Anovulatory Follicles Research Articles

Effect of intrafollicular administration of PGE2 or PGF2α in early estrus on ovulation, hemorrhagic anovulatory follicles formation, progesterone secretion and pregnancy outcome in the mare

This experiment was performed to evaluate whether intrafollicular treatment of PGE2 or PGF2α administered in early estrus would induce normal ovulation, progesterone production (Experiment 1) and pregnancy (Experiment 2). In Experiment 1, mares in estrus after 2 days of endometrial edema were injected in all largest dominant follicles (28–35 mm in diameter) with 0.5 mL of sterile water containing 500 μg PGE2 (n = 6), 125 μg PGF2α (n = 6) or placebo (n = 7) (Hour 0). Ultrasound examinations were performed daily, until ovulation or anovulation was detected, and daily blood samples were taken for 8 days. In Experiment 2, mares with a dominant follicle ≥35 mm after at least three days of slight-to-moderate endometrial edema, were injected with 500 μg PGE2 diluted in 0.5 mL of sterile water for injection in the follicle (PGE2 group; n = 9 mares and 11 dominant follicles). No puncture was performed in the control group (n = 9 mares and 11 dominant follicles). Mares from both groups were inseminated. In Experiment 1, all mares (6/6) in the PGE2 group ovulated within 24 h of treatment. The mean interval from intrafollicular injection to ovulation was shorter (P < 0.001) in PGE2 mares (24 ± 0 h) than in control mares (77 ± 9 h). Mares from the PGF2α group developed hemorrhagic anovulatory follicles (HAF) more often (7/7) than control mares (2/7); P < 0.05). The progesterone concentration in mares from the PGF2α group was lower (P < 0.004) than control mares in the early post-ovulatory period. The first significant increase in post-ovulatory progesterone concentration occurred earlier (P < 0.05) in mares from the control group than in mares from the PGF2α and PGE2 groups. In Experiment 2, more mares from the control group (7/9, 78 %) became pregnant than from the PGE2 group (2/9, 22 %) (P = 0.015). In conclusion, PGE2 alone induced follicle collapse in all treated mares within 24 h of administrations, while PGF2α blocked ovulation and induced formation of HAFs. However, the post-ovulatory rise in progesterone production was delayed and the fertility reduced in mares with ovulation induced by PGE2 compared to control mares.

The pFSH dose affects the efficiency of in vivo embryo production in Santa Inês ewes

This study compared the follicular growth, superovulatory response, and in vivo embryo production after administering two doses of porcine follicle-stimulating hormone (pFSH) in Santa Inês ewes. The estrous cycle of 36 multiparous ewes was synchronized with the Day 0 protocol and superovulated with 133 mg (G133, n=18) or 200 mg (G200, n=18) of pFSH. Ultrasonographic evaluations of the ovaries were performed, ewes were mated and submitted to non-surgical embryo recovery. Viable blastocysts were stained with Nile Red and Hoechst. The G200 had a greater number of medium and large follicles, as well as a larger size of the third largest follicle. A total of 97.2% (35/36) of the ewes came into estrus and it was possible to transpose cervix in 80.6% (29/36). There were no effects of treatments in the response to superovulation, the proportion of ewes in which was possible to transpose the cervix, the number of corpora lutea, the number of anovulatory follicles, the proportion of ewes flushed with at least one recovered structure, number of recovered structures, number of viable embryos, viability rate, and recovery rate. The G200 ewes were in estrus for a longer period of time than the G133 ewes (54.0 ± 4.5 h vs. 40.3 ± 3.6 h) and produced more freezable embryos (6.5 ± 1.6 vs. 2.3 ± 0.7) than G133. Both doses promoted an efficient superovulatory response and did not affect embryonic lipid accumulation. The dose of 200 mg of pFSH showed greater potential to increase the superovulatory response, as it increased follicular recruitment and the recovery of freezable embryos.

