Search Results (7)

Antioxidant capacity and intestinal microbiota play a crucial role in the nutrition, immunity, and overall health status of fish. It is significant to understand the impact of environmental changes on the health of Siniperca scherzeri, an important breeding species. Therefore, in order to investigate the effects of photoperiod (8L: 16D, 12L: 12D and 16L: 8D) and water temperature (18 and 28 °C) on the antioxidant capacity and intestinal microorganisms of S. scherzeri, liver and intestinal samples from cultured juvenile S. scherzeri were collected for related analyses. The photoperiod group of 12L: 12D and the water temperature group of 18 °C presented a higher abundance of Malondialdehyde (MDA) and lower abundances of Superoxide dismutase (SOD), Glutathione peroxidase (GSH-Px), and Catalase (CAT) than other groups (p < 0.05). No significant difference in intestinal microbial diversity was found among different groups (p > 0.05), except that the ACE index showed significant differences among different temperature groups (p < 0.05). Significant differences in the relative abundances of Proteobacteria and Tenericutes were found among different groups (p < 0.05). Modifying the duration of light exposure could effectively mitigate oxidative reactions and optimal high temperatures could suppress oxidation in juvenile S. scherzeri. However, these conditions also influenced the feeding behavior of juvenile S. scherzeri and the composition of intestinal microbiota and promoted the proliferation of opportunistic bacteria. The study provides the valuable data of the aquatic habitat of S. scherzeri. Full article

Mandarin fish (Siniperca chuatsi), golden mandarin fish (Siniperca scherzeri), and Coreoperca whiteheadi are three important aquaculture species in China facing several threats to their production. Genetic diversity was assessed by sequencing the mitochondrial D-loop and cox1 regions in 207 individuals across nine populations. The genetic diversity analysis, based on the concatenated sequences, revealed that the total haplotype diversity was high across all sinipercine fish populations. Population differentiation analysis revealed that most genetic variation was within populations: 74.5% in S. chuatsi (p < 0.001) and 83.0% in S. scherzeri (p < 0.001). All five S. chuatsi populations showed moderate and significant genetic differentiation, and moderate genetic differentiation was observed between the Beijiang and Wujiang populations in S. scherzeri. Phylogenetic and nested clade analysis indicated that artificially bred and wild S. chuatsi populations shared haplotypes, and close phylogenetic relationships were observed between the Beijiang and Dongjiang populations in S. scherzeri. These findings could be useful for the conservation management, artificial breeding, and hybridization of these three sinipercine fish species. Full article

To assess the possibility of using a formulated diet instead of an iced trash fish diet for feeding spotted mandarin fish (Siniperca scherzeri), a 20-week feeding trial was conducted. The objective of the study was to examine the effects of the formulated diet (FG) and the iced trash fish diet (XG) on the growth performance and muscle nutrient composition of the fish. The results showed that the spotted mandarin fish fed with an XG had slightly higher survival rates, weight gain rate, fullness, hepatic index, and viscera index compared to those fed with an FG, although the differences were not significant (p > 0.05). Additionally, in terms of muscle composition, the FG group had higher levels of crude protein and ash content in the fish muscle compared to the XG group (p < 0.05). On the other hand, the crude fat content showed the opposite trend. Among the seventeen amino acids analyzed, only lysine and proline levels differed significantly between the FG and XG groups (p < 0.05). In terms of muscle-hydrolyzed fatty acids, fifteen fatty acids were detected in both groups, with arachidonic acid being exclusive to the FG group. Furthermore, significant differences in the levels of thirteen fatty acids were observed between the two groups (p < 0.05). The FG group had lower levels of saturated fatty acids compared to the XG group (p < 0.05), while monounsaturated fatty acids, polyunsaturated fatty acids, and EPA + DHA contents were higher. This study demonstrates the potential of using a formulated diet as a substitute for an iced trash fish diet in the rearing of spotted mandarin fish. However, further optimization of the formulated diet is necessary to improve the growth of spotted mandarin fish in future research. Full article

