Catfish Research Articles

EFFECT OF PROLONGED STORAGE IN ICE ON NUTRIENTS COMPOSITION AND SENSORY QUALITY OF FRESH POND RAISED CATFISH (Clarias gariepinus Burchell, 1822)

Fish storage on ice has been one of commonly used methods to preserve fresh fish for subsequent processing and consumption. This study was carried out to assess the effect of prolonged storage in ice on nutrient composition and sensory quality of whole fresh pond raised Catfish (Clarias gariepinus). Live fish samples, with an average weight of 500g were purchased from custom market in Maiduguri Borno state and transported in plastic bucket containing water to the Department of Fisheries, Research and Teaching Farm, University of Maiduguri were the experiment was carried out. The fish were degutted, washed and iced immediately. Data was analyzed using a statistical package SPSS version 20.0. The result of the study shows that that sensory quality of fresh C. gariepinus declines with time when stored in ice and that storage for not more than 15 days could maintain acceptable quality. The nutritional quality of cat fish deteriorated with time when stored in ice. Crude protein decreased from 30% at day1 to 21.57% at day9. Similarly, NFE decrease from 17.78 at day1 to 2.30% at day 15. However, Carcass fat increased with storage time, from 25.25 at day1 to 36.9% at day12. Dry matter content decreased with increasing time of storage indicating increased moisture content of the product. The result shows that that like any other fish C. gariepinus has a relatively longer shelf life when kept in ice. It is concluded that there is a significant change in the proximate composition of the fish...

Species tree analyses and speciation-based species delimitation support new species in the relict catfish family Diplomystidae and provide insights on recent glacial history in Patagonia

Diplomystidae is an early-diverged family of freshwater catfish endemic to southern South America. We have recently collected five juvenile specimens belonging to this family from the Bueno River Basin, a basin which the only previous record was a single juvenile specimen collected in 1996. This finding confirms the distribution of the family further South in northern Patagonia, but poses new questions about the origin of this population in an area with a strong glacial history. We used phylogenetic analyses to evaluate three different hypotheses that could explain the origin of this population in the basin. First, the population could have originated in Atlantic basins (East of the Andes) and dispersed to the Bueno Basin after the Last Glacial Maximum (LGM) via river reversals, as it has been proposed for other population of Diplomystes as well as for other freshwater species from Patagonia. Second, the population could have originated in the geographically close Valdivia Basin (West of the Andes) and dispersed south to its current location in the Bueno Basin. Third, regardless of its geographic origin (West or East of the Andes), the Bueno Basin population could have a longer history in the basin, surviving in situ through the LGM. In addition, we conducted species delimitation analyses using a recently developed method that uses a protracted model of speciation. Our goal was to test the species status of the Bueno Basin population along with another controversial population in Central Chile (Biobío Basin), which appeared highly divergent in previous studies with mtDNA. The phylogenetic analyses showed that the population from the Bueno Basin is more related to Atlantic than to Pacific lineages, although with a deep divergence that predated the LGM, supporting in situ survival rather than postglacial dispersal. In addition, these analyses also showed that the species D. nahuelbutaensis is polyphyletic, supporting the need for a taxonomic reevaluation. The species delimitation analyses supported two new species which are described using molecular diagnostic characters: Diplomystes arratiae sp. nov. from the Biobío, Carampangue, and Laraquete basins, maintaining D. nahuelbutaensis valid only for the Imperial Basin, and Diplomystes habitae sp. nov. from the Bueno Basin. This study greatly increases the number of species within both the family Diplomystidae and Patagonia, and contributes substantially to the knowledge of the evolution of southern South American freshwater biodiversity during its glacial history. Given the important contribution to the phylogenetic diversity of the family, we recommend a high conservation priority for both new species. Finally, this study highlights an exemplary scenario where species descriptions based only on DNA data are particularly valuable, bringing additional elements to the ongoing debate on DNA-based taxonomy.

Histology and histochemistry of the stomach of an Asian schilbeid, Clupisoma garua (Hamilton)

Abstract The cellular peculiarities and histochemical nature of the stomach in the freshwater catfish Clupisoma garua (Hamilton) were explored with light microscopic analysis. The pouch shaped muscular stomach was distinguished into the anterior cardiac and posterior pyloric regions. Histologically, the wall of stomach consisted of four distinct layers of the mucosa, submucosa, muscularis, and very thin serosa. The mucosa contained two kinds of epithelia: the superficial epithelium lined with columnar epithelial cells and the glandular epithelium crowded with numerous gastric glands that open through gastric pits. The vascularized submucosa was made up of loose connective tissues that extended into the mucosa forming lamina propria. The well-developed muscular layer was composed of an inner thick layer of circular muscle and an outer layer of longitudinal muscle bands. The detection and localization of mucopolysaccharides, glycogen, protein, and tryptophan in the various cells bounded in the stomach were described with the feeding behavior of the fish concerned.