Integration analysis of metabolome and transcriptome reveals the effect of arachidonic acid on hemorrhagic anovulatory follicles in jennies

Compared with other livestock, fertility is low in jennies. Although the majority of jennies shows normal ovulation throughout the year, some jennies display hemorrhagic anovulatory follicles (HAF) in the middle of the winter or summer. Based on our previous results (https://doi.org/10.1111/rda.13883), this research was carried out in from November to January of the next year. In experiment 1, a total of 24 Yangyuan jennies (4∼8 years old) were included, with half of them showing normal preovulatory follicles (control group, Con-G) while the other half had HAF ad diagnosed by transrectal ultrasound (HAF-G). The content of the preovulatory follicle or HAF was collected from each jenny by ultrasound-guided ovum pick-up. The follicular fluid (FF) and granulosa cells (GCs) were used for omics analysis. The results of metabolomics analysis showed that the level of arachidonic acid (AA) was significantly increased in HAF-G (P < 0.05). According to transcriptomics results, the mRNA levels of arachidonate 5-lipoxygenase gene (ALOX5) was significantly increased (P < 0.05) while the level of cytochrome P450 family 2 subfamily J member 2 gene (CYP2J2) was significantly decreased in HAF-G (P < 0.05). However, there was no significant difference between the two groups in the expressionsof prostaglandin-endoperoxide synthase 1 gene (COX1) and COX2 (P > 0.05). Meanwhile, the expressions of FSHR, LHCGR and CYP19A1 were significantly decreased in the HAF-G compared with the Con-G (P < 0.05). In order to pursue the molecular mechanism of AA regulating the functions of granulosa cell, the experiment two was carried out. The mice GCs from antral follicles were cultured in media supplemented with 0, 50 μM or 100 μM AA respectively, and both of cell viability and some genes’ expressions were assayed. The results demonstrate that the survival of GCs and mRNA expressions of FSHR and LHCGR were higher in 50 μM AA group than the control group (P < 0.05). However, when the AA concentration was increased to 100 μM in the medium, the survival rates and expression of FSHR and LHCGR were decreased in comparison to the control group (P < 0.05). Moreover, 100 μM AA increased the expression of ALOX5 and decreased the expression of CYP2J2 compared with 50 μM AA, which was similar to GCs from HAF of jennies. In conclusion, the occurrence of HAF in jennies may be related to the accumulation of AA in follicular fluid of the preovulatory follicles which caused abnormal expression of FSHR, LHCGR and ALOX5 on GCs leading to anovulation and HAF.

Dominant follicle growth patterns and associated endocrine dynamics in anovulatory and ovulatory waves in women.

Growth patterns and associated endocrine profiles were compared between dominant anovulatory (ADF) and ovulatory follicles (OvF) developing from different waves within and between menstrual cycles in women. Follicular mapping profiles of 49 healthy women of reproductive age and blood samples were obtained every 1-3 days. Sixty-three dominant follicles were classified into wave 1 (W1ADF; n = 8) and wave 2 (W2ADF; n = 6) anovulatory follicles and wave 2 (W2OvF; n = 33) and wave 3 (W3OvF; n = 16) ovulatory follicles. Comparisons were made between W1ADF and W2ADF, W2ADF and W2OvF, and W2OvF and W3OvF. The waves were numbered 1, 2, or 3 based on when the waves emerged relative to the preceding ovulation. W1ADF emerged closer to the preceding ovulation, and W2ADF emerged in the late luteal or early follicular phase. The interval from emergence to maximum diameter was shorter for W2ADF than W1ADF and for W3OvF than W2OvF. Selection of W3OvF occurred at a smaller diameter compared to W2OvF. W1ADF regressed at a faster rate than W2ADF. Also, W1ADF were associated with lower mean FSH and higher mean estradiol than W2ADF. In contrast, W3OvF were associated with higher FSH and LH compared to W2OvF. However, W2OvF were associated with higher progesterone than W3OvF. This study contributes to the understanding of the physiologic mechanisms underlying selection of the dominant follicle, ovulation, and pathophysiology of anovulation in women, as well as optimization of ovarian stimulation protocols for assisted reproduction.

SUPEROVULATORY RESPONSE IN DAIRY COWS AFTER APPLICATION OF ECG

PURPOSE: The aim of the present study was to determine the follicular dynamics and superovulatory response in dairy cows after the administration of eCG. METHODS: The study included 6 Holstein cows bearing CL in the ovaries treated with PGF2α for estrus induction. After estrus detection daily ultrasound scanning to monitor the dominant follicle of the first follicular wave was made. Superovulation treatment (2500 IU eCG and two doses of 500μg PGF2α analog on the 48th and 60th hour after the eCG injection) started at the emergence of the second follicular wave. The number and diameter of the follicles ≥ 5 mm, the number of corpora lutea and anovulatory follicles (AF) and the ovulation rate (OR) were estimated. RESULTS: At the start of the superovulation treatment (SO) the average number and diameter of the medium and large follicles were 2.7±1.2 and 0.67±0.13 cm and 1.6±0.5 and 1.45±0.28 cm, respectively. There were high positive correlations between the days of the treatment and number of large and medium follicles (r = 0.80, P = 0.018 and r = 0.75, P = 0.03). The average number of large follicles on day 5 was greater than those at the start of SO. On day 8 the OR was 55.9% and the difference between anovulatory follicles and corpora lutea was not significant. CONCLUSIONS: The used protocol provided acceptable OR, but the average number of AF (44.1%) remained high. Ultrasonography could be used to monitor the first dominant follicle and the emergence of a new follicular wave.

