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1.
Theriogenology ; 218: 79-88, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38301510

RESUMEN

The aim of the present study was to evaluate: 1) the association between AMH, AFC, superovulatory response and embryo yield in sheep; and 2) the effect of FSH treatment length during superstimulation of the first follicular wave on ovarian response and embryo yield, particularly in ewes with low and high AMH. The experiment was performed on 63 Polled Dorset ewes that received an ovarian superstimulatory treatment during the first follicular wave (Day 0 protocol). Ewes were administered a total dose of 240 mg of FSH distributed in six (6-dose regimen, n = 30) or eight (8-dose regimen, n = 33) decreasing doses administered 12 h apart. On Day -9 (random stage of the estrous cycle) and Day 0 (day of the first FSH dose) ovarian ultrasonography was performed and blood samples were collected for AFC and AMH determinations, respectively. A weak positive correlation between AMH and small AFC (follicles <4 mm) was observed (r = 0.23; P = 0.07), and AMH concentration was positively correlated (r = 0.29; P < 0.05) with the number of corpora lutea (CL) determined at embryo collection (i.e., 6 d after insemination). The length of FSH treatment tended (P = 0.06) to affect the ovarian response, such that the number of CL was greater in 8-dose than 6-dose treated ewes, while no differences (P > 0.10) in embryo yield outcomes were observed. For further analysis, ewes were classified into low (<7 ng/mL) and high (>10 ng/mL) serum AMH. In high AMH ewes, there were no differences (P > 0.05) in the number of CL nor embryo yield between the 6-dose and 8-dose treatment (e.g., 7.8 ± 2.4 and 8.3 ± 2.5 transferable embryos, respectively; P = 0.92). Conversely, for low AMH ewes, fertilized ova and embryo yield were greater (P ≤ 0.05) for ewes receiving the 8-dose than the 6-dose superstimulatory treatment (e.g., 8.4 ± 2.8 vs. 2.7 ± 0.9 transferable embryos, respectively, P ≤ 0.05). In conclusion, embryo production in poor responding ewes with low low circulating AMH is improved by extending the superstimulatory treatment length from 6 to 8 FSH doses.


Asunto(s)
Hormona Folículo Estimulante , Folículo Ovárico , Femenino , Animales , Ovinos , Folículo Ovárico/fisiología , Hormona Folículo Estimulante/farmacología , Ovario , Cuerpo Lúteo , Superovulación
2.
Theriogenology ; 217: 151-158, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38277797

RESUMEN

This study evaluated the effects of antral follicle count (AFC) in female cattle on offspring characteristics. Recently calved multiparous Bos indicus cows (Nelore; n = 222) were evaluated using ultrasonography on random days of their estrous cycle to determine the AFC and were classified into "low" (≤15 follicles), "intermediate" (≥16 and ≤ 29 follicles), and "high" (≥30 follicles) AFC groups. Weight and scrotal circumference (SC) of male offspring from these cows (n = 127) were determined from 20 to 27 months, and the data were added to a genetic evaluation program (economic total genetic merit, MGTe and TOP value) that uses the kinship matrix to evaluate the genetic relationship between animals. The AFC of female offspring from these cows (n = 95) was evaluated to analyze the relationship between the AFC of mothers and daughters. The effects of maternal AFC on the genetic merit of male and female offspring were analyzed using GLIMMIX and GLM, respectively. Correlations were assessed using the Pearson's coefficient. Male offspring of cows with high AFC had superior MGTe (P = 0.005) and TOP values (P = 0.01) than those from cows with low AFC. Additionally, the AFC of mothers was positively correlated with MGTe (R = 0.33; P < 0.0001) and negatively correlated with TOP values (R = -0.32; P < 0.0001). The SC (P = 0.01), but not body weight of the offspring (P = 0.46) was affected by maternal AFC. The daughters' AFC were correlated (R = 0.29; P = 0.004) with mothers' AFC and were influenced by maternal (P = 0.05) but not paternal (P = 0.77) effect. In conclusion, cows with high AFC produced males with greater MGTe, superior TOP values and higher SC. Maternal AFC did not influence the weight of male offspring but was correlated with the AFC of daughters.


Asunto(s)
Ciclo Estral , Folículo Ovárico , Masculino , Bovinos/genética , Femenino , Animales , Folículo Ovárico/diagnóstico por imagen , Ultrasonografía
3.
Reprod Domest Anim ; 58(12): 1766-1769, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37814463

RESUMEN

The objective of this research was to investigate the diagnostic accuracy of post-mortem ultrasound in antral follicle count (AFC) determination and compare it with visual AFC in grazing crossbred Holstein cows, at high altitude in Ecuador. Pre-mortem blood from 80 cows was collected, and AFC and ovarian characteristics were analysed post-mortem by ultrasound and visual techniques. AFC counts were stratified as high, medium or low by terciles. Mean AMH concentration in pre-mortem blood was 280.1 ± 15.53 pg/mL. The AFC obtained by visual inspection (26.9 ± 9.49 follicles) was 23.8% higher than by ultrasound (20.5 ± 7.53 follicles) in all ovaries. Body condition score, age and weight of the cattle did not interact with the count technique. In the low AFC group, visual inspection and ultrasound provided similar AFC results. However, in the Medium- and High-AFC groups, AFC by ultrasound was 14.9% lower than AFC by visual inspection. We confirm that ultrasound can be used with great accuracy for AFC >3 mm (close to the resolution limit) in grazing crossbred Holstein cows at high altitude.


