Prabhati Kumari Sahoo

Bio: Prabhati Kumari Sahoo is an academic researcher from Indian Council of Agricultural Research. The author has contributed to research in topics: Mahseer & Tor putitora. The author has an hindex of 8, co-authored 44 publications receiving 279 citations. Previous affiliations of Prabhati Kumari Sahoo include Central Institute of Freshwater Aquaculture.

Pathological findings of experimental Aeromonas hydrophila infection in Golden Mahseer (Tor putitora)

Abstract: a) Introduction: Mahseers, belong to the family Cyprinidae, are well renowned for the excellent game as well as food i¬shes. Various aspects simultaneously considered towards the domestication of this fish species also include the study of fish health issues, preventive and remedial programmes for sustainable aquaculture. Experimental studies can be conducted in the control condition to study the pathological symptoms during bacterial infection. Considering the bacterial pathogens as a major constraint for aquaculture, the present study was carried out to standardize the bacterial concentration of A. hydrophila for the experimental challenge of Golden Mahseer for the first time, and various clinical changes were also monitored during the infection. Materials and Methods: A total of 140 live fishes were acclimatized to the laboratory conditions for experimental study. A constant water quality was monitored during the acclimation period and throughout the experiment. The test group was injected with A. hydrophila and various physiological, biochemical and tissue level changes were observed during the experiment in comparison to phosphate buffer saline (PBS) injected control group. b) Results: LD50 value of A. hydrophila for Golden Mahseer was successfully standardized. Clinical signs including weakness, slower movement, swimming closer to the surface, fin haemorrhages and red patches at the gut region were observed. Enlargement of spleen followed by tissue necrosis along with signs of haemorrhagic septicaemia was also seen in infected fishes. The necrosis of hepatocytes was observed in the histological section of liver tissue. The bacterial infection increases the superoxide dismutase activity and cortisol level in Golden Mahseer. c) Conclusion: The LD50 value of A. hydrophila for experimental challenge studies on Golden Mahseer is 1.74 × 105 cfu per 100 g of body weight. The symptoms of severe bacterial haemorrhage were observed. Necrosis of hepatocytes was observed in infected fishes. The superoxide dismutase activity and cortisol level also increased in infected fishes. A. hydrophila was confirmed to be the etiological agent which was re-isolated using spread plate method and confirmed by 16s rRNA sequencing.

Transcriptional response to heat shock in liver of snow trout (Schizothorax richardsonii)—a vulnerable Himalayan Cyprinid fish

Abstract: The snow trout (Schizothorax richardsonii) belonging to family Cyprinidae, is an endemic fish of the Himalayan region. The species is tagged as vulnerable species in the IUCN red list of threatened species. The fish thrives well in snowmelt water of several streams and rivers in the region but are occasionally exposed to more than 20 °C during the summer season. Therefore, we have used deep RNA sequencing to decipher the transcriptome of snow trout and characterize the genes and molecular pathways involved in heat shock response. In this study 72,601,298 and 65,428,283 raw reads for heat-shocked and control, respectively, were obtained by Illumina paired-end sequencing technology. The de novo assembled transcriptome was tested for differential gene expression across the treatment groups. The quality of assembly was high with N75 and N50 lengths of 461 and 1274 bases, respectively. A total of 65 unique transcripts were differentially expressed in liver under heat shock and control. Annotated blast matches reveal that differentially expressed transcripts correspond to critical chaperones and molecular pathways, previously shown to be important for thermal stress in other fish species. Eight randomly selected heat-stressed responsive transcripts were also observed to be upregulated during qRT-PCR analysis. This study is the preliminary step to understanding the responses during sudden environmental changes like heat shock. The reference transcriptome database would also aid further studies on biological and physiological aspects of the snow trout under abiotic stresses.

