Ethanol Consumption by Lactating Rats Induces Changes in Pup's Fatty Acid Profiles

From parturition, lactating Wistar rats were given 20% ethanol in drinking water and solid diet ad libitum (ET group) or were pair-fed to the ET group (PF group) or were given water and solid diet ad libitum (control group, C). Animals were studied on day 12 of lactation and/or treatment, when dams were separated from their litters and 2-4 hours latter they were i.p. injected with oxytocin for milk collection under anaesthesia. Maternal food intake, weight gain and pup's body weight were lower in ET than in C rats. When compared to C rats, milk of ET dams had a decreased proportion of C14:0 and C22:6 n-3 fatty acids while an increase in C18:0,C16:1 and C18:1 n-9 was detected, whereas when compared to PF it had higher C8:0,C10:0,C18:0,C18:1 n-9, C18:2 n-6 and lower C20:5 n-3 and C22:6 n-3. Body weight was lower in pups from ET than in those from C or PF, and whereas brain weight and brain lipid content was lower in ET and PF pupsthan in C, total phospholipid (PL) brain content was similar among the groups. The ratio of C20:3 n-9 to C20:4 n-6 in brain PL was higher in ET pups than in either C or PF, indicating an essential fatty acid deficiency in the formers. Ethanol treatment also decreased the proportional amount of C18:2 n-6, C18:3 n-3, C20:4 n-6, C20:5 n-3 and C22:6 n-3 in brain PL as compared to C, whereas from these fatty acids only C18:3 n-3, C20:5 n-3 and C22:6 n-3 were decreased in PF. On the other hand, the proportion of C22:6 n-3 was significantly lower in the pups of ET group than in PF animals. Present results show that maternal intake of ethanol during lactation in the rat modifies milk lipid composition and that these effects are not caused by the undernutrition condition of the animals. These effects alter fatty acid composition of brain PL in pups, and such effect may contribute to its abnormal development.