In order to fine-tune the standardized ileal digestible (SID) lysine (Lys) requirement of modern piglets (RA-SE genetics hybrid sow X Piétrain boar), two dose-response studies to Lys were conducted in 4 to 9 week-old piglets. In Experiment 1, only commercially available feed-grade amino acids (AA) were used, without maintaining dietary crude protein (CP; 20 to 21 %). In Experiment 2, all the range of needed AA was used while dietary CP was kept constant at 18 % by adding L-Glu. In both experiments, SID Lys ranged from 0.85 to 1.35 %, divided over five steps. Six (Experiment 1) or nine (Experiment 2) pens of six piglets were used per Lys level. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) showed a response to increased dietary Lys level in both trials. In Experiment 1, it was not possible to reach an optimum for any of the growth parameters using a non-linear regression model, suggesting an optimum above 1.35 % SID Lys. In contrast, in Experiment 2, maximum response was observed at 1.14 and 1.29 % SID Lys, for ADG and FCR, respectively, using a curvilinear-plateau model. While maximal performance was similar in both experiments (ADG = 450 g/d, FCR = 1.3), the effect of Lys shortage was higher in Experiment 1, probably due to an imbalanced AA:Lys ratio. On the other hand, in Experiment 2, at the highest dietary Lys level, the SID Lys:CP ratio was 7.5 %, suggesting that nitrogen or non-essential AA may have become limiting.
|Titel||49èmes Journées de la Recherche Porcine|
|Status||Gepubliceerd - 2017|
|Evenement||49emes Journées de la Recherche Porcine - Paris, Frankrijk|
Duur: 31-jan-2017 → 1-feb-2017