An overview on how cumulus cells interact with the oocyte in a condition with elevated NEFA levels in dairy cows

•Metabolic stress in human and animal is associated with impaired fertility.•Elevated levels of free fatty acids (NEFAs) in blood are a characteristic of metabolic stress.•Elevated NEFA levels in blood are reflected in follicular fluid.•Saturated NEFAs can have a detrimental impact on the competence of the oocyte to develop into an embryo.•Recent data shows that cumulus cells protect the oocyte against elevated levels of NEFAs.