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Growth selection in fish is essential for aquaculture; however, long generation times and artificial breeding limitations present challenges for breeding endeavors. The tomato grouper (Cephalopholis sonnerati) is an emerging aquaculture species with a generation cycle of at least 5 to 10 years. Mixed culture of broodstocks and natural mating are commonly employed in hatcheries. To expedite the selection process for tomato grouper, we utilized ISSRseq technology for assisted future growth selection. After 6 months of rearing, we selected 48 individuals, including 24 fast‐growing and 24 slow‐growing individuals (representing the top and bottom 10% of samples). These samples produced 932 SNPs. Although specific broodstock pairing information is unavailable, our results suggest that these fry likely originated from multiple broodstock exhibiting considerable diversity. Further analysis of genetic relationships among individuals revealed three main clades. One clade contained a higher proportion of faster‐growing individuals (80%), while another featured a lower proportion of rapidly growing individuals (28.6%). Through the relatedness network and further exclusion of individuals, the faster‐growth clade comprised 92.3% of fast‐growing individuals. The faster‐growth clade is appropriate for further development into a high‐growth strain. Our findings demonstrate that molecular markers can advance population selective breeding to family selection in aquaculture breeding research. [ABSTRACT FROM AUTHOR]

Maintaining proper green water is important for a fish farming pond. However, it remains unclear how to translate this important rule into specific water quality characteristics to associate or even forecast changes in water color. To address this issue, we conducted a study based on daily monitoring of six grouper ponds in Fangliao Township, Pingtung, Taiwan, from March to December 2018. We investigated the relationships between changes in water color and anomalies in water temperature, salinity, and pH, as these three parameters had the most complete records. We employed a long‐short‐term memory model to detect water quality anomalies by computing residual values. Our findings indicate that changes in water color were associated with anomalies in these parameters, with water temperature anomalies being the best indicator for early detection. In fact, the top 5% of water temperature anomalies could predict over 40% of the water color changes. Additionally, pH anomalies occurred immediately after the color changes. This rule‐to‐physicochemical‐parameter paradigm that we developed for grouper ponds could be applied to other aquaculture farms. We anticipate that with the help of advanced environmental surveillance models, such as the one we used, the prospect of autonomous fish farming will be realized. [ABSTRACT FROM AUTHOR]

There are numerous means to improve the tilapia aquaculture industry, and one is to develop disease resistance through selective breeding using molecular markers. In this study, 11 disease-resistance-associated microsatellite markers including 3 markers linked to hamp2, 4 linked to hamp1, 1 linked to pgrn2, 2 linked to pgrn1, and 1 linked to piscidin 4 (TP4) genes were established for tilapia strains farmed in Taiwan after challenge with Streptococcus inae. The correlation analysis of genotypes and survival revealed a total of 55 genotypes related to survival by the chi-square and Z-test. Although fewer markers were found in B and N2 strains compared with A strain, they performed well in terms of disease resistance. It suggested that this may be due to the low potency of some genotypes and the combinatorial arrangement between them. Therefore, a predictive model was built by the genotypes of the parental generation and the mortality rate of different combinations was calculated. The results show the same trend of predicted mortality in the offspring of three new disease-resistant strains as in the challenge experiment. The present findings is a nonkilling method without requiring the selection by challenge with bacteria or viruses and might increase the possibility of utilization of selective breeding using SSR markers in farms. [ABSTRACT FROM AUTHOR]