RESUMO
Two experiments were conducted to evaluate the effect of different ovulation inducers on E-17ß plasma concentrations, synchronized ovulations and pregnancy rates. In Experiment 1, cows received a progesterone intravaginal device (PID) with 1 g of progesterone (P4) plus 2 mg of estradiol benzoate (EB) (day 0). At PID removal (day 8), cows received 0.150 mg of D-cloprostenol and were randomly assigned to four treatment groups (n = 10/treatment): Group ECP: 1 mg of estradiol cypionate at PID removal, Group EB: 1 mg of EB 24 hr after PID removal, Group GnRH: 10 µg of GnRH 48 hr after PID removal, Group ECP-GnRH: 1 mg of ECP at PID removal plus 10 µg of GnRH 48 hr later. Ultrasonographic examinations were performed to detect the dominant follicle and ovulation. GnRH-treated cows ovulated later (p < .05) compared to ECP- and ECP+GnRH-treated cows. There were effects of treatment, time and their interaction on E-17ß concentrations (p < .05). ECP treatment affected plasma E-17ß concentration, which increased earlier and decreased later compared to treatments without ECP. In Experiment 2, cows received (i) ECP: n = 126; (ii) EB: n = 126; (iii) GnRH: n = 136; (iv) ECP+GnRH: n = 139; FTAI was performed 48-50 hr after PID removal. Pregnancy rates did not differ among ovulation inducers (p > .05; ECP: 54.0%, 68/126; EB: 49.2%, 62/126; GnRH: 40.4%, 55/136; ECP+GnRH: 43.9%, 61/139). In conclusion, ECP administration (ECP and ECP+GnRH treatments) affected E-17ß concentrations, determining its earlier increase and later decrease compared to treatments without ECP (EB and GnRH treatments). ECP+GnRH-treated cows achieved the best distribution of ovulations without affecting pregnancy rates.
Assuntos
Bovinos , Estradiol/sangue , Estradiol/farmacologia , Sincronização do Estro/métodos , Hormônio Liberador de Gonadotropina/farmacologia , Ovulação/efeitos dos fármacos , Animais , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/farmacologia , Estradiol/administração & dosagem , Feminino , Lactação , Gravidez , Taxa de GravidezRESUMO
This study was designed to evaluate in suckling early pregnant beef cows with and without eCG-pre-stimulation: (i) the influence of day gestation (from 40 to 101 days) and the consecutive eCG treatments on the follicular growth induced by means of ultrasound-guided transvaginal follicle ablation (FA; all follicles ≥ 5 mm) and the number and quality oocytes recovered by ovum pick-up (OPU) and (ii) the possible effects of repeated hormonal stimulation and FA/OPU on pregnancy outcome. Twelve suckling early pregnant Angus cows (40 days post fixed-time artificial insemination) were randomly assigned to each of two groups (n=6 group(-1)). Group 1 treatments included: FA (Day 0), eCG (1600 IU; Day 1) and OPU (Day 5). Group 2: as cited Group 1 with no eCG treatment. In both groups, OPU was repeated five times (Days 45, 59, 73, 87 and 101 of gestation). The numbers (mean ± SEM) of class II (5-9 mm; 4.3 ± 0.9) and class III (≥10 mm; 2.5 ± 0.4) follicles visualized per cow per OPU session in eCG-treated cows were greater (P<0.05) than for non-treated cows (0.9 ± 0.1 and 0.9 ± 0.1, respectively). In contrast, the number (mean ± SEM) of class I (<5mm) follicles per cow per OPU session was lower for cows with eCG treatment (2.8 ± 0.4) than for non-treated cows (5.7 ± 0.5). The mean number of aspirated follicles was not significantly different (P<0.05) between eCG-treated cows and non-treated cows at 45 and 59 days of pregnancy. However, the mean number of aspirated follicles was greater (P=0.03) in eCG-treated cows than non-treated cows from 73 day of pregnancy onwards. The numbers (mean ± SEM) of recovered oocytes and viable oocytes/cow/session were greater (P<0.05) for eCG-treated cows (2.2 ± 0.2 and 1.6 ± 0.4, respectively) than for non-treated cows (1.0 ± 0.2 and 0.9 ± 0.2, respectively). No donor pregnancies were lost either during or following OPU procedure. We can conclude that (1) eCG-treated pregnant suckled cows can be a source of oocytes for IVF at least to 100 days of gestation and (2) repeated FA/eCG treatment/OPU procedures did not affect the pregnancy outcome.