Bioconversion of chicken feather wastes into value added bioactive peptide by Geobacillus thermodenitrificans PS41 strain

A need for an economically attractive method for feather waste utilization, lead us to research for a new effective technology assuring an outcome of valuable product. In this study, keratinase producing Geobacillus thermodenitrificans a bacterial isolate PS41 was used to convert feather waste into bioactive peptides. Feather peptide under 15 kDa had shown a maximum antioxidant activity and it was identified as radical oxygenase of Propionibacterium acne. The purified feather peptide from PS41 showed antibacterial activity, anticancer activity against human alveolar basal epithelial cells, and larvicidal activity against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus larvae in comparison to non-targeted organisms like zebra fish embryo and brine shrimp. The wound healing rate was significantly higher in peptide treated groups in comparison to standard and control groups respectively. Peptide treated wound had exhibited promisingly complete healing after 5 days of treatment in cat fish model and after 12 days of treatment in wistar albino rat. Histological analysis on experimental animal model showed that the tissue regenerating efficacy of peptide was more than the standard.

Comparative study of ovarian development in wild and captive-reared long-whiskered Sperata aor (Hamilton, 1822)

Long-whiskered catfish Sperata aor is a freshwater catfish known for its supreme flesh quality and fast growth, whose captive-reared broodstock denotes a difficult challenge for aquaculture. The reproductive dysfunctions in long-whiskered catfish raised in tank conditions were observed by comparing tissue biochemical composition and ovarian histology of wild female broodstock. Sixty (60) female broodstocks were used in the current study, consisting of 30 reared at sandy-muddy soil tank bottoms in captive conditions and 30 wild individuals collected from the haor basin during the breeding season. The fish reproductive state was investigated using the biometric and reproductive parameters, biochemical composition and levels of amino acids in the different tissues, and histological analysis of ovarian development. Results revealed that the biometrical parameters of wild and captive female broodstocks exhibited no remarkable difference (p > 0.05). Nevertheless, the wild fish had remarkably higher (p < 0.05) GSI (8.73%), oocyte weight (0.45 mg/egg), and ripeness (27.08%) in comparison with captive-reared broodstock. The total length and body weight, body weight and ovary weight, ovipositor diameter and ovary weight, and GSI and HSI displayed a positive relationship with R2 = 1, R2 = 1, R2 = 0.993, and R2 = 0.973, respectively, for wild broodstock, while R2 = 0.994, R2 = 0.806, R2 = 0.804, and R2 = 0.896, respectively, for captive broodstock. Additionally, the proximate composition in oocytes and liver tissues in both broodstocks did not differ significantly (p > 0.05). However, two essential amino acids (EAA), i.e., lysine and phenylalanine, and two non-essential amino acids, i.e., glutamic acid and glycine, were highly significant differences (p < 0.05) in the oocytes and liver of wild broodstock compared to the captive-reared broodstock. On the other hand, the EAA, e.g., isoleucine, threonine, leucine, and arginine, were highly dominated in both wild and captive female brood oocytes and liver. The ovarian histological slides from each fish group showed three oocytes developmental stages that indicated the asynchronous-reproductive ovarian oocytes of this fish. This study may be useful to fully understand the factors affecting the spawning and reproduction of S. aor broodstock, crucial for management in captive conditions as well as conservation and protection for sustainable aquaculture management of S. aor.

The DNA Barcode of cytb on Selais Bungkuk Fish (Hemisilurus heterorhynchus Bleeker) Originating from Riau, Indonesia

