Introduction
Vitamins A and D are essential micronutrients involved in growth, epithelial integrity, immune regulation and metabolic homeostasis in aquatic animals. Vitamin D3 exerts its biological effects through the vitamin D receptor (VDR), which forms a heterodimer with retinoid X receptor (RXR), suggesting that dietary vitamin A status may modulate physiological responses to vitamin D3. Previous studies have shown that dietary vitamin D3 can affect growth performance and physiological responses in P. vannamei (Dai et al., 2022; Lee and Lee, 2025). However, information on the combined effects of dietary vitamin A and vitamin D3 in this species remains limited. Therefore, this study was designed to evaluate the interactive effects of dietary vitamin A and vitamin D3 in juvenile P. vannamei.
Materials and Methods
A 2 × 4 factorial design was established with two dietary vitamin A levels (0 and 1.8 mg kg-1) and four dietary vitamin D3 levels (0, 30, 60 and 120 μg kg-1), resulting in eight experimental diets designated as A0D0, A0D30, A0D60, A0D120, A1.8D0, A1.8D30, A1.8D60 and A1.8D120, respectively. Juvenile P. vannamei (initial body weight, 0.78 ± 0.01 g) were randomly distributed into 32 tanks (20 shrimp per tank), with four replicate tanks per treatment. An 8-week feeding trial is currently in progress. HPLC analysis determined dietary vitamin D3 concentrations of 1.6, 37.0, 65.1, 121.6, 2.0, 39.7, 64.7 and 121.7 μg kg-1, and dietary vitamin A concentrations of 0.23, 0.23, 0.23, 0.24, 2.00, 1.99, 2.01 and 2.00 mg kg-1corresponding to diets 1 to 8, respectively. Growth performance and survival are being monitored biweekly. At the end of the feeding trial, feed utilization, biochemical and physiological responses, digestive enzyme activity, innate immune responses, antioxidant capacity, histological parameters and gene expression related to vitamin A and vitamin D signaling, antioxidant defense, immunity and lipid metabolism will be evaluated.
Results
At both weeks 2 and 4, survival remained 100% across all treatments. At week 2, no significant effects of dietary vitamin A, vitamin D3, or their interaction were observed for weight gain and specific growth rate (P > 0.05). At week 4, weight gain was significantly affected by dietary vitamin A (P < 0.001), vitamin D3 (P = 0.001) and their interaction (P = 0.018). Similarly, specific growth rate was significantly affected by dietary vitamin A (P < 0.001), vitamin D3 (P = 0.001) and their interaction (P = 0.022). Final results from the 8-week feeding trial will be further presented and discussed.
Conclusion
Dietary vitamin A, vitamin D3 and their interaction significantly affected growth performance in juvenile P. vannamei at week 4. Completion of the feeding trial, along with subsequent physiological and molecular analyses, is expected to provide further insights into the nutritional roles and potential interactions of these two vitamins in P. vannamei.
Reference
Dai, T., Jiao, L., Tao, X., Lu, J., Jin, M., Sun, P., & Zhou, Q. (2022). Effects of dietary vitamin D3 supplementation on the growth performance, tissue Ca and P concentrations, antioxidant capacity, immune response and lipid metabolism in Litopenaeus vannamei larvae. British Journal of Nutrition, 128(5), 793-801. https://doi.org/10.1017/S0007114521004931
Lee, Y., & Lee, K. J. (2025). Vitamin D3 Improves Growth Performance, Digestive Enzyme Activity, Antioxidant Capacity, Lipid Metabolism, Histomorphology, Ca and P Homeostasis and Ammonia Stress Resistance in Pacific White Shrimp (Penaeus vannamei). Marine Biotechnology, 27(4), 118. https://doi.org/10.1007/s10126-025-10497-y