Abortive Spontaneous Egg Activation: An Emerging Biological Threat for the Existence of Mammals.

Mammals are important for balancing the natural ecosystem, but in the past few decades, several species have rapidly been entered under threatened category worldwide. The environmental changes, loss of natural habitats, human activities, and thereby stress are responsible for a gradual decline in reproductive outcome. Stress induces generation of reactive oxygen species (ROS). High physiological level of ROS drives abortive spontaneous egg activation (SEA), while beyond the physiological level causes oxidative stress (OS). The OS induces apoptosis and deteriorates egg quality that limits reproductive outcome. The reduced reproductive outcome is one of the major causes for gradual decline in population size of several mammalian species. Despite having several conservation programs, a gradual decline in species reproductive outcome and their population size is the serious concern for the existence of threatened mammalian species. Thus, it is important to identify and prevent the underlying causes responsible for abortive SEA, which could be an emerging problem for several mammalian species that are threatened or at the verge of extinction.