Search

Tenualosa ilisha is an anadromous fish from the Clupidae family that is distributed in several Asian countries. The relationship between T. ilisha from Indonesian waters and other waters in Asia is unknown, therefore this study was conducted to provide an overview of the relationship between T. ilisha from Indonesia and other waters in Asia based on the Cytochrome b gene (Cyt b) of mitochondrial DNA (mtDNA). The base sequence of T. ilisha from Labuhanbatu with a length of 568-572 base pairs (bp) was analyzed, then compared with Genbank data. All sequences compared showed that the composition of A+T (52.5%) was greater than G+C (47.5%). Genetic distance was calculated using Kimura two parameter (K2P); the lowest genetic distance of 0.000 was obtained between T. ilisha Labuhanbatu and Iraq with accession numbers LC619671.1; LC619673.1; LC619674.1. Meanwhile, the highest genetic distance is known to be 0.021 between T. ilisha Labuhanbatu and Bangladesh with the accession numbers MN748964.1, and MN748966.1. Neighbor-joining and maximum likelihood with 1000x repetition were the phylogenetic methods used to analyze the evolutionary relationships of T. ilisha. In general, both methods showed the same result that T. ilisha from Indonesia and other Asian waters are the same population. [ABSTRACT FROM AUTHOR]

Copyright of Social Anthropology / Anthropologie Sociale is the property of Berghahn Books and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The studied area is the single largest fishery in Bangladesh. The present work was conducted at two points of the Padma River (Sureshwar and Tarabunia) from July 2019 to June 2021 to monitor the efficiency of the 5th Hilsa sanctuary. Proportion of spent rate, length frequency, larvae and Jatka abundance, CPUE of larvae, the length-weight relationship of Jatka, plankton composition, and physico-chemical parameters of water were assessed and found adequate in the Hilsa sanctuary. [ABSTRACT FROM AUTHOR]

With priority given to various-sized samples of market-available Hilsa (Tenualosa ilisha), human health consequences of trace metals along with total essential acids, including the fatty acid (FA) and amino acid (AA) profile were measured and compared to different size groups (G I, G II, and G III) using chemometric approaches. Essential amino acids were lower than nonessential amino acids. The G III contained the highest (97.55%) saturated and unsaturated fatty acids. The highest concentrated metal was found in G1 among the groups and the order of metal (mg/kg) was Zn (205.01) > Mn (37.37) > Fe (69.39) > Cu (1.47) > Cr (1.31) > Ni (0.42) > Pb (0.017) > Cd (0.005). Even though the adult group showed no health hazards for Hilsa consumption, non-carcinogenic risks have been identified for G1 fish consumption by children. Continued monitoring is recommended to overcome the health consequences caused by fish consumption. [Display omitted] • The fat content of fish increases proportionally with their size. • Zn content displayed higher than the suggested concentration by FSG. • HI values for both adult and child groups followed a declining order: G I > G II > G III. • The health risk index displayed a higher risk for children consuming Hilsa fish than adults. • Most metals in the fish were of anthropogenic origin. [ABSTRACT FROM AUTHOR]

Sanctuaries are widely regarded as a protected area where fishing has been placed under some restrictions by local, state, regional and national authorities for the conservation and management of fisheries resources. These sanctuaries have a broad array of positive and negative social, economic, cultural and political impacts on fishers. This study aims to analyze the socio-economic and ecological benefits and costs of hilsa sanctuaries to protect single most important hilsa species using Sustainable Livelihood Approach (SLA). Under the Protection and Conservation of Fish Act of 1950, six sites along the Padma, Meghna, Tetulia, and Andharmanik rivers have been designated as hilsa sanctuaries. Findings of the current study revealed that most fishers perceived production of hilsa and other species were increased as a direct consequences of sanctuaries establishment. However, a considerable proportion of hilsa fishermen was found to have low socioeconomic capital, as measured by monthly income, housing circumstances and asset ownership. During the restricted fishing season in the sanctuaries, these households are particularly vulnerable to food insecurity. The government's compensation scheme is a good example of payment of ecosystem services in an open water fishery; however, this scheme does not include all the affected fishers. It is found that hilsa sanctuaries lead to income loss of the poor fishers which is insufficiently compensated by government support program. To compensate income loss, fishers resort illegal fishing which undermine the success of sanctuary. If the sanctuaries are to function effectively, affecting fishers must be addressed by offering enough compensation schemes so that fishers are able to support their families. Moreover, some fishers believed that a co-management approach involving fishers and government is the possible best management option for operating sanctuaries in a sustainable way. [ABSTRACT FROM AUTHOR]

