F,I Chem. Toxic. Vol. 20. pp. 153 to 157. 1982 0278-6915/82/020153-05S03.00/0 Printed in Great Britain. All rights reserved Copyright O 1982 Pergamon Press Ltd Research Section EFFECTS OF DIETARY PHOSPHOLIPIDS AND ODD-CHAIN FATTY ACIDS ON THE BEHAVIOURAL MATURATION OF MICE S. Gozzo and A. OLIVERIO* lstituto di Psicobiologia e Psicofarmacologia, CNR, via Reno 1, 00198 Rome, and lstituto di Fisiologia Generale, University of Rome S. SALVATIand G. SERLUPI-CRESCENZI Istituto Superiore di SanitY, Rome and B. TAGLIAMONTE and G. TOMASSI Istituto Nazionale della Nutrizione, Rome, Italy (Received 24 November 198tk revision received 21 October 1981) Abstract--Five groups of female mice were fed from day 14 of pregnancy and throughout lactation on synthetic diets differing only in the lipid component, which constituted 10~ of the diet and was derived from (a) the lipid fraction extracted from yeast grown on n-alkanes, (b) commercial soya lecithin, (c) fatty acids isolated from yeast lipids (odd-chain fatty acids), (d) lipids extracted from yeast grown on glucose or (e) margarine {8~), corn oil (1~) and the unsaponifiable fraction (l~) from yeast grown on n-alkanes. A control diet (9~o margarine and I~ corn oil) was fed to a sixth group of pregnant mice and to the offspring of all the groups from weaning to 60 days after birth. A battery of behavioural tests was performed on the offspring of the six groups between days 1 and 16 after birth (reflex activities), between days 2 and 21 (locomotor activity) and at 60 days of age (avoidance learning). An acceleration of postnatal behavioural maturation was evident in the pups of animals fed lipids from yeast grown on n-alkanes and of those fed soya lecithin, indicating the involvement of phospholipids and odd-chain fatty acids in the aspects of development studied. INTRODUCTION Toxicological evaluation of new food sources presents great difficulties because the administration of large doses leads to side effects due to nutritional imbalance. Yeast biomasses containing more than 109/o of lipids of unusual composition--75~ phospholipids with over 50~o odd-chain fatty acids (Bernardini, Boniforti, Merli & Mosuri, 1975)---can be assessed for safety by isolating the lipid fraction from the biomass itself, as suggested by Friedman, Glaser, Brown & Pariser (1971). Using this method, behavioural abnor- malities were observed in rats (Gozzo, Oliverio, Sal- vati et al. 1978), in spite of the fact that odd-chain fatty acids seemed to be metabolized and incorpor- ated normally into various tissues (Bernardini, Sal- vati, Serlupi-Crescenzi et al. 1978b,c) without affecting functional capacity (Bernardini, Salvati & Serlupi- Crescenzi, 1978a). *To whom correspondence should be addressed (at the Istituto di Psicobiologia e Psicofarmacologia). ~Registered trade name of British Petroleum Co. Ltd. Abbreviations: Diets--C/A = Candida on alkanes, C/G = Candida on glucose, OFA = odd-chain fatty acids, SL = soya lecithin and USP = unsaponifiable. It has been suggested that behavioural changes may serve as a sensitive indicator of subtle functional dis- orders provoked by toxic agents, particularly in the developing organism (Barlow & Sullivan, 1975; Spyker, 1975). Studies on the importance of dietary lipids for prenatal growth and postnatal behaviour are relatively few but they indicate that lipids play an important role in brain and behavioural development. A number of findings have indicated that the adminis- tration of a lipid-free diet or of a diet deficient in essential fatty acids during pregnancy modifies the lipid biochemistry of the brain and affects postnatal motor reflexes, electrocorticographic activity and learning ability in the offspring (Galli, Messeri, Oli- verio & Paoletti, 1975). In part~ular, a prenatal defi- ciency of essential fatty acids delays neural and be- havioural maturation. It has also been shown that when synthetic diets containing a lipid fraction very rich in phospholipids and odd-chain fatty acids are administered during pregnancy and lactation, behav- ioural development is accelerated and brain bio- chemistry and morphology are modified in the off- spring (Gozzo et al. 1978; Gozzo, Salvati & Di Felice, 1981). The latter data, obtained using the lipid frac- tion of yeasts grown on n-alkanes, are interesting both from a nutritional and from a neurobiological point of view, since they indicate that it is possible by diet- 153