Cultural strategies for maturation of carnivore oocytes

Feline and canine oocytes are characterized by unique features and consequently in vitro conditions for maturation differ from other mammalian models. However, the attempt to create a microenvironment similar to that in which oocyte development occurs physiologically is challenging in these species, since little is known on mechanisms regulating oocyte maturation. In vivo, the acquisition of oocyte competence occurs in the follicular and in the oviductal environments and an in vitro maturation system should support the dynamic changes related to nuclear and cytoplasmic maturation occurring to all components of the cumulus-oocyte complex. Modifications of the cultural environment during maturation, by addition of substances that stimulate endogenous systems of cell defence and modulate the intracellular levels of regulatory molecules, or by use of sequential different culture systems, may be interesting strategies for enhancing viability and competence of the Carnivore oocytes.