RESUMEN
Changes of progesterone (P4) profiles and oestrous cycle were investigated up to 70 days in 20 superovulated Holstein-Friesian cows in a dry tropical environment (Brazil). Superovulated cows showed no significant differences in relation to P4 level at the time of embryo recovery (39.0 +/- 27.1 nmol/L, P = 0.536), first and second (12.0 +/- 6.0 and 10.7 +/- 2.2 nmol/L, P = 0.543) cycle. There was a close correlation between serum P4 concentration and the number of corpora lutea (CL; 13.3 +/- 9.5) at the recovery (P < 0.0001). After the embryo collection, cows returned to cycle in different ways: (i) group of donors returning to cycle after 2.2 +/- 0.8 days, (ii) group with a delay of 11.0 +/- 1.9 days; and (iii) animals having a long (28.8 +/- 2.2 days) acyclic period, which is significant (P < 0.001). The remaining animals (30%) showed cystic ovarian malformations. P4 level at the time of embryo recovery does not influence the oestrous cycle changes. The results suggest that Holstein-Friesian donor cows may suffer from cystic ovarian degeneration and may have a long acyclic period after superovulatory treatment in a tropical climate.
Asunto(s)
Bovinos/fisiología , Estro/fisiología , Progesterona/sangre , Superovulación/fisiología , Adaptación Fisiológica , Animales , Brasil , Bovinos/sangre , Transferencia de Embrión/veterinaria , Estro/efectos de los fármacos , Femenino , Hormona Folículo Estimulante/uso terapéutico , Calor/efectos adversos , Reproducción/fisiología , Superovulación/efectos de los fármacos , Clima TropicalRESUMEN
Pregnant Holstein-Friesian (HF) heifers were transported from central Europe (defined as temperate conditions) to north-eastern Brazil (defined as tropical, semiarid conditions). They were kept in open-sided pens with a hard floor, a roof for shade and sprinkled with water for 10 min every hour if ambient temperature exceeded 30 degrees C. Their diet was balanced to meet nutritional requirements and they were fed twice daily. Control animals were randomly chosen first and second lactation animals located on a farm 25 km away and receiving similar management. Imported animals were superovulated in 1996 (n=63) and 1997 (n=96), compared to 38 and 45 cows in the control herd. The variates recorded were: the interval post-partum to first oestrus; changes in ovarian size and activity; responses to superovulation; and, embryo quality. The average daily milk yields of the imported cows were 20.0 and 23.3 l in 1996 and 1997, respectively compared to 22.1 l throughout the experiment for cows in the control herd. The post-partum anoestrus interval in the imported cows were 112.1+/-30.5 days in 1996 compared to 55.0+/-18.0, 48.2+/-12.0 and 42.6+/-10.7 days in 1997 for control cows. The size and functionality of the ovaries was lowest for the imported animals in 1996 but did not differ between other group-year combinations. These animals also had a lower superovulatory response in 1996 than control cows in terms of the number of ovulations (6.4+/-4.3 versus 13.6+/-5.9, P<0.05) and good quality embryos (1.2+/-0.9 versus 4.4+/-2.1, P<0.05). The two groups of cows did not differ in respect of these characters in the second year of the study. The imported cows had lower reproductive efficiency and responses to superovulation in their first year in their new environment. A period of approximately 1.5 years is required for full adaptation.
Asunto(s)
Adaptación Fisiológica/fisiología , Bovinos/fisiología , Clima , Preñez/fisiología , Superovulación/fisiología , Animales , Brasil , Estudios de Casos y Controles , Bovinos/embriología , Exposición a Riesgos Ambientales , Estro , Femenino , Embarazo , Reproducción/fisiología , Factores de TiempoRESUMEN
The results of a multiple ovulation and embryo transfer (MOET) program, obtained in its first two years, were evaluated. The donor heifers were imported already pregnant from Hungary to the North-East area of Brazil. Comparisons of the results obtained in 1996 and 1997 with superovulation programs with AUSA-Superov (FSH) and Folligon (eCG) were made. The number of CL found on both ovaries was 5.3 (FSH) and 4.2 (eCG) in 1996, and 8.2 (FSH) and 9.6 (eCG) in 1997, while the number of degenerated eggs and embryos was 2.8 (FSH) and 3.8 (eCG) in 1996, and 6.5 (FSH) and 7.4 (eCG) in 1997. The number of good quality embryos was 1.9 (FSH) and 2.3 (eCG) in 1996, and 5.5 (FSH) and 4.0 (eCG) in 1997. The embryo collection efficiency was 40% (FSH) and 35% (eCG) in 1996, and 85% (FSH) and 83% (eCG) in 1997. Significant differences were found for all results obtained in 1996 and 1997 (P 0.05). Two new commercial products were used in 1997, Pluset and Folltropin-V, both with FSHp. With Pluset therapy the number of unfertilized eggs and degenerated embryos harvested was 11.7 per retrieval, while the number of good quality embryos was 5.1 per retrieval. With Folltropin therapy the number was 4.5 and 1.9, respectively, showing that better results were obtained with Pluset (P 0.05).
