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The Lancang-Mekong River watershed has extremely high fish biodiversity. With the rapid population growth and economic development in the river basin, fish diversity and fishery resources of this river are experiencing serious threats. Basic biological information on most fish species in the Lancang River, required to improve conservation in this area, is limited. This study aimed to provide new estimates of length-weight relationships (LWRs) by using the linear regression of W = aLb for eight indigenous fish species from the Lancang River, Southwest China. From 2018 to 2021, 534 specimens belonging to 3 families and 8 genera were collected using various types of fishing techniques. Standard length (SL) and body weight (BW) of each specimen were measured to the nearest 0.1 cm and 0.1 g, respectively. This study presents the first public records of LWR parameters of Schizothorax lissolabiatus, Poropuntius huangchuchieni, Tor sinensis, Scaphiodonichthys acanthopterus, Mystacoleucus lepturus, Hemiculterella macrolepis, Glyptothorax lampris, and Schistura porthos. The range of b values for the LWRs was 2.5378–3.1732, and the r2 values for all LWRs estimates ranged from 0.9102 to 0.9952. Intraspecific difference of b values across population and/or season was observed in S. lissolabiatus, T. sinensis, P. huangchuchieni, S. acanthopterus, and M. lepturus. The range of mean condition factor (K) and mean relative weight (Wr) was 0.97–2.39 and 100.29–108.18, respectively. This study updated information for FishBase and provided new record of maximum standard length for five species, namely, S. lissolabiatus, P. huangchuchieni, T. sinensis, S. acanthopterus, and M. lepturus. The findings of this study are essential for the management and conservation of locally indigenous fish and fisheries. [ABSTRACT FROM AUTHOR]

Morphometric characteristics, length-weight relationships (LWRs), and condition factors (K) were studied for five indigenous fish species belonging to five different families (Barilius barila Hamilton, Cirrhinus reba Hamilton, Chanda nama Hamilton, Mystus bleekeri Day, and Clupisoma garua Hamilton), from the River Ganga in Bihar, India. A total of 557 fish individuals were collected seasonally from September 2021 to August 2022 using a monofilament drift gill net and a conical trap net Khairel jal. In morphometric analysis, the highest degree of correlation was observed between the total length and the standard length for all species (except C. garua). The estimated exponent value b varies from 2.920 to 3.214, where the slopes of regression lines among the species have significant differences (p < 0.0001). The b value indicated that three species (B. barila, C. nama, and C. garua) follow positive allometric growth, whereas M. bleekeri shows isometric growth and C. reba exhibits negative allometric growth. The condition factor value for these fishes ranged from 0.67 to 0.98, which indicated that the population of C. reba was robust compared to all other species (p < 0.0001). A new maximum length (146.8 mm) was obtained for B. barila from India. The present study gives baseline biological information on five commercially important indigenous fish species found in the River Ganga, Bihar. As the population of these species has been dwindling in recent times, these data will be important for the conservation and sustainable utilization of these important species in the long run. [ABSTRACT FROM AUTHOR]

Aquaculture has great potential in the Terai region of Nepal due to the suitability of pond resources and government attempts to improve the fisheries sector. The majority of fish farmers in Chitwan belong to indigenous nationalities. Entrepreneurship skills help in uplifting local rural communities but due to the lack of attractiveness and economic production of fish in Chitwan, there is a higher chance of fish enterprise failure. Hence, an immediate need of assessing entrepreneurial behavior was felt and the study was carried out among indigenous fish farmers of Eastern Chitwan. For data collection, a questionnaire survey was conducted among eighty random respondents and a key informant interview was performed with expert farmers and fish scientists using the convergent parallel mixed method. Collected data were analyzed using SPSS version 22 and MS Excel. The entrepreneurial behavioral index (EBI) was calculated for each respondent, and it was assessed with various sociological and production factors. Average EBI was found among respondents. Most of the surveyed entrepreneurs have a low level of innovativeness, farming knowledge, and leadership while a medium level of motivation and decision-making ability. From the t-test, it was found that factors like AKC (Agriculture Knowledge Centre) visit, farming type, and organizational membership are significant but farmers' gender, extension consultation, training, information source, education, and experience are nonsignificant with respondents' entrepreneurship. Farmers who do commercial farming, visit AKC, and are members of social organizations have relatively more entrepreneurial behavioral indexes than other farmers. For the improvement of fish enterprises in the study area, training related to fisheries innovativeness, fish farming knowledge, and leadership is recommended through the collaboration of AKC and social organizations. [ABSTRACT FROM AUTHOR]

