Standardized ileal digestibility of valine in granulated valine biomass is not different from that in crystalline L-valine in growing pigs

Abstract

The objective of the present study was to determine the coefficient of standardized ileal digestibility (CSID) of crude protein (CP) and Val in Val biomass (VB; 737 g/kg Val) fed to pigs with the hypothesis that the CSID of Val in VB is comparable to that in crystalline L-Val. Eight barrows (initial body weight = 58.4 ± 3.3 kg) fitted with a T-cannula at the distal ileum were fed 4 diets for 4 periods in a replicated 4 × 4 Latin square design to obtain 8 replications for each experimental diet. A basal diet consisted of 759 g/kg corn and 110 g/kg soybean meal as the sole source of amino acids (AA). Two experimental diets were prepared by adding L-Val at 75 g/kg and VB at 100 g/kg to the basal diet at the expense of corn and soybean meal. Additionally, a nitrogen-free diet was also prepared to determine the basal endogenous losses of CP and AA. Chromic oxide was included at 5 g/kg as an indigestible index in all diets. Each period consisted of a 4-day adaptation period and a 2-day ileal digesta collection period. The coefficient of apparent ileal digestibility (CAID) and CSID of CP and Val in the L-Val and VB were calculated using the difference procedure. The CAID of Lys in the crystalline L-Val diet was less than that in the VB diet (P < 0.05). The values for CSID of most AA except for Lys (P = 0.049) and Val (P < 0.001) did not differ among the three experimental diets. Based on the difference procedure, the values for CSID of Val were not different between crystalline L-Val and VB (0.996 and 0.998, respectively). In conclusion, the Val biomass used in the present work contains 737 g/kg of Val and the Val in the Val biomass is highly digestible, which is comparable to crystalline L-Val.