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1.
This study investigates length–weight and length–length relationships of four shad species (Alosa caspia caspia, Alosa immaculata, Alosa maeotica, Alosa tanaica) captured in the western Black Sea coast of Turkey. A total of 686 specimens, 355 females and 331 males, were caught by gill net, trammel net and longline from 2006 through 2007 along the western Black Sea coast of Turkey. The relationships of total length (TL), fork length (FL) and standard length (SL) are presented for inhabiting in the Black Sea four shad species and the relationships between total length (TL) and body weight (BW) from the two localities, Sile and Karasu in the western Black Sea coast of Turkey. The Length–weight relationships generally indicated positive allometric growth in Alosa species for both males and females and an isometric growth for A. immaculata females. The coefficient b ranged from a minimum 2.97 for females of A. immaculata to a maximum 3.75 for both sexes A. c. caspia. Results indicated that the length–length relationship between the three length measurements were highly correlated (r2 > 0.99, P < 0.001).  相似文献   

2.
Relationships between fish and otolith measurements were analyzed in nine demersal fishes from the north‐eastern Tasmanian waters: Foetorepus calauropomus, Trachurus declivis, Parequula melbournensis, Neosebastes scorpaenoides, Platycephalus aurimaculatus, Platycephalus bassensis, Platycephalus conatus, Lepidotrigla mulhalli and Lepidotrigla vanessa. The values of exponent b from the relationships between fish weight and fish total length, total length and otolith length, total length and otolith width, and fish weight and otolith length were estimated. All above relationships were statistically significant. The analysis of covariance (ANCOVA) was used to test the effect of the categorical factor of species in the fish length and otolith length relationship. Significant differences in fish length and otolith length relationship between species were highlighted in both gurnards and flatheads. Results from this study will provide novel information on quantitative biometric relationships between body and otolith measurements of fish species in Australian waters.  相似文献   

3.
The present study estimated the a and b parameters of the weight‐length relationship of five fish species that inhabit the tidal creeks of islands in the Amazon estuary: Colomesus asellus, Geophagus proximus, Lithodoras dorsalis, Pseudauchenipterus nodosus, Pachypops fourcroi. The species were collected quarterly between October 2013 to July 2014 using block nets made from 20 mm mesh size. The b coefficient of the regression of the weight on the total length of these species ranged from 2.71 to 3.14. These are the first reference on the weight‐length relationship for three species and the new maximum length recorded for two species.  相似文献   

4.
Length‐weight relationships of three sympatric species of stingrays from a coastal mudflat, Malaysia were estimated. A total of 290 individuals (150 Himantura walga, 78 Dasyatis bennetti, and 57 Dasyatis zugei) were sampled using barrier net, gill net and beam trawl. The length‐weight relationship based on disc length and width generally showed positive allometric growth (b > 3) for all species. This study reports the first findings regarding the length‐weight relationships of these stingray species in Malaysian waters.  相似文献   

5.
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   

6.
The present study investigates the length‐weight relationship and condition factor of populations of the Indo‐Pacific fish Terapon jarbua ( Forsskål, 1775 ) collected in the wider Gulf of Aden, notably from Socotra Island and the Hadramout coast of Yemen. This region displays a monsoon climate, with wide seasonal variations affecting estuarine habitats. A total of 620 specimens collected in estuaries and at sea were measured and weighed during field surveys carried out in 2007 and 2008 during pre‐ and post‐ South‐Western monsoon periods. The length‐weight relationship of the studied populations of Terapon jarbua was determined as W = 0.0288 × SL2.99, with r2 = 0.96 and consistent with existing data on the species from other regions. Significant seasonal differences were found in Fulton’s condition factor of Terapon jarbua.  相似文献   

7.
The length‐weight relationships were determined for three fish species [Glyptothorax dorsalis Vinciguerra, 1890, Glyptothorax zanaensis Wu, He & Chu, 1981, and Percocypris tchangi (Pellegrin & Chevey, 1936)]. All fish were collected using drift gillnet (stretched mesh size: 4 cm) and castnet (mesh size: 1 cm) from Gongshan mountain, China. Samples were collected quarterly from July 2014 to August 2016. The parameter b of length‐weight relationship varied from 2.51 for Glyptothorax dorsalis to 3.30 for Percocypris tchangi. And the new standard length recorded for Glyptothorax dorsalis and Percocypris tchangi.  相似文献   