Avaliou-se o desempenho de fêmeas bovinas doadoras de embrião nos primeiros dois anos de trabalho em um centro do programa multiple ovulation and embryo transfer (MOET). Utilizaram-se novilhas prenhes de recente importação de clima moderado para o Nordeste Brasileiro. Compararam-se os resultados de superovulação em 1996, primeiro ano de adaptação dos animais, e 1997 com AUSA-Superov (FSH) e Folligon (eCG). O número de CL contados no ovário foi 3,3 (FSH) e 4,2 (eCG) em 1996 e 8,2 (FSH) e 9,6 (eCG) em 1997, o de óvulos e embriões degenerados coletados de 2,8 (FSH) e 3,8 (eCG) em 1996 e 6,5 (FSH) e 7,4 (eCG) em 1997, o de embriões de boa qualidade de 1,9 (FSH) e 2,3 (eCG) em 1996 e 5,5 (FSH) e 4,0 (eCG) em 1997. A eficiência da coleta foi de 40% (FSH) e 35% (eCG) em 1996 e 85% (FSH) e 83% (eCG) em 1997. Todos os valores citados para 1996 e 1997 foram significativamente diferentes (P 0,05). Em 1997 foram utilizados dois produtos novos, Pluset e Folltropin-V, ambos à base de pFSH. Com Pluset o número de óvulos e embriões degenerados lavados foi de 11,7 unidades/doadora e o número de embriões de boa qualidade foi de 5,1 unidades/lavagem. Com Folltropin-V, o número foi de 4,5 unidades/lavagem e o de embriões viáveis de 1,9 unidades/doadora. Melhores resultados foram obtidos com Pluset (P 0,05).
RESUMEN
The results of a multiple ovulation and embryo transfer (MOET) program, obtained in its first two years, were evaluated. The donor heifers were imported already pregnant from Hungary to the North-East area of Brazil. Comparisons of the results obtained in 1996 and 1997 with superovulation programs with AUSA-Superov (FSH) and Folligon (eCG) were made. The number of CL found on both ovaries was 5.3 (FSH) and 4.2 (eCG) in 1996, and 8.2 (FSH) and 9.6 (eCG) in 1997, while the number of degenerated eggs and embryos was 2.8 (FSH) and 3.8 (eCG) in 1996, and 6.5 (FSH) and 7.4 (eCG) in 1997. The number of good quality embryos was 1.9 (FSH) and 2.3 (eCG) in 1996, and 5.5 (FSH) and 4.0 (eCG) in 1997. The embryo collection efficiency was 40% (FSH) and 35% (eCG) in 1996, and 85% (FSH) and 83% (eCG) in 1997. Significant differences were found for all results obtained in 1996 and 1997 (P 0.05). Two new commercial products were used in 1997, Pluset and Folltropin-V, both with FSHp. With Pluset therapy the number of unfertilized eggs and degenerated embryos harvested was 11.7 per retrieval, while the number of good quality embryos was 5.1 per retrieval. With Folltropin therapy the number was 4.5 and 1.9, respectively, showing that better results were obtained with Pluset (P 0.05).
Avaliou-se o desempenho de fêmeas bovinas doadoras de embrião nos primeiros dois anos de trabalho em um centro do programa multiple ovulation and embryo transfer (MOET). Utilizaram-se novilhas prenhes de recente importação de clima moderado para o Nordeste Brasileiro. Compararam-se os resultados de superovulação em 1996, primeiro ano de adaptação dos animais, e 1997 com AUSA-Superov (FSH) e Folligon (eCG). O número de CL contados no ovário foi 3,3 (FSH) e 4,2 (eCG) em 1996 e 8,2 (FSH) e 9,6 (eCG) em 1997, o de óvulos e embriões degenerados coletados de 2,8 (FSH) e 3,8 (eCG) em 1996 e 6,5 (FSH) e 7,4 (eCG) em 1997, o de embriões de boa qualidade de 1,9 (FSH) e 2,3 (eCG) em 1996 e 5,5 (FSH) e 4,0 (eCG) em 1997. A eficiência da coleta foi de 40% (FSH) e 35% (eCG) em 1996 e 85% (FSH) e 83% (eCG) em 1997. Todos os valores citados para 1996 e 1997 foram significativamente diferentes (P 0,05). Em 1997 foram utilizados dois produtos novos, Pluset e Folltropin-V, ambos à base de pFSH. Com Pluset o número de óvulos e embriões degenerados lavados foi de 11,7 unidades/doadora e o número de embriões de boa qualidade foi de 5,1 unidades/lavagem. Com Folltropin-V, o número foi de 4,5 unidades/lavagem e o de embriões viáveis de 1,9 unidades/doadora. Melhores resultados foram obtidos com Pluset (P 0,05).