Efeito do uso de eCG em protocolo de inseminação artificial em tempo fixo em vacas mestiças leiteiras / Effect of using eCG in the fixed-time artificial insemination protocol in mixed-race dairy cows

No Brasil, cerca de 5% do rebanho bovino é reproduzido através da biotecnologia de inseminação artificial (IA). O sucesso da IA depende de fatores inerentes à fêmea, ao sêmen e a habilidade do inseminador. Dentre os fatores inerentes a fêmea destaca-se: escore corporal, estado sanitário, estado reprodutivo e protocolo hormonal utilizado. A literatura relata diferentes resultados entre os diversos protocolos hormonais. Desta forma, este trabalho teve por objetivo verificar a eficácia do uso do eCG em protocolos de inseminação artificial em tempo fixo (IATF) em bovinos. Foram utilizadas vacas mestiças Girolando (n=4886), com peso médio de 500kg, as quais foram divididas em dois grupos, IATF 1 (n=2,535) e IATF 2 (n=2,351). Os dados das amostras foram coletados dasUnidades Produtoras de Leite (UPLs), as quais fazem parte do complexo leiteiro da Fazenda. As vacas foram divididas em dois grupos, IATF 1 e IATF 2 a cada trimestre. Ambos os protocolos de IATF foram realizados durante um período de dez dias. No dia 0 foi administrado o implante intrauterino impregnado com progesterona (1g), o qual permaneceu durante oito dias e administrado 2 mL de Benzoato de Estradiol pela via intramuscular. Após a remoção do implante no D8, administrou-se por via intramuscular 2 mL de prostaglandina F2α (PGF2α) juntamente com 1 mL de Cipionato de Estradiol. Nas fêmeas IATF 1 com folículos menos desenvolvidos aplicou-se 2 mL de gonadrotofina coriônica equina (eCG) por via intramuscular. Concluiu-se que a utilização de eCG elevou as taxas de fertilização em vacas com folículos menores, porém foi desnecessário para as fêmeas que apresentaram condições uterinas normais.

In Brazil, about 5% of the cattle herd reproduces through artificial insemination (AI) biotechnology. The success of AI depends on factors inherent to the female, inherent to the semen and the inseminator's ability. Among the factors inherent to the female are: body score, health status, reproductive status and hormonal protocol used. The literature reports different results among the various hormonal protocols. Therefore, the objective of this study was to verify the efficacy of eCG in fixed-time artificial insemination (IATF) protocols in cattle. Girolando crossbred cows (n=4886), with an average weight of 500 kg, were divided into two groups, IATF 1 (n=2.535) and IATF 2 (n=2.351). The data of the samples were collected from the Milk Producing Units (UPLs) - Campo Grande, Colmalândia, Ouro Branco and Ouro Verde - that are part of Fazenda dairy complex. Cows were divided into two groups, IATF 1 and IATF 2 each quarter. Both IATF protocols were performed over a ten day period. On day 0, the progesterone-impregnated intrauterine implant (1g) was administered, which remained for eight days and administered 2 mL of Estradiol Benzoate intramuscular. After removal of the implant in the D8, 2 mL of prostaglandin F2α (PGF2α) were administered intramuscularly together with 1 mL of Estradiol Cypionate. It was concluded that the use of eCG increased fertilization rates in cows with smaller follicles, but was unnecessary for females that presented normal uterine conditions.

Efeito do uso de eCG em protocolo de inseminação artificial em tempo fixo em vacas mestiças leiteiras / Effect of using eCG in the fixed-time artificial insemination protocol in mixed-race dairy cows

