RESUMO
This study evaluated the role of progesterone (P4) and medroxyprogesterone acetate (MAP) on the molecular status of immature cumulus-oocyte complexes (COCs) and the implications for oocyte quality in sheep. The number of viable COCs per ewe and the rate of COCs screened for developmental competence by brilliant cresyl blue positive (BCB+) were similar (P > 0.05), respectively, across treatments (P4: 7.7 ± 0.7 and 4.7 ± 1.2; MAP: 5.7 ± 1.0 and 3.5 ± 2.3; and control: 5.7 ± 1.1 and 3.6 ± 2.4). The COCs' gene expression was altered by exogenous progestogens compared with the control group: markers of steroidogenic pathway (FSH receptor [FSHr], LH receptor [LHr], and estradiol receptor α) and of quality (zygote arrest 1, growth differentiation factor 9, and B-cell lymphoma 2) were in abundance in P4 (P < 0.05). In addition, reelin protein (RELN) was downregulated, and Bcl-2 was upregulated in MAP (P < 0.05). In the P4 vs MAP comparison, FSHr, LHr, and RELN genes were upregulated (P < 0.05) in the P4 group. In conclusion, P4 and MAP promoted dissimilar effects on transcriptome profiling of immature BCB-selected COCs, possibly due to the differences in the chemical structure of progestogens and concentrations of serum P4. Exogenous P4 impacted positively on the profile of genes related to oocyte quality.
Assuntos
Células do Cúmulo/metabolismo , Expressão Gênica/efeitos dos fármacos , Oócitos/metabolismo , Progestinas/administração & dosagem , Ovinos , Animais , Moléculas de Adesão Celular Neuronais/genética , Proteínas do Ovo , Receptor alfa de Estrogênio/genética , Proteínas da Matriz Extracelular/genética , Feminino , Fator 9 de Diferenciação de Crescimento/genética , Acetato de Medroxiprogesterona/administração & dosagem , Proteínas do Tecido Nervoso/genética , Oócitos/fisiologia , Progesterona/administração & dosagem , Progesterona/sangue , Receptores do FSH/genética , Receptores do LH/genética , Proteína Reelina , Serina Endopeptidases/genéticaRESUMO
This study examined the effects of exogenous hCG administration on ovarian function and pregnancy rates in estrous-induced dairy goats during the transition into the breeding season. Eighty-six Toggenburg does received 60 mg of medroxyprogesterone acetate intravaginal sponge for 6 d plus 200 IU of equine chorionic gonadotropin and 30 µg of d-cloprostenol i.m. 24 h before sponge removal, and were then bred for 96 h. Seven days (D7) after first mating the does received either 1 mL of saline (the control group, n = 43) or 300 IU of hCG (the hCG-treated group, n = 43) i.m. Transrectal ovarian ultrasonography (B-mode and color Doppler) was performed on D7, D13, D17, and D21 and ultrasonographic pregnancy detection on D30. Pregnancy rate was higher (P < 0.05) in hCG-treated goats (90.7%; 39/43) than that in control animals (74.4%; 32/43). Accessory luteal structures (ALSs) were detected in 46.5% (20/43) of hCG-treated does. All hCG-treated does that had ALSs and 82.6% of goats without ALS post-treatment remained pregnant. The total luteal area increased (P < 0.05) from D7 to D13 in pregnant animals of both groups, whereas mean vascular area declined (P < 0.05) by D21 in all nonpregnant does. Serum progesterone concentrations increased (P < 0.05) on D21 in pregnant goats of both groups, but they were related to changes in luteal tissue content only in control does throughout the present study. Mean daily numbers of small- and medium-sized antral follicles decreased (P < 0.05) only in pregnant animals of both groups with a decline in medium follicle numbers occurring earlier in hCG-treated (D13) compared with control does (D17). To summarize, a single dose of hCG given on D7 after estrus was followed by a decrease in the number of medium-sized antral follicles in gestating hCG-treated does, induced the formation of ALSs in ~47% of all hCG-treated does, and significantly increased the pregnancy rate in estrous-induced Toggenburg goats in the transition to the breeding season.
