Nutritive value of flaxseed meal fed to growing pigs

The study was conducted to determine the coefficient of apparent (CAID) and standardized ileal digestibility (CSID) of crude protein (CP) and amino acids (AA), the digestible energy (DE), metabolisable energy (ME) and calculated net energy (NE) values of flaxseed meal (FM) fed to growing pigs. Nine ileal-cannulated Genesus [(Yorkshire-Landrace♀ × Duroc ♂)] barrows (46.0 ± 1.66 kg BW) were randomly assigned to one of the three experimental diets in a 3 × 3 Latin square design with three pigs per diet per period to give nine replicates per treatment. The experimental diets were; a corn-soybean meal diet (Basal), FM plus corn-soybean meal-based diet (Basal-FM) and low N-casein diet. The basal diet was formulated to meet nutrient requirements for growing pigs. The Basal-FM was formulated by replacing a portion of corn and soybean meal in the basal diet with 278 g/kg of FM. Titanium dioxide (TiO2; 3 g/kg) was added in all diets as an indigestible marker. The CAID and CSID of AA and CP as well as the DE and ME values of FM were calculated by the difference method. The NE value of FM was calculated using the determined ME value and analysed macronutrient content according to Noblet et al. (1994): NE = (0.726 × ME) + (13.3 × % Ether extract) + (3.9 × % starch) − (6.2 × %CP) − (8.3 × % ADF). The GE, CP, Lys, Met, Thr, ether extract, NDF, ADF, water holding capacity, swelling capacity and bulk density of FM were 19.5 MJ/kg, 339, 12.21, 6.01, 12.21, 78, 416, 147 g/kg, 8.31 mL/g, 4.05 mL/g and 0.737 g/mL, respectively. The CAID of CP, Lys, Met and Thr for FM were 0.59, 0.62, 0.65 and 0.58, respectively. The CSID of CP, Arg, His, Ile, Leu, Lys, Thr, Trp, Phe and Val for FM were 0.71, 0.79, 0.66, 0.72, 0.71, 0.63, 0.70, 0.68, 0.72 and 0.68, respectively. The DE, ME and calculated NE values of FM were 12.6, 11.4 and 7.5 MJ/kg, respectively. In conclusion, using the CSID of AA and calculated NE values obtained in the current study, flaxseed meal can be incorporated in growing pig diets as an alternative source of dietary protein and energy.