Selais bungkuk (Hemisilurus heterorhynchus Bleeker) is one of catfishes which is a member of family Siluridae and order Siluriformes. Selais bungkuk is an endemic fish in Riau Province. The scientific study of this fish is still limited including DNA barcoding study. This research aims to analyze the DNA barcode of cytochrome b (cytb) on selais bungkuk. Methods included colleting the fishes from Kampar River (three individuals) and Tapung River (three individuals); total DNA extraction from the muscle; electrophoresis, PCR, sequencing; and bioinformatics analysis. In this study, cytb DNA sequences were obtained from the six individual fishes studied with a size of 339 bp. The six sequences have been registered at GenBank with registration numbers MH633750, MH633751, MH633752 from Kampar River, MH633753, MH633754, and MH633755 from Tapung River. The BLASTn analysis showed that the selais bungkuk fish had the highest similarity of 92.63% with H. mekongensis and the lowest (90.00%) with selais janggut (Kryptopterus limpok). There were three nucleotides that characterize the selais bungkuk fish based on the cytb sequence such as nucleotide number 205, 229, and 280. The cytb sequence can distinguish groups of catfish separately based on their species. Conclusions and recommendations, the cytb sequences obtained in this study are the first to be reported in selais bungkuk fish and can be used as a reference for identifying this species.

Parasitological indicators, haemato-biochemical alternations, and environmental risks of heavy metals in cultivated and wild freshwater catfish, Egypt

Parasitological indicators, haemato-biochemical alternations, and environmental risks of heavy metals in cultivated and wild freshwater catfish, Egypt

Lead Nitrate Toxicity in the Suprabranchial Chamber and Air Sac of an Air Breathing Cat Fish Heteropneustes Fossilis(Bloch)

Abstract: Suprabranchial chamber and air sac is a vital accessory respiratory organ help the air breathing fish in ambient oxygen consumption which is one of the primary metabolic need for the survival of the the fish. Heteropneustes fossilis is an air breathing cat fish also capable to use atmospheric oxygen through their suprabranchial chamber and air sac which is known as its accessory respiratory organ. Lead nitrate, as a prominent heavy metal, when discharged directly in to water body as industrial waste, adversely effect in the capacity of oxygen consumtion of the fish by inducing toxic effect in the respiratory organs, gills, suprabranchial chamber and air sac of accessory respiratory organ. This study provide a background for evaluating the possible danger for human health resulting for consumption of the heavy metals toxicity affected fish. The toxic effect of Lead nitrate appear to be two types, one that occurs on a short term exposure to the toxicant evidenced by fish death and the other of chronic or long term effect detected by the constant changes in the normal biological system of the test fish.

ECONOMIC ANALYSIS OF CATFISH FARMING AND ITS CONTRIBUTIONS TO HOUSEHOLD POVERTY ALLEVIATION IN ANAMBRA STATE, SOUTH EAST NIGERIA

The study analyzed factors influencing the potency of catfish farming determined the cost and returns of catfish farming, estimated the poverty status among catfish farmers and ascertained the contribution of catfish farming to household poverty alleviation in the study area. Primary data used for the study was collected using well-structured questionnaire which was administered to sampled Catfish farmers in the study area. In analyzing the data, descriptive statistical tools (frequency counts, means and percentages), enterprise budgeting techniques, Tobit regression model, expenditure approach of determining poverty line, Foster, Greer and Thorbecke technique and z-test were used. The results indicated that factors such as pond size (0.0004), feed (0.6411), labour (-0.0003), and farming experience (0.0105) had influence on potency of catfish farming . Net returns analysis result reveals a return on investment of ?1.51 and it implies that the catfish production enterprise generated 1.51 times more income than expenses incurred for the production, a gross ratio of 66% and a Profitability Index (PI) of 0.34 which means that for every naira earned as revenue, 0.34kobo was returned to the farmer as net income. This result surely indicates that cat fish production is highly lucrative in the study area. At 0.05 probability level, the calculated z value was statistically significant and thereby ascertained the positive contribution of catfish farming to household poverty alleviation. Based on this study, the following recommendations are made: Since catfish production are profitable, government need to devote more resources to the catfish farmers to ensure that the best practices are adopted for further sustainability of the agribusiness, farmers should be trained on how to compound different types of fish feed to enable them reduce cost of feed. In addition Government should ensure increased credit facilities by the financial institutions to enable the farmers spread out their scale of operation

The bycatch of piramutaba, Brachyplatystoma vaillantii industrial fishing in a salinity and depth gradient in the Amazon estuary, Brazil