Asunto(s)
Altitud , Folículo Ovárico , Femenino , Bovinos , Animales , Folículo Ovárico/diagnóstico por imagen , Ovario/diagnóstico por imagen , Ultrasonografía/veterinaria , Hormona Antimülleriana
4.
J Ultrason ; 23(93): e73-e79, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37520745

RESUMEN

Aim: We sought to create and describe a self-made simulator designed and created for teaching purposes: a high-fidelity ultrasound phantom for demonstrating antral follicle count, ultrasound supervision of controlled of ovarian stimulation, and ultrasound-guided oocyte retrieval. Materials and methods: The uterus and ovaries of the ultrasound phantom were made from beef tongue, a male condom, latex gloves, cotton suture threads, bi-distilled water, and ultrasound gel. The components were placed in a pelvis created using three-dimensional (3D) printing. The phantom was presented to and evaluated by a group of 14 physicians pursuing a postgraduate course in reproductive medicine. Two training stations were structured: one to simulate antral follicle count and controlled ovarian stimulation and the other to simulate ultrasound-guided oocyte retrieval. Future specialists were requested to complete a feedback questionnaire evaluating the self-made simulator and the two practice stations. Results: The transvaginal ultrasound phantom was successfully created, making it possible to simulate antral follicle count, ultrasound control of ovarian hyperstimulation, and oocyte retrieval, and to capture ultrasound images. A review of the answers provided in the feedback questionnaire showed that the phantom had a good appearance and design, was realistic, helped to improve motor coordination, and could be a useful tool in the training of specialists in assisted reproduction. Conclusion: This phantom was designed to enable instruction and practice in the evaluation of ovarian follicles and ultrasound-guided oocyte retrieval in a supervised training environment. This self-made simulator is proposed as a training tool that could be included in the curricular structure of residency and postgraduate programs in reproductive medicine.

5.
Arq. bras. med. vet. zootec. (Online) ; 74(3): 390-398, May-June 2022. tab, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1383782

RESUMEN

Prepubertal Nelore (G-N = 15) and crossbred Nelore x Aberdeen Angus heifers (G-NA = 15) were used for this study. AFC, live weight, body condition score (BCS), ovary and dominant follicle (DF) diameters were determined in each animal. Puberty induction was performed by insertion of a 4th use progesterone device (D0) which was removed on D12. Also, 1 mg estradiol benzoate was administered, and estrus intensity was classified (D12). At D21, the presence and diameter of the corpus luteum (CL) were registered. AFC was highly repeatable, regardless of hormone induction in both G-N (r=0.79) and G-NA (r=0.90). The mean AFC was greater in G-N compared to G-NA (24.2±8.5 vs. 17.7±9.0 follicles). A variation in BCS throughout the study occurred in G-NA, but not in G-N. The average weight gain (AWG) was greater in G-NA compared to G-N (0.69±0.33 vs. 0.40±0.29kg/day). The G-NA resulted in a larger diameter of DF at D12 than G-N (11.6±2.7 vs. 9.3±1.5mm). In conclusion, AFC was greater in Nelore heifers, although in both breeds this count was highly repeatable during puberty induction. Crossbred heifers had greater BCS and AWG with greater diameter of DF, indicating higher precocity when compared to Nelore heifers.


Novilhas pré-púberes Nelore (G-N=15) e mestiças Nelore x Aberdeen Angus (G-NA=15) foram utilizadas neste estudo. CFA, peso vivo, escore de condição corporal (ECC), diâmetros do ovário e folículo dominante (FD) foram determinados em cada animal. A indução da puberdade foi realizada pela inserção de um dispositivo de progesterona de quarto uso (D0), que foi retirado no D12. Além disso, 1mg de benzoato de estradiol foi administrado e a intensidade do estro foi classificada (D12). No D21, foram registrados a presença e o diâmetro do corpo lúteo (CL). A CFA foi altamente repetível, independentemente da indução hormonal em G-N (r=0,79) e G-NA (r=0,90). A CFA média foi maior em G-N em comparação com G-NA (24,2±8,5 vs. 17,7±9,0 folículos). Uma variação no ECC ao longo do estudo ocorreu em G-NA, mas não em G-N. O ganho de peso médio (GPM) foi maior em G-NA em comparação com G-N (0,69±0,33 vs. 0,40±0,29kg/dia). O G-NA resultou em um diâmetro maior de FD em D12 do que o G-N (11,6±2,7 vs. 9,3±1,5mm). Em conclusão, a CFA foi maior em novilhas Nelore, embora em ambas as raças essa contagem tenha sido altamente repetível durante a indução da puberdade. Novilhas mestiças apresentaram maior ECC e GPM com maior diâmetro de FD, indicando maior precocidade quando comparadas às novilhas Nelore.


Asunto(s)
Animales , Bovinos , Bovinos/crecimiento & desarrollo , Pubertad , Grupos Raciales , Hormonas
6.
J Med Ultrasound ; 30(4): 282-286, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36844767

RESUMEN

Background: The purpose of the study was to compare three-dimensional (3D) ultrasound semiautomatic antral follicle count (AFC) with two-dimensional (2D) ultrasound real-time AFC to evaluate patients with deep endometriosis and/or endometrioma submitted to ovarian stimulation (OS). Methods: This was a retrospective cohort study assessing all women with documented diagnosis of deep endometriosis who underwent OS for assisted reproduction treatment. The primary outcome was the difference between AFC by semiautomatic 3D follicle count using 3D volume datasets and 2D ultrasound count with the number of oocytes retrieved at the end of the cycle. The 3D ultrasound AFC was obtained using sonography-based automated volume count (SonoAVC), and the 2D ultrasound AFC data was collected from the electronic medical record. Results: Total of 36 women had deep endometriosis documented by magnetic resonance imaging, laparoscopy, or ultrasonography and 3D ovarian volume datasets stored from their first exam. The differences between the 2D and 3D AFC and the number of oocytes retrieved at the end of the stimulation were compared, showing no significant statistical difference between both methods (P = 0.59). Correlations were similar using both methods when compared to the number of oocytes retrieved (2D [r = 0.83, confidence interval (CI) = 0.68-0.9, P < 0.001]); (3D [r = 0.81, CI = 0.46-0.83, P < 0.001]). Conclusion: 3D semiautomatic AFC can be used to access the ovarian reserve in patients with endometriosis.

