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1.
J Reprod Dev ; 57(1): 159-62, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20962459

RESUMEN

The relationship between the peripheral concentrations of estradiol-17ß (E(2)) and the preovulatory characteristics of cumulus oocyte complexes (COCs) during superovulation treatment was investigated in Japanese Black cows. A superovulation regimen with FSH treatment in a descending manner was commenced on day 7 (n=3) or day 10 (n=2) of the estrous cycle (day 0=estrus). Peripheral blood was collected to measure E(2) concentrations twice a day throughout the treatment. Ovariectomies were performed at 100 h after the initial FSH treatment in five cows. Every follicle more than 8 mm in diameter was isolated from the ovaries, and cumulus-oocyte complexes (COCs) were gently aspirated. The COCs were then separated into three groups based on the characteristics of the cumulus (compact, expanded and denuded) and subgrouped based on the stage of the nucleus in the oocytes (GV, GVBD). Plasma E(2) concentrations tended to increase gradually and reached the peak level at around 84 h (E(2)-84: n=3) or 96 h (E(2)-96: n=2) after the initial FSH treatment. The ratio of COCs with expanded cumulus was significantly higher in E(2)-84 than in E(2)-96 (P<0.01). However, there was no difference in the ratio of oocytes showing GVBD between E(2)-84 and E(2)-96 (P=0.73), and the characteristics of the cumulus did not affect the stage of the nucleus in the oocytes in either groups (compact, expanded and nude; P=0.61, 0.81 and 1.00). It was possible that the time until the peak plasma E(2) concentrations after the FSH treatment could become an indicator for the maturation of follicles and oocytes in preovulatory follicles during superovulation treatment in Japanese Black cows.


Asunto(s)
Bovinos/fisiología , Células del Cúmulo/efectos de los fármacos , Transferencia de Embrión/veterinaria , Estradiol/sangre , Oocitos/efectos de los fármacos , Oogénesis/efectos de los fármacos , Superovulación/sangre , Animales , Biomarcadores/sangre , Cruzamiento , Núcleo Celular/efectos de los fármacos , Forma del Núcleo Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Células del Cúmulo/citología , Transferencia de Embrión/métodos , Femenino , Hormona Folículo Estimulante/farmacología , Fase Folicular/sangre , Oocitos/citología , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Superovulación/efectos de los fármacos , Factores de Tiempo
2.
J Vet Sci ; 9(3): 273-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18716447

RESUMEN

This study was designed to evaluate the reproductive performance of Japanese black cows following the 3rd injection of gonadotropin releasing hormone (GnRH) analogue administered concurrently with Ovsynch-based treatment on day 6 (day 1 = the day of ovulation). In Experiment 1, 12 cows were allocated into three groups: a control group that was subjected to Ovsynch treatment and then injected with a placebo on day 6; group 1 (Ovsynch + GnRH), which was subjected to Ovsynch treatment and was injected with GnRH analogue on day 6, and group 2 (Ovsynch + controlled internal drug-release (CIDR) + GnRH), which received Ovsynch-CIDR treatment and was injected with GnRH analogue on day 6. Blood collection and ultrasonographic observation of the ovaries were conducted daily. Both treatments induced the formation of an accessory corpus luteum and significantly increased the cross-sectional area of the luteal tissue when compared to the control. However, plasma progesterone (P4) was significantly higher in the treatment groups than in the control group on days 11, 12, 17 and 18 in the group 1 and from day 10 to 21 in the group 2. In Experiment 2, 41 cows were assigned to the same three groups described above and then artificially inseminated on day 1. The pregnancy rates on day 45 did not differ among groups. In conclusion, administration of GnRH analogue on day 6 following Ovsynch-based treatment did not improve the reproductive performance of Japanese black cows, even though the P4 concentration was higher in groups that received the GnRH.


