Two trials were conducted to evaluate the effect of diets with different levels of anti‑nutritional factors: trypsin (TIU) and chymotrypsin (CIU) inhibitors units of peas and γGlutamyl‑S‑Ethenyl‑Cysteine (GEC) of narbon vetch, in productive performance of pigs from 40 to 61 days of age. 192 barrows were used in each test, Duroc hybrid x (Large White x Landrace), with 11.23 and 11.55 kg body weight respectively, and the same experimental design: four treatments and eight replicates with six piglets in each case. In trial 1 treatments were: Control: soybean meal 47 and soybean extruded (0.97 TIU‑1.94 CIU/mg feed); P-CAR: soybean extruded and pea Cartouche (1.62 TIU‑3.16 CIU/mg feed); P‑ICE: soybean extruded and pea Iceberg (3.09 TIU‑4.95 CIU/mg feed); P‑LUN: soybean extruded and pea Luna (3.19 TIU‑5.56 CIU/mg feed). The piglets of P‑CAR treatment grew significantly faster than the others, with the same intake and feed conversion. No significant differences between Control, P‑ICE and P‑LUN. In trial 2 the feedstuff had different levels of narbon vetch: 0%, 5%, 15% and 25%, and consequently of γGlutamyl‑S‑Ethenyl‑Cysteine (1.52% of the grain). The piglets that consumed the treatment of 5% had higher intake and growth, and the same conversion that piglets feeding with the treatment of 0%. The performance worsened significantly with increasing 15%. We conclude that piglets in starter period maintain or improve the performance with intake of proteases inhibitors in feedstuff that exceed 3.28 (TIU) and 2.86 (CIU) times those of a control diet, and that the inclusion of 5% of narbon vetch in feedstuff increases feed intake and growth.