7.
JBRA Assist Reprod ; 26(3): 387-397, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34786902

RESUMEN

OBJECTIVE: To understand which of the controlled ovarian stimulation (COS) protocols used in different patients are associated with greater amounts of oocytes retrieved. METHODS: The study population was divided into three groups, considering AMH and AFC to obtain the Ovarian Response Predictor Index (ORPI); they were grouped into: G1-Low Reserve (ORPI <0.5); G2-Normal Reserve (ORPI:0.5-0.9); and G3-High Reserve (ORPI≥0.9). 246 cycles were selected in which COS was used: recombinant FSH - follitropin alfa or beta (Protocol 1) or corifollitropin alfa (Protocol 2), both associated with urinary HMG and the GnRH antagonist, with the trigger performed using recombinant hCG or GnRH agonist. RESULTS: The number of oocytes obtained was higher in protocol 1 in all groups, with higher counts seen in G1 than in G2 or G3. The number of days required in COS for protocol 2 was greater than for protocol 1 in all groups. The total dose of recombinant FSH alfa or beta / urinary HMG used in protocol 1 was inversely proportional to the ovarian reserve. The lower the ORPI, the greater the average number of international units administered. In protocol 2, there was a need to supplement with higher doses of urinary HMG when compared to protocol 1. The dosage of the GnRH antagonist was dependent on the number of COS days until the trigger was used. In obtaining MII oocytes, the percentages were similar regardless of the trigger used. CONCLUSIONS: The use of follitropin leads to greater numbers of retrieved oocytes than corifollitropin alfa in all ORPIs. The dose of recombinant FSH used with urinary HMG increases inversely proportional to the ORPI value. The fixed dose of recombinant FSH deposit requires a sharp increase in the dose of urinary HMG.


Asunto(s)
Hormona Folículo Estimulante , Inducción de la Ovulación , Fertilización In Vitro/métodos , Hormona Folículo Estimulante/uso terapéutico , Hormona Liberadora de Gonadotropina , Antagonistas de Hormonas , Humanos , Oocitos , Inducción de la Ovulación/métodos , Técnicas Reproductivas Asistidas , Estudios Retrospectivos
8.
Semina ciênc. agrar ; 42(05): 2851-2866, set.-out. 2021. graf, tab
Artículo en Inglés | VETINDEX | ID: biblio-1501877

RESUMEN

This study used Holstein cattle to evaluate the following: I) the productive and reproductive characteristics of cows with low, intermediate and high antral follicle counts (AFCs) that were subjected to artificialin semination (AI) and comparison of AFC variability at the time of AI (nonpregnant) and at two time points during pregnancy (30 and 60 days), and II) whether the pregnancy status and different pregnancy periods in heifers improves the efficiency at in vitro embryo production (IVEP). In study I, 75 high-milk production cows with body condition scores (BCSs) of 2.75 to 4.75 and ages of 23 to 99 months were selected. Onthe day of estrus, AFCs (follicles ≥ 3 mm), BCS, body weight, and diameters of the dominant follicle, ovaries and the corpus luteum were evaluated. Posteriorly, AFC was monitored in pregnant cows at 30 days (n =35) and at 60 days for comparison of AFC before pregnancy versus different periods. In study II, heifers (n = 9) with BCS of 2.5 to 3.5 and ages of 10 to 16 months were selected for ovum pick-up and an IVEP program before AI (nonpregnant) as well as at 0 to 30, 31 to 60, and > 60 days of pregnancy. Statistical analysis was performed using PROC GLM and binary logistic regression model (P ≤ 0.05). In study I, AFC was not associated with variations in productive and reproductive parameters. However, AFCs in the low group increased following pregnancy (AI: 14.82 ± 1.36, 30 days: 23.45 ± 2.31 and 60 days: 35.18 ± 3.17 follicles). AFCs increased from AI to 60 days in the intermediate group but did not vary among time points in the high group. AFCs varied among AFC groups in AI and at 30 days of pregnancy but not at 60 days. In study II, the mean of total oocytes (17.43 ± 4.52 vs. 41.67 ± 3.79) and viable oocytes (13.77 ± 3.63 vs. 30.56± 3.45) increased from AI (nonpregnant) to the first 30 days of pregnancy. [...]


Este estudo utilizou fêmeas da raça Holandesa para avaliar: i) variação da contagem de folículos antrais na gestação; ii) resultado da produção in vitro de embriões em doadoras antes e depois da gestação. No estudo I, 75 vacas de alta produção de leite com escores de condição corporal (ECC) de 2,75 a 4,75 e idades de 23 a 99 meses foram selecionadas. No dia do estro a CFA foi avaliada (folículos ≥ 3 mm) além do escore corporal, peso corporal e diâmetros do folículo dominante, ovários e corpo lúteo. Posteriormente, a CFA foi monitorada nas vacas gestantes (n = 35) aos 30 e 60 dias. No estudo II, novilhas (n = 9) com ECC de 2,5 a 3,5 e idades de 10 a 16 meses foram selecionadas para obtenção de oócitos antes e depois da gestação, no primeiro, segundo e acima dos dois meses de gestação. A análise estatística foi realizada usando PROC GLM e modelo de regressão logística binária (P ≤ 0,05). No estudo I, a CFA não foi associada a variações nos parâmetros produtivos e reprodutivos. No entanto, as vacas de baixa CFA apresentaram aumento no número de folículos após início da gestação (IA: 14,82 ± 1,36, 30 dias: 23,45 ± 2,31 e 60 dias:35,18 ± 3,17 folículos). A CFA aumentou da IA para 60 dias no grupo de CFA intermediária, mas não variou ao longo do tempo no grupo de alta CFA. A CFA variou entre os grupos comparando-se o momento da IA e 30 dias de gestação. No estudo II, entre a IA e o primeiro mês de gestação, houve aumento do total de oócitos (17,43 ± 4,52 vs. 41,67 ± 3,79), bem como de oócitos viáveis (13,77 ± 3,63 vs. 30,56 ± 3,45). O número médio de embriões produzidos aumentou durante a gestação, [...]


