone concentration during the early luteal phase and embryo survival rate. Supplementation with progesterone had no effect on either CL weight or conceptus size in pregnant animals. Lameness had a significant negative effect on early embryo survival.

Corpus luteum across the first trimester: size and laterality as observed by ultrasound

To study the site and size of the corpus luteum (CL) across the first trimester of pregnancy. Retrospective observational study of 1,806 ultrasound scans performed at 5 to 9 (+6 d) weeks' gestation, as well as a prospective study (n = 313) performed at 10 to 13 (+6 d) weeks' gestation. Four ultrasound practices across Victoria, Australia. Two thousand one hundred nineteen pregnant women. Transvaginal ultrasound. Side and size (diameter) of the CL. At 5 to 9 weeks' gestation, the mean CL diameter was 19.3 mm, with no statistically significant variation across each gestational week. Corpus luteum size then statistically significantly declined at 10 to 13 weeks' gestation, with a mean diameter of 16.85 mm. Of 237 women in whom both ovaries were visualized at 10 to 13 weeks' gestation, a CL was seen in 82% of cases. A statistically significant right-sided bias was observed in both groups (54% at 5-9 wk gestation, 56% at 10-13 wk). The CL remains static in size across 5 to 9 weeks' gestation, then its size declines or it disappears from 10 to 13 weeks. A novel right-sided ovulation bias occurs in human beings.

Response to GnRH on day 6 of the estrous cycle is diminished as the percentage of Bos indicus breeding increases in Angus, Brangus, and Brahman × Angus heifers

Angus ( n = 6), Brangus (5/8 Angus × 3/8 Brahman, n = 6), and Brahman × Angus (3/8 Angus × 5/8 Brahman, n = 6) heifers exhibiting estrous cycles at regular intervals were used to determine if the percentage of Bos indicus breeding influenced the secretory patterns of LH in response to a GnRH treatment on Day 6 of the estrous cycle. Heifers were pre-synchronized with a two-injection PGF 2α protocol (25 mg i.m. Day −14 and 12.5 mg i.m. Day −3 and −2 of experiment). Heifers received 100 μg GnRH i.m. on Day 6 of the subsequent estrous cycle. Blood samples were collected at −60, −30, and −1 min before GnRH and 15, 30, 60, 90, 120, 150, 180, 240, 300, 360, 420, and 480 min after GnRH to determine concentrations of serum LH. Estradiol concentrations were determined at −60, −30, and −1 min before GnRH. On Day 6 and 8, ovaries were examined by ultrasonography to determine if ovulation occurred. On Day 13, heifers received 25 mg PGF 2α i.m. and blood samples were collected daily until either the expression of estrus or Day 20 for heifers not exhibiting estrus to determine progesterone concentrations. There was no effect ( P > 0.10) of breed on ovulation rate to GnRH as well as size of the largest follicle, mean estradiol, and mean corpus luteum volume at GnRH. Mean LH was greater ( P < 0.05) for Angus (7.0 ± 0.8 ng/mL) compared to Brangus (4.6 ± 0.8 ng/mL) and Brahman × Angus (2.9 ± 0.8 ng/mL), which were similar ( P > 0.10). Mean LH peak-height was similar ( P > 0.10) for Brangus (13.9 ± 3.4 ng/mL) compared to Angus (21.9 ± 3.4 ng/mL) and Brahman × Angus (8.0 ± 3.4 ng/mL), but was greater ( P < 0.05) for Angus compared to Brahman × Angus. Interval from GnRH to LH peak was similar ( P > 0.10) between breeds. As the percentage of Bos indicus breeding increased the amount of LH released in response to GnRH on Day 6 of the estrous cycle decreased.

Manipulation of lactation and suckling on the resumption of postpartum reproductive activity in Damascus goats

The reproductive activity of Damascus goats was studied in does that were not allowed to mate (non-lactating does) (Group C) and lactating does with different suckling treatments (Groups A and B). Time resumption of sexual activity was not significantly different between lactating and non-lactating does or between does’ groups of different suckling treatments. All does started to demonstrate estrous behavior during autumn (September). In Groups A, B and C the mean length of the estrous cycle was 19.0±0.6, 19.5±0.3 and 22.0±2.0 days, duration of the estrous period 29.6±3.0, 31.0±5.3 and 25.3±5.8 h, mean corpus luteum (CL) counts 1.6±0.2, 1.8±0.2 and 1.8±0.3, while mean litter size was 1.1±0.1, 1.2±0.2 and 1.3±0.5, respectively. In the three groups an increase in the plasma progesterone concentrations started from summer (mid-June), indicating the occurrence of one or more ovulatory anestrus (silent ovulation). Plasma prolactin levels were higher ( P<0.01) in lactating does than in non-lactating does and at 4 weeks postpartum. Moreover, prolactin levels were significantly higher ( P<0.01) in does suckling their kids than in does being machine milked. Plasma progesterone levels during postpartum were negatively significantly correlated with prolactin levels. The study demonstrated that lactation and suckling lengths have no effect on the resumption of postpartum sexual activity in Damascus goats and that season is the major factor controlling the ovarian activity.