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1.
The length‐weight relationships were determined for eight fish species [Zebrias zebra (Bloch, 1787); Zebrias quagga (Kaup, 1858); Amblyotrypauchen arctocephalus (Alcock, 1890); Gerres japonicus Bleeker, 1854; Apogonichthyoides pseudotaeniatus (Gon, 1986); Setipinna tenuifilis (Valenciennes, 1848); Bregmaceros rarisquamosus Munro, 1950; Bregmaceros nectabanus Whitley, 1941] belonging to six families. Fish samples were collected using gillnets (20 × 10 m, mesh size 0.5 cm) and cage net (200 × 10 × 15 cm, mesh size 0.5 cm) from mangroves of Guangdong, China. Samples were collected quarterly from June 2015 to March 2017.The allometric coefficient (b) of length‐weight relationship varied from 2.76 for Zebrias zebra to 3.38 for Setipinna tenuifilis. Length‐weight relationships for these 11 fish species were determined for the first time.  相似文献   

2.
Length–weight relationships were determined for three fish species (Cynoglossus macrolepidotus (Bleeker, 1851), Liparis tanakae (Gilbert & Burke, 1912), Zoarces elongatus (Kner, 1868)) from Bohai Sea (38°38′–40°28′N; 119°42′–121°10′E), China. Fish specimens were sampled monthly between May 1982 to May 1983 using pair bottom trawlers (150.5 × 96.5 m, mesh size: 30–200 mm) with a cod end (mesh size: 30 mm), which were towed at a ship's speed of two knots for 1 hr at a maximum depth of about 80 m. Relationships between length and weight were fitted very well for all species (all R2 > .90).  相似文献   

3.
The length–weight relationships (LWRs) for seven fish species belonging to five families in the Yangtze River Estuary and its adjacent waters are presented. Cynoglossus gracilis, Cynoglossus macrolepidotus, Ctenotrypauchen chinensis, Collichthys niveatus, Ophichthus apicalis and Erisphex potti were collected monthly in 2009 using trammel nets (the size of smaller mesh net was 1.5 m × 15 m × 4 panels with mesh sizes of 2.5, 3.4, 4.3 and 5.8 cm; the size of larger-mesh net was 2.4 m × 30 m × 4 panels with mesh sizes of 5.0, 6.0, 7.0 and 8.0 cm; soaking overnight). Lophiogobius ocellicauda were collected December in 2020 using shrimp trawl nets (mesh size 2.0 cm). The precision of measurement for the fish specimens is 0.1 cm total length and 0.1 g total weight. The estimated ranges of the parameters a and b for the seven fish species were from 0.0001 to 0.0289 and 2.718 to 3.541, respectively. Two new maximum total length were recorded for Ctenotrypauchen chinensis and Ophichthus apicalis.  相似文献   

4.
The present study provides length–weight relationship (LWR) of three fish species, Cynoglossus puncticeps (Richardson, 1846), Cynoglossus lingua Hamilton, 1822 and Cynoglossus lida (Bleeker, 1851) of family Cynoglossidae from Chilika lagoon (19°28′–19°54′N; 85°05′–85°38′E), India. A total of 147 specimens were sampled during March, July and October of 2017 from screen barrier nets (mesh 14 mm to 26 mm) locally called khonda jal operated by local fishermen. The estimated b values derived from the data sets as follows: 3.12 for C. puncticeps, 3.09 for C. lida, and 2.88 for C. lingua.  相似文献   

5.
The larval distribution and feeding habits of Cynoglossus abbreviatus and Cynoglossus lighti were investigated around the Rokkaku estuary in Ariake Bay during October 2004 and March and April 2005. Cynoglossus abbreviatus started and completed metamorphosis at larger sizes than C. lighti. Developmental phases consisted primarily of individuals at metamorphosis and postmetamorphosis, which were mainly distributed inside and just outside the Rokkaku River in March–April for C. abbreviatus and October for C. lighti. Tidal changes in vertical distribution just outside the river mouth differed between the closely related species; C. abbreviatus was distributed in the surface and middle layers at flood tide, and aggregated near the bottom (where the current speed was lowest) at ebb tide. Cynoglossus lighti stayed mainly near the bottom during all tidal phases. Larvae of both Cynoglossus species selectively fed on copepods (Pseudobradya sp.), which were scarce in the waters. These facts suggest that the nursery grounds of the two Cynoglossus species were different in terms of their tidal vertical distribution patterns.  相似文献   

