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1.
Reprod Domest Anim ; 51(4): 575-84, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27342233

RESUMO

The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross-breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α-MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non-cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey's and Dunnett's tests) and chi-square test (χ(2) ). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.


Assuntos
Bovinos , Hormônio do Crescimento/farmacologia , Folículo Ovariano/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Hormônio do Crescimento/administração & dosagem , Folículo Ovariano/ultraestrutura , Fatores de Tempo , Técnicas de Cultura de Tecidos
2.
Reprod Domest Anim ; 51(3): 435-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27099180

RESUMO

This study aimed at assessing the effect of different concentrations of the growth factor similar to insulin 1 (IGF-1) in the development, survival and ultrastructure of the bovine preantral follicles cultured in situ. Fragments of bovine ovarian cortical tissue were cultured during 1 and 7 days in 1 ml of α-MEM(+) , supplemented with different concentrations of human recombinant IGF-1 (0, 30, 70 and 100 ng/ml), in an incubator at 37°C and 5% of CO2 in 24-well plates with total replacement of the medium every 2 days. Non-cultured ovarian fragments (control) and ovarian fragments cultured during 1 and 7 days were processed for classic histology, mechanical isolation and electron transmission microscopy (ETM). Parameters such as normality, viability, activation, development, diameter and ultrastructure were evaluated. All statistical analyses were carried out using sas Version 9.2. The results showed that the percentage of follicles morphologically normal in the IGF-1 30 ng/ml treatment was similar to the fresh control (p > 0.05) both on the day 1 and on the day 7 of in vitro culture. In the viability analysis, the cultured treatments maintained the percentage of viable follicles during the entire culture period (p > 0.05). After 7 days of culture, the IGF-1 30 ng/ml treatment showed higher percentages of developing follicles (48.33%) than those of the fresh control (22.22%) and the cultured treatments (p < 0.05). Also, after 7 days of culture, IGF-1 30 ng/ml presented a higher follicular diameter when compared to the control and other concentrations of IGF-1 tested. Ultrastructurally, the non-cultured control and IGF-1 30 ng/ml, after 7 days of culture, showed conserved oocytes, nuclei and organelles. Hence, it is concluded that IGF-1 30 ng/ml was the most efficient concentration for the development of bovine preantral follicles cultured in vitro.


Assuntos
Fator de Crescimento Insulin-Like I/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Animais , Bovinos , Núcleo Celular/ultraestrutura , Meios de Cultura , Relação Dose-Resposta a Droga , Feminino , Humanos , Oócitos , Organelas/ultraestrutura , Folículo Ovariano/ultraestrutura , Proteínas Recombinantes , Fatores de Tempo , Técnicas de Cultura de Tecidos
3.
Arq. bras. med. vet. zootec ; 64(2): 349-358, abr. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-622487

RESUMO

This study reported the effects of prostaglandin (PGF2a) administration 10 days apart on reproductive parameters of cyclic artificial inseminated (AI) nulliparous Alpine (n=9) and Saanen (n=9) goats. Animals received two doses of 22.5mg PGF2a 10 days apart. After 1st and 2nd PGF2a administrations, estrus was monitored at 12 h intervals, with a buck teaser. Plasma progesterone concentration (ng/mL) was determined from blood sampled on day 0 (1st PGF2a) and the following 5, 10 (2nd PGF2a), 15, 20, 25 and 30 days. After the onset of the second estrus, females were transrectally (5 MHz probe) scanned at 4 hour intervals until at least 8h after ovulation. Pregnancy was checked through transrectal ultrasound on days 20, 25, 30, 35 and 90 after insemination. All parameters studied did not differ between breeds (P>0.05). Estrous response and interval to estrus, respectively, after 1st (78.9% and 50.6±17.2h) and 2nd PGF2a (88.9% and 50.0±14.8h) administration did not differ (P>0.05). Overall animals ovulating (100.0%), interval to ovulation after 2nd PGF2a (64.5±19.5h) and after estrous onset (18.0±9.1h), ovulation rate (1.3±0.5), diameter of ovulatory follicle (8.1±1.1mm) were recorded. Embryo loss occurred before day 30 of pregnancy. Estrus can be efficiently synchronized in nulliparous Alpine and Saanen goats with two doses of prostaglandin 10 days apart.


