Abstract
BackgroundThe mandarin fish (Siniperca chuatsi) is an important and widely cultured fish in China. However, the lack of selective breeding of mandarin fish in previous decades has resulted in a decline in the growth rate of pond-cultured fish, a shortened period of sexual maturity, and reduced disease resistance; these issues seriously affect the quality and safety of the fish products. Therefore, it is necessary to establish a selective breeding program for the mandarin fish to improve the economical traits of the fish and to sustain the development of the mandarin fish industry.ResultsWe constructed a high-density linkage map for it based on double digest restriction site associated DNA sequencing (ddRAD-Sequencing). This map contained 3283 dimorphic single nucleotide polymorphism markers and 24 linkage groups (LGs). The total map-length was 1972.01 cM, with an average interlocus distance of 0.61 cM. One significant quantitative trait locus (QTL) for sex determination trait was detected on LG23, which was supported by five markers, clustered between 60.27 and 68.71 cM. The highest logarithm of odds value (17.73) was located at 60.27 cM, near the marker r1_73194, accounting for 53.3% of the phenotypic variance. Genotypes of all the male fish on r1_33008 were homozygous, whereas those of all females were heterozygous. Thus, LG23 was considered a sex-related linkage group. Eleven significant QTLs, for three growth traits, at two growth stages and the increased values were distributed on four LGs; their contributions to the phenotypic variation were quite low (12.4–17.2%), suggesting that multiple genes affected the growth traits.ConclusionThis high-resolution genetic map provides a valuable resource for fine-mapping of important traits and for identification of sex-related markers that should facilitate breeding of all-female mandarin fish for aquaculture and mechanistic studies on sex determination.
Highlights
The mandarin fish (Siniperca chuatsi) is an important and widely cultured fish in China
As with many other cultured fish species, the lack of selective breeding of mandarin fish in previous decades has resulted in a decline in the growth rate of pond-cultured fish, a shortened period of sexual maturity, and reduced disease resistance; these issues seriously affect the quality and safety of the fish products [4]
One major quantitative trait locus (QTL) (LG23) related to sex determination was supported by five markers that were found to cluster at a narrow linkage span (60.27–68.71 cM) of LG23, contributing to 37.1–53.3% of the phenotypic variation, indicating that this was the sex determination QTL in the mandarin fish
Summary
The mandarin fish (Siniperca chuatsi) is an important and widely cultured fish in China. The lack of selective breeding of mandarin fish in previous decades has resulted in a decline in the growth rate of pond-cultured fish, a shortened period of sexual maturity, and reduced disease resistance; these issues seriously affect the quality and safety of the fish products. The mandarin fish Siniperca chuatsi (Basilewsky) (order Perciformes, family Serranidae, subfamily Sinipercinae) is distributed in rivers of some East Asian countries, including China, Vietnam, and Korea [1]. As with many other cultured fish species, the lack of selective breeding of mandarin fish in previous decades has resulted in a decline in the growth rate of pond-cultured fish, a shortened period of sexual maturity, and reduced disease resistance; these issues seriously affect the quality and safety of the fish products [4]. It is necessary to establish a selective breeding program for the mandarin fish to improve the economical traits of the fish and to sustain the development of the mandarin fish industry
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
