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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]

Abstract Amplified fragment length polymorphism (AFLP) with multicolored fluorescent molecular markers was used to analyze duck (Anas platyrhynchos) genomic DNA and to construct the first AFLP genetic linkage map. These markers were developed and genotyped in 766 F2 individuals from six families from a cross between two different selected duck lines, brown Tsaiya and Pekin. Two hundred and ninety-six polymorphic bands (64% of all bands) were detected using 18 pairs of fluorescent TaqI/EcoRI primer combinations. Each primer set produced a range of 7 to 29 fragments in the reactions, and generated on average 16.4 polymorphic bands. The AFLP linkage map included 260 co-dominant markers distributed in 32 linkage groups. Twenty-one co-dominant markers were not linked with any other marker. Each linkage group contained three to 63 molecular markers and their size ranged between 19.0 cM and 171.9 cM. This AFLP linkage map provides important information for establishing a duck chromosome map, for mapping quantitative trait loci (QTL mapping) and for breeding applications.

Abstract: The sub- interdigitated microelectrodes presented in this work aims at achieving a high collection efficiency for electrochemical dopamine (DA) detection. Through nanoimprint technology, sub- microelectrodes can be batch fabricated without relying on the expensive electron-beam lithography repeatedly. The applied reduction and oxidation potentials are determined by cyclic voltammetry at −0.2 V and 0.6 V. The effectiveness of nanoimprinted electrodes is clearly illustrated by the small deviations of produced electrochemical currents with respect to analytic values. The sensitivities are 2.89 and 1.73 nA/μM for interdigitated microelectrodes with gaps of 300 and 600 nm. The average collection efficacy values are 97.9% and 95.4%, respectively. Signal transduction is achieved by a CMOS sensing circuit. The detectable resolution is about 0.1 μM. [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]

Myogenic progenitor cell (MPC) is responsible for postembryonic muscle growth and regeneration. Progranulin (PGRN) is a pluripotent growth factor that is correlated with neuromuscular disease, which is characterised by denervation, leading to muscle atrophy with an abnormal quantity and functional ability of MPC. However, the role of PGRN in MPC biology has yet to be elucidated. Here, we show that knockdown of zebrafish progranulin A (GrnA) resulted in a reduced number of MPC and impaired muscle growth. The decreased number of Pax7-positive MPCs could be restored by the ectopic expression of GrnA or MET. We further confirmed the requirement of GrnA in MPC activation during muscle regeneration by knockdown and transgenic line with muscle-specific overexpression of GrnA. In conclusion, we demonstrate a critical role for PGRN in the maintenance of MPC and suggest that muscle atrophy under PGRN loss may begin with MPC during postembryonic myogenesis.

Aim: To investigate the outcomes, as well as risk factors for 6-wk mortality, in patients with early rebleeding after endoscopic variceal band ligation (EVL) for esophageal variceal hemorrhage (EVH)., Methods: Among 817 EVL procedures performed for EVH between January 2007 and December 2008, 128 patients with early rebleeding, defined as rebleeding within 6 wk after EVL, were enrolled for analysis., Result: The rate of early rebleeding after EVL for acute EVH was 15.6% (128/817). The 5-d, 6-wk, 3-mo, and 6-mo mortality rates were 7.8%, 38.3%, 55.5%, and 58.6%, respectively, in these early rebleeding patients. The use of beta-blockers, occurrence of hypovolemic shock, and higher model for end-stage liver disease (MELD) score at the time of rebleeding were independent predictors for 6-wk mortality. A cut-off value of 21.5 for the MELD score was found with an area under ROC curve of 0.862 (P < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value were 77.6%, 81%, 71.7%, and 85.3%, respectively. As for the 6-mo survival rate, patients with a MELD score ≥ 21.5 had a significantly lower survival rate than patients with a MELD score < 21.5 (P < 0.001)., Conclusion: This study demonstrated that the MELD score is an easy and powerful predictor for 6-wk mortality and outcomes of patients with early rebleeding after EVL for EVH.