Identification of polymorphic allozyme markers for population structure analysis in Horabagrus brachysoma (Gunther, 1864).

Fourteen polymorphic allozyme loci were identified in yellow catfish, Horabagrus brachysoma. The genetic variation detected at each allozyme locus was assessed for samples collected from three rivers. The observed heterozygosities per locus ranged from 0.0286 to 0.4000. Significant genotype heterogeneity indicated that the samples are not drawn from same gene pool. The results suggest the potential of the identified loci to analyze stock structure of natural populations of H. brachysoma

Low Genetic Differentiation in the Populations of the Malabar Carp Labeo dussumieri as revealed by Allozymes, Microsatellites and RAPD

The population structure of Labeo dussumieri, an endangered and endemic cyprinid from three riverine locations in the Western Ghats, India was investigated using allozyme, microsatellite and RAPD markers. L. dussumieri samples were obtained from Meenachil, Manimala and Pamba River basins, Kerala. Fourteen (46.7%) out of 30 allozyme loci, seven microsatellite loci and 12 RAPD Operon decamers gave polymorphic pattern. Six allozyme loci (AAT-2*, EST-4*, GLDH*, GPI-2*, G6PDH* and LDH-2*) and three microsatellite loci (LdussG1, MFW19 and Bgon22) exhibited consistent significant deviation from Hardy-Weinberg Equilibrium expectations in different populations after probability level (P<0.05) was adjusted for sequential Bonferroni correction. All the three marker types demonstrated concordant results and various estimates revealed genetic variability within the subpopulations but surprisingly low level (= 0.0034 to 0.0081) of genetic differentiation among L. dussumieri from different river samples. AMOVA analysis also indicated low differentiation among subpopulations. No evidence for a recent genetic bottleneck was observed in L. dussumieri populations based on allozyme and microsatellite data set analysis. Meenachil, Manimala and Pamba Rivers open in to the southern end of Vembanad Lake in Kerala and are connected to each other in the lower reaches through an extensive network of natural canals. Common ancestry in the prehistoric period; and possible mixing of fish populations resulting in high gene flow across the rivers through the lake and interconnecting canals could have been responsible for the lack of significant allelic heterogeneity among the L. dussumieri populations. The stocks from the three rivers do not require different management strategies and for propagation assisted river ranching programme of this species, large effective breeding population can be developed by mixing individuals from three river

DNA barcoding Indian marine fishes

DNA barcoding has been adopted as a global bio-identification system for animals in recent years. A major national programme on DNA barcoding of fish and marine life was initiated in India by the authors during 2006 and 115 species of marine fish covering Carangids, Clupeids, Scombrids, Groupers, Sciaenids, Silverbellies, Mullids, Polynemids and Silurids representing 79 Genera and 37 Families from the Indian Ocean have been barcoded for the first time using cytochrome c oxidase I gene (COI) of the mtDNA. The species were represented by multiple specimens and a total of 397 sequences were generated. After amplification and sequencing of 707 base pair fragment of COI, primers were trimmed which invariably generated a 655 base pair barcode sequence. The average Kimura two parameter (K2P) distances within species, genera, families, orders were 0.30%, 6.60%, 9.91%, 16.00%, respectively. In addition to barcode-based species identification system, phylogenetic relationships among the species have also been attempted. The neighbour-joining tree revealed distinct clusters in concurrence with the taxonomic status of the species

Pattern of hepatitis B and C infection among gravid women and their newborns in a tertiary care infirmary in India

Background: The objective is to determine the prevalence of the hepatitis B and C virus among pregnant women, to assess impact of maternal hepatitis B virus (HBV) or hepatitis C virus (HCV) carrier status on pregnancy outcomes and to gauge the risk factors associated with them. Antenatal clinic attenders and women undergoing termination of pregnancy over three years.Methods: The study was conducted in Gian Sagar Medical College & Hospital, Patiala, Punjab, India. Hepatitis B antigen and Hepatitis C virus antibody testing of sera from specimens sent to the hospital laboratory for routine serological testing. The results were then linked to risk information, obstetric complications and pregnancy outcome.Results: Overall HBsAg and anti-hepatitis C antibody prevalence was 1.2% (33/2031). Increased risk of transmission was associated with sexually transmitted diseases and previous surgical procedures. High rates of preterm labor pains, CD (27.27%), and non-reassuring fetal heart rate patterns and meconium stained liquor were found in the seropositive patients.Conclusions: Maternal hepatitis B and C carrier status is an eminent risk factor for adverse pregnancy outcome.