The Use of Ultrasound for Monitoring the Relationship Between the Diameter of the Dominant Follicle, The Inter-ovulatory Interval, and Follicular Waves in Dairy Cattle

The aim of the current study was to use ultrasound imaging to follow the follicular dynamics in dairy cows and to determine the relationship between the diameter of the dominant follicle (DF), the life span of the corpus luteum (CL), interovulatory interval (IOI), and the number of follicular waves. Twenty nine Holstein normal cyclic cows 60 days postpartum were used in this study. The ovaries of the experimental cows were scanned for the DF and CL every three days from ovulation to ovulation. Cows undergo the Ovsynch program to unify the beginning of the ovulation per cycle. The results revealed that, cows that exhibit the two wave patterns have a longer time of IOI than a cow with a one wave pattern (P&lt;0.05), and a shorter length of IOI than cows with three follicular wave patterns (P&lt;0.05). The duration of the DF growth phase in the first follicular wave (Wave 1) was prolonged in a cow that exhibited a one-wave pattern than in the cows that exhibited the two or three-wave patterns (p&lt;0.05). The maximum diameter of DF for a single follicular wave pattern (17.6 ± 0.67 mm). The maximum diameter of the anovulatory follicle in the two-wave patterns (12 ± 2.53 mm) was larger than the maximum diameter of the anovulatory follicle (10.75 ±1.33 mm, p&lt;0.05) of wave one in cows that exhibited three-wave patterns. The lifespan of the corpus luteum in the one-wave pattern was significantly shorter (p&lt;0.05) than in two-wave patterns and three-wave patterns. The length of the IOI was positively increased with the number of the follicular wave and the length of the luteal phase but was negatively related to the diameter of the first dominant follicle in the wave and the duration of the (DF) growth phase in the first wave (p&lt;0.05). In Conclusion, these results demonstrate that the length of the IOI in cows exhibiting the two-wave patterns is shorter than in cows exhibiting three-wave patterns due to the larger diameter of the dominant follicle in wave one, the longer duration of the DF growth phase in the first wave, and the shorter life span of the CL in the cows exhibiting two-wave patterns than in cows exhibiting three-wave patterns.

The effect of dexamethasone and flunixin-meglumine on ovulation, endometrial oedema, and inter-ovulatory interval length in the mare

The use of flunixin-meglumine (a potent non-steroidal anti-inflammatory drug) during the critical period of intrafollicular prostaglandin production before ovulation (24 and 36 h after hCG treatment) results in a high rate of ovulatory failure and formation of haemorrhagic anovulatory follicles (HAF) in the mare. Dexamethasone is commonly used to prevent persistent mating-induced endometritis in susceptible mares, but the effect on ovulation blockage within the pre-ovulatory critical window of intrafollicular prostaglandins production following hCG administration has not been determined. Six mares were followed during four consecutive cycles in a crossover design; once in oestrus with a follicle of >32 mm in diameter, mares were treated with hCG (Hour 0) and assigned to one of 4 groups randomly: 1) FM, mares received 1.7 mg/kg flunixin-meglumine at Hour 24 and 36; 2) CON, mares received no further treatment. 3) DEX1, mares received 0.1 mg/kg dexamethasone at Hour 24, and 4) DEX2, mares received 0.1 mg/kg dexamethasone at Hour 24 and 36. For all groups, ovulation and HAF rates, endometrial oedema profiles and the inter-ovulatory intervals (IOI) were determined and compared statistically. All CON and DEX mares ovulated normally and did not form any HAF. On the contrary, FM mares developed a HAF in 83% of cycles (P < 0.01). The endometrial oedema score was lower following DEX administration than FM (P < 0.05). The mean IOI was longer (P < 0.05) in DEX1 and DEX2 groups (26.5 and 26 days, respectively) than in CON and FM groups (21.5 and 22 days, respectively). In conclusion, dexamethasone treatment given either once or twice during the critical window of hCG-induced ovulation did not block or delay ovulation, but had a similar ovulation rate than untreated control mares. However, the inter-ovulatory intervals of dexamethasone treated mares was longer than control and FM treated mares. Finally, dexamethasone treatment was more effective in reducing endometrial oedema than FM.

