Total Length Weight Relationship Research Articles

Status ofPseudorasbora parvain the Tiber River Basin (Umbria, central Italy) 20 years after its introduction

The aim of this research was to assess the distribution, abundance and growth of the non-native topmouth gudgeon Pseudorasbora parva that was recorded for the first time in the Tiber River Basin (central Italy) in 1994. The competitive interaction of P. parva with four native fish species was also investigated. The study area comprised 92 watercourses of the Umbrian section of the Tiber River Basin. Demographic and environmental data were collected during the period 1990−2014 in 171 sampling sites. The results of this study showed a wide distribution of P. parva in the study area, with records from 23.39% of all sampling sites (40 out of 171). This species inhabits the downstream reaches, where the presence of many non-native species and the poor environmental quality are associated with a decrease in native fish species. A total of 5570 specimens of P. parva were collected and five age classes (0+ to 4+ ) were identified. The equation for the total length-weight relationship of P. parva was W = 0.021T L 2.673±0.015 . For the chub Squalius squalus , the Tiber barbel, Barbus tyberinus, and the roach, Rutilus rubilio, the average values of the relative weight were significantly higher in the sites where P. parva was absent. The results of the present study suggest the need to undertake proper strategies for native biodiversity conservation.

Composición, crecimiento e índice de condición de una población de<i> Poecilia reticulata</i> (Pisces: Poeciliidae), en un estanque en Heredia, Costa Rica

A pond population of Poecilia reticulata was studied in Santo Domingo, Heredia, Costa Rica, between September and November of 1998. The sex ratio was 1:0.49 (males:females). The mean total length was 34.43 +/- 7.26 mm for females, 23.50 +/- 2.24 mm for males and 12.27 +/- 3.41 mm for juveniles. The mean total weight was 0.69 +/- 0.48 g for females: and 0.16 +/- 0.05 g for males and 0.026 +/- 0.027 g for juveniles. The total length-weight relationship for the total population was P= 6 x 10(-5) Lt 3.3272 (r2 = 0.9613). The condition index equation was K = 25.755 e(0.004Lt) (r2 = 0.8925) for females and K = 26.767 e(0.003Lt) (r2 = 0.907) for males. The mean condition index was 31.29 +/- 0.55% for females and 28.52 +/- 0.19% for males. Both sexes reached the sexual maturity when the males and females overcame the 20.00 mm and 23.5 mm of Lt respectively.

Morphometric characters of Nile tilapia (Oreochromis niloticus) in Thailand

The present study is conducted to describe the morphometric characteristics of a Thailand strain of Oreochromis niloticus . The total length of the observed fish ranged from 7.96 - 17.36 cm. Body measurement and proportions are extensively used for identification of this species. The following 18 measurements are determined for each fish: Total length (TL); Standard length (SL); Body depth (BD); Pre-dorsal length (PDL); Pre-pectoral length (PPCL); Pre-pelvic length (PPVL); Pre-anal length (PAL); Depth of caudal peduncle (DCP); Length of caudal peduncle (LCP); Head length (HL); Eye diameter (ED); Snout length (SNL); Upper jaw length (UJL); Lower jaw length (LJL); Caudal fin length (CFL); Pectoral fin length (PFL); Length of dorsal fin base (LDFB); Length of anal fin base (LAFB). The rate of growth of different morphological body parts of the fish in relation to its total length is studied. Additionally, the total length and body weight relationship is found to be a straight line in logarithmic scale expressed as Log BW = 3.026 Log TL - 1.839. The value of regression co-efficient obtained for the length-weight relationship is 3.026. This finding suggests that selection for growth using this equation is a good alternative for measuring weight in the field, when accurate weighing balances are not available. Hence, the present study provides the information of the various body parts measurements of Tilapia and establishes mathematical equations relating to these various morphometric relationships which can be utilized for the conversion of one measurement into another. doi: 10.14456/WJST.2014.76

Comparison of some biological aspects between the two sexes of the European hake Merluccius merluccius from the Egyptian Mediterranean waters

Research on morphometrics, size frequency, length–weight relationship and condition factor belonging to both sexes of Merluccius merluccius in the Egyptian Mediterranean waters off Alexandria in the period from 2009 to 2011. The differences between the mean values of the measured morphometric characteristic in the females and males were statistically significant in eight of the fifteen morphometric measurements. The total length–gutted weight relationship was determined for males (Loga=−2.5016, b=3.22296), females (Loga=−2.5886, b=3.2816) and combined sexes (Loga=−2.5069, b=3.22738). Total length–weight relationship was for males (Loga=−2.4715, b=3.2230), females (Loga=−2.6279, b=3.3182) and combined sexes (Loga=−2.46607, b=3.21954). Condition factor was calculated by gutted weight. Females have higher condition value (0.670) than males (0.640). The highest value of condition factor was recorded in winter.