6.
There are still only a few studies related to Bregmacerotidae larvae in Brazil, although these larvae are frequently collected in oceanic ichthyoplankton samples. Thus this study analyzes the occurrence and abundance of Bregmaceros larvae along the Brazilian central coast and describes larval characteristics. During three oceanographic cruises samples were collected between the Real River (12°S) and the São Tomé Cape (22°S). Oblique hauls were conducted from a maximum depth of 200 m, using bongo nets of 330‐ and 500‐μm mesh size. Among the 951 bregmacerotids collected, three species were identified corresponding to 89%Bregmaceros atlanticus, 8%Bregmaceros cantori and 3%Bregmaceros n. sp. B. atlanticus was widely distributed along the study area and was more frequent in stations situated beyond the 200‐m isobath; this species was more abundant during the winter, showing a peak of density between Vitória and the São Tomé Cape (355 larvae per 10 m2). Bregmaceros cantori densities were very similar during the three cruises; the highest value (25.6 larvae per 10 m2) was recorded during the winter and higher concentrations were observed in neritic stations along the 200‐m isobath. Bregmaceros n. sp. was rare in collections made during the three cruises; it was concentrated along the Bahia coast (12–18°S), and was more frequent in stations situated in the oceanic region. Bregmaceros atlanticus varying from 2.0 to 6.0 mm and Bregmaceros n. sp. larvae varying from 3.0 to 6.0 mm were present in all cruises, indicating that they spawn year‐round. Bregmaceros cantori did not show a distribution pattern among the different length classes, probably associated with the fact that this species has a coastal distribution.  相似文献   

7.
Yan Y R  Chen J L  Lu H S  Hou G  Lai J Y 《农业工程》2012,32(1):18-25
The monthly and ontogenetic variations in diet of hairtail Trichiurus margarites Li (1992) [20] (Perciformes, Trichiuridae) were examined in the Beibu Gulf of the South China Sea from October 2008 to September 2009. Stomachs of 666 hairtail ranging in size from 121 mm to 561 mm pre-anal length (PL) were sampled monthly from commercial fish catches. Fish were the primary prey, with Decapterus maruadsi (Perciformes, Carangidae) averaging 23% by number, 34% by weight, and 49% by Index of Relative Importance (IRI). Other important prey in the diet included the small benthic fish, Bregmaceros rarisquamosus and Bregmaceros nectabanus (Gadiformes, Bregmaceroridae) and the decapod shrimp, Acetes chinensis, with IRI percentages of 8%, 4%, and 3%, respectively. Low rates of cannibalism and predation on 30 additional species of prey were observed. Trophic diversity (Brillouin Index, Hz) was moderate throughout the year. Mean feeding intensity (Repletion Index, RI) varied considerably by month and increased with the gonad maturity stages of hairtail; conversely, the proportion of empty stomachs decreased with maturity stages, from 60.9% empty at Stage I to 41.6% empty at Stage VI. Prey weight and numbers differed significantly among the 14 PL size classes and increased with body size. Cluster analysis of prey IRI values also indicated differences in the feeding habits of hairtail by size class. Understanding the monthly and ontogenetic changes in hairtail diet may assist in the development and improvement of marine ecosystem modeling for the Beibu Gulf, South China Sea.  相似文献   