Assuntos
Gonadotropinas Equinas/farmacologia , Recuperação de Oócitos , Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Prenhez , Animais , Animais Lactentes , Bovinos , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/farmacologia , Esquema de Medicação , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Fármacos para a Fertilidade Feminina/farmacologia , Idade Gestacional , Gonadotropinas Equinas/administração & dosagem , Recuperação de Oócitos/métodos , Oócitos/fisiologia , Ovário/fisiologia , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Óvulo/efeitos dos fármacos , Gravidez , Prenhez/efeitos dos fármacosRESUMO
Previous research from our laboratory in beef cattle suggests that the pre-ovulatory follicle size, maturity and subsequent susceptibility to gonadotropin are influenced by the length of progestagen treatment in artificial insemination programme in beef cows. To test this hypothesis, two experiments were conducted. In experiment 1, 35 anoestrous beef cows received an intravaginal sponge containing 200 mg of medroxyprogesterone acetate. The treatment lasted for 7 (n = 12), 8 (n = 11) or 9 (n = 12) days. Half of the animals in each group were injected with 0.7 mg of oestradiol benzoate (EB) at device removal (0 h) and the other half 24 h later. In experiment 2, 38 cycling beef cows were treated with the same protocols as in experiment 1. Ultrasound examinations were performed to determine the follicular diameter at device removal (dominant follicle), interval to ovulation and ovulatory follicle diameter. The dominant follicle of anoestrous cows with progestagen for 7 days (8.4 ± 1.6 mm) resulted smaller (p < 0.05) than the cows treated for 8 (10.5 ± 1.6 mm) and 9 days (10.6 ± 1.2 mm). However, regardless of the length of the treatments, ovulation time after device removal was longer (p < 0.05) when EB was injected 24 h after withdrawal than at 0 h in anoestrous cows (EB0 = 52.7 ± 4.0 h; EB24 = 70.8 ± 6.2 h) and in cyclic cows (EB0 = 50.0 ± 21.0 h; EB24 = 73.0 ± 20.0 h). In anoestrous cows, the treatment with progestagen for 9 days and EB at 24 h increased the diameter of the ovarian follicle (p = 0.033) but did not affect the diameter of the ovulatory follicle in cyclic cows. In conclusion, increasing the length of progestagen treatment for 8 or 9 days compared to 7 days increased the diameter of the dominant follicle, in anoestrous and cyclic beef cows. Oestradiol benzoate administered at device removal resulted in a shorter interval from device removal to ovulation compared with EB injection 24 h after the end of a progestagen treatment.
Assuntos
Bovinos/fisiologia , Estradiol/análogos & derivados , Sincronização do Estro/métodos , Medroxiprogesterona/farmacologia , Animais , Esquema de Medicação , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Medroxiprogesterona/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Ovulação/fisiologiaRESUMO
This study was conducted to investigate in early postpartum suckled beef cows with and without FSH pre-stimulation: (i) the influence of the postpartum period on the number and quality of oocytes recovered by ovum pick-up (OPU), (ii) the overall efficiency of the OPU/IVP embryos from days 30 to 80 postpartum and (iii) if repeated OPU negatively affect fertility following a fixed-time artificial insemination protocol. After parturition suckled Angus cows (n = 30) were divided in three groups (n = 10 group(-1)). All cows were anestrous at the commencement of experimental treatments (30.0 +/- 3.2 days postpartum, mean +/- SD; range 25-34 days). Group 1 treatments included: dominant follicle ablation (DFA), FSH treatment and OPU procedure 5 days after DFA. A total of 9 mg FSH (Ovagen) was administered s.c. once a day over 2 days at equal doses (4.5 + 4.5mg). For fertility test the cows received an intravaginal progesterone treatment from Days 78 to 86 postpartum and were fixed-time artificially inseminated (FTAI) at 56 and 72 h after device removal. Group 2: as cited for Group 1 with no FSH treatment. In both groups, OPU was repeated four times (Days 35, 49, 63 and 77 postpartum) and the collected oocytes classified as viable were in vitro matured, fertilized and presumptive embryos cultured for 8 days. Group 3 (Control FTAI): cows that had not previously aspirations were FTAI as Groups 1 and 2. Pregnancy was diagnosed by means ultrasonography 39 days after FTAI. The numbers (mean +/- SEM) of follicles visible and aspirated at the time of OPU in FSH-treated cows were greater (P < 0.05) than in non-treated cows (10.6 +/- 0.6 and 8.4 +/- 0.4 vs. 8.0 +/- 0.5 and 4.6 +/- 0.3, respectively). Following FSH treatment, the number (mean +/- SEM) of recovered oocytes per cow per OPU session and percentage of viable oocytes were greater in the treated (P < 0.05) than in non-treated animals (3.0 +/- 0.1 and 39.5% vs. 1.5 +/- 0.1 and 30.0%). The cleavage and embryo development rates were similar (P > 0.05) for both groups (14.8 and 6.4% vs. 16.6 and 5.5%). After FTAI the pregnancy rates were not different (P > 0.05) among groups (70, 60 and 90% for Groups 1, 2 and 3, respectively). We can conclude that (1) FSH-treated suckled postpartum cows can be a source of oocytes for in vitro fertilization and (2) repeated DFA/OPU applied during postpartum period did not affect the subsequent fertility following FTAI.
