Establishment and Characterization of Eye Muscle Cell Line from Snow Trout, Schizothorax richardsonii (Gray, 1832), a Vulnerable Coldwater Fish, for In Vitro Studies

Schizothorax richardsonii, commonly called snow trout is a vulnerable coldwater fish distributed in India and adjoining countries, is an important resource as food, ornamental and game fishery. A cell line, designated as SREM-1, has been established from the eye muscle of S. richardsonii using explant method and cultured in Leibovitz’s L-15 medium. The growth studies at 20-32°C temperatures and 5-20% of fetal bovine serum (FBS) concentrations revealed that SREM-1 cells exhibited optimal growth at 28°C in L-15 medium containing 20% FBS. Cell type was confirmed primarily as epithelial in nature by immuno-phenotyping assay and was sub-cultured for >55 times since its development. The origin of the cell line was confirmed by sequencing of cytochrome oxidase c subunit I and 16S rRNA genes. SREM-1 cell line is free from mycoplasma contamination and has been cryopreserved at different passage levels with revival efficiency of 70-80% after 6 months. The SREM-1 cell line was successfully transfected and also employed for evaluating in vitro cytotoxicity against a heavy metal, mercuric chloride. The newly established cell line of this vulnerable species would be useful as a model for aquatic toxicological and transfection studies.

INFESTATION OF NEMATODE PARASITE FILOCHONA TELEOSTEI IN RELATION TO SIZE, WEIGHT AND AGE OF SNOW TROUT SCHIZOTHORAX RICHARDSONII (GRAY)

Parasitological investigation was conducted to assess the effects of various biotic factors viz. length, weight and age of host on the infection patterns of Filochona teleostei (Singh & Malik, 1992) in snow trout Schizothorax richardsonii (HAM.) from hill streams of Garhwal Himalayas. The statistical analysis was carried out to calculate infection incidence, mean worm burden, regression values and their significance. About 20% fishes (18% male and 22% female) were found infected with nematode parasites. Infection patterns of Filochona teleostei revealed a negative correlation (r= - 0.347 to - 0.734) with length, (r= - 0.499 to - 0.671) with weight and (r= - 0.576) with age of host fish. The age immunity and stronger host resistance developed by the larger fishes are the possible reasons for the decrease in infection in larger and older fishes.

STUDIES ON THE FEEDING OF SNOW TROUT, SCHIZOTHORAX RICHARDSONII (GRAY) BASED ON NATURAL AND ARTIFICIAL DIET

The present paper deals with food analysis and feeding behavior of the snow trout Schizothorax richardsonii (Gray) which is a cold water herbivore fish by nature. It is locally called Asela and is distributed in Himalayan and sub-Himalayan regions of Asia and has considerably attracted the attention of researchers due to its high productivity. The health and growth of fishes is greatly influenced by their nutrition and feeding. It has been observed in the present study that the adult fish naturally feeds on diatoms and algae. An experiment was conducted on artificial feeding of fish by giving three different types of food, i.e., formulated diet as control, periphton based diet and a mixture of both in different artificial raceways. It was observed that the fish conversion ratio (FCR) of the fish pooled in the raceway one (R1), i.e., feeding with formulated was high (6.85) due to balanced nutrients. It is recommended that with the introduction of balance artificial diet may be helpful in increasing the production of S. richardsonii.

Schizothorax richardsonii dsRNA dependent protein kinase has three double-stranded RNA binding motifs with a promoter lacking conserved kinase sequence

The authors have withdrawn this preprint due to author disagreement.