Biología reproductiva de <i>Lutjanus guttatus</i> (Perciformes: Lutjanidae) en el Parque Nacional Natural Utría, Pacífico colombian

Las áreas protegidas son importantes para la conservación de las poblaciones naturales ya que funcionan como zonas de refugio, alimentación y reproducción en la que los organismos deberían estar eximidos de la presión antrópica, pero en aquellas áreas donde se permite la pesca, es elemental conocer los aspectos reproductivos de las especies que soportan la presión pesquera, ya que ésta información relacionada con las abundancias, tallas y frecuencias de captura pueden ofrecer mejores criterios para tomar decisiones de manejo y conservación de los recursos pequeros. La biología reproductiva del pargo lunarejo Lutjanus guttatus se estudió entre abril 2008 y febrero 2009 en el Parque Nacional Utría, Pacífico colombiano. Se analizaron los volúmenes de captura, estructura por tallas, proporción de sexos, fecundidad, talla media de madurez, áreas y épocas de reproducción (n=278). La longitud total osciló entre 18 y 56cm con una media y desviación estándar de 29±6.4cm. La talla media de madurez fue estimada en 23.5cm de longitud total, la fecundidad absoluta fue 156 253.11 ovocitos, con una moda de 4μm de diámetro y un desarrollo gonadal asincrónico. La presencia de individuos maduros y de un alto factor de condición sugieren épocas de desove en junio, septiembre y octubre en litorales rocosos y arenosos.

Relación longitud-peso del Perico (Trachelyopterus badeli Dahl, 1955) en el embalse de Urrá, Colombia

The length-weight relationship of Perico ( Trachelyopterus badeli Dahl, 1955) in the Urra s dam, Upper Sinu River, Colombia, between January and December 2003 was estimate. The length-weight relationship TW=aL b and condition factor Cf=TW/L b were estimated. Total length-weight relationship estimated was TW=0.005 (±0.11) TL 3.31 (± 0.09) , r=0.95, n=608, and its growth coefficient was statistically different from 3. Standard length-weight relationship estimated was TW =0.015 (±0.12) SL 3.09 (± 0.10) , r = 0.93, n = 608, and its growth coefficient was statistically similar to 3. Statistically significant differences between monthly growth coefficients were found and correlation between the condition factor and the hydrological cycle of Urra s dam in the study year was observed.

Morphological variability of the 11th generation strain of nile tilapia, (Oreochromis niloticus) and traditional genetically improved farmed tilapia

To investigate the morphological variations 12 morphometric and 11meristic characters were studied for 100 individuals of the same age of traditional strain GIFT (5th generation) and recently developed 11th generation strain (GIFU) of Nile tilapia, Oreochromis niloticus. No significant difference was found between total length and other body measurements at 5% level. However, GIFU showed faster linear growth on body depth, maximum body circumference and minimum body circumference where GIFT showed faster linear growth on standard length and head length. On meristic characters, notable variations were observed in case of scale above and below the lateral line, where GIFU individuals showed greater number of scales in both cases. The total length and body weight relationship of both the strains were found to be straight line in logarithmic scales. The mean values of condition factor (K) have been found to be 1.671 for GIFT and 1.711 for GIFU and the mean values of relative condition facto (Kn) were 1.001 and 1.002 for GIFT and GIFU respectively. Findings of the present study suggested the variability of strain GIFU and GIFT in some important parameters. DOI: http://dx.doi.org/10.3329/jbau.v9i2.11050 J. Bangladesh Agril. Univ. 9(2): 345–349, 2011

Morphology, growth and reproduction of the non-indigenous topmouth gudgeon Pseudorasbora parva (Temminck et Schlegel, 1846) in the wetland of Alma-Gol, Northern Iran