Assuntos
Desenvolvimento Embrionário/fisiologia , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Recuperação de Oócitos/métodos , Indução da Ovulação/métodos , Período Pós-Parto , Animais , Biópsia por Agulha Fina , Bovinos , Feminino , Fertilidade/efeitos dos fármacos , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Masculino , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/patologia , Período Pós-Parto/fisiologia , Gravidez , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia , Vagina/diagnóstico por imagemRESUMO
To evaluate ovarian response in Angus cows previously treated with progesterone (P4), animals were randomly assigned to two groups: T600 group (n=14), 600 mg of P4/day. P4 was injected from days 3 to 7 of the estrous cycle. On day 7, superovulatory treatments began. The control group (n=12) was given vehicle only. The superovulatory treatments in the control group began on days 7-9 of the estrous cycle. The superovulatory total treatment dose of 400mg NIH FSH P1 was given twice a day over a 4-day period. Ultrasonography of the ovaries was conducted 3 days preceding the initiation of superovulatory treatment, every 24h. In both groups, an additional ultrasonographic evaluation was made at 24h after the end of superovulatory treatment. Blood samples were collected 4 days preceding the initiation of superovulatory treatment, every 24h. Additional samples were taken from the P600 group for 12 day after of initiation of superovulatory treatment every 24h, except on the fifth day after the initiation of superovulatory treatment. In the P600 group, P4 concentrations were greater than in the control group (P<0.01) and remained over 1 ng/ml up to day 11 after beginning of superovulatory treatment. The diameter of the dominant follicle was larger in the animals of the control group (P<0.01). Cows of the P600 group had a greater number of Class I (3-4mm) follicles (P<0.01). A significant day and treatment effect (P<0.01) were observed in Class II (5-9 mm) follicles. Effects due to treatment on the number of Class III follicles (P<0.05) were observed. In the P600 group, no estrous post-superovulatory was observed and there were no ovulations that occurred. Conversely, 100% of the cows of the control group showed estrous. In the P600 group, there were a greater number of Class III follicles (P<0.01) and a lesser number of Class II follicles (P<0.05) at 24h after the end of superovulatory. In the control group, 66.7% of the cows responded to superovulatory treatments. In conclusion, the daily administration of 600 mg of P4, from days 3 to 7 of the estrous cycle, produces an increase of plasma concentrations of this hormone from day 4, resulting in changes in follicular dynamics (absence of follicles greater than 10mm of diameter and an increase of the population of Class I follicles). As to the ovarian stimulation using Folltropin V in animals receiving a daily injection of 600 mg of P4 from days 3 to 7 of the estrous cycle, a greater population of follicles>or=10mm developed by 24h after superovulatory treatments were completed.