ABSTRACT The piramutaba, Brachyplatystoma vaillantii is a freshwater catfish that is the most abundant fishery resource in the Amazon estuary. Piramutaba trawling is done on industrial fishing scale and is characterized by the presence of many freshwater and marine bycatch species, with and without commercial value. Here we describe the bycatch of the industrial fishery of piramutaba in the Amazon estuary and evaluate the relationship of two important environmental factors, depth and salinity, with the accidental capture of freshwater and marine fishes in the Amazon estuary in the rainy and dry seasons. We identified 21 cartilaginous fish species (19.1% freshwater and 80.9% marine) and 125 bony fish species (25.6% freshwater and 74.4% marine). The bycatch included 64 species without commercial value (43% of all bycatch species), which are always discarded. Freshwater and estuarine fishes exhibited significantly higher abundances in shallower environments, while marine fishes were similarly abundant along the entire depth gradient. On the contrary, the abundance of freshwater fishes significantly decreased, and that of estuarine and marine fishes significantly increased with increasing salinity. Regarding the conservation status of the bycatch species, one is classified as vulnerable (VU), and seven as critically endangered (CR). The information on the bycatch of piramutaba fishery in the Amazon estuary is important to subsidize regional fisheries policies and the management of protected areas.

Extraction and characterizations of omega 3-fatty acid from cat fish collected from Arba Minch Chamo Lake

Fish oil is a nutrient-dense dietary product that contains long-chain omega-3 polyunsaturated fatty acid which is used to prevent and reduce type II diabetes, coronary heart disease, stroke, excessive blood pressure, and other cholesterol-related health issues. This study’s main goal is to use a solvent to extract omega-3 fatty acids from fish oil. The extraction of omega-3-fatty acid was carried out at a speed of 4000rpm, temperature 60 oC, pH 6.5, 70-minute extraction period and a ratio of Methanol: Chloroform (2:1 v/v %). The extracted samples were characterized by proximate value and the result was found to be moisture content of (0.933±0.023), Organic dry matter (53.11%), ash content (1.18±0.21) total protein (0.96),Insoluble matter(0.01), acid value (14.96±3.23), peroxide value (22.433±4.43),Refractive index(1.414), Saponification value (99.3±31.2), Fat% 43.7±8.45, iodine value (31.72±8.39), Density Value(0.975±0.099), % free fatty acid (0.846), pH (6.233±0.65), value specific gravity (1.31±0.095). The instrumental characterization was performed by using GC-MS, for the analysis of the FFA profiles and functional constitutions; we used UV-Visible and FTIR spectroscopy. To maintain compliance with commercial specifications and food standards, it is crucial to quantify proximate composition. With a ratio of 1.325 to 2.567, the high quantities of unsaturated fatty acids and low levels of saturated fatty acids imply that the oils and fatty acids have low cholesterol levels overall. Ratio for economic evaluation is necessary to ensure that by-products have a bright future and may be turned into new goods with a significant value addition.

Isolation of a Novel Mosquitocidal Bacterium &lt;i&gt;Bacillus cereus&lt;/i&gt; VCRC-641 from Fresh Water Fish &lt;i&gt;Clarias batrachus&lt;/i&gt;

In this study, search for new mosquitocidal bacterium was attempted from the gut content of the fresh water fish Clarias batrachus (walking cat fish) which resulted in the isolation of a highly potential mosquitocidal bacterium. The isolate was identified as Bacillus cereus VCRC 641 by Bacillus species specific molecular markers ilvD, pur and pycA gene sequence analysis. Laboratory mosquito larval toxicity assay (bioassay) against mosquito larvae revealed that this new isolate was highly potent against Culex quinquefasciatus followed by Aedes aegypti and Anopheles stephensi. The lethal concentration values at LC50 for these three mosquito species were 0.001, 0.004 and 0.007mg/ L respectively. Therefore, in the present study, this is the first report that a highly potential mosquitocidal bacteria of B. cereus VCRC 641 was isolated from the gut content of Clarias batrachus and suggested that it can be used for mosquito vector control program.

Follicular complex may predict reproductive tactics in siluriform fishes

In this study, we evaluated the morphology and morphometry of the layers that make up the follicular complex surrounding mature oocytes in the six fish species Auchenipterichthys longimanus, Ageneiosus ucayalensis, Hypophthalmus marginatus, Baryancistrus xanthellus, Panaqolus tankei and Peckoltia oligospila, belonging to the order Siluriformes, which inhabit the Amazon basin. On the basis of the morphology and thickness of the layers of the follicular complex, the species were divided into two groups: 1- A. longimanus, A. Ucayalensis and H. marginatus and 2 – B. xanthellus, P. tankei and P. oligospila. The total thickness of the layers that make up the follicular complex showed a difference between type III and IV oocytes for all species of each group. Differences in the theca layer, follicular cells and zona radiata between species and between groups were submitted to statistical analysis. Morphologically, group 1 showed columnar follicular cells and thin zona radiata. Meanwhile, group 2 displayed a layer of cuboidal-shaped follicular cells layer and thicker zona radiata. These differences may be related to the environment and reproductive behaviors, as group 1 migrates without parental care and has eggs that are generally smaller and abundant. While group 2, represented by loricariidae, inhabit lotic environments, have reproductive tactics of parental care and eggs that are generally large and in small numbers. Therefore, we can infer that the follicular complex in mature oocytes can predict the reproductive tactics of the species.

