GENETIC-EFFECTS ON FATTY-ACID COMPOSITION OF EGG-YOLK

Fatty acid (FA) composition was analysed in unincubated eggs of 200 he ns. The birds were either from lines (RIR, line 33, SS, line 44) and c rosses where feed efficiency of egg-mass production had been improved over eight to nine generations of reciprocal recurrent selection, or f rom a control population. The somewhat more efficient line 33 had less saturated FA (SAT FA), but a higher ratio for PUFA (polyunsaturated F A)/SAT. Selection decreased SAT FA but increased PUFA/SAT, and heteros is acted in the same direction. Thus it appears that modern poultry br eeding affects egg composition in a dietary desirable direction.