The present study describes new estimates of length‐weight relationships (LWRs) for 14 indigenous fish species collected from the Narmada River. Fish specimens were collected weekly using gill nets (30.0 m long, 3.0 m high, and mesh size 12.5–127.0 mm) between October 2021 and March 2022. Total length (TL) and weight for each specimen were measured to the nearest 0.1 cm and 0.1 gm, respectively. This study provides first species‐specific LWRs for four species (Tor tor, Rasbora daniconius, Rita gogra and Clarias magur), new maximum TL for seven species (Notopterus notopterus, Labeo bata, Systomus sarana, Crossocheilus latius, Xenentodon cancila, Channa marulius and Mastacembelus armatus), and new and wider size range for three species (Chitala chitala, Tenualosa toli and Labeo boggut). Findings of this study have implications in the management and conservation of the species‐specific fisheries resources within the geographical range. [ABSTRACT FROM AUTHOR]

Specimens of four fish species (Garra nujiangensis Chen, Zhao & Yang, 2009, Poropuntius opisthopterus (Wu, 1977), Creteuchiloglanis macropterus (Ng, 2004), and Glyptothorax lanceatus Ng, Jiang & Chen, 2012) were caught in the Nujiang River, China. Fish were sampled between May 2017 to July 2021 in irregular intervals, using gill nets (mesh sizes 6, 10, and 16 cm) and cage nets (mesh size 1 cm). Total length (to nearest 0.1 cm, L) and total weight (to nearest 0.001 g, W) were determined. Length‐weight relationships (LWRs) were estimated through the linear regression of W = aLb. The r2 values for all LWRs estimates were all above.96, indicating that no serious outlier values were included in the samples. [ABSTRACT FROM AUTHOR]

The present experiment was conducted to breed a vulnerable cyprinid fish, Dawkinsiarohani (Rohan's barb), in captivity through hormonal inducement using one of the reproductive synthetic hormones WOVA‐FH, since these fish did not breed spontaneously in captivity. The experiment was conducted in 500‐L capacity fibre‐reinforced plastic tanks with breeding hapa. The male (length 8.5 ± 1.5 cm and weight of 12 ± 2 g) and female (length 9.5 ± 2 cm and weight of 15 ± 1.5 g) brooders were injected intramuscularly with variable dose of WOVA‐FH and released into the breeding hapa at 2:1 (male:female) ratio. Varied doses of WOVA‐FH used for fish in the present study refer to 0.3 ml/kg (T1), 0.5 ml/kg (T2), 0.7 ml/kg (T3), 1.0 ml/kg (T4) and 0.0 ml/kg T0 (control). General courtship behaviour was observed in hormone‐induced fish after 6–9 h after injection. Breeding was observed in all the treatment group fish except T0 (control groups). Success of spawning, fertilization and hatching rate varied depending on the dose of hormone. Significantly higher fecundity (1142.3 ± 40.20 eggs/female), fertilization rate (90.2 ± 0.67%) and hatching rate (88.92 ± 0.25%) were achieved in fish injected with 0.7 ml/kg for female and 0.3 ml/kg for male per kg body weight compared to other hormone treatment groups. Dosage levels influence the percentage of spawning, egg stripping, fertilization and hatching rate. The present study successfully standardized the dose for induced breeding of D. rohani. The standardized breeding technology will be helpful in breeding, conservation and propagation of the endemic indigenous ornamental fish, D. rohani. [ABSTRACT FROM AUTHOR]