8.
The length–weight relationships of four fish species: Lophiomus setigerus (Vahl, 1797), Uranoscopus oligolepis Bleeker, 1878, Cynoglossus oligolepis (Bleeker, 1855), and Cynoglossus arel (Bloch & Schneider, 1801) were determined. Specimens were collected from the Beibu Gulf in the South China Sea by using bottom trawl nets (mesh size 4.0 cm, at a towing speed about 3 knots) in the seasonal investigations from August 2010 to May 2011. The values of parameter b of these four species ranged from 2.982–3.489 and remained within the normal range of 2.5–3.5.  相似文献   

9.
The scale morphology of pleuronectiforms in the Gulf of Oman remains insufficiently known. This study used light microscopy and morphological analysis to examine scale variation across the flank of four Tonguefishes species; Cynoglossus arel, C. bilineatus, C. lingua, and C. puncticeps. Scales were extracted from six flank regions, three on the eyed and blind sides, respectively. The most differentiated species was C. arel, which showed significant differences in four size variables in five regions. In Cynoglossus arel and C. lingua, the scales of the eyed side were ctenoid, and those scales from the blind side were cycloid; C. puncticeps have ctenoid scales on both flank sides and C. bilineatus has cycloid scales on both sides. All species' scales on the blind side have fewer ctenial spines (except in C. bilineatus). This study indicated that scale morphology demonstrated considerable variation among the flank regions of the examined species. As a result, the scales from the head and the trunk regions of the eyed side and the scales from the head region of the blind side have a good power of species separation in this family.  相似文献   

10.
Spatiotemporal occurrence and feeding habits of tonguefish (Cynoglossus lighti Norman, 1925) larvae were investigated in an offshore area (>5 m in depth) of the inner part of Ariake Bay, Japan. All specimens were symmetric, free‐swimming larvae. Although their seasonal abundance and distribution in the study site varied from year to year, spawning started in June and the larval abundance was high in August and September with a wide distribution in the inner part of the bay. Both present and previous study results strongly suggest that larvae may settle primarily in the estuary and near‐shore areas of Ariake Bay after their wide distribution in the offshore area of the bay during the free‐swimming stage. Larvae showed a clear feeding rhythm in which they fed on prey mainly during the daytime. Larvae fed exclusively on copepods, and identified prey were mostly Paracalanidae (mainly Parvocalanus crassirostris), Microsetella norvegica, and Oithona davisae. Pre‐metamorphosis larvae fed primarily on Paracalanidae and O. davisae, whereas O. davisae formed a smaller proportion of the early‐metamorphosis diet. In early metamorphoses, larvae fed preferentially on Paracalanidae and M. norvegica.  相似文献   

11.
The length–weight relationships (LWRs) for six little‐known fish species collected in the northern Persian Gulf (south of Iran) are presented, namely, Plicofollis dussumieri, Pseudotriacanthus strigilifer, Cynoglossus bilineatus, Cynoglossus arel, Solea elongata, and Pseudorhombus elevates.  相似文献   

12.
Length-weight relationships (LWRs) were estimated for 11 fish species from the Min River Estuary and its adjacent waters, Fujian Province, China. All samples were collected using gillnets (mesh size 45 mm) and bottom trawls (mesh sizes 45 mm at the main webbing and 25 mm at the cod end) seasonally in 2017 and 2018. The parameters for the LWRs were estimated, along with the basic Statistical analyses for total length and weight ranges as well as the 95% confidence intervals for the intercept (a) and the slope (b) of the regression lines. Further, the coefficient of correlation indicated that the LWRs were highly significant (all r2 > .95, p < .001). This study provides the new maximum total lengths (TLmax) for Coilia grayii (33.0 cm), Johnius taiwanensis (20.9 cm), Johnius trewavasae (22.0 cm) and Cynoglossus sibogae (22.0 cm).  相似文献   