Assuntos
Bovinos/fisiologia , Ovário/efeitos dos fármacos , Progesterona/administração & dosagem , Progesterona/farmacologia , Superovulação/efeitos dos fármacos , Animais , Esquema de Medicação/veterinária , Ciclo Estral , Feminino , Progesterona/sangueRESUMO
To determine a dose of progesterone (P4) that allow ovarian follicular wave control, Aberdeen Angus cows were randomly assigned into four groups: T600 (n=5), 600 mg of P4/day; T400 (n=5), 400 mg of P4/day; T200 (n=4), 200mg of P4/day and Control (n=4) (excipient only). Progesterone was injected from day 3 to 9 of estrous cycle. Ultrasonographies and blood sample collections were performed daily from day 2 to 10 and on day 15 of the estrous cycle. Additionally, an ultrasonographic study was conducted on day 13. Progesterone concentrations were different among all groups (P<0.01). The diameter of the dominant follicle was greater for control than for T200, T400 and T600 groups (P<0.01); there was no difference between T200 and T400 (P>0.05), but they had a greater diameter follicle than the T600 group (P<0.01). The growth rate of the dominant follicle between day 3 and 7 of estrous cycle was greater for control group (1.63+/-0.3 mmday(-1)) than for T200 (0.56+/-0.19 mmday(-1), P<0.05), T400 (0.6+/-0.23 mmday(-1), P<0.05) and T600 (0.11+/-0.13 mmday(-1), P<0.01) groups. The mean number of class I follicles (3-4mm) per day for the entire experimental period was less for the control group than for T200 (P<0.05), T400 and T600 (P<0.01) groups (3.7+/-1.3; 5.3+/-1.3; 6.6+/-1.8 and 8.1+/-1.9, respectively). The mean number for the T200 group was less than for T600 (P<0.05) and similar for T400 and T600 groups (P>0.05). The number of class III follicles was greater for control group than for the other groups (P<0.01). T200 and T400 groups had similar numbers of class III follicles (P>0.05) and both had greater numbers of follicles than the T600 group (P<0.05). The diameter of the corpus luteum of the T600 group (15.8+/-1.6 mm) was less than for control (21.0+/-2.5 mm, P<0.01), T200 (19.3+/-2.7 mm, P<0.01) and T400 (20.0+/-2.2 mm) groups (P<0.05). The mean diameter of corpus luteum of T200 was similar to T400 (P>0.05), but different from the control group (P<0.05). In conclusion, the daily intramuscular administration of 200mg or more of progesterone from day 3 to 9 of the estrous cycle indicates that plasma concentrations of progesterone can be used to modify the pattern of follicular development during the follicular wave. From day 5 of the estrous cycle, progesterone concentrations greater than 15 ng/ml (T600 group: 600 mg/day of progesterone from day 3 to 9 of the estrous cycle) inhibit dominant follicle development, increase the class I follicle populations (3-4 mm) and diminish the development of the corpus luteum.
Assuntos
Bovinos/fisiologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Progesterona/administração & dosagem , Animais , Corpo Lúteo/diagnóstico por imagem , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/fisiologia , Relação Dose-Resposta a Droga , Ciclo Estral , Feminino , Folículo Ovariano/diagnóstico por imagem , Progesterona/sangue , UltrassonografiaRESUMO
Embryo development depends on maternal and embryonic factors. When occurs in vitro, embryos secrete factors that stimulate their development. The purpose of this study was to investigate the possible effects of embryos at morula stage on mouse embryo development in vitro. To obtain conditioned media (CM), morulas were cultured in groups of 5 (CM5) or 10 (CM10) in microdrops of Ham-F10 culture medium during 24 h and later they were removed. Subsequently, 365 morulas were cultured in CM5 and CM10 or in Ham-F10 media (as control group). No differences in blastocyst formation could be found between embryos cultured for 24h in Ham-F10, CM5 or CM10 (49.66, 53.04, 60.00% respectively). However, CM5 significantly increased differentiation in embryos cultured for 48h as compared to Ham-F10 medium (80.00% and 64.14 respectively). The CM5 caused a significant increase in the hatching rate compared to Ham-F10 evaluated at 78 and 96 h of culture (66.96 vs. 52.41% and 70.43 vs. 55.17%, respectively). After 72, 78 and 96h of culture the hatching rate for embryos cultured in CM10 was significantly higher than that in Ham-F10 (64.76 vs. 47.59%, 67.62 vs. 52.41% and 73.33 vs. 55.17%, respectively). At 48h of culture, differences between CM5, CM10 and Ham-F10 were not observed. These results suggest that preimplantational mouse embryos produce trophic factor/factors that enhance the differentiation and hatching process.
