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1.
The length–weight relationships of 13 species from river Nestos (North Greece) were calculated in the present study, seven of which are presented for the first time. Significant length–weight relationships with high correlation coefficient were found for all species. The value of the parameter b varied between 2.36 and 3.27 (mean value ± SE: 3.05 ± 0.06).  相似文献   

2.
Length–length and length–weight relationships can vary temporally and spatially, so it is imperative that accurate estimates of these relationships are available. Total length–standard length (TL‐SL) and standard length–total weight (SL–TW) relationships were calculated for eight species of drum (Sciaenidae) occurring in estuaries of southeastern Louisiana. Data were derived from monthly trawl, beach seine, and gillnet collections taken in and around Lake Pontchartrain between 2000 and 2012. Overall TL–SL relationships (ignoring the month) were found for seven species and overall SL–TW relationships were found for eight species. The strong r2 values (all > 0.950, except for one instance) indicate that these relationships are robust and will be appropriate for use by scientists managing these species.  相似文献   

3.
We present 54 weight–length relationships pertaining to 36 fish species, caught in the Greek part of the River Strymon system (northern Greece). The total weight (W) – total length (TL) relationships were estimated using the logarithmic form of the equation W = aTLb. The exponent b ranged between 2.34 and 3.95, (mean ± SE: 3.16 ± 0.044). For 5 out of the 36 species weight–length parameters are presented for the first time.  相似文献   

4.
Length–weight relationships for six deep‐sea fish species inhabiting the shelf regions of the western Bay of Bengal and the waters of Andaman and Nicobar of India are presented. Samples were collected using high‐speed demersal trawl and expo demersal trawl nets at depths of 231–514 m in August and September 2010. The b values in the analyses ranged from 3.05 to 3.31, showing a mean and median value of 3.21 (SE ± 0.039, SD ± 0.097) and 3.2, respectively. Comparisons of b values with earlier estimations confirm the presence of spatial and temporal variations in the length–weight relations among the species. Coefficient of determination scores ranged from 0.94 to 0.97, indicating robustness of the samples analysed. This study provides the first estimates of length–weight relationships for four of the deep‐sea fishes, enriching the understanding of the growth patterns and population dynamics of these less‐studied deep‐sea fishery resources in Indian Ocean waters.  相似文献   

5.
The study presents length–weight relationships (LWRs) and length–length relationships (LLRs) for three algae‐scraper species; Capoeta coadi from the Kouhrang River (Iran; 32°23′N, 50°08′E) a part of the Tigris drainage basin, Capoeta pyragyi from Cheshmeh Langan River (32°55′N, 50°10′E) a part of Zayanderud River basin and Capoeta umbla from Chooman River (35°57′N, 45°47′E). Fish were sampled by electro fishing (Samus1000; Power Out: 200 watts) in August, September and October 2017. Sampling was carried out each months in sites covering an area of about 100 m2 including runs, riffles and pools at a water depth of 10–60 cm. The obtained LWRs and LLRs showed a high level of correlation (r> 0.99).  相似文献   

6.
Length–weight and length–length parameters were calculated for seven fish species belonging to five families in the Zohreh River, Iran. The weight–length relationships were estimated using the equation W = aLb. The b values varied between 2.72 and 3.33, with a mean ± SD of 2.88 ± 0.28. The b values parameter in the length–weight relationship equations were calculated as 3.15 for Alburnus mossulensis Heckel, 1843; 3.78 for Barilius mesopotamicus Berg, 1932; 2.86 for Cyprinion macrostomum Heckel, 1843; 2.89 for Nuchequula gerreoides (Bleeker, 1851); 2.80 for Mastacembelus mastacembelus (Banks & Solander, 1794); 2.72 for Liza abu (Heckel, 1843); and 3.19 for Paraschistura nielseni (Nalbant and Bianco, 1998). This study presents the first LWR and LLR references for these species in the Zohreh River.  相似文献   