8.
Length–weight relationships were estimated for six teleost fish species occurring in Bijagós Archipelago, Guinea‐Bissau. Samples were collected seasonally during three dry seasons (2013/2014, 2014/2015, 2015/2016) and two rainy seasons (2015 and 2016). Fishes were captured by three methods: angled from the beach or a boat; using beach seine with a mesh size ranging 0.5–1 cm; drift netting from a boat (mesh size 2 cm). This work provides the length‐weight relationship for three fish species that are not reported in FishBase (Citharichthys stampflii, Gerres nigri and Psettodes belcheri) as well as for three species from which we present a wider size range (Eucinostomus melanopterus, Scomberomorus tritor and Sphyraena afra).  相似文献   

9.
This study provides the total length–weight relationships (LWRs) for five fish species collected from the Nujiang River, southwest China. Samples were obtained in May 2015 and May 2016 using drift net and electroshock fishing techniques. A total of 502 specimens belonging to five fish species were analyzed; their LWRs were calculated. The five fish were Schizothorax nukiangensis, Akrokolioplax bicornis, Creteuchiloglanis kamengensis, Channa gachua and Glyptothorax trilineatus. Prior to this study, the length‐weight relationship for S. nukiangensis is unknown to FishBase and new maximum lengths are recorded for A. bicornis and C. kamengensis.These results are useful for fishery research, conservation and management in the Nujiang River.  相似文献   

10.
Length‐weight relationship (LWR) was estimated for three fish species from the northern coast of Yucatan peninsula in the Gulf of Mexico. All specimens were monthly collected from September 2015 to October 2016 by recreational fishing (handlining). A total of 408 individuals (15 Calamus campechanus, 9 Opsanus beta and 384 Sphoeroides nephelus) were sampled and analyzed. Information regarding LWR data for one of these species were not yet available in FishBase database, two of them have limited data and a new record of maximum length is presented.  相似文献   

11.
Length‐weight relationships were estimated for five Triplophysa species from the northwest China. A total of 1,598 specimens were collected using set gillnets (mesh size 1.5 cm) and ground bamboo cages in May 2012, and August 2014. This study presents the first references on LWRs for Triplophysa minuta, T. siluroides, and T. tenuis, and two new maximum length records for T. yarkandensis and T. strauchii. Statistical length–weight relationships for all five species were highly significant (p < .001), with R2 values >.915.  相似文献   

12.
Z. Tan  K. Xing  T. Yang  Y. Pan  Y. Wang  S. Mi  D. Sun  C. Wang 《Animal genetics》2018,49(2):127-131
Using the PorcineSNP80 BeadChip, we performed a genome‐wide association study for seven reproductive traits, including total number born, number born alive, litter birth weight, average birth weight, gestation length, age at first service and age at first farrowing, in a population of 1207 Large White pigs. In total, we detected 12 genome‐wide significant and 41 suggestive significant SNPs associated with six reproductive traits. The proportion of phenotypic variance explained by all significant SNPs for each trait ranged from 4.46% (number born alive) to 11.49% (gestation length). Among them, 29 significant SNPs were located within known QTL regions for swine reproductive traits, such as corpus luteum number, stillborn number and litter size, of which one QTL region associated with litter size contained the ALGA0098819 SNP for total number born. Subsequently, we found that 376 functional genes contained or were near these significant SNPs. Of these, 14 genes—BHLHA15, OCM2, IL1B2, GCK, SMAD2, HABP2, PAQR5, GRB10, PRELID2, DMKN, GPI, GPIHBP1, ADCY2 and ACVR2B—were considered important candidates for swine reproductive traits based on their critical roles in embryonic development, energy metabolism and growth development. Our findings contribute to the understanding of the genetic mechanisms for reproductive traits and could have a positive effect on pig breeding programs.  相似文献   

13.
The life history characteristics of Aristotle’s catfish, Silurus aristotelis (Agassiz 1856) were studied in Lake Pamvotis (northwestern Greece). Samples were collected on a monthly basis using gillnets, trammel‐nets and traps. Total lengths ranged from 11.1 to 36.7 cm. Sex ratio was biased toward females (F : M = 1.8 : 1) and was statistically different from unity (χ2 = 46.94, P < 0.001). Spawning is from April to June. The relationship between total length and total weight showed positive allometric growth for males (TW = 0.0035 × TL3.21, r2 = 0.93, n = 198, P < 0.001) and females (TW = 0.0066 × TL3.02, r2 = 0.95, n = 363, P < 0.001). Age was determined on the annual growth marks formed on the spine of the pectoral fin. Based on cross‐section readings of the spine, lifespan of the Aristotle’s catfish was 5 years. Age classes 1 and 2 dominated the catches (39.1 and 40.0% of the total sample, respectively). Back‐calculated lengths at age showed a rapid increase in fish size during the first year of life, reaching 61.1% of maximum attainable length, and a declining growth rate thereafter. Growth parameters were calculated as L = 36.12 cm, K = 0.37 year?1, t0 = ?0.76 year based on the observed lengths at age and as L = 28.19 cm, K = 0.53 year?1, t0 = ?0.62 year based on the back‐calculated lengths at age. It seems that some of the life history traits (longevity, growth pattern, reproductive period) are influenced significantly by adverse effects of pollution and eutrophication on the lacustrine ecosystem.  相似文献   