Assuntos
Gonadotropina Coriônica/farmacologia , Cabras/fisiologia , Taxa de Gravidez , Substâncias para o Controle da Reprodução/farmacologia , Animais , Esquema de Medicação , Feminino , Humanos , GravidezRESUMO
The aim of the present study was to characterise the roles of intrafollicular oestradiol production and granulosa cell (GC) expression of the LH receptor (LHR) gene and its isoforms during follicular deviation in Bos indicus. Follicular wave emergence was synchronised in heifers from a Bos taurus dairy (Holstein; n=10) and a B. indicus dairy breed (Gir; n=10). Follicles were aspirated individually at sizes corresponding to the periods of predeviation, deviation and postdeviation. Intrafollicular oestradiol (IF-E2) and progesterone (IF-P4) concentrations were determined in the follicular fluid (FF) by radioimmunoassay, and relative expression of P450 aromatase (CYP19A1) and LHR forms was evaluated in GC using real-time quantitative-polymerase chain reaction. Despite differences in the size of the dominant follicle at deviation, changes in CYP19A1 expression and IF-E2 concentrations were similar in follicles of the same diameter in both breeds. A peak in total LHR expression occurred after follicular deviation in association with low expression of LHR isoforms. The results suggest that regulation of LHR function by sequential changes in the expression pattern of LHR isoforms may play a role in the early deviation of the dominant follicle, as observed in B. indicus breeds.
Assuntos
Estradiol/biossíntese , Folículo Ovariano/metabolismo , Isoformas de Proteínas/metabolismo , Receptores do LH/metabolismo , Processamento Alternativo , Animais , Bovinos , Feminino , Líquido Folicular/metabolismo , Expressão Gênica , Progesterona/biossíntese , Isoformas de Proteínas/genética , Receptores do LH/genéticaRESUMO
Ultrasound-guided transvaginal follicle aspiration is used to recover cumulus-oocyte complexes (for IVF) and to synchronize follicular wave emergence (ablation of dominant follicle). Although aspirated follicles are generally supposed to undergo immediate atresia, there are indications that they may remain active. The objective was to evaluate the occurrence and characteristics of residual follicles (RF) after transvaginal follicle aspiration in cattle. Ovarian follicular wave emergence was synchronized in Holstein cows (N = 13) in the presence (groups 1 and 3) or absence (groups 2 and 4) of norgestomet implants. The largest follicle was aspirated at a diameter of 8 mm (groups 1 and 2) or 12 mm (groups 3 and 4). Ovarian follicles were visualized (transrectal ultrasonography) every 12 h after wave emergence. Follicular fluid samples were collected from the largest follicle and from the ensuing RF and concentrations of estradiol and progesterone were determined. After aspiration, 73.2% (52/71) of the follicles refilled with fluid, and a new antrum was detected 12 to 24 h later. Norgestomet did not affect (P > 0.05) RF occurrence or diameter, but in RF from group 4, concentrations of estradiol decreased (-530.7 ± 133.9 ng/mL; P < 0.01) whereas progesterone increased (+429.6 ± 171.7 ng/mL; P < 0.05) relative to preaspiration. In RF, there were three steroidogenesis patterns: (1) high estradiol concentration and high estradiol:progesterone ratio (estradiol-active RF); (2) low estradiol, but high progesterone concentrations (luteinized RF); and (3) low estradiol and low progesterone concentrations (inactive RF). Estradiol-active RF were more likely (P < 0.05) from follicles with high estradiol concentrations (regardless of diameter). In conclusion, fluid-filled structures (RF) with variable steroid production patterns are frequently formed after ultrasound-guided follicle aspiration. The occurrence and features of these RF depended on the diameter and status of these follicles before aspiration.