Asunto(s)
Hormona Liberadora de Gonadotropina/farmacología , Reproducción/fisiología , Animales , Bovinos , Cuerpo Lúteo/anatomía & histología , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/fisiología , Preparaciones de Acción Retardada , Esquema de Medicación , Estro/efectos de los fármacos , Estro/fisiología , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Japón , Ovulación/efectos de los fármacos , Ovulación/fisiología , Placebos , Progesterona/sangre , Reproducción/efectos de los fármacos
3.
J Vet Sci ; 9(1): 95-101, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18303279

RESUMEN

The present experiment aims to examine the efficiency of estrus synchronization using progesterone and equine chorionic gonadotrophin (eCG) and to look at luteal function. During the non-breeding and breeding season, 5 adult female Korean native goats were injected intramuscularly with 2.5 ml of physiological saline as the control. A progesterone impregnated intravaginal sponge was then kept in the same goats for 10 days followed, after a week, by an intramuscular injection of 500 IU eCG. Five adult female Nubian goats were mated with a fertile buck during the non-breeding season. During the non-breeding season 2 of the 5 goats showed a normal estrous cycle (ranging from 18 to 21 days) and 3 a short estrous cycle (ranging from 3 to 6 days). During the breeding season the equivalent figures were 1 and 2. The major axes of the corpus luteum (CL) were measured by means of calipers built into the ultrasonography system, and the concentrations of plasma progesterone (P(4)) were determined by double antibody radioimmunoassay. The mean major axes of the CL in goats showing the short cycle (6.1 +/- 0.5 mm) was significantly smaller than in those showing the normal cycle (8.9 +/- 0.5 mm; p < 0.01) and also the value of P(4) in goats showing the short cycle (4.2 +/- 2.1 ng/ml) was significantly lower than for those showing the normal cycle (10.3 +/- 4.3 ng/ml; p < 0.05) at day 3 following ovulation. Three out of 5 Nubian goats became pregnant but only one goat carried to full term. The present experiment indicated that a combination of progesterone and eCG was effective in inducing estrus, although it resulted in a high incidence of short luteal lifespan. The low kidding rate and high incidence of embryonic loss may be due to the instability of the luteal lifespan.


Asunto(s)
Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/fisiología , Sincronización del Estro/efectos de los fármacos , Fertilidad/efectos de los fármacos , Cabras/fisiología , Progesterona/farmacología , Animales , Sincronización del Estro/fisiología , Femenino , Fármacos para la Fertilidad Femenina/farmacología , Caballos , Embarazo , Progesterona/sangre
4.
J Vet Med Sci ; 69(4): 429-32, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17485935

RESUMEN

The ovarian dynamics and uterine and ovarian blood flows of a 6-year-old (2 parturitions) Holstein Friesian cow with right uterine horn aplasia were observed during two estrous cycles. In one estrous cycle, a corpus luteum (CL) formed in the right ovary, but regression of the CL and subsequent ovulation were not observed. In the other estrous cycle, a CL formed in the left ovary and delayed regression of the CL and subsequent ovulation were observed. The blood velocity of the right uterine artery was lower than that of the left uterine artery throughout both estrous cycles when a CL formed in either the right and left ovary. The blood velocities of the right and left ovarian arteries were unaffected by right uterine horn aplasia and changed depending on the presence of a CL. These results indicated that the blood flow of the right uterine artery was very weak and that aplasia of one uterine horn affects the estrous cycle, especially CL regression.


Asunto(s)
Enfermedades de los Bovinos/patología , Ovario/irrigación sanguínea , Enfermedades Uterinas/veterinaria , Útero/irrigación sanguínea , Animales , Velocidad del Flujo Sanguíneo/veterinaria , Bovinos , Ciclo Estral , Femenino , Ovario/diagnóstico por imagen , Ultrasonografía Doppler en Color , Enfermedades Uterinas/patología , Útero/diagnóstico por imagen
5.
J Vet Med Sci ; 67(3): 275-80, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15805730