Observation of topmouth gudgeon was actually the first record of its being in this wetland, indicating increasing of its distribution in new habitats. So, morphological characters, growth and reproduction of this species as newly introduced non-indigenous fish into Iran were studied in the Alma-Gol wetland (northern Iran) during a period from September 2000 to August 2002. Inter-sexual comparison of morphological characters revealed that there are significant differences in total length, head width, A-C distance and dorsal fin rays between sexes. The maximum age of the fish studied was 3+ years and 4+ for females and males respectively. Observed lengths-at-age were different between sexes, with males longer and heavier than females in all age groups. The slope of the total length-weight relationships differed significantly between sexes, being negative allometric for both sexes. The overall ratio of males to females was 1.625: 1. The highest average values of GSI were 11.93 and 6.98 for females and males respectively in spring samplings. Absolute fecundity estimates ranged from 965 to 2930, with a mean value of 2214.34 ± 445.24(SD) eggs.

Dimorfismo sexual y relaciones morfométricas de Atlantoraja platana (Günther, 1880) en aguas del golfo San Matías, Patagonia

Sexual dimorphism and morphometric relationships of Atlantoraja platana (Günther, 1880) in San Matías gulf waters, Patagonia.The skate Atlantoraja platana, commonly known in Argentina as “raya platana”, is endemic to the Southwest Atlantic. It is distributed from Brasil (24°S) to north Patagonian waters (42°11’S). In this study the morphometric aspects of this skate were described. In the San Matías gulf (41°-42°S y 64°-65°W), a total of 778 females and 709 males were sampled from different sources between 2004 and 2006. The total length ranged was 19 to 89 cm for females and 19 to 79 cm for males. Atlantoraja platana was sexually dimorphic in total length-weight and total length-disc width relationships. Since 41 cm onwards the females are being heavier than males. The total length-weight relationship was Pt= 0.0132 x Lt2.91 for females and Pt= 0.0222 x Lt2.77 for males. The total length-disc width relationship was DW= 7.27 + 0.762Lt for females and DW= 7.768 + 0.798Lt for males. This is the first report of morphometric relationships of this species in the Argentinean Sea and they should be used for comparison purpose between different latitudinal localizations of this skate.

Total length-weight relationships among Thai freshwater fishes and the influence of capture location and preservation

Total length-weight regressions on logarithmic transformed data are provided for 33 species, with 26 apparently being first estimates. All regressions are highly significant with slope values between 2.5720 and 3.4436. Slopes and intercepts of length-weight regressions did not differ significantly with location for each of three species. Preservation in 10% formalin for 10 days followed by 30 days in 70% ethanol did not significantly influence regression slopes for the three species, length ranges and/or locations examined (ancova). Significance among regression intercepts was equivocal with ancova analyses mostly suggestive of differences and overlap of 95% confidence limits mostly suggestive of similarities.

Age, growth, reproduction and feed of longnosed skate, Dipturus oxyrinchus (Linnaeus, 1758) in Saros Bay, the north Aegean Sea

Summary The age, growth, reproduction, and feeding of longnosed skate (Dipturus oxyrinchus) were studied using 179 specimens from the Saros Bay (North Aegean Sea) between March 2005 and December 2007. Composition was 49.7% females and 50.3% males. Total length of females ranged from 14.9 to 100 cm (disc width, 9.8–65 cm), and of males from 15.2 to 86.5 cm (disc width, 10–57.5 cm). Total length-weight and disc width-weight relationships are described by the equations W = 0.0008*TL3.35 and W = 0.0043*DW3.29, respectively. The age data, derived from vertebrae readings, were used to estimate the growth parameters of the von Bertalanffy equation: L∞ = 256.46 cm, K = 0.04 year−1, t0 = −1.17year. The maximum age was 9 years. Males matured at 64–65 cm (disc width, 43.5 cm) and females at 82–83 cm TL (disc width, 53 cm). The stomach contained mainly Parapenaus longirostris, IRI: 93.47%.