Asunto(s)
Femenino , Animales , Bovinos , Fertilidad/genética , Preñez/genética , Técnicas de Cultivo de Embriones/veterinaria
9.
Semina Ci. agr. ; 42(05): 2851-2866, set.-out. 2021. graf, tab
Artículo en Inglés | VETINDEX | ID: vti-31814

RESUMEN

This study used Holstein cattle to evaluate the following: I) the productive and reproductive characteristics of cows with low, intermediate and high antral follicle counts (AFCs) that were subjected to artificialin semination (AI) and comparison of AFC variability at the time of AI (nonpregnant) and at two time points during pregnancy (30 and 60 days), and II) whether the pregnancy status and different pregnancy periods in heifers improves the efficiency at in vitro embryo production (IVEP). In study I, 75 high-milk production cows with body condition scores (BCSs) of 2.75 to 4.75 and ages of 23 to 99 months were selected. Onthe day of estrus, AFCs (follicles ≥ 3 mm), BCS, body weight, and diameters of the dominant follicle, ovaries and the corpus luteum were evaluated. Posteriorly, AFC was monitored in pregnant cows at 30 days (n =35) and at 60 days for comparison of AFC before pregnancy versus different periods. In study II, heifers (n = 9) with BCS of 2.5 to 3.5 and ages of 10 to 16 months were selected for ovum pick-up and an IVEP program before AI (nonpregnant) as well as at 0 to 30, 31 to 60, and > 60 days of pregnancy. Statistical analysis was performed using PROC GLM and binary logistic regression model (P ≤ 0.05). In study I, AFC was not associated with variations in productive and reproductive parameters. However, AFCs in the low group increased following pregnancy (AI: 14.82 ± 1.36, 30 days: 23.45 ± 2.31 and 60 days: 35.18 ± 3.17 follicles). AFCs increased from AI to 60 days in the intermediate group but did not vary among time points in the high group. AFCs varied among AFC groups in AI and at 30 days of pregnancy but not at 60 days. In study II, the mean of total oocytes (17.43 ± 4.52 vs. 41.67 ± 3.79) and viable oocytes (13.77 ± 3.63 vs. 30.56± 3.45) increased from AI (nonpregnant) to the first 30 days of pregnancy. [...](AU)


Este estudo utilizou fêmeas da raça Holandesa para avaliar: i) variação da contagem de folículos antrais na gestação; ii) resultado da produção in vitro de embriões em doadoras antes e depois da gestação. No estudo I, 75 vacas de alta produção de leite com escores de condição corporal (ECC) de 2,75 a 4,75 e idades de 23 a 99 meses foram selecionadas. No dia do estro a CFA foi avaliada (folículos ≥ 3 mm) além do escore corporal, peso corporal e diâmetros do folículo dominante, ovários e corpo lúteo. Posteriormente, a CFA foi monitorada nas vacas gestantes (n = 35) aos 30 e 60 dias. No estudo II, novilhas (n = 9) com ECC de 2,5 a 3,5 e idades de 10 a 16 meses foram selecionadas para obtenção de oócitos antes e depois da gestação, no primeiro, segundo e acima dos dois meses de gestação. A análise estatística foi realizada usando PROC GLM e modelo de regressão logística binária (P ≤ 0,05). No estudo I, a CFA não foi associada a variações nos parâmetros produtivos e reprodutivos. No entanto, as vacas de baixa CFA apresentaram aumento no número de folículos após início da gestação (IA: 14,82 ± 1,36, 30 dias: 23,45 ± 2,31 e 60 dias:35,18 ± 3,17 folículos). A CFA aumentou da IA para 60 dias no grupo de CFA intermediária, mas não variou ao longo do tempo no grupo de alta CFA. A CFA variou entre os grupos comparando-se o momento da IA e 30 dias de gestação. No estudo II, entre a IA e o primeiro mês de gestação, houve aumento do total de oócitos (17,43 ± 4,52 vs. 41,67 ± 3,79), bem como de oócitos viáveis (13,77 ± 3,63 vs. 30,56 ± 3,45). O número médio de embriões produzidos aumentou durante a gestação, [...](AU)


Asunto(s)
Animales , Femenino , Bovinos , Preñez/genética , Fertilidad/genética , Técnicas de Cultivo de Embriones/veterinaria
10.
Hum Reprod ; 36(6): 1530-1541, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-33822057

RESUMEN

STUDY QUESTION: What is the agreement between antral follicle count (AFC) and anti-Müllerian hormone (AMH) levels when used to patient classification according to the Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria? SUMMARY ANSWER: Our study indicates a strong agreement between the AFC and the AMH levels in classifying POSEIDON patients; thus, either can be used for this purpose, although one in four women will have discordant values when both biomarkers are used. WHAT IS KNOWN ALREADY: According to the POSEIDON criteria, both AFC and AMH may be used to classify low-prognosis patients. Proposed AFC and AMH thresholds of 5 and 1.2 ng/ml, respectively, have their basis in published literature; however, no study has yet determined the reproducibility of patient classification in comparing one biomarker with the other, nor have their thresholds ever been validated within this patient population. STUDY DESIGN, SIZE, DURATION: A population-based cohort study involving 9484 consecutive patients treated in three fertility clinics in Brazil, Turkey and Vietnam between 2015 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were infertile women between 22 and 46 years old in their first in vitro fertilization/intracytoplasmic sperm injection cycle of standard ovarian stimulation with exogenous gonadotropins whose baseline ovarian reserves had been assessed by both AFC and AMH. Details of pre- and post-treatment findings were input into a coded research file. Two indicators of interest were created to classify patients according to the POSEIDON criteria based upon AFC and AMH values. Patients who did not fit any of the four POSEIDON groups were classified as non-POSEIDON. AFC was determined in the early follicular phase using two-dimensional (2D) transvaginal ultrasonography, whereas AMH values were based on the modified Beckman Coulter generation II enzyme-linked immunosorbent assay. Agreement rates were computed between AFC and AMH to classify patients using Cohen's kappa statistics. Logistic regression analyzes were carried out to examine the association between ovarian markers and low (<4) and suboptimal (4-9) oocyte yield. MAIN RESULTS AND THE ROLE OF CHANCE: The degree of agreement in classifying patients according to POSEIDON groups was strong overall (kappa = 0.802; 95% CI: 0.792-0.811). A total of 73.8% of individuals were classified under the same group using both biomarkers. The disagreement rates were ∼26% and did not diverge when AFC or AMH was used as the primary biomarker criterion. Significant regression equations were found between ovarian markers and oocyte yield (P < 0.0001). For low oocyte yield, the optimal AFC and AMH cutoff values were 5 and 1.27 ng/ml with sensitivities of 0.61 and 0.66, specificities of 0.81 and 0.72, and AUC receiver operating characteristics of 0.791 and 0.751, respectively. For suboptimal oocyte yield respective AFC and AMH cutoffs were 12 and 2.97 ng/ml with sensitivities of 0.74 and 0.69, specificities of 0.76 and 0.66 and AUCs of 0.81 and 0.80. LIMITATIONS, REASONS FOR CAUTION: Our study relied on 2D transvaginal sonography to quantify the AFC and manual Gen II assay for AMH determination and classification of patients. AMH data must be interpreted in an assay-specific manner. Treatment protocols varied across centers potentially affecting patient classification. WIDER IMPLICATIONS OF THE FINDINGS: Three of four patients will be classified the same using either AFC or AMH values. Both biomarkers provide acceptable and equivalent accuracy in predicting oocyte yield further supporting their use and proposed thresholds in daily clinical practice for patient classification according to the POSEIDON criteria. However, the sensitivity of POSEIDON thresholds in predicting low oocyte yield is low. Clinicians should adopt the biomarker that may best reflect their clinical setting. STUDY FUNDING/COMPETING INTEREST(S): Unrestricted investigator-sponsored study grant (MS200059_0013) from Merck KGaA, Darmstadt, Germany. The funder had no role in study design, data collection, analysis, decision to publish or manuscript preparation. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. H.Y. declares receipt of payment for lectures from Merck and Ferring. L.N.V. receives speaker fees and conferences from Merck, Merck Sharp and Dohme (MSD) and Ferring and research grants from MSD and Ferring. T.M.H. received speaker fees and conferences from Merck, MSD and Ferring. The remaining authors have nothing to disclose. TRIAL REGISTRATION NUMBER: not applicable.