OR06-4 Women With Obesity Display Defects in Follicular Recruitment, Selection, and Dominance Alongside Luteal Phase Dysfunction During Natural Ovulatory Cycles

Abstract Although obesity is closely associated with reproductive dysfunction, many women with obesity remain eumenorrheic. The degree to which obesity affects menstrual cycle characteristics in this population is limited to endocrine assessments with few data available on how endocrine aberrations align with defects in antral follicle development.We have previously shown alterations in the distribution of recruitable (2-5mm) versus selectable (6-9mm) follicles in those with obesity that were associated with decreased gonadotropin and progesterone production despite normal menstrual cycle length. The objectives of the present study were to further contrast follicular growth and endocrine dynamics between obese and non-obese eumenorrheic women with the goal of determining any alterations in distinct events in folliculogenesis. 21 non-obese (total percent body fat &amp;lt;35%) and 21 obese (total percent body fat ≥35%) reproductive age females with regular menstrual cycles (21-35d) were evaluated by serial ovarian transvaginal ultrasonography and venipuncture every-other-day for one complete inter-ovulatory interval (IOI). The number and diameters of all follicles ≥2mm at each visit were documented offline using the Grid Method. Growth profiles of individual follicles which grew to ≥7mm were assessed using the Identity Method to characterize antral follicle recruitment, selection, and ovulation. Clinical, morphologic, and endocrine features were compared across groups using t-tests and mixed models. Women with obesity exhibited fewer recruitment events versus non-obese women (1±0.6 vs. 2±0.9; p=0.010). They also had fewer selectable follicles (4±3 vs. 8±6 follicles/participant, p=0.022) which grew faster but remained static longer and regressed slower (all growth rates, p&amp;lt;0.05) compared to their non-obese counterparts. Anti-Mullerian hormone levels were lower in the obese versus non-obese group (4.40±3.01 vs. 5.94±2.49ng/mL, p=0.023). Of the selectable follicles, fewer progressed to ≥10mm in the obese versus non-obese group (1±0.7 vs. 2±0.8 follicles, p=0.030) with ultimately fewer anovulatory follicles achieving dominance (0±0.7 vs. 1±0.9 follicle, p=0.029). Ovulatory follicles in the obese group were selected at smaller diameters (7.5±1.6 vs. 9.5±1.9mm, p=0.001) versus their non-obese counterparts. However, the kinetics of dominant follicle growth were similar between groups. Post-ovulation, progesterone concentrations across the luteal phase were lower in women with obesity (4.95±3.34 vs. 7.85±5.74ng/mL, p=0.001) and the prevalence of luteal phase defects (LPDs) higher versus non-obese women, defined by either integrated (76 vs. 29%, p=0.002) or maximum (71 vs. 24%, p=0.002) progesterone levels. Eumenorrheic women with obesity display evidence of suppressed follicle dynamics as evidenced by fewer recruitment events, selectable follicles, and anovulatory dominant follicles. LPDs are more prevalent in women with obesity during natural ovulatory cycles which may underlie subfertility in this population. A smaller size at selection suggests premature responsiveness to luteinizing hormone which may result in suboptimal luteinization. Further studies are needed to elucidate the degree to which these defects impact fertility and fecundity in our increasingly obese demographic. Presentation: Saturday, June 11, 2022 12:15 p.m. - 12:30 p.m.

Ultrasonographical and hormonal comparative between true and postpartum anestrus of cows in south of Iraq

Anestrus is one of the major reproductive problems. A total of 218 local breed cows were diagnosed as 105 cows with true anestrus and 113 cows with postpartum anestrus. The results indicated that most cases of postpartum anestrus were concentrated from December to May, while the true anestrus occurred from May to September. The most important causes that were diagnosed by ultrasound for true anestrus cases were inactivity of the ovaries and anovulatory follicles. A high percentage of postpartum anestrus cases were suffered from luteinizing cysts, ovarian inactivity. Hormonal assay for inactive ovaries in true and postpartum anestrus cases revealed a significant decrease (p&lt;0.05) in the levels of estrogen, progesterone, FSH and LH. While the hormonal results of postpartum anestrus cases revealed a significant decrease (p&lt;0.05) in the estrogen with a significant increase (p&lt;0.05) in the progesterone in case of luteal cyst, persistent corpus luteum and cystic corpus luteum which accompanied by a significant increase (p&lt;0.05) in the prolactin .The ultrasonographical features for true anestrus showed an increase in echo rates for ovaries. In postpartum anestrus cases the luteal cyst revealed 2.88-2.90cm follicle like structure. While the cases of persistent corpus luteum showed 1.15cm-1.75cm dense theca tissue.

