Study On Requirements Of Standardized Ileal Digestible Valine For Growing-Finishing Pigs

Three experiments were conducted to investigate the requirements of standardized ileal digestible valine (SID Val) for growing-finishing pig fed diets supplemented with crystalline amino acids (CAA).(1) Experiment1contained420barrows (Duroc×Landrace×Yorkshire) which were allotted to five treatments with six pens per treatment to determine the effects of different levels of dietary valine on growth performance and plasma urea nitrogen (PUN) of grower pigs. Average initial body weight was24.31=2.52kg. In experiment1. the treatments consisted of the corn soybean diet meeting the Nutrient Requirements of Swine (NRC,2012), therefore dietary SID Lysine (Lys)0.98%was used in the subsequent experiment, but five different valine levels (0.59%;0.64%;0.69%;0.74%and0.79%) supplemented with CAA diets. The growth performances were significantly affected by the dietary SID valine requirement. Broken-line and quadratic regression analysis of the data from growth performance showed that the SID Val requirement was between0.65to0.73%(0.66to0.74SID Val:Lys), the optimum SID Val was0.68%(0.69SID Val:Lys) for20to50kg growing pigs.(2) Experiment2contained360barrows (Duroc×Landrace×Yorkshire) which were allotted to five treatments with six pens per treatment to determine the effects of different levels of dietary valine on growth performance and PUN of finishing pigs (50～80kg). Average initial body weight was53.75±2.63kg. In experiment2, the treatments consisted of the corn soybean diet meeting the Nutrient Requirements of Swine (NRC,2012); therefore dietary SID Lys0.85%was used in the subsequent experiment, but five different valine levels (0.50%;0.55%;0.60%;0.65%and0.70%) supplemented with CAA diets. The growth performances were significantly affected by the dietary SID Val requirement. Broken-line and quadratic regression analysis of the data from growth performance showed that the SID valine requirement was between0.61to0.66%(0.72to0.78SID Val:Lys), the optimum SID valine is0.65%(0.76SID Val:Lys) for50to80kg finishing pigs.(3) Experiment3contained360barrows (Duroc×Landrace×Yorkshire) which were allotted to five treatments with six pens per treatment to determine the effects of different levels of dietary valine on growth performance and PUN of finishing pigs (80～120kg). Average initial body weight was83.67±2.92kg. In experiment3, the treatments consisted of the corn soybean diet meeting the Nutrient Requirements of Swine (NRC,2012), therefore dietary SID Lys0.74%was used in the subsequent experiment, but five different valine levels (0.43%;0.48%;0.53%;0.58%and0.63%) supplemented with CAA diets. The growth performances were significantly affected by the dietary SID valine requirement. Broken-line and quadratic regression analysis of the data from growth performance showed that the SID valine requirement was between0.52to0.56%(0.70to0.76SID Val:Lys), the optimum SID valine was0.53%(0.72SID Val:Lys) for80to120kg pigs. In conclusion, the requirements of SID Val were0.68%,0.65%and0.53%for growing-finishing pig, respectively.