Relataram-se os efeitos da aplicação de prostaglandina sobre características reprodutivas de cabras leiteiras nulíparas cíclicas. Cabras Alpinas (n=9) e Saanen (n=9) receberam duas doses de 22,5mg PGF2a com 10 dias de intervalo. A progesterona plasmática (ng/mL) foi determinada a partir de amostras de sangue coletadas nos dias 0 (primeira dose), 5, 10 (segunda dose), 15, 20, 25 e 30. Após início do segundo estro, as fêmeas foram monitoradas por ultrassonografia transretal a cada quatro horas até oito horas após a ovulação. A gestação foi verificada por ultrassonografia transretal nos dias 20, 25, 30, 35 e 90 após a segunda dose. As características estudadas foram semelhantes entre as raças (P>0,05). Animais em estro e o intervalo parto-estro de, respectivamente, 78,9% e 50,6±17,2h e 88,9% e 50,0±14,8h após a primeira e segunda administrações de prostaglandina, não diferiram (P>0,05). Todas as cabras ovularam e registraram-se valores do intervalo parto-ovulação após a segunda aplicação de prostaglandina de 64,5±19,5h e após início do estro de 18,0±9,1h, a taxa de ovulação de 1,3±0,5 e diâmetro do folículo ovulatório de 8,1±1,1mm. Perda embrionária ocorreu antes de 30 dias de gestação. O estro pode ser eficientemente sincronizado em cabras leiteiras núliparas com duas doses de prostaglandina intervaladas de 10 dias.

4.
Artigo em Português | VETINDEX | ID: vti-447870

RESUMO

The effect of the r-bST injection was evaluated on the goats estrous cycles. Twenty-four Toggenburg does were used in two treatments: T1 (n=12) treated with r-bST; and T2 (n=12) treated with saline solution (control). After the first r-bST injection, the estrous cycles were checked between two estrus. The estrous cycle length and interovulatory period of the goats did not differ between treatments (P>0.05). Estrous cycles with two, three and four waves of follicular growth were observed. The number of waves during the estrous cycle were not affected by the r-bST treatment (P>0.05). The number of 3mm follicles was different between T1 and T2 (P 0.05) for estrous cycles with two (15.3±1.2 x 8.1±2.0), three (12.2±0.8 x 8.3±1.9) or four (12.7±1.7 x 8.8±2.5) waves. The dominant follicle of the second wave was smaller (P 0.05) than the one of the first and third waves and smaller than the one of the ovulatory wave. The progesterone concentration during the estrous cycle of the animals did not differ (P>0.05) between treatments. The r-bST did not affect the ovarian response during the estrous cycle. The r-bST not affected the follicular dynamic of Toggenburg lactating does, but increased the number of emerging follicles >3mm during the estrous cycle.


Avaliou-se o efeito da injeção de somatotropina bovina recombinante (r-bST) sobre o ciclo estral de cabras. Foram utilizadas 24 fêmeas da raça Toggenburg, distribuídas em dois tratamentos: T1 (n=12), cabras tratadas com r-bST; e T2 (n=12), cabras tratadas com solução salina (controle). A partir da primeira injeção do tratamento, acompanhou-se o ciclo dos animais em estro até o estro subseqüente. O comprimento médio do ciclo estral e o período interovulatório não diferiram (P>0,05) entre os tratamentos. Foram verificados ciclos estrais de duas, três e quatro ondas de crescimento folicular. Não houve diferença (P>0,05) entre os tratamentos quanto ao número de ondas do ciclo estral. O número de folículos detectados com diâmetro >3mm nas cabras do T1 foi maior (P 0,05) que naquelas do T2 nos ciclos com duas (15,3±1,2 x 8,1±2,0), três (12,2±0,8 x 8,3±1,9) e quatro (12,7±1,7 x 8,8±2,5) ondas. O folículo dominante da segunda onda foi menor (P 0,05) que o da primeira e terceira ondas e também menor que o da onda ovulatória tanto para T1 quanto para T2. A concentração sérica de progesterona durante o ciclo estral não foi influenciada pelos tratamentos com r-bST (P>0,05). A r-bST não alterou a dinâmica folicular de cabras lactantes da raça Toggenburg, mas promoveu o aumento do número de folículos recrutados ³3mm durante o ciclo estral.

5.
Artigo em Português | VETINDEX | ID: vti-447758

RESUMO

The objective of the experiment was to study the total cholesterol and high-density lipoprotein (HDL) levels in crossbred heifers treated with bovine recombinant somatotropina (rbST). Blood samples were collected for two estrous cycles, normal and superovulated, from 26 animals randomly distributed into two treatments: T1 - injected with 500mg rbST on day 3 of estrous cycle and T2 - control. The lipidic metabolite levels were determined by an enzymatic method, and plasma levels of total cholesterol and HDL in normal estrous cycle did not differ (P>0.05) between treatments: 87.9 and 25.8mg/dl for T1 and 85.9 and 26.7mg/dl for T2, respectively. The superovulated estrous cycle was divided into three periods: P1 - from estrus to artificial insemination (AI) (0 to 15th day), P2 - from AI to embryo collection (15th to 21st day) and P3 - from collection to the end of the experiment (21st to 27th day). The rbST treatment did not affect the HDL and cholesterol levels in the P1 (P>0.05), but did so in P2 and P3: 29.0 and 88.5mg/dl (T1) and 27.1 and 81.8mg/dl (T2) during P2; 30.4 and 88.0mg/dl (T1) and 26.6 and 80.5mg/dl (T2) during P3, respectively (P 0.01).