Assuntos
Bovinos , Folículo Ovariano/fisiologia , Coleta de Tecidos e Órgãos/veterinária , Ultrassonografia/veterinária , Animais , Bovinos/anatomia & histologia , Bovinos/fisiologia , Células do Cúmulo , Estradiol/análise , Feminino , Líquido Folicular/química , Oócitos , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/cirurgia , Pregnenodionas/administração & dosagem , Progesterona/análise , Sucção/veterinária , Coleta de Tecidos e Órgãos/métodosRESUMO
The objective was to investigate the influence of corpora lutea physical and functional characteristics on pregnancy rates in bovine recipients synchronized for fixed-time embryo transfer (FTET). Crossbred (Bos taurus taurus x Bos taurus indicus) nonlactating cows and heifers (n=259) were treated with the following protocol: 2mg estradiol benzoate (EB) plus an intravaginal progesterone device (CIDR 1.9g progesterone; Day 0); 400 IU equine chorionic gonadotropin (eCG; Day 5); prostaglandin F(2alpha) (PGF(2alpha)) and CIDR withdrawal (Day 8); and 1mg EB (Day 9). Ovarian ultrasonography and blood sample collections were performed on Day 17. Of the 259 cattle initially treated, 197 (76.1%) were suitable recipients; they received a single, fresh, quality grade 1 or 2 in vivo-derived (n=90) or in vitro-produced (n=87) embryo on Day 17. Pregnancy rates (23 d after embryo transfer) were higher for in vivo-derived embryos than for in vitro-produced embryos (58.8% vs. 31.0%, respectively; P<0.001). Mean (+/-SD) plasma progesterone (P(4)) concentration was higher in cattle that became pregnant than that in nonpregnant cattle (5.2+/-5.0 vs. 3.8+/-2.4 ng/mL; P=0.02). Mean pixel values (71.8+/-1.3 vs. 71.2+/-1.1) and pixel heterogeneity (14.8+/-0.3 vs. 14.5+/-0.5) were similar between pregnant and nonpregnant recipients (P>0.10). No significant relationship was detected between pregnancy outcome and plasma P(4), corpus luteum area, or corpus luteum echotexture. Embryo type, however, affected the odds of pregnancy. In conclusion, corpus luteum-related traits were poor predictors of pregnancy in recipients. The type of embryo, however, was a major factor affecting pregnancy outcome.
Assuntos
Bovinos/fisiologia , Corpo Lúteo/fisiologia , Transferência Embrionária/veterinária , Administração Intravaginal , Animais , Gonadotropina Coriônica/administração & dosagem , Corpo Lúteo/anatomia & histologia , Dinoprosta/administração & dosagem , Transferência Embrionária/métodos , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Feminino , Fertilização in vitro/veterinária , Ovário/diagnóstico por imagem , Gravidez , Progesterona/administração & dosagem , Progesterona/sangue , Superovulação , Resultado do Tratamento , UltrassonografiaRESUMO
Foram analisadas 252 amostras de fezes de cães e gatos provenientes dos municípios do Rio de Janeiro e Niterói no período de 1999 a 2000. Foram 212 (84,12
Assuntos
Cães/parasitologia , Gatos , Fezes , ParasitosRESUMO
Foram analisadas 252 amostras de fezes de cães e gatos provenientes dos municípios do Rio de Janeiro e Niterói no períodode 1999 a 2000. Foram 212 (84,12%) amostras de cães e 40 (15,87%) de gatos. Do total de amostras examinadas 81(32,14%), foram positivas para pelo menos uma espécie de parasita. Dos 212 exames de material fecal canino, 70 (33,01%)estavam positivos e de felinos 11 (27,5%). As infecções mistas foram observadas em 10 amostras caninas (14,28%) e quatrofelinas (36,36%). Nas amostras caninas, ovos de ancilostomídeos foram os mais encontrados em 43 (61,43%) amostras,enquanto os coccídeos foram mais freqüentemente observados nas fezes de felinos em três (27,27%) amostras. Quanto àidade dos animais, 37 (52,85%) amostras positivas eram provenientes de animais com mais de 1 ano de idade, indicandoprovável vermifugação dos filhotes, enquanto nos gatos a faixa etária mais parasitada foi de menos de seis meses, com 7(63,63%) positivos.