The Biology Of The West African Clariid, Clarias macromystax Gunther, 1864 (Osteichthyes: Clariidae) In A Nigerian River Basin

The biology of the West African clariid, Clarias macromystax, was studied in Anambra river basin, Nigeria. The clariid occurred more abundantly and frequently in forest floodplain ponds than in other habitats, and was totally absent in the river systems. Length ranged from 9.7 to 30.2 cm TL and weight from 9 to 168 g; females were heavier, but not longer, than males. The b-values (2.4190-2.5209) of the total length-weight relationships exhibited negative allometric function. Mean relative condition, Kn, was better in females than males but showed a definite cycle in both sexes. Over 50% of both sexes were mature at 15.1-20.0 cm TL in their first year of life. Fecundity ranged from 2.136 x 103 to 37.250 x 103 (mean 14.942 x 103± 11.248 x 103) and correlated highly and positively with length, body weight and ovary weight. Ovary weight was the best predictor of fecundity. Communal spawning involving C. macromystax and C. agboyiensis occurred. Feeding was carried out throughout the day with higher feeding intensity at night. Food of primary importance were Caridina niloticus, Sudanonautes africanus, Odonata naiad, terrestrial Orthoptera, formicoid Hymenoptera, Dytiscidae, Oreochromis niloticus, Parachanna obscura, fruits and seeds, plant detritus and mud. Diet breadth was season-dependent. The clariid fed by foraging, shoveling and surfacefeeding. E. clarias, Procamallanus laevichonchus and a larval spiruroid parasitized various organs. C. macromystax is a new host record for these helminth parasites. Keywords: Clarias macromystax, Abundance, Reproduction, Food, Parasites, Anambra river basin, Nigeria. Animal Research International Vol. 1 (3) 2004 pp. 190-199

Age, growth, reproductive biology and feed of the common guitarfish ( Rhinobatos rhinobatos Linnaeus, 1758) in İskenderun Bay, the eastern Mediterranean Sea

The age, growth, reproduction, and feeding of common guitarfish ( Rhinobatos rhinobatos) were studied using 225 specimens from the İskenderun Bay, (eastern Mediterranean). Females made up 43% and males 57% of the individuals. The total length of females ranged from 22.2 to 81 cm, and of males from 22 to 120 cm. The total length–weight relationships was W = 0.0036 × TL 2.93. The age data, derived from vertabrae readings, were used to estimate the growth parameters of the von Bertalanffy equation: L ∞ = 128.6 cm, K = 0.29, t 0 = −0.89. The maximum age was 5 years. The parturition time of common guitarfish occurred in summer (from May to September). The mean TL and mean weight of developed fetuse were 25.7 cm TL and 48.5 g, respectively. Males matured at 68 cm TL and females at 69 cm TL. The stomachs contained mainly Crustacea.

Biología reproductiva del gatuzo Mustelus schmitti Springer, 1939 (Chondrichthyes, Triakidae) en el área de Puerto Quequén, Provincia de Buenos Aires

Reproductive biology of Mustelus schmitti, Springer, 1939 in Puerto Quequén, Buenos Aires Province. The reproductive biology of M. schmitti collected from the commercial bottom trawl fishery operating in Puerto Quequén, Argentina is investigated in the present study. The specimens were sampled seasonally during 2003–2004. The number of sharks collected was 637 (298 males and 339 females), including 190 pregnant females with 1,103 embryos. Size ranges for males were 419 – 819 mm total length (LT) and 417 – 951 mm LT for females. Total length and body weight relationship was different between sexes (P<0.05). In contrast, embryos did not show differences between sexes (P>0.05). Size frequency shows that females attain larger length and weight than males. Fifty percent (50%) of maturity size shows that males mature at a lower LT (567 mm) than females (598 mm). The left testis reached larger weight and length than the right one (P<0.01). Average values of the IG and IH per season varied significantly for males and females (P<0.05). Average values of the white and yellow ova per season showed significant differences (P<0.05) . The maximum diameter of the left oviducal gland was greater than the right one ( P<0.05) and both exhibit seasonal changes (P<0.05). At greater LT the females had more mbryos per brood (P<0.01) than bigger puppies (P>0.05).