13.
Two microsatellite‐enriched libraries [(CAGA)n, (TAGA)n] were constructed using pooled DNA from three cyprinid species native to the Sacramento–San Joaquin Delta of California: Sacramento splittail (Pogonichthys macrolepidotus); Sacramento pikeminnow (Ptychocheilus grandis); and tui chub (Siphateles bicolor). Primers were designed for 105 loci and tested for levels of polymorphism in five cyprinid species found in the Delta: Sacramento splittail, Sacramento pikeminnow, tui chub, hitch (Lavinia exilicauda), and Sacramento blackfish (Orthodon microlepidotus). Fifty‐one loci were polymorphic for at least one species and 31 loci were polymorphic for multiple species. The number of polymorphic loci per species ranged from 16 to 26.  相似文献   

14.
This study provides length–weight relationships (LWRs) for three flatfish species: Cynoglossus bilineatus (Lacepède, 1802), Solea elongata (Day, 1877), and Pseudorhombus elevatus (Ogilby, 1912) from Motaf fishing grounds (latitude 27°00′ to 28°03′N; longitude 51°41′ to 52°11′E), Bushehr province, Iran. A total of 103 fish specimens were collected using shrimp trawler with 40 mm (stretched mesh size) at depths of 10–30 m between August and September 2017. The LWRs for fish species were W = 0.0019L3.353 for C. bilineatus: W = 0.0093L3.174 for S. elongata, and W = 0.006L3.181 for P. elevatus, respectively.  相似文献   

15.
Length–weight relationships were estimated for 14 species belonging to 13 fish families from the Suer River estuary, Korea. These 14 species are: Callionymus valenciennei, Konosirus punctatus, Conger myriaster, Cynoglossus joyneri, Tribolodon hakonensis, Thryssa hamiltonii, Acanthogobius flavimanus, Paratrypauchen microcephalus, Hexagrammos agrammus, Nuchequula nuchalis, Pseudopleuronectes yokohamae, Pennahia argentata, Sillago japonica and Takifugu niphobles. Between April 2009 and January 2010, samples were caught by commercial trawl net at depths of <20 m. Estimates for parameter b of the length–weight relationship (W = aLb) ranged between 2.510 and 3.149.  相似文献   

16.
《Chirality》2017,29(3-4):147-154
Separations of six dihydropyridine enantiomers on three commercially available cellulose‐based chiral stationary phases (Chiralcel OD‐RH, Chiralpak IB, and Chiralpak IC) were evaluated with high‐performance liquid chromatography (HPLC). The best enantioseparation of the six chiral drugs was obtained with a Chiralpak IC (250 × 4.6 mm i.d., 5 μm) column. Then the influence of the mobile phase including an alcohol‐modifying agent and alkaline additive on the enantioseparation were investigated and optimized. The optimal mobile phase conditions and maximum resolution for every analyte were as follows respectively: n‐hexane/isopropanol (85:15, v /v) for nimodipine (R  = 5.80) and cinildilpine (R  = 5.65); n‐hexane/isopropanol (92:8, v /v) for nicardipine (R  = 1.76) and nisoldipine (R  = 1.92); and n‐hexane/isopropanol/ethanol (97:2:1, v /v/v) for felodipine (R  = 1.84) and lercanidipine (R  = 1.47). Relative separation mechanisms are discussed based on the separation results, and indicate that the achiral parts in the analytes' structure showed an important influence on the separation of the chiral column.  相似文献   

17.
The composition of oil samples isolated from needles of Pinus halepensis growing in three locations in Corsica (Saleccia, Capo di Feno, and Tre Padule) has been investigated by combination of chromatographic (GC with retention indices) and spectroscopic (MS and 13C‐NMR) techniques. In total, 35 compounds that accounted for 77 – 100% of the whole composition have been identified. α‐Pinene, myrcene, and (E)‐β‐caryophyllene were the major component followed by α‐humulene and 2‐phenylethyl isovalerate. Various diterpenes have been identified as minor components. 47 Oil samples isolated from pine needles have been analyzed and were differentiated in two groups. Oil samples of the first group (15 samples) contained myrcene (M = 28.1 g/100 g; SD = 10.6) and (E)‐β‐caryophyllene (M = 19.0 g/100 g; SD = 2.2) as major components and diterpenes were absent. All these oil samples were isolated from pine needles harvested in Saleccia. Oil samples of the second group (32 samples) contained mostly (E)‐β‐caryophyllene (M = 28.7 g/100 g; SD = 7.9), α‐pinene (M = 12.3 g/100 g; SD = 3.6), and myrcene (M = 11.7 g/100 g; SD = 7.3). All these oil samples were isolated from pine needles harvested in Capo di Feno and Tre Padule.  相似文献   