Morphological characteristics, length-weight relationships (LWRs) and length-length relationships (LLRs) using multi-linear dimensions of Tenualosa ilisha (Hamilton, 1822) from the Ganges River, north-western Bangladesh, are examined. Samples (257 specimens) were occasionally collected during July 2018 – June 2019. Fin rays and scales were counted by a magnifying glass. A total of 9 morphometric lengths and total body weight (BW) were measured to the nearest 0.1 cm and 0.01 g for each specimen. Fin formula was: Dorsal, D. 15-19 (2-4/13-17); Pectoral, P. 14-16 (1/13-15); Pelvic, PV. 6-10 (1-2/5-8); Anal, A. 18-21 (1-2/16-20); and Caudal, C. 20-22 (2/18-20). Each LWRs were greatly significant (p< 0.001) with r² ≥0.963. Based on r² value, BW = 0.0215×SL3.01 was the fittest. Additionally, LLRs by TL vs. SL was the best fitted model among 8 equations depending on r² values. The provided biological information will support further studies and management of T. ilisha in the Ganges River and elsewhere using any liner-dimensions. [ABSTRACT FROM AUTHOR]

Hilsa species are broadly described as largely anadromous fish with a large valuable population size. It is well-known as one of the most critical commercial and occurs in marine, estuarine and riverine environments Hilsa shad, Tenualosa ilisha locally known as Sbour, migrates to the freshwater environment of the Shatt Al-Arab River systems for breeding. It was determined the genetic variation in 70 specimens of T. ilisha from four sites at the Shatt Al-Arab River, the mtDNA cytochrome-b gene was selected as a molecular marker for detecting genetic diversity, origin, and divergence of the population through comparing them with 6 samples from different locations at Indo-Pacific. The AMOVA analysis showed that the variation between groups is 60.97% and 39.02% within population indicating statistically significant P value (P

Hilsa species are broadly described as largely anadromous fish with a large valuable population size. It is well-known as one of the most critical commercial and occurs in marine, estuarine and riverine environments Hilsa shad, Tenualosa ilisha locally known as Sbour, migrates to the freshwater environment of the Shatt Al-Arab River systems for breeding. It was determined the genetic variation in 70 specimens of T. ilisha from four sites at the Shatt Al-Arab River, the mtDNA cytochrome-b gene was selected as a molecular marker for detecting genetic diversity, origin, and divergence of the population through comparing them with 6 samples from different locations at Indo- Pacific. The AMOVA analysis showed that the variation between groups is 60.97% and 39.02% within population indicating statistically significant P value (P<0.05). Furthermore, the maximum likelihood phylogenetic tree showed two main clusters of all T. ilisha groups representing two stocks of separated breeding grounds have a common ancestor. [ABSTRACT FROM AUTHOR]

Food and feeding habits of Tenualosa ilisha collected from two sampling locations in Brahmaputra River, Assam, India for a period of 12 months from May 2018 to April 2019 were studied. Index of preponderance revealed semi-digested animal matter (25.92 %) as the most dominant food item followed by Bacillariophyta (23.32 %). 31 genera of phytoplankton and 15 genera of Zooplankton were observed in the gut of the species. Major groups of Zooplankton include cladocerans, copepods, followed by rotifers, while diatoms, green algae and blue green algae were dominant phytoplankton groups. The anadromous tropical shad is planktivorous by nature and has a preference for Zooplankton in smaller size groups (< 250 mm) and phytoplankton in larger size groups (> 250 mm). GaSI values (mean±SE) ranged from 1.50±0.14 to 6.93±0.89 and HSI values from 0.58±0.06 to 1.54±0.15. Index of fullness was found to range from 7.08±0.42 to 1.81±0.40. Feeding intensity, GaSI, HSI values showed seasonal variation, found to be low during October to December and high during February to June. Size group-wise analysis of feeding intensity showed high feeding intensity in lower size groups (< 250 mm) and comparatively low feeding intensity and high percentage of empty stomachs in higher size groups (> 250 mm). RLG values ranged from 1.181±0.028 to 1.450±0.052. Monthly average RLG values were found to be highest during November and in the size group of 351 - 400 mm. Changes in food composition were noticed in both months and as well as size groups. [ABSTRACT FROM AUTHOR]

