Efeito do protocolo de pré-sincronização em vacas mestiças no período pós-parto.

• Autor(a) principal: Almeida, Ítalo Câmara de
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/7753
• topic: Estradiol; Progesterone; TAI; Estradiol; IATF; Progesterona; Ciências Agrárias; 619

This study aimed to evaluate the efficiency of the pre - synchronization hormonal protocol based in progesterone and estradiol in crossbred cows, milch , lactating , primiparous and multiparous , in early postpartum, regarding the follicular dynamics and reproductive efficiency . It were used 9 2 cows from 30 to 90 days postpartum, which were randomly allocated to two experimental groups, control ( CG ) and treatment ( TG ). In the control group , animals were subject only to time - fixed artificial insemination protocol ( TAI ), and TG animals were submi tted to a hormonal protocol for pre - synchronization before TAI . For the CG it were used 45 cows, in which 6 were used for analysis of follicular dynamics and 39 to evaluate the reproductive efficiency, and followed that up with the hormonal protocol: on da y zero (D0): insertion of intravaginal progesterone device (DIV P 4 ) new and intramuscular injection (IM) of 2 mg estradiol benzoate (EB); D8: removal of DIV P 4 IM , administration of 300 IU of equine chorionic gonadotropin (eCG) and IM administration of 0 , 15 mg of sodium cloprostenol (prostaglandin); D9: IM application of 1 mg of EB and; D10: TAI of the animals. For the TG it were used 47 cows, 8 of them for analysis of follicular dynamics and 39 to detect the pregnancy rate, and followed that up with the ho rmonal protocol of hormonal pre - synchronization: Day least nineteen (D - 19): inserting DIV P 4 previously used ( 4 th use) and IM administration of 2 mg of EB; D - 11: removal of DIV P 4 and IM application of 1 mg BE; elapsed 11 days from the withdrawal of DIV P 4 previously used, it began the protocol for T AI of animals with identical protocol to that used for the CG . The ultrasound exam s r egarding the follicular dynamics were performed on days 0, 8 and starting from the day of TAI (D10) in every 12 hours until t he determination of ovulation by the absence of the dominant follicle. After 30 days of TAI , it was estimated the pregnancy rate by ultrasound examination. Data were analyzed using SAS statistical program, considering the 5% critical probability. There was no significant difference (P ? 0 , 05) in the mean number of follicles on days 0, 8 and 10 between treatments. There was no significant difference (p ? 0 , 05) for follicular growth rate, which was 1 , 8 ± 0 , 24 and 0 , 79 ± 0 , 35 mm / day for the TG and CG groups, respectively. There was no effec t of treatment (P ? 0 , 05) to the diameter of the dominant follicle at the moment of T AI, and 12 , 5 ± 1 , 61 mm for the treatment group and 11 , 9 ± 2 , 26 mm for the control group. There were no effects of treatments (P ? 0.05) on the interval between the removal of proges terone device and ovulation of TG (65h25min ± 8h13min) and CG (66h ± 10h03min), and also of ovulation TAI, which was 14h1 5min ± 7 h 36min and 15 h 0 6min ± 9 h 0 4min for TG and CG groups, respectively. There were not effects of treatments (P ? 0.05) on the ra te of ovulation and pregnancy, which was 88 , 8% and 53 , 84%, respectively for the TG and 75% and 38 , 46%, respectively for the CG . There was a significant difference (P? 0.05) in pregnancy rate between primiparous cows (23.07%) and multiparous (69.23%) for the TG . It is concluded that the use of pre - synchronization protocol in crossbred cows in the early postpartum showed no marked differences in the evaluated patterns. Multiparous cows had higher pregnancy rate primiparous cows. The pregnancy rate of pre - synch ronization group of cows was satisfactory, above 50% for TAI protocols