7.
This study describes length–weight (LWR) and length–length relationships (LLR) of bluefin tuna (BFT), Thunnus thynnus, in the eastern Mediterranean (Levantine Sea). Fulton’s condition factor (K) was also calculated for each standard length class for both sexes. A total of 363 specimens, 175 males and 188 females, were caught by purse‐seine from late winter to early summer 2003 off Antalya Bay, Turkey. Fork length values of 175 BFT males were between 114 and 250 cm with an average of 159.3 cm ± 2.14, and between 116 and 256 cm with an average of 163 cm ± 2.26 in 188 females. LWRs indicated positive allometric growth in both males and females. The coefficient b ranged from a minimum 3.32 for males to a maximum of 3.35 for females. Results indicated that the LLRs were highly correlated (r2 > 0.99, P < 0.001). K values ranged from 1.45 to 2.11 (mean: 1.56 ± 0.12) in males and from 1.43 to 2.14 (mean: 1.69 ± 0.06) in females.  相似文献   

8.
Length‐weight and length‐length relationships were investigated for 13 freshwater fish species from the lower Jinsha River, southwest China (from 101°32′49.63″E; 26°35′38.27″N to 104°37′48.14″E; 28°45′59.55″N). Fish were sampled from five sites during 2014 and 2016, using trap‐nets, gillnets (major mesh size: 2–6 cm), longline and electrofishing. Length‐weight relationships for six and length‐length relationships for 12 species are the first report to FishBase, respectively. Moreover, new maximum length for 11 species are also presented to FishBase in this study. All regressions were highly significant (< .001), with the coefficient of determination r> .950. These information will be helpful for management and conservation in local fishes and fisheries.  相似文献   

9.
Oilfish, escolar, snake mackerel (order Aulopiformes, family Gempylidae), and longnose lancetfish (order Perciformes, family Alepisauridae) sampled from the western North Atlantic and the Gulf of Mexico were analyzed for length–weight and length–length relationships. These species are encountered as occasional bycatch of pelagic longline fisheries. The fish (161 specimens, 19.0–149.1 cm TL) were collected over a 3‐year period (January 2007–January 2010) from pelagic longline gear targeting swordfish and tuna. For each species, 95% confidence limits (CI) of parameters b and log a and regression coefficients (r2) were calculated for log‐transformed length–weight relationships. The length–weight parameter b for all species ranged from 2.881 to 3.358, with regression coefficients (r2) ranging from 0.75 to 0.98. Linear relationships between fork lengths, standard lengths, and total lengths were also calculated.  相似文献   

10.
The length–weight relationships for 10 freshwater fish species from an intermittent river basin in a semi‐arid region of Brazil were analyzed. Specimens were caught using a dragnet (3.5 × 2.5; stretched mesh size 5 mm) during running and pool phases from January to November 2015. The specimens were measured for total length and weight. Previously unavailable in FishBase, the detailed length–weight relationships of Compsura heterura, Phenacogaster calverti, and Serrapinnus piaba are reported for the first time. All fish collected presented total lengths (TL) lower than the maximum reported in FishBase.  相似文献   

11.
The relationships of total length (TL), fork length (FL) and standard length (SL) are presented for four fish species and the relationships between TL and wet weight for 23 fish species from the Chi River in northeastern Thailand. All length–length relationships were linear (r2 > 0.95). Slope (b) of the length–weight relationships showed values between 2.5073 and 3.4896.  相似文献   

