Length-weight relationships of the Indian Major Carp, Labeo rohita (Cypriniformes: Cyprinidae) from six drainages of Ganga basin, India

Abstract

ABSTRACT:The Indian Major Carp, Labeo rohita, is a geographically widespread and economically important food fish species in tropical freshwater of India and adjacent countries. We studied the lengthweight relationships of 1 033 specimens collected from the main channel of Ganga river and its five major drainages from March 2009 to July 2012. The length of males ranged from 16 to 92cm (females: 16 to 94cm). The growth is allometric positive (b>3) for males, females and pooled sexes. The coefficient of determination (r 2 ) in males ranged from 0,978 to 0,989 and for females from 0,958 to 0,985. Data from field populations are scarce and our results will be useful in the management and conservation of L. rohita populations in its natural range.Key words: LWR; Ganga basin; growth; wild; India. RESUMEN:La carpa mayor de la India, Labeo rohita es una especie de distribución amplia y de importancia económica en las aguas dulces tropicales de India y países cercanos. El presente estudio trata las relaciones talla-peso de 1 033 especímenes que fueron recolectados del canal principal del río Ganges y sus cinco principales drenajes, durante marzo 2009 y junio 2012. La longitud de los machos en diferentes ríos oscilaba entre 16 a 92cm y para las hembras entre 16 a 94cm. El crecimiento de esta especie fue alométrico positivo (b>3) para machos, hembras y sexos combinados. Además, la gama de coeficiente de determinación (r 2 ) en los hombres se registró desde 0,978 a 0,989 y para las mujeres que iba desde 0,958 a 0,985. Los datos generados en la presente investigación serán útiles para el biólogo pesquero y agencias de conservación en el manejo y conservación de las poblaciones silvestres de esta especie.Palabras clave: relación talla-peso; río Ganges; crecimiento; silvestre; India.The length-weight relationships (LWR) of fishes are important in fisheries biology because they allow the estimation of the average weight of the fish of a given length group by establishing a mathematical relation between the two (Mir, Mir, Patiyal & Kumar, 2014). Like any other morphometric characters, the LWR can be used as a character for the differentiation of taxonomic units and the relationship changes with the various developmental events in life such as metamorphosis, growth and onset of maturity (Thomas et al., 2003). Besides this, the LWR can also be used in setting yield equations for estimating the number of fish landed and comparing the population in space and time (Beverton & Holt, 1957). LWR parameters (a and b) are useful in fisheries science in many ways: to estimate weight of individual fish from its length, to calculate condition indices, to compare life history and morphology of populations belonging to different regions (Petrakis & Stergiou, 1995) and to study ontogenetic allometric changes (Teixeira de Mello et al., 2006). Furthermore the empirical relationship between the length and weight of the fish enhances the knowledge of the natural history of commercially important fish species, thus making the conservation possible.T...

Length-Weight Relationship and Condition Factor of Schizothorax plagiostomus found in River Jhelum from Kashmir Valley

“…Also it is well known that the functional regression b value represents the body form and is directly related to the weight affected by ecological factors habitat, area, seasonal effects, degree stomach fullness, gonad maturity, sex, health, preservation techniques and differences in the observed length ranges of the captured specimens 29,17,18 (Ricker, 1973. Several workers reported positive allometric growth in freshwater fish; notable among them are 20,34,23,9,19,45,30,42,35 in Cirrhina mrigala, Catla catla, Labeo bata, Labeo rohita, Pristolepis fasciata, Pangasius pangsius, Pseudorasbora parva and Macrognathus aculeatus respectively. The greater value of 'b' mainly depends on shape and fatness of individuals of fish.…”

Transcriptome analysis of the muscle of fast‐ and slow‐growing phoenix barb (Spinibarbus denticulatus denticulatus)

“…Wang et al reported that S. d. denticulatus formed the annual ring once in Xijiang River and matured in 4-5 years under culture conditions (Jiang & Yu, 2003;Wang et al, 2010). The growth rate of S. d. denticulatus is relatively lower than that of other carp species, including Labeo rohita, Cyprinus carpio, Ctenopharyngodon Idella, Spinibarbus sinensis and Spinibarbus yunnanensis (Iqbal Mir et al, 2013;Pokhrel, 2020;Yang & Chen, 1994;Zeng et al, 2017). Therefore, selecting individuals with high growth rate would be essential for breeding and conservation of S. d. denticulatus.…”