Oxidation of U‐13C‐α‐linolenic acid is independent of body weight in pigs fed flaxseed diets

Abstract

Twelve pigs (14.6±0.41 kg initial body weight, BW; 4 pigs per treatment) were used to assess the effect of BW and cumulative intake of flaxseed (FS) on the oxidation of α‐linolenic acid (ALA). Pigs were fed FS free (CON) or FS diets according to three feeding regimes: R1, 10% FS diet from 15 to 37 kg BW; and then 5% FS diet; R2, CON from 15 to 37 kg BW; and then 5% FS diet; and R3, 10% FS diet form 15 to 37 kg BW; and then CON. At 25 and 55 kg BW, a single bolus dose of U‐13C‐ALA (2.75 mg/kg BW) was fed and recovery of 13C in expired CO2 was quantified during 26 h to estimate oxidation. There were no interactive effects (P>0.10) of feeding regime and BW on ALA oxidation. There was no effect of previous FS intake on ALA oxidation at 55 kg BW (P=0.20; 8.0% for R1 and 4.9% for R2). Across BW, R1 tended to have higher mean ALA oxidation than R2 (P=0.06; 9.8 vs 5.1%), whereas mean oxidation was similar for R2 and R3 (P=0.94; 5.1 vs 5.7%). BW did not affect the oxidation of ALA (P=0.42; 7.0 at 25 kg and 5.6% at 55 kg BW); pigs on FS tended to have higher ALA oxidation than pigs on CON (P=0.07; 8.0 vs 4.7%). ALA oxidation was generally less than 10% of intake, not affected by BW and previous nutrition, and reduced when feeding low ALA diets.Grant Funding Source : Ontario Pork, OMAFRA, AAFC