A responsabilidade por danos ocasionados ao meio ambiente e a atividade de mineração: o desastre ocorrido em Mariana – MG / The responsibility for damage to the environment and the mining activity: the disaster occurred in Mariana – MG

O presente trabalho analisa a proteção ao meio ambiente pelo ordenamento jurídico brasileiro. Identifica, desde a Constituição Federal, até a legislação infraconstitucional, dispositivos que tratam da proteção ao meio ambiente e da responsabilidade daqueles que causarem dano ambiental em indenizar e reparar os prejuízos. Ao final, relaciona a responsabilidade jurídica prevista pela legislação ao caso específico do acidente ambiental ocorrido em Mariana, Minas Gerais, no ano de 2015.

This paper analyzes the protection of the environment by the Brazilian legal system. It identifies, from the Federal Constitution, to the infraconstitutional legislation, devices that deal with the protection of the environment and the responsibility of those who cause environmental damages in indemnifying and repairing the damages. In the end, it relates the legal responsibility provided by the legislation to the specific case of the environmental accident occurred in Mariana, Minas Gerais, in the year 2015.

A responsabilidade por danos ocasionados ao meio ambiente e a atividade de mineração: o desastre ocorrido em Mariana MG / The responsibility for damage to the environment and the mining activity: the disaster occurred in Mariana MG

O presente trabalho analisa a proteção ao meio ambiente pelo ordenamento jurídico brasileiro. Identifica, desde a Constituição Federal, até a legislação infraconstitucional, dispositivos que tratam da proteção ao meio ambiente e da responsabilidade daqueles que causarem dano ambiental em indenizar e reparar os prejuízos. Ao final, relaciona a responsabilidade jurídica prevista pela legislação ao caso específico do acidente ambiental ocorrido em Mariana, Minas Gerais, no ano de 2015.(AU)

This paper analyzes the protection of the environment by the Brazilian legal system. It identifies, from the Federal Constitution, to the infraconstitutional legislation, devices that deal with the protection of the environment and the responsibility of those who cause environmental damages in indemnifying and repairing the damages. In the end, it relates the legal responsibility provided by the legislation to the specific case of the environmental accident occurred in Mariana, Minas Gerais, in the year 2015.(AU)

Factors that interfere with oocyte quality for in vitro production of cattle embryos: effects of different developmental & reproductive stages

The success of IVP is ultimately dependent on the number and quality of the cumulus-oocyte complexes (COC) harvested during the OPU procedure. Several factors appear to be critical to oocyte quality including follicle size, environment factors such as heatstress, genetic background, age and lactation status of donor animals, all having a remarkable influence on the results of IVP. The aim of this review is to highlight some critical areas that can help veterinary practitioners to enhance OPU efficiency and successfully implement IVP into their routine practice. Focus will be given to recent findings in the literature and underlying physiological aspects that may be interfering with the quality of oocytes addressed to IVP in cattle at younger ages (calves and prepubertal heifers), pregnant vs nonpregnant status, and possible interactions with lactation and days postpartum during OPU.

Factors that interfere with oocyte quality for in vitro production of cattle embryos: effects of different developmental & reproductive stages

The success of IVP is ultimately dependent on the number and quality of the cumulus-oocyte complexes (COC) harvested during the OPU procedure. Several factors appear to be critical to oocyte quality including follicle size, environment factors such as heatstress, genetic background, age and lactation status of donor animals, all having a remarkable influence on the results of IVP. The aim of this review is to highlight some critical areas that can help veterinary practitioners to enhance OPU efficiency and successfully implement IVP into their routine practice. Focus will be given to recent findings in the literature and underlying physiological aspects that may be interfering with the quality of oocytes addressed to IVP in cattle at younger ages (calves and prepubertal heifers), pregnant vs nonpregnant status, and possible interactions with lactation and days postpartum during OPU.(AU)

Updates on embryo production strategies

The embryo production technologies are used to enhance genetic progress through female and male lineages. Advances in the control of ovarian follicular wave emergence, superstimulation and ovulation with self-appointed treatments have facilitated donor and recipient management. However, these procedures can be influenced by several factors related to the animals and their management. Therefore, researchers continue to investigate the ideal reproductive environments and treatments to maintain the viability of the techniques and field applicability.(AU)

Updates on embryo production strategies

The embryo production technologies are used to enhance genetic progress through female and male lineages. Advances in the control of ovarian follicular wave emergence, superstimulation and ovulation with self-appointed treatments have facilitated donor and recipient management. However, these procedures can be influenced by several factors related to the animals and their management. Therefore, researchers continue to investigate the ideal reproductive environments and treatments to maintain the viability of the techniques and field applicability.

Strategies to increase in vitro embryo yield: lessons from cell and mocelular research

Numerous reproductive biotechnologies are commonly employed to enhance animal production mainly through multiplying animals with high-quality traits in a large-scale production system. There is however, several peculiarities during the process of embryo in vitro production that are still in need of further studies in order to obtain a higher efficiency. This present review discuss some of such particularities, as well as new models of embryo and gamete production, which will probably be part of a new era of reproductive biotechnologies in a near future.