14.
The length‐weight relationships (LWRs) are presented for eight freshwater fish species (Acheilognathus macropterus, Saurogobio dabryi, Saurogobio gymnocheilus, Sinobdella sinensis, Pelteobagrus eupogon, Rhinogobius cliffordpopei, Neosalanx jordani, and Silurus meridionalis) from the Yangtze River and Lake Taihu. A total of 1044 specimens were sampled and measured between July 2012 and June 2014. Among the eight species, five species have no LWR estimates in FishBase.  相似文献   

15.
Weight‐for‐length during the early postnatal period is a critical predictor of subsequent body composition and metabolic risk. This study was designed to analyze change in weight‐for‐length status according to birth weight in early infancy. Data were collected for 267 infants enrolled in the Jackson County Women, Infants, and Children (WIC) program. Postnatal measurements were collected at a clinic visit between birth and 12 weeks of age (mean = 5.7 weeks). Changes inWHO z‐scores (weight, length, weight‐for‐length) between birth and the clinic visit were calculated. Infants were classified as exclusively breastfed or as formula‐fed. Ethnicity was coded as Hispanic or non‐Hispanic. Infants were classified based on birth weight z‐score as lower ( +1 SD). Multiple regression models tested birth weight, demographic factors, and feeding as predictors of z‐score change measures. Demographic factors and feeding were also tested as moderators of the effects of birth weight. Lower birth weight infants displayed an increase in weight‐for‐length z‐score between birth and the clinic visit. Change in weight‐for‐length was associated with significant increase in weight z‐score but not in length z‐score. Higher birth weight predicted decrease in weight and length z‐scores but did not predict change in weight‐for‐length. Hispanic ethnicity predicted decrease in length z‐score and increase in weight‐for‐length z‐score but did not moderate effects of birth weight. Increase in weight‐for‐length among lower birth weight infants and persistence of high weight‐for‐length among higher birth weight infants may reflect phenotypic adjustments that are maladaptive in adverse dietary environments. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

16.
This paper reports the weight‐length relationship (WLR) for thirty‐eight fish species from the Gulf of Castellammare (NW Sicily, Mediterranean Sea). A total of 59 870 fish were collected and measured during four seasonal trawl surveys carried out in 2005 at 10 to 200 m depth. The b parameter of the WLRs ranged from 1.79 (Cepola macrophthalma) to 3.56 (Conger conger). Significant differences in both a and b values among seasons were detected for eight species. Moreover, the condition factors (as weight‐at‐length) of Merluccius merluccius and Mullus barbatus were compared in different area/year combinations characterized by the presence or absence of trawling impact. While M. barbatus showed a higher condition factor in trawled areas/years, possibly due to density‐dependent factors linked to the increased biomass in the no‐trawl area, no such link was detected in M. merluccius.  相似文献   

17.
This study reports the length–weight relationship (LWR) and length‐length relationship (LLR) estimated for four fish species inhabiting in Chilika Lake, India. Total 504 specimens were sampled from mono‐filament gill nets (mesh size 12 mm, 22–24 mm, 34–38 mm, 42 mm) during January 2015 to December 2015. The estimated b values from LWR ranged between 2.79 (T. biaculeatus) to 3.29 (C. praeustus). In all species, the relationships between length‐weight and length‐length were highly correlated (p < .05). The study provides first world reports on LWRs and LLRs for all the 4 studied species.  相似文献   

18.
Length‐weight and length‐length relationships were estimated for four native fish species from the Yalong River and its tributaries, China. A total of 976 specimens were collected monthly using trap nets and electric fishing in May 2013 and July 2015 to February 2016. This study presents the first references on LWRs (length–weight relationships) and LLRs (length–length relationships) for three species (Gymnocypris firmispinatus, Paracobitis variegatus and Euchiloglanis kishinouyei). Moreover, maturation length, absolute fecundity and predominant food items for the four species were also described in the study.  相似文献   

19.
Length‐weight relations (LWR) of six fish species from Geum, Nakdong and Yeongsan rivers in South Korea was estimated. A total of 5,152 specimens were measured and weighed. The linear relationship of total length and total weight were highly correlated for all species. No previous information on LWRs on Rhinogobius brunneus species were found in Fishbase.  相似文献   

20.
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   

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