18.
This study estimated the LWRs of six fishes from the coastal waters of Greater Accra, Ghana. Data was obtained monthly from June 2018 to July 2019 and analyzed for total length and weight measurement to the nearest 0.1 cm and 0.01 g respectively. The sampling was done using hooks and line as well as monofilament and multifilament gear types. The mesh sizes for both monofilament and multifilament gear types ranged from 0.5 to 2 inches whereas the hooks types ranged from 6 to 12. The b values for the assessed species were within the range 2.8–3.2. There was strong correlation between the length and weight of all the species (R2 > .95). This study provides LWRs for Cynoglossus senegalensis, Scorpaena histrio and Pseudotolithus senegalensis and larger maximum total length (TLmax) for Syacium micrurum, Eucinostomus melanopterus and Brachydeuterus auritus.  相似文献   

19.
Length‐weight relationships (LWRs) were evaluated for three endemic fish species (Sinibrama taeniatus Nichols, 1941; Ancherythroculter nigrocauda Yin & Wu, 1964; and Acrossocheilus monticola Günther, 1888) from the upper reaches of the Yangtze River, southwestern China. Samples were collected using gill nets (25 × 12 m, mesh‐size 2.0 cm) and fishing cages (0.5 × 0.5 × 10 m, mesh‐size 1.0 cm) as well as by electroshock (CWB‐2000 P, 12 V, 250 Hz), from July to September in 2013–2016. Prior to this study, the LWRs for these three species (S. taeniatus, A. nigrocauda and A. monticola) were unknown. In addition, new maximum size for A. nigrocauda and A. monticola were provided.  相似文献   

20.
The single nucleotide polymorphisms (SNPs) in the BUD13 homolog (BUD13) and zinc finger protein 259 (ZNF259) genes have been associated with one or more serum lipid traits in the European populations. However, little is known about such association in the Chinese populations. Our objectives were to determine the association of the BUD13/ZNF259 SNPs and their haplotypes with hypercholesterolaemia (HCH)/hypertriglyceridaemia (HTG) and to identify the possible gene–gene interactions among these SNPs. Genotyping of 6 SNPs was performed in 634 hyperlipidaemic and 547 normolipidaemic participants. The ZNF259 rs2075290, ZNF259 rs964184 and BUD13 rs10790162 SNPs were significantly associated with serum lipid levels in both HCH and non‐HCH populations (P < 0.008–0.001). On single locus analysis, only BUD13 rs10790162 was associated with HCH (OR: 2.23, 95% CI: 1.05, 4.75, P = 0.015). The G‐G‐A‐A‐C‐C haplotype, carrying rs964184‐G‐allele, was associated with increased risk of HCH (OR: 1.35, 95% CI: 1.10, 1.66, P = 0.005) and HTG (OR: 1.75, 95% CI: 1.39, 2.21, P = 0.000). The A‐C‐G‐G‐C‐C and A‐C‐A‐G‐T‐C haplotypes, carrying rs964184‐C‐allele, were associated with reduced risk of HCH (OR: 0.77, 95% CI: 0.61, 0.99, P = 0.039 and OR: 0.66, 95% CI: 0.47, 0.94, P = 0.021 respectively). On multifactor dimensionality reduction analyses, the two‐ to three‐locus models showed a significant association with HCH and HTG (P < 0.01–0.001). The BUD13/ZNF259 SNPs, which were significant in the European populations, are also replicable in the Southern Chinese population. Moreover, inter‐locus interactions may exist among these SNPs. However, further functional studies are required to clarify how these SNPs and genes actually affect the serum lipid levels.  相似文献   

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