Strategies to increase in vitro embryo yield: lessons from cell and mocelular research

Numerous reproductive biotechnologies are commonly employed to enhance animal production mainly through multiplying animals with high-quality traits in a large-scale production system. There is however, several peculiarities during the process of embryo in vitro production that are still in need of further studies in order to obtain a higher efficiency. This present review discuss some of such particularities, as well as new models of embryo and gamete production, which will probably be part of a new era of reproductive biotechnologies in a near future.(AU)

Controle do crescimento e da seleção folicular por fatores locais e sistêmicos na espécie bovina / Local and systemic control of bovine follicular growth and selection

A regulação da atividade ovariana é um processo integrado que envolve sinalização extraovariana e fatores intrafoliculares. Todavia, o real fator desencadeador do processo de seleção folicular ainda parece obscuro. As gonadotrofinas possuem papel importante, mas nem sempre fundamental. A ativação do folículo primordial e os estágios iniciais da foliculogênese podem ocorrer na ausência de gonadotrofinas, no entanto o FSH pode afetar a taxa de crescimento do folículo pré-antral. Já o desenvolvimento do folículo antral de 1 para 4 mm de diâmetro é completamente dependente de gonadotrofinas em bovinos, e a transferência de dependência de FSH para LH pode fazer parte do mecanismo de seleção folicular. Além disso, fatores de crescimento locais, como o sistema IGF, atuam em associação com as gonadotrofinas durante o crescimento folicular, podendo também influenciar o processo de seleção do folículo dominante. Portanto, a integração de sinais extraovarianos e de fatores intrafoliculares irá determinar se um folículo continuará seu desenvolvimento ou entrará em atresia. Essa revisão foca-se na interação entre as gonadotrofinas e os fatores intrafoliculares no desenvolvimento e na seleção folicular em bovinos.(AU)

The regulation of ovarian activity is an integrated process involving extraovarian signals and intrafollicular factors. In such process, gonadotropins have an important role, but not always crucial. The initiation of primordial follicle growth and the early stages of folliculogenesis can occur without gonadotropins, however FSH may affect the rate of preantral follicle growth. On the other hand, the antral follicle development from 1 to 4 mm in diameter is completely gonadotropin-dependent in bovine, and the alternation of dependency from FSH to LH may be part of the mechanism involved in follicular selection. Locally produced growth factors, such as the IGF system, work in association with gonadotropins throughout the follicular growth and can influence follicular selection. Thus, the integration of these extraovarian signals and intrafollicular factors seems to determine whether a follicle will continue to develop or go atretic. This review focuses on the interaction between gonadotropins and intrafollicular factors in follicular development and selection in cattle.(AU)

Controle do crescimento e da seleção folicular por fatores locais e sistêmicos na espécie bovina / Local and systemic control of bovine follicular growth and selection

A regulação da atividade ovariana é um processo integrado que envolve sinalização extraovariana e fatores intrafoliculares. Todavia, o real fator desencadeador do processo de seleção folicular ainda parece obscuro. As gonadotrofinas possuem papel importante, mas nem sempre fundamental. A ativação do folículo primordial e os estágios iniciais da foliculogênese podem ocorrer na ausência de gonadotrofinas, no entanto o FSH pode afetar a taxa de crescimento do folículo pré-antral. Já o desenvolvimento do folículo antral de 1 para 4 mm de diâmetro é completamente dependente de gonadotrofinas em bovinos, e a transferência de dependência de FSH para LH pode fazer parte do mecanismo de seleção folicular. Além disso, fatores de crescimento locais, como o sistema IGF, atuam em associação com as gonadotrofinas durante o crescimento folicular, podendo também influenciar o processo de seleção do folículo dominante. Portanto, a integração de sinais extraovarianos e de fatores intrafoliculares irá determinar se um folículo continuará seu desenvolvimento ou entrará em atresia. Essa revisão foca-se na interação entre as gonadotrofinas e os fatores intrafoliculares no desenvolvimento e na seleção folicular em bovinos.

The regulation of ovarian activity is an integrated process involving extraovarian signals and intrafollicular factors. In such process, gonadotropins have an important role, but not always crucial. The initiation of primordial follicle growth and the early stages of folliculogenesis can occur without gonadotropins, however FSH may affect the rate of preantral follicle growth. On the other hand, the antral follicle development from 1 to 4 mm in diameter is completely gonadotropin-dependent in bovine, and the alternation of dependency from FSH to LH may be part of the mechanism involved in follicular selection. Locally produced growth factors, such as the IGF system, work in association with gonadotropins throughout the follicular growth and can influence follicular selection. Thus, the integration of these extraovarian signals and intrafollicular factors seems to determine whether a follicle will continue to develop or go atretic. This review focuses on the interaction between gonadotropins and intrafollicular factors in follicular development and selection in cattle.