Records of malformed sea catfishes (Ariopsis seemanni and Ariopsis guatemalensis) (Actinopterygii: Siluriformes: Ariidae) off San Blas (Mexican Pacific)

Fish malformations can be an important hint for assessing the well-being of their populations and the quality of their habitats. Malformations have been observed in species of the order Siluriformes, including the family Ariidae. In this study, we report malformations in the blue sea catfish, Ariopsis guatemalensis (Günther, 1864), and the tete sea catfish, Ariopsis seemanni (Günther, 1864), collected in San Blas, Mexico. The malformations include missing eye, cleft lip, and malformed barbels. Such malformations could be blamed on substantial levels of pesticides in the environment, genetic factors, and/or a pathogenic effect of some parasites specific to the studied fish species.

Bioaccumulation and Risk Analysis of Selected Heavy Metals in Clarias Gariapinus and Tilapia Zili Fish Species of Abandoned Mining Ponds

Heavy metals (Cd, Co, Cr, Cu, Ni and Pb) were determined in some selected fish species (Clarias gariepenus and Tilapia zili) from Bokkos abandoned mining sites. Sample matrices examined were flesh gills, kidney and liver of each fish species. Twenty (20) sample sites were selected for the sample matrices under investigation. After sample collection and treatment, heavy metals were determined using Atomic Absorption Spectrophotometer (AAS, Bulk Scientific Model 210 VGP). The concentration patterns for each of the elements in the fish species showed significant and relatively similar patterns in cat fish with Ni having the highest concentration, followed by Cr, Co, Pb Cd and Cu in that order with respective. Cumulative bioconcentration in Tilapia zili showed that Cd &lt; Cu &lt; Pb &lt; Co &lt; Cr &lt; Ni respectively. Pearson correlation showed various interactions and relationships existing between and within sample matrices, indicating that these heavy metals have similar source, species or geochemical interaction. Only Co has a weakly positive correlation 0.58 with Pb while in Tilapia zilli, while Cu has correlation with Ni in Clarias gariepenus. Also the interactions and behaviors of the fish species suggests water and sediment for Cu, Ni and Co, Pb respectively. The relative contributions of Cr, Ni and Pb to the aggregated risk were 59.86%, 0.21%, 38.03% and 1.76% respectively. Consumption of these fish species from the study area therefore poses serious health concern upon consumption over time.

Identification and Characterization of Mosquitocidal Toxins From &lt;i&gt;Bacillus cereus&lt;/i&gt; VCRC-641

Bacillus cereus VCRC 641 was found to be an alternate larvicidal bacterial agent which was newly isolated from fresh water fish, Clarias batrachus (walking cat fish). The protein responsible for mosquito toxic effect was separated and purified by Sephacryl S-200 column chromatography and NATIVE PAGE. It was observed that a unique protein with molecular weight of 70kDa was the responsible factor for mosquito killing effect. Further analysis of the protein by liquid chromatography-mass spectrometry (LC-MS) it was identified as “Uncharacterized Protein”. The length of the uncharacterized protein was around 158bp. The uncharacterized protein was expected to have a molecular mass of 70 kDa, 51 amino acids, confidence score of 78.45 and mass of 206772.57. Therefore, in the present study we report for the first time that uncharacterized protein (70kDa) was the responsible factor for the mosquito killing effect.

The evolution of an ancient tapeworm lineage in its catfish hosts: vicariance, dispersal and diversification in Gangesiinae (Cestoda: Proteocephalidae)

Abstract The diversification of tapeworms of the subfamily Gangesiinae (Cestoda: Proteocephalidae), parasites of catfishes (order Siluriformes), is assessed using molecular and morphological evidence. A two-gene (lsrDNA and COI) phylogenetic analysis of all species of Gangesiinae (except Gangesia margolisi) resulted in a basal polytomy that included several lineages of Gangesiinae and Acanthotaeniinae. Palaeogeological events, along with host-shifting and dispersal, played prominent roles in the evolution of these tapeworms. Gangesia radiated through two major lineages in the Indomalayan and Palaearctic regions. Morphological changes during this radiation also included secondary loss of diagnostic morphological features of the genus, as in Gangesia mukutmanipurensis sp. nov., which lacks hooks and hooklets on its scolex. An updated key to the genera placed in Gangesiinae is provided and two new synonyms are proposed. A basal polytomy involving some of the potentially oldest lineages of Gangesiinae prevents firm conclusions regarding the ancestral area of origin of these tapeworms. Nevertheless, when the distribution and host-associations of Gangesiinae are considered in the context of the historical biogeography of their catfish hosts, the Indomalayan region appears to have been the ancestral homeland and a major centre of diversification of these tapeworms, with range expansions in western and northern parts of Eurasia and Africa.

