Encapsulation of micromanipulated mammalian embryos

Micromanipulation of gametes is one of the reproductive biotechnologies that have an obvious contribution to animal production, human welfare, industry and research. The current reproductive techniques that employ micromanipulation are chimerism, embryo bisection, intracytoplasmic sperm injection (ICSI), gene injection and nuclear transfer (the so cold cloning). In all these techniques it is necessary to perforate, slit or even to remove zona pellucida (ZP). The ZP is a glycoprotein layer that protects embryos not only from predators but also protects them from toxic substances in culture media and/or uterine environment. This article summarized the influences of micromanipulation and encapsulation with artificial ZP (AZP) made of sodium alginate on in vitro development of micromanipulated embryos. The article also described how embryos with defective ZP (DZP) could be microencapsulated with an AZP.