Influence of Feed Grade Amino Acid Inclusion Level in Late Nursery and Grower Diets Fed to Pigs from 21 to 75 lb

A total of 912 pigs (PIC TR4 × (Fast LW PIC L02); initially 21.4 lb) were used in a 43-d trial to evaluate the influence feed grade amino acid diets containing 30% dried distillers grains with solubles (DDGS) fed from 21 75 lb. Pigs randomly assigned pens (19 per pen) and allotted weight blocks 1 4 dietary treatments 12 treatment. Dietary contained low, medium, high, or very high additions acids L-lysine added at approximately 0.25, 0.40, 0.55, 0.70% diet. This corresponded 15, 24, 33, 42% standardized ileal digestibility (SID) lysine coming L-lysine. All other as needed meet minimum desired ratios relative (60% Ile; 58% Met Cys; 65% Thr; 19% Trp; 72% Val). Predetermined orthogonal contrasts linear quadratic effects based on ratio. Overall (d 0 43), there was an increase (quadratic, P < 0.020) average daily gain (ADG) intake (ADFI), increasing having increased up addition decreasing for For overall efficiency (F/G), medium had improved F/G (P = 0.002) compared levels acids, low intermediate. As diet, blood urea nitrogen decreased (linear, 0.001) d 43. In summary, percentage proportion SID diet 15 (Low) 24% (Medium), ADG improved; however, greater than 24%, worsened.