12.
A flow‐injection (FI) method is reported for the determination of Mn(II), maneb and mancozeb fungicides based on the catalytic effect of Mn(II) on the oxidation of lucigenin and dissolved oxygen in a basic solution. The Tween‐20 surfactant has been reported for first time to enhance lucigenin chemiluminescence (CL) intensity in the presence of Mn(II) (53%) and maneb and mancozeb (89%). The calibration graphs were linear in the concentration range of 0.001–1.5 mg L–1 (R2 = 0.9982 (n = 11) with a limit of detection (S/N = 3) of 0.1 µg L–1 for Mn(II) and 0.01–3.0 mg L–1 [R2 = 0.9989 and R2 = 0.9992 (n = 6)] with a limit of detection (S/N =3) of 1.0 µg L–1 for maneb and mancozeb respectively. Injection throughputs of 90 and 120 h–1 for Mn(II) and maneb and mancozeb respectively, and relative standard deviations of 1.0–3.4% were obtained in the concentration range studied. The experimental variables, e.g., reagents concentrations, flow rates, sample volume, and photomultiplier tube voltage, were optimized and potential interferences were investigated. The analysis of Mn(II) in river water reference materials (SLRS‐4 and SLRS‐5) showed good agreement with the certified values incorporating an on‐line 8‐hydroxyquinoline chelating column in the manifold for removing interfering metal ions. Recoveries for maneb and mancozeb were in the range of 92 ± 5 to 104 ± 3% and 91 ± 2 to 100 ± 4% (n = 3) respectively. The effect of 30 other pesticides (fungicides, herbicides and insecticides) was also examined in the lucigenin–Tween‐20 CL system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

13.
This study determined the length–weight relationships (LWRs) and length–length relationships (LLRs) of seven freshwater fish from the Daning River, a tributary of the Yangtze River, southwest China. Specimens were collected between July 2016 and July 2017 using drift gill nets (mesh size 1, 2 and 3 cm), cage net (0.5 cm mesh size) and electroshock fishing techniques quaterly. Parameter b values of LWRs ranged from 2.647 to 3.276 (r2 > .963) and b values of LLRs ranged from 1.091 to 1.213(r2 > .985). Six new LLRs and seven new maximum length data are presented. The biometric data and their relationships are relevant to Fishers science to supplement other data sets needed for fisheries management.  相似文献   

14.
The Lake Eyre Basin in central Australia is one of the world's last unregulated dryland river systems. To facilitate future research in this area, the relationships between total length, standard length, and wet weight for 10 widespread, large‐bodied freshwater fish species are presented. All linear relationships were strong (r2 > 0.90) and values of the exponent b of the length–weight relationships ranged from 2.786 to 3.336. These results provide novel baseline data for species in this area.  相似文献   

15.
Length–weight relationships (LWRs) of 139 coral reef and pelagic fish species (representing 34 fish families) were calculated based on 3806 individuals measured at local fish markets near the Davao Gulf in the southern Philippines during weekly visits between March 2009 and July 2011, as well as in June 2012. Fishes were caught with a variety of fishing methods, corroborated by abrasions and injuries. Forty‐seven of 139 LWRs were firstly reported and new to science. The mean slope b of the LWRs was 3.035, indicating that the majority of studied species followed isometric growth. Standard length – total length relationships were calculated for all measured fish species. Additionally, standard length – fork length relationships are presented for 108 species. Moreover, fifteen new records of maximum fish length and weight are reported.  相似文献   

16.
The present study provides the length–weight relationships (LWRs) of 13 fish species belonging to eight families that were collected in Rongcheng Bay, March 2009 to December 2014. The r2 values ranged from 0.953 to 0.994 and values of b varied from 2.542 to 3.454. The study also describes the total length – standard length relationships (LLRs) for these fish species. This is the first record of length–weight and length–length relationships for the fish species in this area.  相似文献   