The present study estimated length–weight relationships (LWRs) for six indigenous fish species (Barilius gatensis, Salmostoma acinaces, S. boopis, Puntius amphibius, Hemibagrus punctatus and Ambassis miops) based on specimens collected from River Cauvery (including estuary) during July 2017–January 2020. The sampling surveys were carried out in three distinct sampling seasons, viz., the pre‐monsoon (March–May), the monsoon (July–October) and the post‐monsoon (November–February). Majority of the fish specimens dealt in the study were collected from multi‐meshed monofilament gill nets (mesh sizes 18, 30, 45, 60, 90, 110, 120 and 150 mm) operated by local fishers. For those sites situated in the protected areas, sampling was carried out by cast nets with prior permission from the local administration and the collected fishes were released back into river after length–weight measurements. The length measurements were noted as total length (TL) measured to the nearest 0.1 cm by using a digital Vernier caliper. A digital balance was used for weight measurements with an accuracy of 0.01 g. The study recorded a new maximum length of 48 cm for H. punctatus. The LWR data generated from the present study are significant for proper assessment of the stock status and their management, if collected together with other essential biological and physical parameters. [ABSTRACT FROM AUTHOR]

The present study aims at developing fish flour from two small indigenous fish species, that is, Puntius sophore and Amblypharyngodon mola. Fish flour developed from fresh fish species were analyzed for their nutritional compositions following standard protocols. Results indicated the protein, ash, calcium, phosphorus, potassium, magnesium, and iron content to be 55.15 ± 0.71 g/100 g, 18.14 ± 0.69 g/100 g, 1,850.34 ± 2.40 mg/100 g, 799.17 ± 1.50 mg/100 g, 653.26 ± 0.64 mg/100 g, 331.02 ± 2.11 mg/100 g, and 16.00 ± 1.29 mg/100 g, respectively, for fish flour developed from Puntius sophore and 61.32 ± 0.31 g/100 g, 15.43 ± 0.45 g/100 g, 2098.40 ± 2.37 mg/100 g, 1,012.81 ± 3.86 mg/100 g, 413.78 ± 1.47 mg/100 g, 256.82 ± 1.65 mg/100 g, and 12.53 ± 0.52 mg/100 g, respectively, for fish flour developed from Amblypharyngodon mola. The developed flours also had good functional properties with bulk density, water absorption capacity and fat absorption capacity of 0.52 ± 0.001 g/ml, 121.67 ± 2.89 ml/100 g, and 81.67 ± 2.89 ml/100 g, respectively, for Puntius sophore and 0.57 ± 0.01 g/ml, 119.67 ± 4.51 ml/100 g, and 65.00 ± 5.00 ml/100 g, respectively, for Amblypharyngodon mola. Practical applications: The edible fish flour developed from small indigenous fish species can serve as a good source of protein and minerals for children, adolescence, and individuals of other age groups. Due to its high protein content, it could be used commercially as protein supplement. It can also serve as a potential ingredient by various food processing industries for value addition of low protein snacks. In addition, it would also improve the utilization of small fish species thereby generating a source of livelihood for people living close to water bodies. [ABSTRACT FROM AUTHOR]

The one‐stripe spiny eel (Macrognathus aral, Bloch & Schneider, 1801) under the family Mastacembelidae, a native ornamental fish, were collected from the freshwater ponds and canals of West Bengal, with a purpose to raise the colony as ornamental fish broodstock. During acclimatization, fish were found to be lethargic and reluctant to consume feed followed by the appearance of deep wounds and red patches on the ventral part of the body surface. There was a mortality of 40.49% of affected fish within the next 48 hours. Post‐mortem examinations revealed the presence of metacercariae inside the body cavity and on internal organs, spreading up to the buccal cavity. The abundance of the parasite was 15 to 36 numbers per fish. The length of the metacercaria varied from 5.2 mm to 9.8 mm. The metacercariae were identified as Clinostomum complanatum by light microscopy. Further, molecular confirmation of identification was done using PCR amplification and sequencing of the 18S RNA gene. This is the first report of metacercarial infestation of Clinostomum complanatum with molecular confirmation in indigenous M. aral with high ornamental value. [ABSTRACT FROM AUTHOR]

This study provides new length‒weight (LWR) and length‒length relationships (LLR) for 25 indigenous fish species from Xingu River basin. Overall specimens were collected in different aquatic habitats in the Xingu River basin in quarterly collections between 2012 and 2018. The collections were carried out using distinct fishing gears, such as gill nets (20 to 180 mm mesh), seines (3 mm mesh), sieves (1 mm mesh), and casting nets (20 to 60 mm mesh). The present study shows the LWRs for 25 species, and the LLRs for 23 species. In addition, presents the new maximum total lengths for 20 species. [ABSTRACT FROM AUTHOR]

