[Essential fatty acids and animal development].

With the exception of some cell strains in culture, the animal cells need w6 linoleic acid and its superior polyinsaturated derivatives for their structural growth and their multiplication. Deficiency of linoleic acid leads to growth failure, organic fraility and death of the animal. Involvement of the prostaglandins is not demonstrated. w3 linolenic acid and its superior derivatives are essential for the development of the sea animals. Linolenic acid appears also essential for the mammal nervous cells at the step of cell division anterior to myelinisation. Disponibility of the essential fatty acids for the mammal fetus is principaly assumed by the mother liver of which the metabolic activity in conversion of the precursors to superior derivatives and synthesis of transport lipoproteins is increased. Involvement of the polyunsatured acids in satisfying the structural and energetic needs of the developing animal concerns predominantly--but not exclusively--the cell membranes structure and fluidity and activity of the functional proteins (enzymes, mitochondrial oxydophosphorylation).