RESUMEN

Ovarian follicular dynamics and estrous synchronization after Gonadotropin-releasing hormone (GnRH) treatment at Controlled Internal Drug Releasing device (CIDR) insertion were investigated in Japanese Black cows. CIDR was inserted for eight cows at 7 days after estrus. Cows were allocated to either Group A: 8-day CIDR insertion with GnRH treatment on d 0 (n=4, d 0=CIDR insertion) or Group B: 8-day CIDR insertion (n=4). Both groups were injected with prostaglandin F2alpha (PGF2alpha) on d 7. Ultrasonography and blood sampling were performed twice daily. Intensive sampling was performed every 15 min for 8 hr to determine the pulsatile release of LH on d -1, d 5 and d 10. Three of four cows showed intermediate ovulation within 2 days after GnRH treatment during CIDR insertion in Group A, whereas no ovulation was found in Group B. Three of four cows in Group A and all four cows in Group B ovulated after CIDR removal. Plasma progesterone concentrations from d 3 to d 7 in three intermediate ovulatory cows in Group A (8.4 +/- 1.6 ng/ml) was significantly higher than those in Group B (4.1 +/- 1.2 ng/ml; 4 cows) during CIDR insertion (P<0.01). Interval to estrus and ovulation after CIDR removal was observed at 60.0 +/- 12.0 hr and 76.0 +/- 6.9 hr in three cows in Group A, and 75.0 +/- 15.1 hr and 93.0 +/- 20.5 hr in Group B, respectively. There was a significant increase in LH pulse frequency on d 10 compared on d -1 or d 5 in both groups (P<0.05), in addition those on d 10 in Group A tended to be higher than in Group B. As a result, GnRH treatment at CIDR insertion at 7 days after estrus induced intermediate ovulation with formation of corpus luteum (CL) and rather synchronized emergence of ovulatory follicle during CIDR insertion. These induced CL increased plasma progesterone concentrations and contributed to precise synchronization.


Asunto(s)
Bovinos/fisiología , Sincronización del Estro/efectos de los fármacos , Hormona Liberadora de Gonadotropina/farmacología , Folículo Ovárico/efectos de los fármacos , Animales , Bovinos/sangre , Cuerpo Lúteo/efectos de los fármacos , Preparaciones de Acción Retardada/farmacología , Dinoprost , Sincronización del Estro/fisiología , Femenino , Japón , Hormona Luteinizante/metabolismo , Folículo Ovárico/diagnóstico por imagen , Folículo Ovárico/fisiología , Ovulación/efectos de los fármacos , Progesterona/sangre , Radioinmunoensayo/veterinaria , Factores de Tiempo , Ultrasonografía
6.
J Vet Med Sci ; 66(12): 1497-502, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15644598

RESUMEN

Estrous synchronization using a Controlled Internal Drug Releasing device (CIDR) in combination with GnRH or estradiol benzoate (EB) treatment was investigated in Japanese black cows characterized with initial ovarian conditions. A total of 142 cows were allocated to one of four treatments: insertion of CIDR for eight days (Group A: n=34), CIDR with 100 microg of GnRH on d 0 (Group B: n=54, d 0=CIDR insertion), CIDR with GnRH on d 0 and 1 mg of EB on d 10 (Group C: n=20) or CIDR with 2 mg of EB on d 0 and 1 mg of EB on d 9 (Group D: n=34). All cows received 25 mg of PGF(2alpha) on d 7 and blood was collected for progesterone (P4) analysis on d 0, 8, and 21. AI was performed at estrus, but in Group D timed AI was set following a day of EB treatment. Estrus was induced in 141/142 cows, and the majority of which occurred on d 10 and 11 (98 cows, 34 cows). GnRH treatment induced more intermediate ovulation than EB treatment in cows with CL on d 0 (19.0% vs. 0%). Ovulation after CIDR removal was significantly higher in cows with CL on d 0 compared to those without CL (87.0% vs. 71.4%). Group B showed higher conception rates than those combined with Groups C and D where EB was injected after CIDR removal (51.1% vs. 38.9%). Conception had no correlation with either CL existence on d 0 or intermediate ovulation on d 8. P4 concentrations on d 8 were significantly lower compared to those on d 0 or d 21. On d 21 in cows without intermediate ovulation, Group A showed significantly lower P4 concentrations than the other 3 groups. The data suggests that CIDR insertion with PGF(2alpha) treatment is an effective method for estrous synchronization irrespective of initial ovarian conditions, and GnRH treatment at CIDR insertion induces intermediate ovulation and improves the conception rate in Japanese black cows.


