Unsaturated to Saturated Fatty Acids Ratio Adjustmentin Diets on Digestibility and Performance of Growing Pigs

Abstract

SUMMARYFat and oils are the most concentrated energy source for pigs. Various fat sources differ considerably in their physical-chemical characteristics and fatty acid profile. Therefore, the current study aimed to evaluate the effect of diets containing 3% fat with different ratios of unsaturated to saturated fatty acids (U:S) on the nutrient digestibility, energy utilization and growth performance of growing pigs. In experiment 1, a total of 6 crossbred, castrated male pigs (Duroc × Large White × Landrace) were used to determine the nutrient digestibility and energy utilization according to a repeated 3 × 3 Latin square design. Each of the two pigs was fed with one of the three diets containing 3% fat with a U:S ratio of 3, 4 or 5, respectively. No differences (P>0.05) in the nutrient digestibility were observed among groups, but the highest digestible and metabolizable energy (P<0.05) appeared in pigs receiving the dietary U:S ratio of 4. In experiment 2, a total of 30 pigs (with an equal number of entire males and females) were allotted into 3 groups in a randomized complete block design. Pigs were fed a diet without fat (T1), or the diets containing 3% fat with U:S ratio of 4 (T2) or 5 (T3), respectively.Although there were no significant difference in any growth criteria, average daily gain and feed conversion ratio was slightly improved (P>0.05) in the T2 group. In conclusion, the present results suggest that diets containing 3% fat with a U:S ratio of 4 is optimal for improving energy utilization in growing pigs and results in a slight enhancement of performance.