To verify the effect of fasting on juvenile leopard mandarin fish (Siniperca scherzeri mean weight, 14.7 g), compensatory growth, body composition, and blood content of juveniles were investigated for six weeks following two-week feeding treatments: fed continuously (control), and fasted for 5 (F5), 10 (F10) and 14 days (F14). Full compensatory growth was evident after four weeks of food resupply in all fasting groups. Specific growth rate, feeding rate, and feed efficiency in all fasting groups were significantly higher than those of the control after the first 2 weeks of food resupply. At the end of fasting, the lipid content, ratio of lipid to lean body mass, hepatosomatic and viscerosomatic indices in all fasting groups, or total cholesterol content in F14 significantly decreased compared to the control. These results indicated that juvenile leopard mandarin fish subjected to 5–14 days of food deprivation could achieve full compensatory growth after feeding resumption for 4 weeks and that the morphological and biochemical indices, as well as body and blood composition, remained comparable to the control group after the completion of the study under our experimental conditions. Full article

The effects of feeding rate (0.5%, 1.0%, 1.5%, 2.0%, 2.5%, and 3.0% body weight [BW] per day [BW day⁻¹]) on the growth, body composition, and blood properties of juvenile mandarin fish, Siniperca scherzeri, (initial BW 18.4 ± 0.2 g) were investigated in a water recirculating aquaculture system. Triplicate groups of fish were fed an experimental diet (55.4% protein, 14.1% lipid) for 10 weeks. Weight gain and specific growth rate increased with increasing feeding rates of up to 2.5% BW day⁻¹, after which no significant increase in growth was observed. Feed efficiency, protein efficiency ratio, and protein retention were not significantly different among the fish fed 1–2.5% BW day⁻¹ but decreased significantly in those fed 3.0% BW day⁻¹. The lipid content of fish fed 2.5% BW day⁻¹ was significantly higher than that at 0.5–1.5% BW day⁻¹. The total plasma cholesterol content was significantly lower in fish fed 0.5 BW day⁻¹ than fish provided with other feeding rates. Based on the growth, feed efficiency, body composition, and blood content analyses, including regression analysis, the optimal feeding rate for juvenile S. scherzeri weighing between 18 g and 54 g was estimated at 1.88–2.80% BW day⁻¹ depending on weight gain, specific growth rate, and feed efficiency under 26.9 °C conditions. Full article

With the development of next generation sequencing technologies, transcriptome level sequence collections are emerging as prominent resources for the discovery of gene-based molecular markers. In this study, we described the isolation and characterization of 46 novel polymorphic microsatellite loci for Siniperca chuatsi and Siniperca scherzeri from the transcriptome of their F₁ interspecies hybrids. Forty-three of these loci were polymorphic in S. chuatsi, and 20 were polymorphic in S. scherzeri. In S. chuatsi, the number of alleles per locus ranged from 2 to 8, and the observed and expected heterozygosities varied from 0.13 to 1.00 and from 0.33 to 0.85, respectively. In S. scherzeri, the number of alleles per locus ranged from 3 to 9, and the observed and expected heterozygosities varied from 0.19 to 1.00 and from 0.28 to 0.88, respectively. We also evaluated the cross-amplification of 46 polymorphic loci in four species of sinipercine fishes: Siniperca kneri, Siniperca undulata, Siniperca obscura, and Coreoperca whiteheadi. The interspecies cross-amplification rate was very high, totaling 94% of the 184 locus/taxon combinations tested. These markers will be a valuable resource for population genetic studies in sinipercine fishes. Full article

In this study, 23 genomic microsatellite DNA markers and 17 express sequence tag (EST)-derived microsatellites were developed and characterized using the fast isolation by AFLP of sequences containing repeats (FIASCO) method and data mining from public EST databases of mandarin fish (Siniperca chuatsi). These polymorphic microsatellite markers were then tested for polymorphism in a wild S. chuatsi population. The number of alleles at 23 genomic SSRs varied from 2 to 19 with an average of 8.0 alleles per locus. The average observed and expected heterozygosities were 0.746 and 0.711, respectively. Of 5361 EST sequences examined, 3.9% (209) contain microsatellites, and di-nucleotide repeats are the most abundant (67.0%), followed by tri-nucleotide (29.7%) and tetra-nucleotide repeats (3.3%). The number of alleles at 17 EST-SSRs varied from 2 to 17 with an average of 8.4 alleles per locus. The average observed and expected heterozygosities were 0.789 and 0.685, respectively. No significant difference of loci polymorphism was found between genomic SSRs and EST-SSRs in terms of number of alleles and heterozygosities. Results of cross-species utility indicated that 13 (52.2%) of the genomic-SSRs and 13 (76.5%) of the EST-SSRs were successfully cross-amplified in a related species, the golden mandarin fish (Siniperca scherzeri). Full article