Asunto(s)
Bovinos/fisiología , Estradiol/análogos & derivados , Estradiol/farmacología , Sincronización del Estro/métodos , Hormona Liberadora de Gonadotropina/farmacología , Inseminación Artificial/veterinaria , Progesterona/farmacología , Administración Intravaginal , Animales , Preparaciones de Acción Retardada , Relación Dosis-Respuesta a Droga , Sincronización del Estro/efectos de los fármacos , Femenino , Inseminación Artificial/métodos , Japón , Ovario/fisiología , Inducción de la Ovulación/veterinaria , Embarazo , Progesterona/administración & dosificación
7.
J Vet Med Sci ; 66(10): 1183-8, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15528846

RESUMEN

Distribution of estrogen receptor alpha (ERalpha) in the dominant follicle (DF) and corpus luteum (CL) at the three stages of estrous cycle in Japanese Black cows was evaluated by means of immunohistochemistry. Ovarian dynamics were observed twice daily using ultrasonography until the ovariectomy performed on Day 7 (First group, n=3), Day 10 (Second group, n=3) and Day 18 (Third group, n=3) (Day 0=estrus). Expression of ERalpha represented by immunohistological staining intensity in cells was determined using a light microscope equipped with a digital camera. A tendency toward higher expression were observed in theca interna (TI) of DF when compared with those in mural granulosa cells (mGC), antral granulosa cells (aGC) and theca externa (TE). ERalpha expression in the Third group was lower than that in the First Group in mGC, and it was also lower than that in the second group in TE (P<0.05). ERalpha expression in luteal cells was higher than those in the stromal cells in CL. No significant difference of ERalpha expression was observed within luteal or stromal cells, except in the Second group in the luteal cells, in which significantly higher expressions than that in the Third group (P<0.05) were observed. The results showed that, 1) ERalpha was present in developing DF on Day 7, early regressing DF on Day 10 and preovulatory DF on Day 18, especially in the TI, and a few were localized in the mGC, and 2) ERalpha was highly expressed in the luteal cells and the expression decreased in combination with regression of CL.


Asunto(s)
Bovinos/metabolismo , Cuerpo Lúteo/metabolismo , Receptor alfa de Estrógeno/metabolismo , Ciclo Estral/metabolismo , Folículo Ovárico/metabolismo , Análisis de Varianza , Animales , Femenino , Inmunohistoquímica , Japón , Factores de Tiempo
8.
J Vet Med Sci ; 66(1): 47-52, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14960810

RESUMEN

AIMS: To determine the turnover of the first follicular wave in Japanese black cows and quantitative immunohistological characteristics of the previously in vivo identified dominant follicle (DF) and largest subordinate follicle (SF) derived from ovariectomy on Day 7 (3 cows) and Day 10 (3 cows) (Day 0=estrus). Six cases of first follicular wave in cows were observed twice daily by ultrasound scanning. The number of follicles, diameter of DF and SF, and prevalence of apoptotic granulosa cells (GC) and theca cells (TC) were studied by TUNEL methods. At follicular wave emergence, 13.5 +/- 9.5 Class I (2-5 mm in diameter follicles) were found 12 hr after ovulation, and increased its number until Day 1 pm. Future DF and SF observed retrospectively were 4.9 +/- 0.8 mm and 4.9 +/- 0.9 mm at wave emergence. Deviation of DF and SF occurred on Day 3 pm with mean diameters of 8.9 +/- 1.3 mm and 6.8 +/- 0.9 mm, respectively. DF developed until Day 8 am with a maximum diameter of 14.4 +/- 1.8 mm (n=3) and then regressed. The follicular wall of the DF had a characteristic image of a healthy follicle on Day 7 and slightly atretic DF on Day 10, whereas SF showed heavy atresia on both Day 7 and Day 10 under HE staining. In the prevalence of apoptotic cells, DF were 4.4 +/- 1.0% and 17.9 +/- 4.9% on Day 7 and on Day 10 in GC, respectively, and 2.4 +/- 0.7% and 8.0 +/- 1.4% on Day 7 and on Day 10 in TC, respectively. These results showed that, 1) the first follicular wave in cows is characterized by 24 hr recruitment of small follicles and a gradual divergence of growth rates in future DF and SF, and 2) early regression of DF on Day 10 was preceded by severe apoptosis.


