3 research outputs found
Preserving cultural heritage: Community fishing among the Rabha community in Assam
The case study depicts the community fishing practices followed by the Rabha community of Assam
Cracking the code of hatchery-based mass production of mola (Amblypharyngodon mola) seed for nutritionsensitive aquaculture
Introduction: Small indigenous fish species (SIS) can be particularly rich in micronutrients and make a crucial contribution toward improving human nutrition. The introduction of mola (Amblypharyngodon mola), an SIS, which is particularly rich in vitamin A, into smallholder carp aquaculture systems has been widely promoted over the past decade as a promising nutrition-sensitive innovation. However, standardized techniques for the hatchery mass production of mola do not yet exist. We hypothesized that the lack of commercial hatchery mass-production techniques for mola seed is the key barrier limiting potential for widespread adoption of carp–SIS polyculture.
Methods: To address this gap, we conducted breeding trials at a private hatchery in Odisha, India, from July to September 2022, to identify standardized methods for the hatchery-based mass production of mola seed. Breeding was induced using a synthetic gonadotropin-releasing hormone analog (SGnRHa) at 0.5 mL and 0.25 mL per kg of body weight of female fish and male fish, respectively. Fish spawned in double hapas in breeding tanks.
Results: The average fertilization, spawning, and hatching rates over 10 breeding cycles were 81%, 82%, and 85%, respectively. A total of 8.5 million fertilized eggs and 6.4 million hatchlings were produced. The survival of fry during larval rearing trials at a stocking rate of 500 hatchlings/m2 was 58% after 22 days. The mola hatchlings and fry were sold to 29 farmers at prices comparable to those of Indian major carp.
Discussion: This article makes a unique contribution to the literature by documenting the entire process of hatchery-based mass mola seed production, including broodfish collection and maintenance, hormone dose optimization, breeding arrangements, breeder characteristics, breeding behavior and performance fecundity, larval rearing, and seed sales to farmers. This information is intended to serve as a protocol to be followed by any individual or institution with an interest in mola breeding and represents an important contribution to the development of nutrition-sensitive aquaculture.PRIFPRI3Development Strategies and Governance (DSG); Transformation Strategie
Dataset of biological community structure in Deepor Beel using eDNA approach–A RAMSAR wetland of Assam, India
Deepor Beel, located in the state of Assam in India, is a Wetland of International Importance with a Wildlife Sanctuary and is the only RAMSAR site in the state. Though of invaluable ecological significance, the wetland is facing anthropogenic stressors, leading to rapid degradation of ecological health. In December 2022, surface water was collected from six stations of Deepor Beel to elucidate biological communities using the eDNA approach. At the time of sampling, in-situ environmental parameters were measured in triplicates. The dissolved nutrients and concentrations of metals and metalloids were estimated using UV–Vis Spectrophotometry and ICP-MS approaches respectively. The study revealed a high concentration of dissolved nitrate in the surface water. High-throughput sequencing using Nanopore sequencing chemistry in a MinION platform indicated the overwhelming abundance of Moraxellaceae (Prokaryotes) and Eumetazoa (Eukaryotes). The abundance of Cyprinidae were also encountered in the studied wetland reflecting the biodiversity of fish populations. High nitrate along with elucidated microbial signals are crucial to designate ecological health status of Deeper Beel. This study is aimed at generating baseline information to aid long-term monitoring and restoration of the Deepor Beel as well as the first comprehensive assessment of a RAMSAR Site located in northeast of India