Taurine is usually included in fish feed as a nutritional supplement, and it can also improve feed performance. To assess the potential use of taurine as a feed attractant in plant protein-based diets, we examined four different concentrations of taurine to determine the optimal levels for attracting large yellow croaker (Larimichthys crocea). The fish displayed the most significant attractive responses to 3.5% taurine and showed good feed performance with an all-plant protein diet supplying 3.5% taurine. Next, deep sequencing of the olfactory epithelium was conducted to identify genes differentially expressed in the taurine group (Tau) versus controls.We found that 11,793 unigenes were differentially expressed: 10,795 were upregulated and 998 were down-regulated unigenes. We detected 77 olfactory receptor genes, including 37 up-regulated unigenes, and validated the expression dynamics of eight genes using quantitative reverse transcription-PCR (RT-qPCR). We utilized Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) to analyse the function of the differentially expressed genes, which were mainly involved in signaling and cell communication (GO) and olfactory transduction (KEGG). Cumulatively, our results indicate that taurine could be a good phagostimulant for plant protein-based diets for L. crocea. Furthermore, improved understanding via olfactory epithelium transcriptomic analysis would inform the development of an all-plant protein diet for L. crocea. K E Y W O R D S all-plant protein diets, Larimichthys crocea, olfactory-related genes, taurine, transcriptomic analysis for Zhejiang Marine High-Efficiency and

The harmonic constants extracted from tidal gauge stations and satellite altimeter observations are usually sparsely distributed in the continental marginal seas, but they are precious data for addressing the main characteristics of different constituents. In this paper, a dynamically constrained interpolation methodology (DCIM) is developed and applied to interpolate the observed harmonic constants of the M2 constituent from satellite altimeter observations in the Bohai, Yellow, and East China Seas (BYECS) with those from tidal gauge stations for validation. In the DCIM, the tide model provides dynamical constraints to interpolate the observations, and the adjoint assimilation method provides iterative optimization for the interpolated results by adjusting key model parameters. In particular, a substantial quantity of enhanced “observations” generated from the interpolated results of the domain are further interpolated with the sparse observations in the subdomain. The final interpolated results for each subdomain, naturally blending the dynamical constraints from the dynamical model with statistical information from observations, can describe the main characteristics of the M2 constituent in the BYECS, the continental shelf sea of the East China Sea, and the Zhejiang–Fujian coastal area, respectively. The results indicate that the DCIM is feasible and effective to utilize the observations to obtain high-accuracy cotidal charts for regional ocean.

The long-term trend and interannual variation of ocean heat content (OHC) in the Bohai Sea, Yellow Sea, and East China Sea (BYECS) were examined using 27 years (1993–2019) of daily reanalysis data from the Japan Coastal Ocean Predictability Experiment 2 (JCOPE2M). The annual mean OHC was 4.25 × 1021 J, with a linear warming rate of 0.13 W m−2 with a confidence level of 95%. The spatial distributions for the annual and linear trends of OHC in the BYECS were inhomogeneous, and a considerable quantity of heat was stored on the outer shelf. The warming rate was considerably elevated in the areas northeast of Taiwan and southwest of Kyushu, showing a rate greater than that of the Pacific and global oceans by a factor of 4–5. Heat budget analysis indicated that the Taiwan Strait (TAS) is the dominant source of heat for the BYECS. The mechanisms of the OHC interannual variation in the outer and inner shelves varied. On the outer shelf, the OHC interannual variation was dependent on the Kuroshio onshore intrusion, while on the inner shelf, the OHC interannual variation was related to the variation in air-sea heat flux. The rapid warming in the outer shelf corresponded to the increasing trends of heat transport across northeast Taiwan and southwest Kyushu, which were dominated by the temporal variation of current velocity.