O objetivo do experimento foi o de estudar as concentrações plasmáticas de colesterol total e lipoproteína de alta densidade (HDL) em novilhas mestiças tratadas com somatotropina bovina recombinante (rbST). Coletas de sangue foram feitas durante dois ciclos estrais, normal e superovulado, em 26 fêmeas distribuídas em dois tratamentos: T1 = aplicação de 500mg de rbST no terceiro dia do ciclo estral utilizado para a superovulação e T2 = controle. Análises dos metabólitos sangüíneos foram feitas utilizando-se o método enzimático, cujas concentrações médias plasmáticas de colesterol total e de HDL durante o ciclo estral normal não foram diferentes (P>0,05) entre os dois tratamentos: 87,9 e 25,8mg/dl e 85,9 e 26,7mg/dl para T1 e T2, respectivamente. O ciclo estral utilizado para a superovulação foi dividido em três períodos: P1 = do estro à inseminação artificial (0 ao15º dia), P2 = da inseminação artificial até a coleta de embriões (15º ao 21º dia) e P3 = da coleta até o final do período experimental (21º ao 27º dia). As concentrações plasmáticas de colesterol total e HDL no P1 não diferiram entre os tratamentos (P>0,05). Em P2 e P3 houve diferença nas concentrações de HDL e colesterol total entre os dois tratamentos: 29,0 e 88,5mg/dl (T1) e 27,1 e 81,8mg/dl (T2) no P2; e 30,4 e 88,0mg/dl (T1) e 26,6 e 80,5mg/dl (T2) no P3, respectivamente (P 0,01).

6.
Artigo em Português | VETINDEX | ID: vti-447757

RESUMO

Twenty-six crossbred heifers were used to study daily ovarian follicular growth by ultrasonography from the estrus, for one or two consecutive estrous cycles. The follicle diameters of the first and second large follicles were determined for each ovary. The follicular dynamic in crossbred heifer was characterized by the predominance of three follicular waves (58.3%), over the two waves (33.3%). For cycles with three waves, the waves 1, 2 and 3 could be detected on days 0.4, 8.2 and 15.9 and for cycles with two waves, the waves 1 and 2 begun, on average, on days 0.4 and 9.7. The dominant follicle maximum diameters were 12.7 and 13.3mm, and 12.2, 10.0 and 11.7mm, in the estrous cycles with two and three waves, respectively. The maximum diameter reached by the second largest follicle (subordinate) was 7.0mm, in the estrous cycle with two or three follicular waves. The growth rates (mm/day) for dominant and subordinate follicles were 1.1 and 1.0, and the atresia rates were 1.1 and 1.2, respectively. One heifer exhibited four follicular waves, while two others presented just one follicular wave.


O estudo do crescimento folicular ovariano foi realizado em 26 novilhas mestiças Holandês-Zebu, por meio de acompanhamento ultra-sonográfico diário a partir do dia do estro, por um ou dois ciclos estrais consecutivos. Foram medidos os diâmetros do maior e segundo maior folículos presentes em cada ovário, detectando-se predominância de ciclos com três ondas de crescimento folicular (58,3%) sobre ciclos com duas ondas (33,3%). O início das ondas foi detectado nos dias 0,4 e 9,7 para os ciclos com duas ondas e nos dias 0,4, 8,2 e 15,9 para os ciclos com três ondas de crescimento folicular. Os diâmetros máximos dos folículos dominantes nos ciclos de duas ondas foram de 12,7 e 13,3mm e de 12,2, 10,0 e 11,7mm para os ciclos com três ondas. Para os folículos subordinados, os diâmetros médios foram de 7,0mm, independente do número de ondas. As taxas de crescimento folicular foram de 1,1 e 1,0mm/dia, e as taxas de atresia foram de 1,1 e 1,2mm/dia para os folículos dominantes e subordinados, respectivamente. Um animal apresentou quatro ondas de crescimento folicular, enquanto dois animais apresentaram um ciclo estral com apenas uma onda folicular.

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