Identification of RAPD markers, in situ DNA content and structural chromosomal diversity in some legumes of the mangrove flora of Orissa

Abstract: Randomly amplified polymorphic DNA (RAPD) markers, karyotypes and 4C DNA content were analyzed in five legume mangroves belonging to the sub-family Papilinoideae (Dalbergia spinosa, Derris heterophylla and D. indica) and Caesalpinioideae (Caesalpinia crista, Cynometra ramiflora) of the family Fabaceae to establish the genetic variability and phylogenetic affinities. Somatic chromosome numbers were reported for the first time in D. spinosa (2n = 20), C. ramiflora (2n = 26) and D. heterophylla (2n = 24) with reconfirmation of the somatic chromosome number in D. indica (2n = 22) and C. crista (2n = 24). Significant intergeneric and interspecific variation of 4C DNA content was observed and that varied from 8.970 pg in C. ramiflora to 28.730 pg in D. indica. From the RAPD analysis, the dendogram showed clustering of Caesalpinia crista and Cynomitra ramiflora into one group (81.80). In the second groups Derris indica and Derris heterophylla were more similar (83.10) than Dalbergia spinosa (85.80). Species-specific DNA markers (900 bp) obtained in D. spinosa from OPN15; 700 and 2000 bp in C. ramiflora from OPN4 and 400 and 800 bp in D. heterophylla and 500 bp DNA fragment in C. crista obtained from OPN-11 were found characteristic RAPD markers of these species. C. crista found more closer affinity to C. ramiflora of the sub-family Caesalpinioideae [genetic distance (1-F) = 0.847]. Derris indica showed closer genetic relation with D. heterophylla [genetic distance (1-F) = 0.856] than D. spinosa [genetic distance (1-F) = 0.876] where Derris and Dalbergia belongs to the sub-family Papilionoideae. By employing these markers the present study has helped to resolve the relationship between the taxonomically diverse leguminous mangroves and study their ability to coexist with mangroves that would shed light on the evolution of mangroves from terrestrial species.

The journal of genetics

Abstract: This is the oldest English language journal in genetics. Founded by W. Bateson and R. C. Punnett in 1910, the Journal of Genetics was later edited by J. B. S. Haldane; later, Haldane and his wife, Helen Spurway brought the journal with them to India. After his death in 1964, Mrs. Haldane continued publication of the journal, with Madhav Gadgil and H. Sharat Chandra (Indian Institute of Science, Bangalore) and Suresh Jayakar (Laboratorio de Genetica Biochimica ed Evoluzionistica, Pavia) as editors, until her own death in 1977. In 1985, with the permission of Haldane’s heirs, the Indian Academy of Sciences resumed publication of the journal. The journal retains its traditional interest in evolutionary research that is of relevance to geneticists, even if not explicitly genetic in nature.

Transcriptome Analysis Based on RNA-Seq in Understanding Pathogenic Mechanisms of Diseases and the Immune System of Fish: A Comprehensive Review

Abstract: In recent years, with the advent of next-generation sequencing along with the development of various bioinformatics tools, RNA sequencing (RNA-Seq)-based transcriptome analysis has become much more affordable in the field of biological research. This technique has even opened up avenues to explore the transcriptome of non-model organisms for which a reference genome is not available. This has made fish health researchers march towards this technology to understand pathogenic processes and immune reactions in fish during the event of infection. Recent studies using this technology have altered and updated the previous understanding of many diseases in fish. RNA-Seq has been employed in the understanding of fish pathogens like bacteria, virus, parasites, and oomycetes. Also, it has been helpful in unraveling the immune mechanisms in fish. Additionally, RNA-Seq technology has made its way for future works, such as genetic linkage mapping, quantitative trait analysis, disease-resistant strain or broodstock selection, and the development of effective vaccines and therapies. Until now, there are no reviews that comprehensively summarize the studies which made use of RNA-Seq to explore the mechanisms of infection of pathogens and the defense strategies of fish hosts. This review aims to summarize the contemporary understanding and findings with regard to infectious pathogens and the immune system of fish that have been achieved through RNA-Seq technology.