17.
It is generally accepted that hypertension and other vascular pathologies increase in diabetes mellitus (DM) patients as a result of the renin–angiotensin–aldosterone (RAA) system. In this study, changes in the renin‐angiotensin‐aldosterone (RAA) system level was determined in Streptozotocin (STZ)‐injected rats. A total of 46 female Wistar albino rats (180–220 g body weight) was utilized in these experiments. STZ was given intraperitoneally to induce diabetes in rats. Streptozotocin (60 mg kg−1 body weight) was dissolved in 0·1 m citrate–‐phosphate buffer (pH 4–5). The non‐diabetic rats were injected with sterilized buffer alone to act as a control group. Blood glucose levels were 398±8·2 mg dl−1, 488±11·75 mg dl−1 and 658±29·6 mg dl−1 at days 3, 12 and 30 respectively. The level of plasma renin activity (PRA) was measured as 7·69±1·07 ng ml−1 h−1; 1·82±0·22 ng ml−1 h−1 and 0·67±0·12 ng ml−1 h−1 at days 3, 12 and 30, respectively. These values showed that the PRA levels are decreased with increased time period. Serum angiotensin converting enzyme (ACE, E.C. 3.4.15.1) levels were increased at days 12 and 30 (p<0·05 and p<0·005), whereas serum aldosterone levels were increased at days 3 and 12 (p<0·05). The level of urea and creatinine increased at days 12 and 30 (p<0·05 and p<0·005, respectively) when compared to the control group. The data from these experiments indicate that the PRA level decreased whereas ACE activity level increased in diabetic rats compared with the control. Aldosterone levels increased at the first stage of the experiment, but then decreased by the end of the experiment as a result of changes in renin and ACE levels. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

18.
This study describes the length–weight and length–length relationships for three cyprinid species from the Bibi‐Sayyedan River (western Isfahan provinces, Iran). The slope parameter (b) values in the length–weight relationship equations were determined as 3.0729 for Alburnus mossulensis Heckel, 1843; 2.8509 for Barbus lacerta Heckel, 1843; and 3.0864 for Chondrostoma regium (Heckel, 1843). This study presents the first LWR and LLR references for these species in the Bibi‐Sayyedan River.  相似文献   

19.
The z‐average mean‐square radius of gyration 〈S2z, the particle scattering function P(k), the second virial coefficient, and the intrinsic viscosity [η] have been determined for amylose tris(phenylcarbamate) (ATPC) in methyl acetate (MEA) at 25°C, in ethyl acetate (EA) at 33°C, and in 4‐methyl‐2‐pentanone (MIBK) at 25°C by light and small‐angle X‐ray scattering and viscometry as functions of the weight‐average molecular weight in a range from 2 × 104 to 3 × 106. The first two solvents attain the theta state, whereas the last one is a good solvent for the amylose derivative. Analysis of the 〈S2z, P(k), and [η] data based on the wormlike chain yields h (the contour length or helix pitch per repeating unit) = 0.37 ± 0.02 and λ?1 (the Kuhn segment length) = 15 ± 2 nm in MEA, h = 0.39 ± 0.02 and λ?1 = 17 ± 2 nm in EA, and h = 0.42 ± 0.02 nm and λ?1 = 24 ± 2 nm in MIBK. These h values, comparable with the helix pitches (0.37–0.40 nm) per residue of amylose triesters in the crystalline state, are somewhat larger than the previously determined h of 0.33 ± 0.02 nm for ATPC in 1,4‐dioxane and 2‐ethoxyethanol, in which intramolecular hydrogen bonds are formed between the C?O and NH groups of the neighbor repeating units. The slightly extended helices of ATPC in the ketone and ester solvents are most likely due to the replacement of those hydrogen bonds by intermolecular hydrogen bonds between the NH groups of the polymer and the carbonyl groups of the solvent. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 729–736, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com  相似文献   

20.
Length–weight relationships (LWRs) were determined for seven riverine fish species from the river Ganga, India. Specimens were collected on a bi‐monthly basis from April 2017 to December 2018 using gill nets (mesh size 22–34 mm), cast nets (mesh size 16 mm) and bag nets (mesh size 14–22 mm). Total length was measured to the nearest 0.1 cm using a digital caliper and weight was recorded to the nearest 0.01 g on an electronic balance. From estimated length–weight relationships, the values for parameter “a” ranged from 0.004 (Bregmaceros mcclellandi and Setipinna tenuifilis) to 0.014 (Brachirus pan). Likewise, the values for the parameter “b” of the equation ranged from 2.958 (Bagarius bagarius) to 3.124 (Bregmaceros mcclellandi) and r2 from 0.978 (Gonialosa manmina) to 0.996 (Brachirus pan).  相似文献   

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