No Brasil, cerca de 5% do rebanho bovino é reproduzido através da biotecnologia de inseminação artificial (IA). O sucesso da IA depende de fatores inerentes à fêmea, ao sêmen e a habilidade do inseminador. Dentre os fatores inerentes a fêmea destaca-se: escore corporal, estado sanitário, estado reprodutivo e protocolo hormonal utilizado. A literatura relata diferentes resultados entre os diversos protocolos hormonais. Desta forma, este trabalho teve por objetivo verificar a eficácia do uso do eCG em protocolos de inseminação artificial em tempo fixo (IATF) em bovinos. Foram utilizadas vacas mestiças Girolando (n=4886), com peso médio de 500kg, as quais foram divididas em dois grupos, IATF 1 (n=2,535) e IATF 2 (n=2,351). Os dados das amostras foram coletados dasUnidades Produtoras de Leite (UPLs), as quais fazem parte do complexo leiteiro da Fazenda. As vacas foram divididas em dois grupos, IATF 1 e IATF 2 a cada trimestre. Ambos os protocolos de IATF foram realizados durante um período de dez dias. No dia 0 foi administrado o implante intrauterino impregnado com progesterona (1g), o qual permaneceu durante oito dias e administrado 2 mL de Benzoato de Estradiol pela via intramuscular. Após a remoção do implante no D8, administrou-se por via intramuscular 2 mL de prostaglandina F2α (PGF2α) juntamente com 1 mL de Cipionato de Estradiol. Nas fêmeas IATF 1 com folículos menos desenvolvidos aplicou-se 2 mL de gonadrotofina coriônica equina (eCG) por via intramuscular. Concluiu-se que a utilização de eCG elevou as taxas de fertilização em vacas com folículos menores, porém foi desnecessário para as fêmeas que apresentaram condições uterinas normais.(AU)

In Brazil, about 5% of the cattle herd reproduces through artificial insemination (AI) biotechnology. The success of AI depends on factors inherent to the female, inherent to the semen and the inseminator's ability. Among the factors inherent to the female are: body score, health status, reproductive status and hormonal protocol used. The literature reports different results among the various hormonal protocols. Therefore, the objective of this study was to verify the efficacy of eCG in fixed-time artificial insemination (IATF) protocols in cattle. Girolando crossbred cows (n=4886), with an average weight of 500 kg, were divided into two groups, IATF 1 (n=2.535) and IATF 2 (n=2.351). The data of the samples were collected from the Milk Producing Units (UPLs) - Campo Grande, Colmalândia, Ouro Branco and Ouro Verde - that are part of Fazenda dairy complex. Cows were divided into two groups, IATF 1 and IATF 2 each quarter. Both IATF protocols were performed over a ten day period. On day 0, the progesterone-impregnated intrauterine implant (1g) was administered, which remained for eight days and administered 2 mL of Estradiol Benzoate intramuscular. After removal of the implant in the D8, 2 mL of prostaglandin F2α (PGF2α) were administered intramuscularly together with 1 mL of Estradiol Cypionate. It was concluded that the use of eCG increased fertilization rates in cows with smaller follicles, but was unnecessary for females that presented normal uterine conditions.(AU)

Taxa de prenhez em vacas leiteiras submetidas a inseminação artificial em tempo fixo utilizando gonadotrofina coriônica equin / Pregnancy rate in dairy cows submitted to fixed time artificial insemination using equine chorionic gonadotropin

This study aimed to evaluate the pregnancy rate in cyclic lactating dairy cows inseminated at fixed timeusing eCG in the withdrawal of progesterone implant. The experimental design was a randomized blocks, twotreatments with 32 repetitions for G1 and 31 repetitions for G2. The G1 control group: cows with hormonalprotocol with the use of eCG; G2: cows with hormonal protocol without using eCG. The study presented to theGroup eCG with pregnancy rate of 28.13%, while no eCG group had a 16.13% pregnancy rate. The statisticaldifference between the groups was not significant (p = 0.2522). In conclusion, the use of eCG had no influenceon the pregnancy rate.(AU)

Taxa de prenhez em vacas leiteiras submetidas a inseminação artificial em tempo fixo utilizando gonadotrofina coriônica equin / Pregnancy rate in dairy cows submitted to fixed time artificial insemination using equine chorionic gonadotropin

This study aimed to evaluate the pregnancy rate in cyclic lactating dairy cows inseminated at fixed timeusing eCG in the withdrawal of progesterone implant. The experimental design was a randomized blocks, twotreatments with 32 repetitions for G1 and 31 repetitions for G2. The G1 control group: cows with hormonalprotocol with the use of eCG; G2: cows with hormonal protocol without using eCG. The study presented to theGroup eCG with pregnancy rate of 28.13%, while no eCG group had a 16.13% pregnancy rate. The statisticaldifference between the groups was not significant (p = 0.2522). In conclusion, the use of eCG had no influenceon the pregnancy rate.