Assuntos
Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Animais , Blastocisto , Diferenciação Celular , Meios de Cultura/farmacologia , Meios de Cultivo Condicionados/farmacologia , Embrião de Mamíferos/citologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Cultura de Órgãos/métodos , Fatores de TempoRESUMO
Embryo development depends on maternal and embryonic factors. When occurs in vitro, embryos secrete factors that stimulate their development. The purpose of this study was to investigate the possible effects of embryos at morula stage on mouse embryo development in vitro. To obtain conditioned media (CM), morulas were cultured in groups of 5 (CM5) or 10 (CM10) in microdrops of Ham-Fl0 culture medium during 24h and later they were removed. Subsequently, 365 morulas were cultured in CM5 and CM10 or in Ham-F10 media (as control group). No differences in blastocyst formation could be found between embryos cultured for 24h in Ham-F1O, CM5 or CM10 (49.66, 53.04, 60.00% respectively). However, CM5 significantly increased differentiation in embryos cultured for 48h as compared to Ham-FlO medium (80.00% and 64.14 respectively). The CM5 caused a significant increase in the hatching rate compared to Ham-F10 evaluated at 78 and 96h of culture (66.96 vs. 52.41% and 70.43 vs. 55.17%, respectively). After 72, 78 and 96h of culture the hatching rate for embryos cultured in CM10 was significantly higher than that in Ham-F10 (64.76 vs. 47.59%, 67.62 vs. 52.41% and 73.33 vs. 55.17%, respectively). At 48h of culture, differences between CM5, CMl0 and Ham-F10 were not observed. These results suggest that preimplantational mouse embryos produce trophic factor/factors that enhance the differentiation and hatching process
Assuntos
Animais , Camundongos , Desenvolvimento Embrionário e Fetal/fisiologia , Homeostase/fisiologia , Camundongos/embriologia , Crescimento/fisiologia , Animais de Laboratório/embriologia , Substâncias de Crescimento , Substâncias de Crescimento/deficiênciaRESUMO
Embryo development depends on maternal and embryonic factors. When occurs in vitro, embryos secrete factors that stimulate their development. The purpose of this study was to investigate the possible effects of embryos at morula stage on mouse embryo development in vitro. To obtain conditioned media (CM), morulas were cultured in groups of 5 (CM5) or 10 (CM10) in microdrops of Ham-Fl0 culture medium during 24h and later they were removed. Subsequently, 365 morulas were cultured in CM5 and CM10 or in Ham-F10 media (as control group). No differences in blastocyst formation could be found between embryos cultured for 24h in Ham-F1O, CM5 or CM10 (49.66, 53.04, 60.00% respectively). However, CM5 significantly increased differentiation in embryos cultured for 48h as compared to Ham-FlO medium (80.00% and 64.14 respectively). The CM5 caused a significant increase in the hatching rate compared to Ham-F10 evaluated at 78 and 96h of culture (66.96 vs. 52.41% and 70.43 vs. 55.17%, respectively). After 72, 78 and 96h of culture the hatching rate for embryos cultured in CM10 was significantly higher than that in Ham-F10 (64.76 vs. 47.59%, 67.62 vs. 52.41% and 73.33 vs. 55.17%, respectively). At 48h of culture, differences between CM5, CMl0 and Ham-F10 were not observed. These results suggest that preimplantational mouse embryos produce trophic factor/factors that enhance the differentiation and hatching process
Assuntos
Animais , Camundongos , Animais de Laboratório/embriologia , Crescimento/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Substâncias de Crescimento , Homeostase/fisiologia , Camundongos/embriologia , Substâncias de Crescimento/deficiênciaRESUMO
Embryo development depends on maternal and embryonic factors. When occurs in vitro, embryos secrete factors that stimulate their development. The purpose of this study was to investigate the possible effects of embryos at morula stage on mouse embryo development in vitro. To obtain conditioned media (CM), morulas were cultured in groups of 5 (CM5) or 10 (CM10) in microdrops of Ham-F10 culture medium during 24 h and later they were removed. Subsequently, 365 morulas were cultured in CM5 and CM10 or in Ham-F10 media (as control group). No differences in blastocyst formation could be found between embryos cultured for 24h in Ham-F10, CM5 or CM10 (49.66, 53.04, 60.00
respectively). However, CM5 significantly increased differentiation in embryos cultured for 48h as compared to Ham-F10 medium (80.00
and 64.14 respectively). The CM5 caused a significant increase in the hatching rate compared to Ham-F10 evaluated at 78 and 96 h of culture (66.96 vs. 52.41
and 70.43 vs. 55.17
, respectively). After 72, 78 and 96h of culture the hatching rate for embryos cultured in CM10 was significantly higher than that in Ham-F10 (64.76 vs. 47.59
, 67.62 vs. 52.41
and 73.33 vs. 55.17
, respectively). At 48h of culture, differences between CM5, CM10 and Ham-F10 were not observed. These results suggest that preimplantational mouse embryos produce trophic factor/factors that enhance the differentiation and hatching process.