Biological Characteristics of the Blue Sucker in the James River and the Big Sioux River, South Dakota

ABSTRACT Little is known about the relative abundance and biology of the blue sucker (Cycleptus elongatus), a species that may be declining in some parts of its range. We described the age, growth, condition, length distribution, and habitat preference of the blue sucker in two South Dakota rivers. Specimens were collected from the James River (n=74) and Big Sioux River (n=28) during the summer of 2000. Although five macrohabitats were sampled with electrofishing and hoopnets, most individuals were collected from riffle habitats and downstream of rock dams. Total length-weight relationships were log10 W= −6.14+3.37 (log10L) (r2 = 0.92) for blue suckers from the James River and log10 W= −6.52+3.50(log10L) (r2 = 0.97) for fish from the Big Sioux River. Mean condition factors (K = W(105)/L3) of blue suckers were 0.79 (SE = 0.07) for the James River and 0.73 (SE = 0.07) for the Big Sioux River. Blue suckers between 500 and 700 mm dominated length distributions (range = 374–717 mm) of both samples. Ages ranged from two to nine years, but six-year-old fish were captured most frequently. Blue suckers grew rapidly during juvenile stages (< age 5); however, growth slowed afterward.

Specific method of fishing for Sparidae species in the eastern Adriatic

“Tramata” fishing or fishing using vibrating ropes is a very old method and it is unique to the eastern Adriatic. It is the main commercial method of fishing of seabream (Sparidae) species. This paper describes the gear, methods and exploitation characteristics of tramata fishing, based on the research conducted from 1986 to 1999. Also, some parameters (length range, mean length, modal length and the parameters of the total length–weight relationship, length at first maturity, spawning period) are given for the dominant seabream species in catches from tramata fishing. Evaluation of its harmful effect on fish in coastal areas has been made according to the percentage of immature specimens in the catches.

Growth of marbled spinefoot Siganus rivulatus Forsskål, 1775 (Teleostei: Siganidae) introduced to Antalya Bay, eastern Mediterranean Sea (Turkey)

The age and growth of the marbled spinefoot, Siganus rivulatus Forsskål, 1775, were determined based on specimens collected from Antalya Bay (eastern Mediterranean), during the period from October 1996 to August 1998. Total length–weight relationship was estimated as W=0.0064 L 3.221 for females, W=0.0079 L 3.135 for males. Growth parameters of the von Bertalanffy equation were computed for females and males as: L ∞=22.55 cm, W ∞=146.8 g, k=0.267 yr −1, t 0=−0.47 and L ∞=21.06 cm, W ∞=112.1 g, k=0.343 yr −1, t 0=−0.54 , respectively. Age was determined by posterior body scale readings. Maximum observed age was 8 years, suggesting that the species is long-lived.

Total Length-Weight Relationships and Condition Factors for the Arctic Grayling, Thymallus arcticus (Pallas), in Alaska

Total Length-Weight Relationships and Condition Factors for the Arctic Grayling, Thymallus arcticus (Pallas), in Alaska

Population dynamics and the management of the Indo-Pacific king mackerel &lt;i&gt;Scomberomorus guttatus&lt;/i&gt; from the upper Bay of Bengal off Bangladesh coast

Growth and mortality parameters, exploitation rates, annual recruitment patterns and length-weight relationships were estimated using FiSAT program from monthly length-frequency and weight samples of Indo-Pacific king mackerel, Scomberomorus guttatus, captured mainly by drift gill nets from the upper Bay of Bengal off Bangladesh coast. The aim was to estimate growth parameters, mortality rates, exploitation rate and recruitment pattern of S. guttatus for sustainable management. The von Bertalanffy growth parameters asymptotic length L∞ (cm) and growth constant K (per year) were 73.5 and 0.6, respectively. The L∞ and Z/K estimates provided by Wetherall plot were 73.3 and 2.3 cm. The annual rate of fishing mortality (F = 0.806) was low compared to the relatively high natural mortality (M = 0.994). The exploitation rate (E = 0.45) shows that the species was not over-exploited in the region. About 77.1% of S. guttatus were recruited during May-July and 23.0% during September-October. The growth performance index (φ′) was 3.5. The total length and body weight relationship was W = 0.0101 L 2.8622 suggesting that the growth rate was negative allometric (b&lt;3). The growth parameters derived in the current study are comparable with previous estimates available for the same species. DOI: 10.3329/bvet.v27i2.7558 Bangl. vet. 2010. Vol. 27, No. 2, 82-90