Asunto(s)
Hormona Antimülleriana , Infertilidad Femenina , Adulto , Brasil , Estudios de Cohortes , Femenino , Alemania , Humanos , Infertilidad Femenina/diagnóstico , Persona de Mediana Edad , Oocitos , Inducción de la Ovulación , Pronóstico , Reproducibilidad de los Resultados , Turquía , Vietnam , Adulto Joven
11.
JBRA Assist Reprod ; 25(1): 109-114, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-32960526

RESUMEN

OBJECTIVE: The aim of the present prospective study was to evaluate which ovarian reserve marker would be more reliable as the quality of the A + B embryos (day 3 and blastocyst). METHODS: We ran a prospective study with 124 infertile women, aged 24-48 years, from 2017 to 2018. The patients were divided into 3 groups according to age and the subgroups were compared for AMH, AFC, number of A+B embryos. New division of the 3 groups was performed based on the AMH, and the subgroups were compared for age, AFC and number of A+B embryos. Finally, we divided the patients into 3 groups, based on the AFC, and we compared the subgroups for age, AMH and number of A+B embryos. P<0.05 was considered statistically significant. RESULTS: When the 124 patients were divided according to age, we found a significant fall in an A+B embryo quality (day3; blastocyst) after 35 years (p<0.038; p<0.035), and more severely after 37 years (p<0.032; p<0.027). When the 124 patients were divided according to AMH, there was a significant fall in A+B embryo quality (day 3; blastocyst), with AMH<1ng/ml (p<0.023; p<0.021). When the 124 patients were divided according to AFC, there was a significant fall in A+B embryo quality (day 3; blastocyst) with AFC<7 (p<0.025; p<0.023). These markers had significant associations with embryo quality (p<0.005). CONCLUSION: Age, AFC and AMH have significant associations with A +B embryo quality on day 3 and blastocyst.


Asunto(s)
Infertilidad Femenina , Reserva Ovárica , Adulto , Hormona Antimülleriana , Blastocisto , Femenino , Humanos , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/epidemiología , Folículo Ovárico , Estudios Prospectivos
12.
Rev. bras. reprod. anim ; 45(4): 202-209, out.-dez. 2021. ilus, graf
Artículo en Portugués | VETINDEX | ID: biblio-1492661

RESUMEN

A implementação das biotécnicas reprodutivas juntamente com os programas de melhoramento genético tem contribuído expressivamente para uma rápida disseminação de indivíduos melhoradores, tanto pelo uso da inseminação artificial, quanto pela produção in vivo e in vitro de embriões. No entanto, a eficiência destes programas está condicionada a uma série de fatores que podem afetar de maneira significativa a performance reprodutiva tanto em bovinos de corte, como de leite. Neste contexto, a contagem de folículos antrais (CFA) se destaca como um dos fatores de maior influência e ainda pouco compreendido. Empregando a ultrassonografia, fêmeas podem ser classificada em baixa, intermediária ou alta CFA, devido à alta variabilidade desta contagem no rebanho. Além disso, a alta repetibilidade desta característica possibilita realizar esta classificação em diferentes momentos da vida reprodutiva da fêmea. De maneira geral, doadoras de alta CFA tem proporcionado maiores rendimentos embrionários tanto na técnica in vivo quanto in vitro. Entretanto, fêmeas de baixa CFA têm apresentado maiores diâmetros foliculares e maior taxa de prenhez quando submetidas à IATF. Embora a CFA atue como um fator de grande influência, sua herdabilidade é baixa e não há relação com características zootécnicas de programas de melhoramento. Finalmente, a CFA tem se destacado como uma importante ferramenta de seleção de matrizes e que tem contribuído significativamente para um maior sucesso nos programas reprodutivos.


The implementation of reproductive biotechniques and genetic improvement programs has significantly contributed to a fast dissemination of animals with high genetic, both by artificial insemination and in vivo and in vitro embryo production. However, the efficiency of these programs is conditioned to several factors that can considerably affect the reproductive performance in both beef and dairy cattle. In this context, the antral follicle count (AFC) stands out as one of the most influential and still poorly understood factors. Females can be classified as low, intermediate, or high AFC by ultrasonography due to the high variability of this count in the herd. In addition, the high repeatability of this characteristic allows high confidence in carrying out this classification at different times of the reproductive life. In general, high AFC donors have provided higher embryo yields both in vivo and in vitro. However, females with low AFC have shown larger follicular diameters and higher pregnancy rate when submitted to TAI. Although AFC is a factor of great influence, its heritability is low and there is no relationship with zootechnical characteristics of breeding programs. Finally, AFC has emerged as an important tool to female’s selection and has significantly contributed to greater success in breeding programs.