Overfeeding Extends the Period of Annual Cyclicity but Increases the Risk of Early Embryonic Death in Shetland Pony Mares.

Simple SummaryObesity has been associated with altered reproductive activity in mares and may negatively affect fertility. To examine the influence of long-term high-energy (HE) feeding on fertility, Shetland pony mares were fed a diet containing 200% of net energy (NE) requirements during a three-year study. The incidence of hemorrhagic anovulatory follicles (HAF) and annual duration of cyclicity were compared to those in control mares receiving a maintenance diet. Day-7 embryos were flushed and transferred between donor and recipient mares from both groups; the resulting conceptuses were collected 21 days after transfer to assess conceptus development. HE mares became obese, and embryos recovered from HE mares were more likely to succumb to early embryonic death. The period of annual cyclicity was extended in HE compared to control mares in all years. The incidence of HAFs did not consistently differ between HE and control mares. No differences in embryo morphometric parameters were apparent. In conclusion, consuming a HE diet extended the duration of cyclicity, and appeared to increase the likelihood of embryos undergoing early embryonic death following embryo transfer.Obesity has been associated with altered reproductive activity in mares, and may negatively affect fertility. To examine the influence of long-term high-energy (HE) feeding on fertility, Shetland pony mares were fed a diet containing 200% of net energy (NE) requirements during a three-year study. The incidence of hemorrhagic anovulatory follicles (HAF) and annual duration of cyclicity were compared to those in control mares receiving a maintenance diet. Day-7 embryos were flushed and transferred between donor and recipient mares from both groups; the resulting conceptuses were collected 21 days after transfer to assess conceptus development. HE mares became obese, and embryos recovered from HE mares were more likely to succumb to early embryonic death. The period of annual cyclicity was extended in HE compared to control mares in all years. The incidence of HAFs did not consistently differ between HE and control mares. No differences in embryo morphometric parameters were apparent. In conclusion, consuming a HE diet extended the duration of cyclicity, and appeared to increase the likelihood of embryos undergoing early embryonic death following embryo transfer.

Fixed-time artificial insemination protocols on brazilian locally adapted breed gilts on ovulatory response and embryo production.

The aim of this study was to use estrus synchronization protocols to favor fixed-time artificial insemination and consequently fixed-time embryo collection, and increase embryo production using eCG, in gits. In a cross over design, nine Piau breed gilts were subjected to 18 days of oral progesterone; P4 group did not receive any further; GnRH group received 25µg of GnRH 104 hours after the final application of P4; and eCG+GnRH group received 1000IU of eCG 24 hours after the final P4 in addition to GnRH for subsequent embryo collection, that was performed six days after first AI, by laparotomy. Artificial insemination was performed after 12 and 24 hours of estrus in P4 group, and 128 and 144 hours in GnRH and eCG+GnRH groups. The number of CL (8.6±3.9; 8.3±2.1; 26.7±15.0) and anovulatory follicles (4.3±3.7; 3.9±3.9; 17.2±9.5) was higher in the eCG+GnRH gilts (P<0.05). However, the use of 1000 IU of eCG reduced (P<0.05) the number of total structures (5.2±3.6; 5.1±3.1; 1.7±2.7), viable embryos (5.0±3.5; 4.8±3.3; 0.4±0.7), freezable embryos (3.6±3.4; 3.3±3.8; 0.1±0.3) and recovery rate (63.7±38.9; 58.6±24.7; 5.38±9.5). P4 and GnRH protocols were effective in the production and recovery of embryos. However, the use of 1000 IU of eCG, 24 hours after P4, was not effective in promoting the production of embryos, although the animals had superovulated.

