Can sympathetic induction be a convenient technique for breeding Amblypharyngodon mola (Hamilton, 1822)?

Mola carplet (Amblypharyngodon mola) is one of the most popular small fish species of the Indian subcontinent. There are limited studies on captive breeding of this species, which is important for aquaculture and the conservation prospects of this species. The conventional induced breeding method using an inducing agent (GnRHa and dopamine antagonist) is one of the most effective and prevalent methods of breeding fish. It is a laborious and time-consuming process, particularly in mass fish breeding and in lieu of that, a less time-consuming method - sympathetic induction of the broodstock, is used in some regions of India, particularly in big carp fish. However, this method has not been reported in commercial-scale breeding of small indigenous fish species. Therefore, an experiment was conducted to compare the spawning efficiency of Amblypharyngodon mola bred by sympathetic induction with the conventional complete induced breeding method. The spawning performance in terms of latency period, relative fecundity, fertilization rate, incubation period, and hatching rates of sympathetically induced Amblypharyngodon mola were compared to completely induced Amblypharyngodon mola brooders. Although the latency period (7.8 hrs), relative fecundity (39 nos./g), fertilization rates (81.61%) and spawning efficiency coefficient (0.681) were better in conventionally induced fish, but lower post-spawning mortality (1.29%) and better hatching rates (86.21%) were observed in sympathetically induced fish. The results indicate that quality offspring of Amblypharyngodon mola could be obtained in terms of survivability through sympathetic breeding. Sympathetic induction breeding could be a cost-effective, convenient, time-saving method of mass-scale breeding and aquaculture of Amblypharyngodon mola.

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.