HEMATOLOGICAL AND LIPID CHANGES IN NEWBORN PIGLETS FED MILK REPLACER DIETS CONTAINING VEGETABLE-OILS WITH DIFFERENT LEVELS OF N-3 FATTY-ACIDS

To test if linolenic acid (18:3n-3) from vegetable oils would affect b leeding times and platelet counts in newborns, piglets were used as a model fed milk replacer diets containing 25% (by wt) vegetable oils or oil mixtures for 28 d and compared to sow reared piglets. The oils te sted included soybean, canola, olive, high oleic sunflower (BOAS), a c anola/coconut mixture and a mixture of oils mimicking canola in fatty acid composition All piglets fed the milk replacer diets showed normal growth. Bleeding times increased after birth from 4-6 min to 7-10 min by week 4 (P < 0.001), and were higher in pigs fed diets containing 1 8:3n-3, as well as in sow-reared piglets receiving n-3 polyunsaturated fatty acids (PUFA) in the milk, as compared to diets low in 18:3n-3. Platelet numbers increased within the first week in newborn piglets fr om 300 to 550 x 10(9)/L, and remained high thereafter. Milk replacer d iets, containing vegetable oils, generally showed a transient delay in the rise of platelet numbers, which was partially associated with an increased platelet volume. The oils showed differences in the length o f delay, but by the third week of age, all platelet counts were >500 x 10(9)/L. The delay in rise in platelet counts appeared to be related to the fatty acid composition of the oil, as the effect was reproduced by a mixture of oils with a certain fatty acid profile, and disappear ed upon the addition of saturated fatty acids to the vegetable oil. Th ere were no alterations in the coagulation factors due to the dietary oils. Blood plasma, platelets and red blood cell membranes showed incr eased levels of 18:3n-3 and long-chain n-3 PUFA in response to dietary 18:3n-3. The level of saturated fatty acids in blood lipids was gener ally lower in canola and BOAS oil fed piglets as compared to piglets f ed soybean oil. or reared with the sow. The results suggest that consu mption of milk replacer diets containing vegetable oils rich in 18:3n- 3 does not represent a bleeding risk, and that the transient lower pla telet count can be counterbalanced by the