Laparoscopic drainage of an ovarian haematoma in a Martina Franca jenny (Equus asinus)

An 11-year-old Martina Franca jenny (Equus Asinus), involved in a breed recovery programme organised by the Puglia Region, was referred to the University’s Veterinary Teaching Hospital for a mass formation detected on the surface of the right ovary. The subject had regular oestrous cycles, but gestation loss was reported in the anamnesis. The ovarian mass was monitored by transrectal palpation and ultrasonography. In the differential diagnosis, an ovarian haematoma, a haemorrhagic anovulatory follicle and a granulosa cell tumour were hypothesised; a surgical resolution with laparoscopic access was chosen. During surgery, about 750 ml of haemorrhagic fluid was drained, confirming the suspect of the ovarian haematoma. After resolution, the jenny was inseminated, eventually giving birth to a live and viable foal. Usually, an ovarian haematoma spontaneously regresses, but, in this report, the lesion remained stable for more than two months, leading to the decision of the surgical resolution. Furthermore, to the authors’ knowledge, this lesion has never been reported in donkeys.

Update on the management of the anovulatory follicle in horses

Background: Anovulatory follicles are those that reach the correct size but then fail to ovulate. Two pathological forms of anovulatory follicle exist in horses: persistant anovulatory follicles and haemorrhagic anovulatory...

Power and colour Doppler ultrasonography for evaluation of the ovarian and uterine haemodynamics of infertile mares

The present study was undertaken to investigate the haemodynamics of the ovary and uterus in infertile mares using power and colour Doppler ultrasonography. Forty-seven Arabian mares were handled in the current work through several examinations. Based on the breeding history complaints, physical, vaginal examination and Doppler examination, 12 mares were found to be suffering from abnormal ovarian structures (Experiment I). In addition, nine mares with normal cyclic activity were kept as control. Another 16 mares were found to suffer from abnormal uterine conditions and 10 mares with normal uterine findings served as control (Experiment II). Blood flows to the anovulatory follicle, ovarian inactivity, granulosa cell tumour were compared to those to the dominant follicle and luteal blood flow. Uterine blood flow of cysts, abnormal uterine fluids (endometritis) during estrus and diestrus were compared to normal uterine vascularisation during estrus, diestrus and post-mating. Results showed that granulosa cell tumour had the highest red colour blood flow and total colour blood flow area. Blue colour blood flow area of the corpus luteum was higher compared to the dominant follicle and inactive ovary. Uteri with uterine cyst and abnormal uterine fluids during estrus of infertile mares had high red colour blood flow, blue colour blood flow and power blood flow areas compared to normal uterus during estrus. It could be concluded that Doppler ultrasound could distinguish between normal ovaries with normal or abnormal structures. Moreover, the increased uterine blood flow area of mares with abnormal fluids in their uteri (endometritis) and uterine cysts could be distinguished by comparison to the normal uterine blood flow during estrus.

Effects of follicular ablation and induced luteolysis on LH and follicular fluid factors during the periovulatory period in mares

Haemorrhagic anovulatory follicles (HAFs) are the most common pathological anovulatory condition in the mare. To enhance understanding of the physiopathology of HAFs, the aim of the present study was to determine the effects of an induced-follicular wave on LH concentrations and follicular fluid factors relevant to the ovulatory process. Mares were allocated to treatment or control groups (n = 7/group) in a crossed over design during 14 oestrous cycles with a period of one cycle occurring when there were no treatments between the times when treatments were administered. In the treatment group, all antral follicles ≥8 mm were ablated on Day 10 after ovulation followed by administration of a luteolytic dose of PGF2α. All mares of both groups were treated with 1500 IU of hCG when a follicle ≥32 mm was detected (Hour 0), and follicular fluid was aspirated 35 h later. Blood samples were collected every 48 h from Day 10 until Hour 0 from all mares. Follicular fluid was assayed for PGE2, estradiol and progesterone. Plasma was assayed for LH concentrations. A follicular wave followed follicle ablation in the treated mares. Concentrations of LH were greater (P = 0.05) in mares ot the treatment compared with control group. Concentrations of PGE2, estradiol and progesterone in follicular fluid did not differ between groups (P > 0.05). Treatment resulted in an earlier increase in circulating LH, however, there was no effect on concentrations of intra-follicular PGE2, estradiol or progesterone in hCG-stimulated preovulatory follicles.