Asunto(s)
Femenino , Animales , Bovinos , Fertilidad , Folículo Ovárico , Inseminación Artificial
13.
Anim Reprod Sci ; 221: 106601, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32961391

RESUMEN

In the present study, there was an evaluation of in vitro embryo production (IVEP) in Bos indicus donor cows with small or large antral follicle counts (AFCs) when there was synchronization of follicular dynamics among cows before ovum pick-up (OPU). Donor cows classified as having small or large AFC were submitted to OPU/IVEP program (Experiment-I) or had follicular-stage synchronization imposed before OPU/IVEP (Experiment-II). In Experiment-I, the cows with a large AFC had a greater (P < 0.01) mean of embryos developing to the blastocyst stage compared to those with a small AFC. In Experiment-II, percentage of viable oocytes/OPU were not affected (P = 0.33) by synchronization of follicular dynamics, but the AFC had an effect (P < 0.0001). There was an interaction (P = 0.01) indicating the larger AFC, with or without imposing of a synchronization treatment regimen, resulted in the most desirable outcome. The number of embryos was affected (P < 0.001) by follicular-stage synchronization and AFC, with there being an interaction (P = 0.002) with the most desirable results for the large AFC-synchronized group. Number of pregnancies was greater (P ≤ 0.02) for recipient females with embryos from synchronized donors and with a large AFC. There was an interaction (P = 0.03) with there being a greater pregnancy percentage for cows with synchronized follicular stages and the large AFC. Bos indicus donor with a large AFC when associated with the synchronization of stage of follicular dynamics pre-OPU results in improvement of the efficacy of IVEP.


Asunto(s)
Bovinos/embriología , Sincronización del Estro , Folículo Ovárico/fisiología , Óvulo/fisiología , Recolección de Tejidos y Órganos/veterinaria , Animales , Bovinos/fisiología , Transferencia de Embrión , Femenino , Embarazo
14.
J Ovarian Res ; 13(1): 94, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807228

RESUMEN

BACKGROUND: To determine if a modified ovarian sensitivity index (MOSI), based on initial follicular measurements and the initial follicle-stimulating hormone (FSH) dose, can predict the production of high-quality embryos for successful implantation during in vitro fertilization (IVF). METHODS: This study consisted of two phases: 1) a retrospective study and 2) a prospective observational study. For the first phase, 363 patients charts were reviewed, of which 283 had embryos transferred. All women underwent a standardized antagonist-based IVF protocol. At the first follow-up (Day 3/4), the number and size of the follicles were determined. MOSI was calculated as ln (number follicles (≥6 mm) × 1000 / FSH initial dose). Afterward, the number and quality of the ova, embryo development, and the number and quality of the blastocysts were determined. Embryo implantation was confirmed by ß-hCG. For the second phase, 337 IVF cycles were followed to determine MOSI's accuracy. RESULTS: MOSI could predict the production of ≥4 high-quality embryos by Day 2 (AUC = 0.69, 95%CI:0.63-0.75), ≥2 blastocysts (AUC = 0.74, 95%CI:0.68-0.79), and ≥ 35% rate of blastocyst formation (AUC = 0.65, 95%CI:0.58-0.72). Using linear regression, MOSI was highly associated with the number of ova captured (ß = 5.15), MII oocytes (ß = 4.31), embryos produced (ß = 2.90), high-quality embryos (ß = 0.98), and the blastocyst formation rate (ß = 0.06, p < 0.01). Using logistic regression, MOSI was highly associated with achieving ≥4 high-quality embryos (odds ratio = 2.80, 95%CI:1.90-4.13), ≥2 blastocysts (odds ratio = 3.40, 95%CI:2.33-4.95), and ≥ 35% blastocysts formation rate (odds ratio = 1.96, 95%CI:1.31-2.92). This effect was independent of age, BMI, and antral follicle count. For implantation, MOSI was significantly associated with successful implantation (odds ratio = 1.79, 95%CI:1.25-2.57). For the prospective study, MOSI was highly accurate at predicting ≥6 high-quality embryos on Day 2 (accuracy = 68.5%), ≥6 blastocysts (accuracy = 68.0%), and a blastocyst formation rate of ≥35% (accuracy = 61.4%). CONCLUSION: MOSI was highly correlated with key IVF parameters that are associated with achieved pregnancy. Using this index with antagonist cycles, clinicians may opt to stop an IVF cycle, under the assumption that the cycle will fail to produce good blastocysts, preventing wasting the patient's resources and time.


Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Ovario/fisiología , Inducción de la Ovulación/métodos , Adulto , Implantación del Embrión , Femenino , Fertilización In Vitro , Humanos , Ovario/efectos de los fármacos , Embarazo , Índice de Embarazo , Estudios Prospectivos , Estudios Retrospectivos , Adulto Joven
15.
Rev. MED ; 28(1): 77-88, ene.-jun. 2020.
Artículo en Español | LILACS | ID: biblio-1143834

RESUMEN

Resumen: La necesidad de investigar la reserva ovárica para apoyar la consejería acerca del éxito o fracaso de los tratamientos de reproducción asistida, principalmente en pacientes con riesgo de falla reproductiva, ha generado la descripción y el uso de pruebas histológicas, basales, dinámicas y ultrasonográficas. La presente revisión tiene como objetivo describir y analizar las diferentes pruebas de evaluación de la reserva ovárica, sus limitaciones y ventajas, y ampliar la información referente a las que, por sus características y resultados, son más utilizadas en la actualidad. Para cumplirlo se realizó búsqueda en bases de datos, incluyendo investigaciones originales, revisiones sistemáticas, metaanálisis, reportes de casos y consensos de expertos, en inglés y español, desde 1980. En cuanto a los resultados, puede decirse que pruebas como la biopsia ovárica, medición de Inhibina B, test de estímulo con FSH o con GnRH, y con citrato de clomifeno, han caído en desuso; la medición de la FSH, si bien todavía utilizada, claramente tiene menor capacidad predictiva que el Conteo de Folículos Antrales (CFA) y la Hormona Antimülleriana (HAM). Se concluye que el CFA y la medición de ham son las pruebas más recomendadas, con mejor capacidad predictiva y que, no obstante algunas limitaciones, permiten un acercamiento a la estimación de la respuesta al estímulo ovulatorio. Se plantean opciones para el futuro que permitirán, a mediano plazo, resolver los interrogantes sobre la "verdadera" reserva ovárica.


