The effect of feeding lentil on growth performance and diet nutrient digestibility in starter pigs

The effects of substitution of soybean meal with increasing levels of green lentil (Lens culinaris) were evaluated in 240 starter pigs from 9 to 20 kg. Five pelleted wheat-based diets containing 0, 75, 150, 225, or 300 g lentil/kg were formulated to contain 9.76 MJ net energy (NE)/kg and 1.20 g standardised ileal digestible lysine (Lys)/MJ NE and were fed for 3 weeks starting 2 weeks after weaning at 19 days of age. Lentil was added by replacing soybean meal and wheat and the diets were balanced for NE using canola oil and for amino acids using crystalline Lys, threonine, methionine and tryptophan. Increasing dietary inclusion of lentil linearly decreased (P<0.001) the diet apparent total tract digestibility coefficient for crude protein from 0.821 to 0.798 and digestible energy value from 14.4 to 14.0 MJ/kg. For the entire trial (day 0–21), increasing dietary inclusion of lentil linearly decreased (P<0.05) average daily gain (ADG) and quadratically reduced (P<0.01) feed efficiency (G:F). Specifically, pigs fed 75–225 g lentil/kg had a similar ADG and G:F than pigs fed 0 g lentil/kg, whilst the inclusion of 300 g lentil/kg reduced (P<0.01) both ADG and G:F by 10%. Differences in feed intake were not observed (P>0.05). In conclusion, inclusion of green lentil should not exceed 225 g/kg in diets for nursery pigs to maintain similar performance as pigs fed a diet with soybean meal as the main supplemental protein feedstuff.