Seasonal variation in equine follicular fluid proteome

BackgroundProteomic studies of follicular fluid (FF) exist for several species, including the horse; however, the seasonal influence on FF proteome has not been explored in livestock. The application of high-throughput proteomics of FF in horse has the potential to identify seasonal variations of proteins involved in follicle and oocyte growth.MethodsThis study (i) profiles the proteomes of equine FF collected from dominant growing follicles during the spring anovulatory season (SAN), and spring (SOV), summer (SUM), and fall (FOV) ovulatory seasons; and (ii) identifies season-dependent regulatory networks and associated key proteins.ResultsRegardless of season, a total of 90 proteins were identified in FF, corresponding to 63, 72, 69, and 78 proteins detected in the SAN, SOV, SUM, and FOV seasons, respectively. Fifty-two proteins were common to all seasons, a total of 13 were unique to either season, and 25 were shared between two seasons or more. Protein-to-protein interaction (PPI) analysis indicated the likely critical roles of plasminogen in the SAN season, the prothrombin/plasminogen combination in SUM, and plasminogen/complement C3 in both SOV and FOV seasons. The apolipoprotein A1 appeared crucial in all seasons. The present findings show that FF proteome of SUM differs from other seasons, with FF having high fluidity (low viscosity).ConclusionsThe balance between the FF contents in prothrombin, plasminogen, and coagulation factor XII proteins favoring FF fluidity may be crucial at the peak of the ovulatory season (SUM) and may explain the reported lower incidence of hemorrhagic anovulatory follicles during the SUM season.

Environmental effects and repeatability of the follicular diameter in mares

ABSTRACT The objective of this study was to evaluate the effect of environment on follicular diameter and repeatability of the size of preovulatory follicles of mares. Temperature, rainfall, and photoperiod were measured, and their effects were evaluated on follicular dynamics. Data were studied by analysis of variance of follicular size and environment traits. During the five years, 7% double ovulations and 159 anovulatory follicles were recorded. Mean preovulatory follicle diameters of left and right ovaries were 39.3±3.8 and 39.2±3.5 mm [...]

97 Ovulation induction in anovulatory southern white rhinoceros (Ceratotherium simum simum)

The extant Rhinocerotidae family is experiencing threats in the wild, making captive populations important genetic reservoirs for species survival. Because each species faces distinct challenges in captivity, populations are not self-sustaining. Therefore, assisted reproductive technologies (ART) such as AI will be necessary to maintain or increase captive genetic variation. Captive-born female white rhinoceros (Ceratotherium simum simum) have low reproductive rates and apparent acyclicity is a common issue. Although females fail to ovulate and progesterone remains at baseline levels, follicle growth may occur and ovulation can be induced with exogenous hormones. Female southern white rhinos (n=6) housed as a bachelorette group were determined to be ovulatory (n=1) or anovulatory (n=5) by serial ultrasound and fecal progesterone (P4; ng g−1) analysis. However, all anovulatory females grew follicles beyond preovulatory size, which then regressed. At the time of study, when follicles were preovulatory size (35.4±1.2 mm; mean±SD), anovulatory females (n=4) were induced to ovulate (n=11) with a gonadotropin releasing hormone (GnRH) agonist (4.5mg, SucroMate™; Bioniche Animal Health, Bogart, GA, USA) in a single intramuscular injection. Nine treatments resulted in ovulation (81.8%), all between 36 and 48h post-treatment, while 2 hemorrhagic anovulatory follicles (18.2%; HAF) formed, both in the same female. Ovulations were confirmed by disappearance of the follicle by 48h and P4 elevation above baseline was coincident with corpus luteum (CL) and HAF formation. All resulting luteal structures were included in analysis. Follicle growth was permitted to proceed without GnRH treatment between inductions (n=6); dominant follicles grew beyond preovulatory size (43.8±6.1mm) followed by regression and growth of another preovulatory follicle that was subjected to GnRH treatment. Data were analyzed by R studio (ver. 1.1.383). Luteal phases were characterized as “short” (&amp;lt;50 days) or “long” (&amp;gt;50 days). Only P4 above baseline (days) was significantly different (P&amp;lt;0.05) between long and short cycles. Other cycle parameters, such as CL visibility (days), time from ovulation to P4 above baseline (days), maximum P4 (ng g−1), and maximum luteal size (mm), were not significantly different between cycle types. Both cycle types were observed following both spontaneous (short, n=5; long, n=3) and induced ovulations (short, n=8; long, n=3). These data provide additional insight into the differences between long and short cycles and that GnRH is a reliable and effective method to overcome anovulation in SWR. We also prove that long cycle lengths are not necessarily indicative of early pregnancy loss, as has been previously suggested. Taken together, this information can enhance captive breeding efforts and the genetic diversity of the ex situ, SWR insurance population.