Abstract: The need to investigate the ovarian reserve to support counseling about the success or failure of assisted reproduction systems has generated the description and use of histological, basal, dynamic, and ultrasound text. The purpose of this review is to describe and analyze the different tests for evaluating ovarian reserve, their limitations and advantages, and to expand the information regarding those that, due to their characteristics and results, are most widely used today. To achieve this, databases searches were carried out, including for original research, systematic reviews, meta-nalyses, case reports and expert consensus, in English and Spanish, since 1980. Regarding the results, it can be said that tests such as ovarian biopsy, measurement of Inhibin B, FSH or GnRH stimulation test, and with clomiphene citrate, have fallen into disuse. FSH measurement, although still used, clearly has a lower predictive capacity than the Antral Follicle Count (AFC) and the Antimullerian Hormone (AMH). It is concluded that the AFC and the AMH measurement are the most recommended tests, with better predictive capacity and that, despite some limitations, they allow closer estimation of the response to ovulatory stimulus. Options for the future that will allow solving the questions in the medium term about the "true" ovarian reserve are proposed.


Resumo: A necessidade de pesquisar sobre a reserva ovariana para apoiar o aconselhamento acerca do sucesso ou do fracasso dos tratamentos de reprodução assistida, principalmente em pacientes com risco de falha reprodutiva, vem gerando a descrição e o uso de exames histológicos, basais, dinâmicos e ultrassonográficos. Esta revisão tem o objetivo de descrever e analisar os diferentes exames de avaliação da reserva ovariana, suas limitações e vantagens, e ampliar a informação referente aos que, por suas características e resultados, são mais utilizados na atualidade. Para isso, foi realizada busca em base de dados, que incluiu pesquisas originais, revisões sistemáticas, meta-aná-lise, relatos de caso e consenso de especialistas, em inglês e em espanhol, desde 1980. Quanto aos resultados, pode-se dizer que os exames como biópsia ovariana, a medição de Inibina B, exame de estímulo com FSH ou com GnRH, e com citrato de clomifeno estão em desuso; a medição da FSH, embora ainda utilizada, claramente tem menor capacidade preditiva que a contagem de folículos antrais (CFA) e o hormônio antimulleriano (HAM). Conclui-se que o CFA e a medição do HAM são os exames mais recomendados, com melhor capacidade preditiva e que, apesar de algumas limitações, permitem uma aproximação da estimativa da resposta ao estímulo da ovulação. São apresentadas opções para o futuro que possibilitarão, em médio prazo, resolver as questões sobre a "verdadeira" reserva ovariana.


Asunto(s)
Humanos , Femenino , Adolescente , Adulto , Reserva Ovárica , Consejo , Número Básico de Reproducción , Hormona Antimülleriana
16.
Anim Reprod Sci ; 217: 106357, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32408964

RESUMEN

It was hypothesized that Brahman cows have greater in vitro embryo production than Simmental cows, and that regardless of breed, antral follicle count (AFC) and vulvar width (VW) are positively associated with oocyte quality, embryo number and pregnancy rate. Brahman (Bos taurus indicus, n = 184) and Simmental (Bos taurus taurus, n = 99) cows were classified as having a large AFC (Brahman: ≥50, Simmental: ≥25); intermediate AFC (Brahman: >30 and ≤49; Simmental: >16 and <24) and small AFC (Brahman: <30, Simmental: ≤15). The VW was considered to be large (Brahman: >123 mm, Simmental: >80 mm); intermediate (Brahman: >102 mm and ≤123 mm; Simmental: >65 mm and ≤80 mm) and small (Brahman: ≤102 mm and Simmental: ≤65 mm). For each group of cows, ovum pick up, oocyte in vitro maturation, fertilization and embryo culture were performed. Embryo transfers were subsequently performed and pregnancy rate was evaluated. Brahman cows had a larger number of viable oocytes, greater efficiency of embryo production and greater pregnancy rate (P < 0.05) than Simmental cows. Pregnancy percentages in Simmental cows with a small AFC were greater than those cows with an intermediate and large AFC. With the Brahman cows, there was no difference in pregnancy rate among the cows with different AFC classifications. In contrast to Simmental cows, Brahman cows with an intermediate VW had a greater pregnancy percentage than those with a small and large AFC. In conclusion, Brahman cows have a larger AFC, number of viable oocytes, and pregnancy rate than Simmental cows.


Asunto(s)
Bovinos/clasificación , Técnicas de Cultivo de Embriones/veterinaria , Oocitos/fisiología , Folículo Ovárico/citología , Vulva/anatomía & histología , Animales , Bovinos/fisiología , Transferencia de Embrión/veterinaria , Femenino , Embarazo , Índice de Embarazo , Recolección de Tejidos y Órganos , Vitamina E/análogos & derivados
17.
JBRA Assist Reprod ; 23(4): 402-407, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-31361435

RESUMEN

OBJECTIVES: To find a pretreatment predictor for achieving a live birth. Assisted reproduction technology with IVF/ICSI is the ultimate chance for some couples to conceive a child. The expectations are high and it is important to give them a realistic perspective about the chances of achieving a live birth. METHODS: A retrospective cohort study of all IVF/ICSI cycles performed in our center between 2012 and 2016. We considered only those cycles with a live birth delivery after 24 weeks, or cycles with no surplus embryos left. The following data was evaluated: AMH; AFC; age; BMI; previous diagnosis; type of treatment; number of previous deliveries; ethnicity, smoking status. Univariate and multivariate analysis were used to examine the association of live birth with baseline patient characteristics. We determined the odds-ratio for all the statistically significant variables (p<0.05), in a multivariate model. The results are presented according to the predictors founded. RESULTS: 739 cycles were evaluated: 9.1% were canceled; 10.2% did not have oocytes; 15.6% did not have D2 embryos; 31.4% achieved a live birth. The univariate analysis revealed statistically significant differences regarding AMH, AFC and women's age between couples with and without a live birth (p<0.001), and the cause of infertility. We found no association with live births in other variables. These variables were categorized and used in a multivariate analysis. CONCLUSION: Age, AMH, AFC and cause, when sub-classified, are independently associated with the results of an IVF/ICSI treatment. These results enable couples to face real expectations in their particular scenario.


