EFFECT OF FATTY-ACID PROFILE ON DIGESTIBI LITY OF DIETARY FATS IN THEINTESTINE OF PIGS

An experiment with 10 castrated male pigs was performed to study the i nfluence on growth characteristics and digestibility of energy (dE) of diets without fat supplementation (K) or supplemented with either ext racted fat (EF), pig fat (SF), or two different powder fats (PF1 and P F2) at 10 %. Digestibility of crude fat and fatty acids were determine d in three parts of the intestine (ileum, caecum, rectum) at slaughter . The supplemented dietary fats differed in energy content and fatty a cid profile. The energy value of EF and SF (39.4 and 39.6 MJ/kg) was h igher than that of PF1 and PF2 (37.5 and 35.7 MJ/kg). The relative con tent of saturated (47, 38, 64, 74 %), monoenic (45, 50, 36, 26 %) and polyenic fatty acids (8, 12, 0.4, 0.8 %) varied between the four dieta ry fats. Fat supplementation improved average daily weight gain and fe ed-conversion ratio by up to 16 %. However, no differences were detect ed between diets supplemented with different fats. The dE was signific antly higher in diet SF (0.884) than in the other diets (0.853). The c alculated dE of fat SF (0.883) was higher than that of fat EF (0.767), PF1 (0.770) and PF2 (0.749). Chyme analysis showed that crude fat and fatty acids are largely absorbed before the terminal ileum. SF fat ha d the highest digestibility (0.789) and EF (0.627) had the lowest. Ind ependently of utilized fat, the absorption of oleic and linoleic acid was better than that of stearic acid. Absorption of unsaturated fatty acids was virtually complete. The digestibility of palmitic and steari c acid of PF1 (0.806 and 0.513) and PF2 (0.746 and 0.647) were better than that of EF (0.610 and 0.511) and SF (0.669 and 0.471).