Asunto(s)
Folículo Ovárico/fisiología , Animales , Apoptosis , Bovinos , Dinoprost/farmacología , Estro/fisiología , Femenino , Células de la Granulosa/citología , Células de la Granulosa/fisiología , Japón , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Ovariectomía , Células Tecales/citología , Células Tecales/fisiología
9.
Vet Res ; 35(5): 531-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15369656

RESUMEN

To determine the teratogenic potential of Aino virus (AINOV) in cattle, pregnant cows and fetal cattle were infected with a fresh isolate of AINOV. Five pregnant cows were inoculated intravenously with the virus at 122 to 162 days of gestation and allowed to give birth. All of the cows developed neutralizing antibodies to the virus, indicating that the cows had been infected with the virus; however, no clinical abnormalities were seen in their six newborn calves, and no specific antibodies to the virus were detected in the precolostral serum of calves. Five fetuses with fetal ages ranging from 132 to 156 days were inoculated in utero with the virus. One weak newborn and four stillborn calves were delivered at gestation days 256 to 263, i.e., less than the standard gestation term; they had congenital abnormalities including arthrogryposis, hydranencephaly and cerebellar hypoplasia. Antibodies specific to AINOV were detected in their precolostral serum. These results demonstrate that AINOV is a potential etiological agent of congenital malformation of cattle.


Asunto(s)
Infecciones por Bunyaviridae/veterinaria , Bunyaviridae/patogenicidad , Enfermedades de los Bovinos/virología , Complicaciones Infecciosas del Embarazo/veterinaria , Anomalías Múltiples/veterinaria , Anencefalia/veterinaria , Animales , Anticuerpos Antivirales/análisis , Artrogriposis/veterinaria , Bunyaviridae/inmunología , Infecciones por Bunyaviridae/virología , Bovinos , Femenino , Hidranencefalia/veterinaria , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Síndrome
10.
Rev. cient. (Maracaibo) ; 16(4): 401-405, jul.-ago. 2006. tab, graf
Artículo en Inglés | LILACS | ID: lil-503952

RESUMEN

No se ha reportado adecuadamente el ambiente fisiológico del útero bovino a las limitaciones en la metodología. El objetivo del estudio fue medir la temperatura uterina bovina (UT) con un nuevo termómetro intracorporal (IC). Los datos fueron comparados con la temperaturra rectal (RT) y vaginal (VT) convencional. El IC es un dispositivo alojado dentro de un botón de acero limpio, con 15 mm de longitud, 5 mm de ancho, y con un rango de +15 a +46°C en 0,125 incrementos de °C. Se calibró con un termómetro de mercurio normal y también se puso en correlación con un termómetro rectal instalado con una sonda sensora de temperatura (0,1°C de precisión). UT era medida a intervalos de 20 min durante 4 semanas, mientras RT y VT eran medidas cada 4 h. Once vacas Negras Japonessas, 8 en el verano y 3 en el invierno, se sometieron a secciones de cesárea (CS). Por laparotomía trans-lumbar el IC se instaló en el cuerno uterino izquierdo próximo a la unión del uterotubarica. durante una Cs. Después de grabar durante 4 semanas, el CI fue removido con una 2da CS y el dispositivo se montó en el lector del mismo, en la PC. Los datos acuamulados se analizaron por ANOVA para mediciones repetidas. La temperatura ambiental (AT) se grabó simultáneamente. En 5 vacas, se colectó sangre, diariamente, para determinaciones hormonales (estradiol) y se realizó ultrasonografía para supervisar la dinámica ovárica. La temperatura después de la cirugía fue temporalmente elevada durante 4 días (0,14°C) y se excluyó. Los promedioas en UT, RT y VT en verano (AT: 28,76°C) fueron 38,57 ± 0.23°C , 38,67 ± 0,23°C, 38,60 ± 0,35°C, y en invierno (AT: 14,46°C) fueron 38,63 ± 0,21°C, 38,68 ± 0,21°C, 38,67 ± 0,20°C, respectivamente. UT fue significativamente baja que RT o VT, y UT en el verano fue más baja que en el invierno (P<0,01). Se observó el ritmo diurno en todas las tres temperaturas más bajo a las 08:00 y más alto a las 20:00 hs. En la ovulación, UT en la fase luteal...


Asunto(s)
Animales , Bovinos , Temperatura Corporal , Termómetros , Termómetros/veterinaria , Útero , Venezuela , Medicina Veterinaria
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