Asunto(s)
Tasa de Natalidad , Fertilización In Vitro , Infertilidad/terapia , Nacimiento Vivo , Inyecciones de Esperma Intracitoplasmáticas , Adolescente , Adulto , Femenino , Humanos , Recién Nacido , Masculino , Folículo Ovárico , Inducción de la Ovulación/métodos , Paridad , Embarazo , Índice de Embarazo , Pronóstico , Estudios Retrospectivos , Adulto Joven
18.
Theriogenology ; 136: 10-14, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31234052

RESUMEN

An experiment was performed to evaluate the association between the antral follicle count (AFC) plus body condition score (BCS) and the pregnancy rate in Bos indicus undergoing timed artificial insemination (TAI). A total of 736 Nelore cows with BCSs ranging from 2 to 4 received a conventional protocol for TAI. On a random day of the estrous cycle (Day 0), all cows received an intravaginal P4 device and an intramuscular (i.m.) injection of 2.0 mg estradiol benzoate. On Day 8, the P4 device was removed, and 150 µg sodium D-cloprostenol, 300 IU equine chorionic gonadotrophin and 1.0 mg estradiol cypionate were administered by i.m. injection. TAI was performed 48 h after P4 device removal, and pregnancy diagnosis was performed by ultrasonography after 30 days. On Day 0, all cows were examined by ultrasonography to determine the AFC by counting the number of follicles >3 mm in diameter that were present in both ovaries and to evaluate the BCS (scale of 1-5). The cows were then classified based on their AFCs as those with low (≤10 follicles), intermediate (11-29 follicles) and high AFC (≥30 follicles). Furthermore, cows were classified as having low (≥2.0 to ≤ 2.9) and high (≥3.0 to ≤ 4.0) BCSs. The AFCs and BCSs were analyzed using the generalized linear model, and the pregnancy rate was assessed with the binary logistic regression model (P ≤ 0.05). The pregnancy rate was influenced (P < 0.05) by AFC and BCS classification and by interactions (P = 0.034) between these factors. Cows with a low AFC exhibited higher a pregnancy rate than did cows with a high or an intermediate AFC (57.7% a, 47.9% b and 49.7% b, P = 0.008). Low BCS resulted in a higher pregnancy rate than did high BCS (55.2% vs. 50.4%, P = 0.008). Cows with a high BCS and a low AFC had a higher pregnancy rate (P < 0.05) than did those with a high BCS and an intermediate or a high AFC (59.8%a, 48.0%b, and 38.0%b, respectively). An interaction (P < 0.05) was observed between the AFC and BCS, and the pregnancy rate decreased significantly in cows with an AFC > 30 and a BCS between 3 and 4. In conclusion, AFC and BCS classifications influence the pregnancy rate of Bos indicus beef cattle subjected to TAI. In addition, an important interaction between these factors was observed, namely, the lowest pregnancy rates were found in cows with high BCSs and high AFCs.


Asunto(s)
Composición Corporal/fisiología , Inseminación Artificial/veterinaria , Folículo Ovárico/fisiología , Índice de Embarazo , Animales , Bovinos , Femenino , Embarazo
19.
JBRA Assist Reprod ; 23(4): 414-417, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-31251010

RESUMEN

One in six couples worldwide will experience at least one infertility problem during their reproductive years. Between 5.6% and 35.1% of women will exhibit poor ovarian response. A variety of methods have been applied to improve ovarian response, including dehydroepiandrosterone. In the ovaries, dehydroepiandrosterone promotes follicular development and granulosa cell proliferation by increasing intraovarian androgen concentrations while simultaneously enhancing the level of follicular insulin-like growth factor-1, which promotes folliculogenesis. Dehydroepiandrosterone supplementation may improve in vitro fertilization outcomes and ovarian response in patients with poor ovarian response. However, a few questions still loom over the effectiveness of dehydroepiandrosterone.


Asunto(s)
Deshidroepiandrosterona/administración & dosificación , Fertilización In Vitro/métodos , Infertilidad Femenina/terapia , Inducción de la Ovulación/métodos , Adulto , Femenino , Humanos , Embarazo , Índice de Embarazo , Resultado del Tratamiento
20.
Rev. bras. reprod. anim ; 43(1): 13-17, jan.-mar. 2019.
Artículo en Portugués | VETINDEX | ID: biblio-1492542

RESUMEN

A produção in vitro de embriões (PIVE) é uma biotécnica que se consolidou nos últimos anos e seu uso em bovinos continua a expandir-se, especialmente no Brasil. A facilidade em obter oócitos e as características do rebanho brasileiro foram determinantes para este crescimento. É conhecido que animais Bos taurus indicus e Bos taurus taurus possuem diferenças fisiológicas, metabólicas, endócrinas e comportamentais que impactam diretamente a reprodução. Além disso, a contagem de folículos antrais (CFA) é um parâmetro conhecidamente repetível no indivíduo, mas seu impacto na reprodução das fêmeas ainda não está completamente elucidado, especialmente considerando suas interações com a subespécie. O objetivo da presente revisão é destacar os mecanismos pelos quais estas características influenciam o rendimento e aplicabilidade da produção in vitro de embriões bovinos.


In vitro embryo production (IVP) is a well stablished biotechnic, and its use in bovines is still expanding, especially in Brazil. The facility to obtain oocytes associated to the breed characteristics of the Brazilian herd were decisive for this expansion. It is known that the physiology, metabolism, endocrinal system and behavior are different for Bos taurus indicus and Bos taurus taurus animals, and these differences may impact directly on the characteristics of reproduction of these animals. Furthermore, the antral follicle count (AFC) is known to present high repeatability on the same female, but its impact on the female reproduction remains unclear, either in the interaction between AFC and subspecies. The aim of this review is to highlight the mechanisms through which the AFC and subspecies may influence the income and feasibility of bovine in vitro embryo production.


Asunto(s)
Femenino , Animales , Bovinos , Bovinos/embriología , Bovinos/fisiología , Folículo Ovárico , Técnicas de Cultivo de Embriones/clasificación , Técnicas de Cultivo de Embriones/veterinaria
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