Effects of different light spectra on embryo development and the performance of newly hatched turbot (Scophthalmus maximus) larvae

• Published in: Fish & Shellfish Immunology
• Main Authors: Wu, Lele, Han, Mingming, Song, Zongcheng, Xu, Shihong, Li, Jun, Li, Xueqing, Wang, Yanfeng, Yue, Xinlu, Li, Xian
• Format: Report
• Language: English
• Published: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD 2019
• Subjects: Scophthalmus maximus; Light spectrum; Embryo; Newly hatched larvae; Fisheries; Immunology; Marine & Freshwater Biology; Veterinary Sciences; Turbot
• Online Access: http://ir.qdio.ac.cn/handle/337002/161780; http://ir.qdio.ac.cn/handle/337002/161781; https://doi.org/10.1016/j.fsi.2019.05.007

Light is a key environmental factor that synchronizes various life stages from embryo development to sexual maturation in fish. For turbot, light spectra have the most influence at the larval and juvenile stages. In the current study, differences in the development of embryos and the performance of newly hatched turbot larvae exposed to five different spectra: full spectrum (LDF), blue (LOB, peak at 450 nm), green (LDG, peak at 533 nm), orange (LDO, peak at 595 nm) and red (LDR, peak at 629 nm), were examined. At 62.8 h post fertilization, a higher number of embryos exposed to short-wavelengths (LDG and LOB) had developed a heartbeat in comparison with embryos exposed to other wavelengths. Larvae exposed to the green spectrum had higher malformation rates than larvae exposed to the other spectra, indicating that larvae exposed to green light may have significantly reduced survival rates. The results of non-specific immunity parameters showed that the mRNA expression levels of cathepsin D (CTSD), cathepsin F (CTSF), catalase (CAT) and metallothionein (MT) in larvae exposed to LDB were significantly higher than those exposed to other spectra, but CAT activity in larvae exposed to LDB was significantly lower than larvae exposed to the other spectra. There was no significant difference in MT activity in larvae exposed to the five different spectra. The mRNA expression level of lysozyme (LZM) in larvae exposed to LDR was significantly higher than other spectra, while there was no significant difference in LZM activity observed in larvae exposed to LDR, LDG, LDB and LDF. The difference of the enzyme activity of total superoxide dismutase (T-SOD) was not significant among larvae exposed to the five spectra. mRNA expression of the heat shock protein 70 (HSP70) was significantly higher in newly hatched larvae exposed to LDB, LDR and LDG, indicating that larvae exposed to LDB, LDG and LDR exhibited a stress response. The mRNA expression level of the insulin-like growth factor-1 (IGF-1) and growth parameters in the newly ...