Hilsa, Tenualosa ilisha, Ham. 1822 , is the prime table fish and important commercial fish in the Indo-Pacific region. However, the species has recently declined drastically due to various factors. Our earlier studies recorded a significant association between the breeding season and its migration. Studies on milt and its biochemical properties are essential to ensure its successful conservation and artificial breeding. Here, milt samples of the hilsa of varied sizes were evaluated for their antioxidant property, fatty acid and amino acid content, and the histology of the testis. Analysis of milt antioxidants was done using free radicals DPPH, FRAPS & ABTS methods and compared with the free-radical quenching properties of the synthetic antioxidants. High performance liquid chromatography (HPLC) and gas chromatography and mass spectrometry (GC/MS) determined the composition of amino acids and fatty acids, respectively. The highest and lowest antioxidant activity was exhibited by hilsa milt samples M3 (b.wt 358.6 ± 0.75 g) i.e. 84.59 ± 0.48% and M12 (b.wt 168.35 ± 0.12 g) i.e. 27.53 ± 3.59%. Most notably, the antioxidant activity was found to follow a body weight gradient. Omega (ꙍ)-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (C22:6, DHA) and eicosapentaenoic acid (C20:5, EPA) were the predominant PUFAs and among the amino acids, arginine (0.70 g/100 g) was present in the highest quantity followed by glutamic acid (0.14 g/100 g) and proline (0.14 g/100 g). The histology study of the testis reveals the changes in the cells during the process of spermatogenesis. Histological images demonstrated the different stages of testis maturation of males sampled at the spawning sites. This baseline information generated is of its first kind in hilsa, a transboundary migratory fish in South Asian countries supporting conservation and artificial breeding for commercial production. • Semen of Tenualosa ilisha has significant antioxidant activity. • Antioxidants increase linearly with body weight. • Higher PUFA and specific amino acids indicate their importance in sperm performance. [ABSTRACT FROM AUTHOR]

The gut and flesh microbiome of the national fish of Bangladesh, Tenualosa ilisha , were analyzed using 16S rRNA gene sequencing. Our findings revealed a significant microbial disparity between sample categories and the habitat of hilsa fish, which will serve as a valuable foundation for further comprehensive studies on the hilsa microbiome., Competing Interests: The authors declare no conflict of interest.

Concentrations of Cd, Ni, and Pb were measured in the liver and muscle tissues of benthic omnivorous (Barbus grypus) and pelagic herbivorous (Tenualosa ilisha) fish collected from two sampling sites along the Karoon River, Khuzestan Province, southwest of Iran. Potential human health risks were evaluated by measuring the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR). The results highlight the important role of habitat and feeding habits in the uptake of HMs by the two species. The EDI for all HMs exceeded the oral reference doses (RfDo) provided by the USEPA, indicating the two fish species are not entirely safe for human consumption. The THQ values were within the permissible limit (< 1), while HI values (> 1) showed there was non-carcinogenic risk for consumers. The TR values for Pb were within the acceptable range (1.00E-06-1.00E-04) for both species. • HM levels were higher in benthic omnivorous than in pelagic herbivorous fish. • Habitat and feeding habits played a key role in accumulation of HMs. • EDI values exceeded the oral reference doses for all the HMs examined. • THQ values were within and HI exceeded the permissible limits. • TR values for Pb were within the acceptable range in both species. [ABSTRACT FROM AUTHOR]

Hilsa shad is one of the most important fisheries, contributing about 12.9% of the country's (Bangladesh) total fish production. There was no previous study on microplastic contamination of this important commercial fish. This study aims to identify, classify, and quantify microplastics (MPs) ingested by the national fish of Bangladesh, Hilsa shad, Tenualosa ilisha. A total of 287 MPs were recovered from the gastrointestinal tracts. All the fishes analyzed were contaminated with MPs. The mean (±SD) of the number of MPs was 19.13 ± 10.77 particles/fish, ranging from 7 to 51 particles/fish. Significant correlation was not found between the fish body length and MP abundance (rs = 0.287, p = 0.299), and between the fish body weight and MPs abundance (rs = 0.261, p = 0.347). The most dominant color was transparent (30%), followed by gray and black, contributing to 26% and 23%, respectively. The maximum number of MPs accounted for in the 300–1500 μm size class where fiber was the most dominant (50%) shape of observed MPs. These results provide a baseline of MP contamination in seafood from Bangladesh that should be useful for future monitoring efforts. The present study is the first research on MP contamination of Hilsa shad. • 100% of analyzed Hilsa shad had microplastics in their gastrointestinal tract. • A total of 287 MPs were obtained from all samples. • The dominant color of polymers was transparent (30%), gray (26%) and black (23%). • The maximum number of MPs were in the 300–1500 μm size class [ABSTRACT FROM AUTHOR]