Eficiência reprodutiva de vacas Nelore submetidas à IATF com protocolos DIB® e Crestar® e suas variações / Reproductive efficiency of Nelore cows submitted to FTAI with DIB® and Crestar® protocols and their variations

The economic efficacy of beef cattle is linked to the production of calves, which are destined to the meatproduction or replacement of the herd. Therefore the reproductive efficiency of the bovine females is shown to beof great importance, mainly in relation to occurrence of the gestations at certain moments during thereproductive season. Fixed Time Artificial Insemination (FTAI) is a biotechnology that optimizes thereproductive management and guarantees satisfactory results. In this context, this research aimed to evaluateovulation synchronization protocols (Crestar®, DIB® and variations) used in breeding season, verifying thereproductive efficiency of Nelore cows submitted to FTAI. The results obtained from the FTAI program arewithin the predicted average, in which cows submitted to the DIB + BE protocol, used in the latter group,showed the best result, with a mean of 55.8% conception rate, being considered the most satisfactory within the four protocols used.(AU)

Reprodução e critérios de seleção de ovinos machos e fêmeas em programas de melhoramento genético na ilha de São Luís MA / Breeding and selection criteria for male and female sheeps in genetic enhancement programs in São Luís Ma

This study aimed to characterize the selection criterion for sheep, male and female, most applied infarms located in the municipalities that make up the micro region urban agglomeration of São Luís, Maranhão.Technical visits were performed in 10 properties where, in each, a questionnaire and information related to thecreation of system was applied, purpose of creation, breeds, selection criterion and availability of geneticresources were obtained. The most valued characteristics to select the parents, regardless of their race, allproperties were observing the animal phenotype, with no use of genetic resources for the practice, and thesecriterion related to body development (100%) for both sex, scrotal circumference and volume (100%), testiculartilting (20%) for males, and sexual precocity, maternal ability and number of calving (40%) for females.(AU)

Eficiência reprodutiva de vacas Nelore submetidas à IATF com protocolos DIB® e Crestar® e suas variações / Reproductive efficiency of Nelore cows submitted to FTAI with DIB® and Crestar® protocols and their variations

The economic efficacy of beef cattle is linked to the production of calves, which are destined to the meatproduction or replacement of the herd. Therefore the reproductive efficiency of the bovine females is shown to beof great importance, mainly in relation to occurrence of the gestations at certain moments during thereproductive season. Fixed Time Artificial Insemination (FTAI) is a biotechnology that optimizes thereproductive management and guarantees satisfactory results. In this context, this research aimed to evaluateovulation synchronization protocols (Crestar®, DIB® and variations) used in breeding season, verifying thereproductive efficiency of Nelore cows submitted to FTAI. The results obtained from the FTAI program arewithin the predicted average, in which cows submitted to the DIB + BE protocol, used in the latter group,showed the best result, with a mean of 55.8% conception rate, being considered the most satisfactory within the four protocols used.

Reprodução e critérios de seleção de ovinos machos e fêmeas em programas de melhoramento genético na ilha de São Luís – MA / Breeding and selection criteria for male and female sheeps in genetic enhancement programs in São Luís – Ma

This study aimed to characterize the selection criterion for sheep, male and female, most applied infarms located in the municipalities that make up the micro region urban agglomeration of São Luís, Maranhão.Technical visits were performed in 10 properties where, in each, a questionnaire and information related to thecreation of system was applied, purpose of creation, breeds, selection criterion and availability of geneticresources were obtained. The most valued characteristics to select the parents, regardless of their race, allproperties were observing the animal phenotype, with no use of genetic resources for the practice, and thesecriterion related to body development (100%) for both sex, scrotal circumference and volume (100%), testiculartilting (20%) for males, and sexual precocity, maternal ability and number of calving (40%) for females.