Papers by Sushilkumar Sarmah
Rasbora daniconius commonly known as slender Rasbora is a lower risk threatened species in Assam.... more Rasbora daniconius commonly known as slender Rasbora is a lower risk threatened species in Assam. Though the population is not at risk presently but the natural population is showing a declining trend due to habitat loss as well as anthropogenic stress. The species is a potential ornamental fish. Therefore the present studies elucidates the embryonic and the larval development of Rasbora daniconius from fertilization to juvenile stage. The most important criteria for breeding programs are-in-vitro sexual dimorphism selection of brooders, male and female ratio for breeding. In males colouration is bright and the lateral band is prominent whereas the females are fainter. The ratio of male to female is 1:1 or 2:1. The fish is bred by striping and artificially fertilized. The fertilized eggs are spherical, semi adhesive and the diameter of egg proper ranges between 0.8-1.0 mm × 0.96 mm. First sign of cleavage is observed at 20m from hatching, the appearance of germ plug commences the start of gastrula at 7h and organogenesis starts at 10h 30m after fertilization. The period of incubation is about 32h at a room temperature. The hatching percentage varied from 75% to 80%. The hatched larva is c 3.0 mm to 3.2mm in length. The yolk absorption is completed in five days from the day of hatching. The larva metamorphosed into juvenile within 25 days of hatching. The study will help aquaculturist and researchers to generate knowledge about the different developmental stages of the test species. It will also help to formulate feeding schedule for fries by aquarists.
International Journal of Fisheries and Aquatic Studies, 2014
The present study was undertaken to trace precisely the spawning period of an important ornamenta... more The present study was undertaken to trace precisely the spawning period of an important ornamental fish species, Brachydanio rerio. Gonadosomatic index (GSI) expresses the relative change in gonad weight to the percentage of body weight. In the present study two peaks are observed in the GSI of Brachydanio rerio, first peak is observed in the month of June and the second in the month of October.
Fisheries and Aquaculture Journal, 2015
North eastern region (NER) of India harbours 266 species of fishes out of which 196 have potentia... more North eastern region (NER) of India harbours 266 species of fishes out of which 196 have potential ornamental value. The present paper incorporates the technique of mass propagation of indigenous ornamental fish species with Danio aequipinnatus as the test species. For successful mass propagation of D. aequipinnatus, selection of brood stock, food and feeding schedule and breeding set-up are important criteria. Maintenance of physic-chemical parameters of the breeding tank is important in the survival of the breeders. Best fertilization rate were obtained with 3:2 male to female ratio.
Biological forum- An International Journal, 2019
Rasbora daniconius commonly known as slender Rasbora is a lower risk threatened species in Assam.... more Rasbora daniconius commonly known as slender Rasbora is a lower risk threatened species in Assam. Though the population is not at risk presently but the natural population is showing a declining trend due to habitat loss as well as anthropogenic stress. The species is a potential ornamental fish. Therefore the present studies elucidates the embryonic and the larval development of Rasbora daniconius from fertilization to juvenile stage. The most important criteria for breeding programs are-in-vitro sexual dimorphism selection of brooders, male and female ratio for breeding. In males colouration is bright and the lateral band is prominent whereas the females are fainter. The ratio of male to female is 1:1 or 2:1. The fish is bred by striping and artificially fertilized. The fertilized eggs are spherical, semi adhesive and the diameter of egg proper ranges between 0.8-1.0 mm × 0.96 mm. First sign of cleavage is observed at 20m from hatching, the appearance of germ plug commences the start of gastrula at 7h and organogenesis starts at 10h 30m after fertilization. The period of incubation is about 32h at a room temperature. The hatching percentage varied from 75% to 80%. The hatched larva is c 3.0 mm to 3.2mm in length. The yolk absorption is completed in five days from the day of hatching. The larva metamorphosed into juvenile within 25 days of hatching. The study will help aquaculturist and researchers to generate knowledge about the different developmental stages of the test species. It will also help to formulate feeding schedule for fries by aquarists.
International Journal of Fisheries and Aquatic Studies, 2015
North eastern region (NER) of India harbours 266 species of fishes out of which 196 have potentia... more North eastern region (NER) of India harbours 266 species of fishes out of which 196 have potential ornamental value. The present paper incorporates the technique of mass propagation of indigenous ornamental fish species with Danio aequipinnatus as the test species. For successful mass propagation of D. aequipinnatus, selection of brood stock, food and feeding schedule and breeding setup are important criteria. Maintenance of physic-chemical parameters of the breeding tank is important in the survival of the breeders. Best fertilization rate were obtained with 3:2 male to female ratio.
Uploads
Papers by Sushilkumar Sarmah