An orthogonal experimental design OA9 （33） was used to evaluate the effects of vitamins （A, B2, and B6） on the growth and digestive ability of the juvenile Chinese soft-shelled turtle, Pelodiscus sinensis （initial weight, 5.9-0.2 g）. A total of 135 turtles were divided into 9 groups, which each included 15 individuals. The results revealed that vitamin A （VA） had the strongest impacts on the growth rate and feed utilization among the three vitamins; 35,000 IU kg^-1 VA had optimal effects on the feeding intake and specific growth rate, and 20,000 IU kg^-1 VA had optimal effects on protein digestibility and the feed conversion ratio. Vitamin B2 （VB2） was essential for regulating protein deposition and the energy efficiency for growth of the turtles; 120 mg kg^-1 VB2 resulted in increased protein and energy deposition, and 180 mg kg^-1 VB2 had greater beneficial effects on the growth rate. Vitamin B6 （VB6） had important effects on protein and feed efficiency; however, VB6 at an excessive level （120 mg kg^-1） restricted turtle growth. Based on the above growth results, dietary supplementation ofVA, VB2 and VB6 at levels of 35,000 IU kg^-1, 180 mg kg^-1 and 70 mg kg^-1, respectively, were recommended for the juvenile soft-shelled turtle.
Junwei LIZhencai YANGXiaoling HANQuansen XIEHaiyan LIU