121 Ovulatory response to gonadotropin-releasing hormone relative to day and diameter of dominant follicle during the first follicular wave in Beetal goats

In Beetal goats under subtropical conditions, ovulatory response of first-wave dominant follicle based on diameter and day of oestrous cycle is unknown to date. The objective of this study was to evaluate the ovulatory response to gonadotropin-releasing hormone (GnRH) relative to day and diameter of dominant follicle during the first follicular wave in Beetal goats. Fifty goats were synchronized using a single dose of prostaglandin F2α (75 µg; D+ cloprostenol, Fatro, Italy), and scanned every 6 hours for ovulation using a 7.5-MHz trans-rectal transducer (Honda HS: 1500, Japan). Following ovulation (Day 0), goats (n=40; 10/day) were given GnRH (25µg lecirelin, Fatro, Italy) on Days 2, 4, 6, and 8 of oestrous cycle. Follicular dynamics was monitored daily from D 0 until GnRH, and every 4 hours after GnRH until ovulation. Ovulation frequency relative to day and dominant follicular diameter was analysed by binary logistic regression, whereas diameter of dominant follicle at time of GnRH, ovulation time, time of wave emergence and growth rate of dominant follicle following GnRH were analysed by one-way ANOVA and independent sample t-test (SPSS 20, IBM Corp., Armonk, NY, USA). Eighty percent of the goats ovulated within 74.7±1.3h after prostaglandin F2α. Overall, 37% (14/38) of the goats ovulated following GnRH within 12.0±1.5h. Ovulations (%) following GnRH were higher (P=0.03) on Day 4 than 2 (60 v. 10%; i.e. 14 times higher than Day 2) and decreased gradually from Day 4 to 8 (P&amp;gt;0.05). Similarly, ovulations following GnRH were higher (P=0.00) in first-wave dominant follicles having diameter 6.1-7.0mm than those having less than 6.1mm (88v. 23%; i.e. 24 times higher than &amp;lt;6.1mm). Ovulations (%) decreased as the diameter of dominant follicle increased from 6.1-7.0mm (P&amp;gt;0.05). Diameters of ovulatory follicles at time of GnRH between Day 2, 4, 6, and 8 were not different (P&amp;gt;0.05). Regardless of day of GnRH treatment, diameter of ovulatory v. anovulatory follicles differed (6.44±0.03v. 5.1±0.4 mm; P=0.00). Overall, growth rate of dominant follicles following GnRH was 0.2±0.11mm and did not differ between ovulatory and anovulatory goats (0.29±0.13v. 0.13±0.15 mm; P&amp;gt;0.05). Interval to the emergence of a new wave following GnRH was prolonged for Day 4 compared to Day 2, 6, and 8 (i.e. 22v. 8, 11, and 12 h; respectively, P&amp;lt;0.05). In conclusion, GnRH treatment at Day 4 resulted in maximum ovulations as the first-wave dominant follicle reached a size of 6.1 to 7.0 mm.

Treated and untreated anovulation associated with ovarian and uterine blood flow in Arabian mares (a case study)

To investigate the development of treated and untreated hormonal anovulatory follicles (AnOV) associated with uterine and ovarian vascularization, rectal Doppler ultrasound of seven Arabian mares was performed before and after the development of an AnOV. In addition to measuring the diameter, area and volume of the follicle, daily colour and power Doppler scans were analysed in order to measure red, blue and power blood flow areas in pixels. Serum levels of estradiol (E2), progesterone (P4), leptin, insulin-like growth factor-I (IGF-1) and nitric oxide (NO) were measured as well. The diameter (cm), area (cm2), volume (cm3), area in pixels, antral area in pixels, circumference, and percentage change in circulation of the AnOV progressively increased (P&lt;0.0001) after the disappearance of uterine oedema compared to the values obtained during oedema. The blue, total colour and power areas of the AnOV increased after the disappearance of uterine oedema (P&lt;0.0001). When the antral area was excluded, the percentage of the granulosa layer in the colour and power Doppler decreased after the disappearance of uterine oedema. The ipsilateral uterine horn and uterine body had significantly (P&lt;0.0001) high blue and red blood flow vascularization areas in the presence of uterine oedema. The AnOV was associated with low P4, IGF-1 (P&lt;0.001), and leptin (P&lt;0.05). Treatment of the AnOV follicle with GnRH resulted in its luteinization and induced ovulation 9 and 30 days later. It can be concluded that an abrupt increase in blood flow due to decreased progesterone and E2 and increased IGF-1 causes anovulation. The absence of oestrous behaviour and high uterine-oedema-associated follicular and ipsilateral uterine horn vascularization are predictors of ovulation failure.