Summary: Length‐weight relationships (LWRs) were estimated for seven small indigenous cyprinid fish species including Securicula gora, Osteobrama cotio, Esomus lineatus, Pethia gelius, Megarasbora elonga, Gonialosa manmina and Glossogobius aureus occurring in the Kaptai Lake, Bangladesh. Fish were collected monthly basis between March and October, 2018 from fishermen catches landed in the fish landing center, Rangamati. Fishermen operated lift net (mesh size < 0.5 cm), punti net (mesh size < 0.5 cm) and cast net (mesh size < 0.5 cm) for capturing these species. The value of exponent b ranged between 2.769 and 3.212 and regression parameter r2 was between 0.926 and 0.992. New maximum total lengths were recorded for E. lineatus and G. manmina in this study. [ABSTRACT FROM AUTHOR]

The present study was undertaken with the objective to estimate the length‐weight Relationships (LWRs) for four species collected from the Brahmaputra River, Assam, India. The fish samples were collected quarterly from different sampling sites using gill net (mesh size ranges 1–1.5 cm, locally called Mola lungi jal), cast net (mesh size ranges 1.0–2.0 cm, locally called Kevalijal) and triangular dip nets (mesh size ranges 0.75–1.25 cm locally called khorajal) during the time period between May, 2016 to April, 2018 (2 years). The b value of the LWR ranged from 3.028 (for Parambasis lala) to 3.196 (for Psilorynchus balitora). In this study the relationship between length‐weight were highly correlated (p < 0.05). [ABSTRACT FROM AUTHOR]

Summary: Length‐weight relationships (LWRs) were estimated for three small indigenous fish species, (Sinogastromyzon szechuanensis, Sinogastromyzon sichangensis and Sinocrossocheilus labiatus) in the upper Yangtze River, China. Samples were collected using three types of local traditional fishing gears, including gill nets (mesh size: 1 cm), fish cages (mesh size: 0.5 cm), and electrofishing techniques (CWB‐2000 P, 12V, 250 Hz), in April, July and October 2013 and 2014, and April and October 2016. The sample size for each species were gathered separately, with 100 for S. szechuanensis, 381 for S. sichangensis and 49 for S. labiatus from National Nature Reserve for rare and endemic fishes of the upper Yangtze River, China. The length‐weight relationship parameter values of b were calculated as 2.986 for S. szechuanensis (b: 2.854–3.118), and 3.284 for S. sichangensis (b: 3.209–3.359) and 3.119 for S. labiatus (b: 2.911–3.326). The primary data will be meaningful for further research about sustainable development and scientific management of fishery resources of the upper Yangtze River. [ABSTRACT FROM AUTHOR]

The present study describes the length‐weight (LWR) and length‐length (LLR) relationships for three indigenous fish species from the Qingshui River, southwestern China. Fishes were collected by electrofishing in May 2015 in the middle Qingshui River. Total length (TL), standard length (SL) and fork length (FL) were measured to the nearest 0.1 cm with a digital calliper and weight (W) was determined with an electronic balance to an accuracy of 0.01 g. In addition, provides a new maximum total length for two species. [ABSTRACT FROM AUTHOR]

Length-weight relationships were determined for two small indigenous cyprinid fishes: Osteobrama cotio (Hamilton, 1822) and Salmophasia phulo (Hamilton, 1822) collected from Panchet reservoir, Damodar River, India. About 143 specimens of Osteobrama cotio (5.2-10.4 cm TL) and 113 specimens of Salmophasia phulo (2.9-8.2 cm TL) were collected from November 2014 to June 2016 using gillnets of mesh size ranging from 25 to 120 mm ( STR) and dragnets of mesh size 10-20 mm ( STR). No previous information on LWRs for these two species from an Indian reservoir was available in the literature. [ABSTRACT FROM AUTHOR]

Length-weight relationships ( LWRs) for three small indigenous fish species from the lower Brahmaputra in Assam, India: Glyptothorax telchitta, Nangra assamensis, and Gudusia chapra were studied on a monthly basis from February 2015 to January 2016. Various fishing gear types were employed: cast nets (9′ ½'), gillnets (30 × 0.9 m, 0.5″; 60 × 3 m, 1.5″) and mosquito nets (20 × 6 m, 0.04″). No previous reference is available on LWR data for two of these species. [ABSTRACT FROM AUTHOR]