Temporal expression of thyroid hormone regulating genes (tsh-b, tsh-r, dio2 and dio3) and their correlation with annual reproductive cycle of the Indian freshwater catfish, Heteropneustes fossilis (Bloch).

Photoperiod and temperature are well-established environmental cues for gonadal growth in seasonally reproducing organisms. The photoperiod is known to regulate seasonal reproduction via induction of thyroid hormone regulating genes in the saccus vasculosus (SV) of fishes. However, SV is absent in many seasonally breeding fishes, including Heteropneustes fossilis. H. fossilis is a long-day breeding catfish in which gonadal recrudescence begins six months earlier than spawning. The present study attempted to analyse the expression of thyroid hormone-regulating genes (tsh-b, tsh-r, dio2 and dio3) in the brain, liver and ovary. In the brain, upregulated expression of thyrotropin-beta subunit (tsh-b), deiodinase2 (dio2) and deiodinase3 (dio3) genes is concomitant with the increasing photoperiod and temperature in nature, which may appear to regulate seasonal reproduction. Both deiodinases, dio2 and dio3, were also upregulated in the liver and ovarian tissue during the gonadal growth phase. The upregulation of deiodinases may enhance the metabolism and activity of tissues, thereby facilitating their respective roles. The expression of these genes was also assessed in the brain, liver, ovary, kidney, skin, spleen and gill tissues during the spawning period. The ubiquitous expression of deiodinases may point to enhanced activity in their organ-specific role. The present study speculates that expression of tsh-b, tsh-r, dio2 and dio3 genes during the reproductive phase of H. fossilis might be involved in the regulation of seasonal reproduction.

Seasonal Variation of Fish Diversity in Narmada River at Dindori District, Madhya Pradesh, India

The present study deals freshwater fish diversity of Narmada River in Dindori District during period October 2021 to September 2022 in pre monsoon, monsoon and post monsoon season.Narmada River is a life line of Madhya Pradesh. The fish diversity is correlated with biological and PhysioChemical parameters that affect the productivity of water body. Majority of fishes are exploited for human consumption. The present study strives have made to collect, classify and identify fish of river Narmada in Dindori District. The study operated on a stretch of the river approximately 30 km from October 2021 to September 2022.The survey indicated that 37 species of fish were found in this area of the river. The major fish abundance was noticed viz Major carps, Minor carps and Cat fishes. The several species of fish belonging to order Cypriniformes, Siluriformes, Beloniformes, Anabantiformes, Perciformes, Synbranchiformes and Gobiformes in which maximum 20 species belonging to the order Cypriniformes.Fish diversity was decline on the basis of seasonal changes. The present study has been conducted to assess the fish diversity in Narmada River in Madhya Pradesh.

Age and growth assessment of the near-threatened fish Rita rita (Siluriformes: Bagridae) in the Ganges basin

Introduction: Rita rita is a freshwater catfish under threat of extinction, mainly from loss of breeding and nursing grounds. A reliable method for age and growth estimation is needed by fishery managers. Objective: To identify the best body structure for age and growth estimation. Methods: We assessed estimates precision based on Average Percent Error (APE), Coefficient Variation (CV), and Percent Agreement (PA) between readers separately analyzed each calcified structure. We used 390 fish samples from three rivers, Ganga, Yamuna and Ramganga, from September 2018 to August 2019. Results: The three indicators favored the use of vertebrae for age estimation; the growth band seems to be annual and formed from May to September. The growth equations were Lt = 90.19(1-e-0.145(t+0.51)) for Ganga; Lt = 91.19 (1-e-0.14(t+0.59)) for Yamuna and Lt = 89.63 (1-e-0.15(t+0.68)) for Ramganga. Conclusion: This species reaches moderate growth in these rivers, where vertebrae are the recommended age estimation structure, followed, in case of need, by sectioned otoliths, whole otoliths and opercular bones. Pectoral spines should be avoided, especially in older fish.