The Magnetic Primitive Library: A Platform for Designing Shape-Changing Interactions

This demonstration introduces the Magnetic Primitive Library (MPL) as a platform for hands-on exploration of programmable magnetic materials in interaction design. The MPL consists of a collection of magnetically actuated structures, each documented through domain configurations, fabrication guides, and visual notations. These primitives enable designers to engage with dynamic material behaviors by folding, programming, and activating silicone composites embedded with neodymium powder. We present the MPL as a platform for playful, hands-on material interaction, combining research-through-design with interdisciplinary material science. Through developing and demonstrating the library, we reflect on how the MPL fosters aesthetic ambiguity, curiosity, and material literacy, supporting designers in prototyping shape-changing interactions beyond functional outcomes

Ontogeny of the digestive tract in stinging catfish, Heteropneustes fossilis (Bloch) larvae

Heteropneustes fossilis (Bloch) is an important candidate species for diversification of freshwater aquaculture in India. However, high mortality rate during larval rearing is the most serious bottleneck in commercial production of this species. A proper understanding of the ontogenic development of digestive system provides the basis to understand the nutritional physiology of larvae and develop appropriate feeding strategies. In the present study, the ontogenical development of the digestive tract in H. fossilis larvae was studied from hatching until 30 day post-hatching (dph) at 29 °C. At hatching (2.8 ± 0.2 mm standard length, SL), the digestive tract was undifferentiated and attached dorsally to the yolk sac. At 1 dph (2.9 ± 0.2 mm SL), the mouth opened and oral valves were visible. At 2 dph (3.0 ± 0.3 mm SL), goblet cells were observed in the buccoparyngaeal cavity. At this age, exogenous feeding started and the intestine was differentiated into the anterior and posterior regions, and the rudimentary liver and pancreas were also seen. Small supranuclear vacuoles were observed in the enterocytes of the posterior intestine at 2 dph. Zymogen granules were observed in acinar cells of pancreas by 3 dph, and islets of Langerhans were visible at 4 dph (3.5 ± 0.1 mm SL). At the same age, most of the yolk sac reserves were consumed, whereas they were completely exhausted by 5 dph (3.9 ± 0.5 mm SL). Between 4 and 6 dph, the liver elongated in size and started to accumulate lipids in the hepatocytes. Gastric glands were detected at 4 dph, and the pyloric sphincter was completely differentiated at 9 dph (6.1 ± 0.4 mm SL) as an epithelial fold that separated stomach from the anterior intestine. By 13 dph (8.6 ± 0.2 mm SL), profuse gastric glands were visible inside longitudinal mucosal folds of the stomach. The formation of gastric glands and their development were noticed as the last events in the development of the digestive tract in H. fossilis. This indicated the end of the larval period and the commencement of the juvenile stage. Considering these observations, it is suggested that H. fossilis larvae have a morphologically complete digestive tract by 13 dph. The findings of the study on the development of the digestive system in H. fossilis may help in synchronising the larval stage of development and feeding strategies and would be helpful in improving larval rearing techniques for catfish species.info:eu-repo/semantics/acceptedVersio

Molecular insights into the mechanisms of susceptibility of Labeo rohita against oomycete Aphanomyces invadans

Aphanomyces invadans, the causative agent of epizootic ulcerative syndrome, is one of the most destructive pathogens of freshwater fishes. To date, the disease has been reported from over 160 fish species in 20 countries and notably, this is the first non-salmonid disease that has resulted in major impacts globally. In particular, Indian major carps (IMCs) are highly susceptible to this disease. To increase our knowledge particularly with regards to host immune response against A. invadans infection in a susceptible host, the gene expression profile in head kidney of A. invadans-infected and control rohu, Labeo rohita was investigated using RNA sequencing. Time course analysis of RNA-Seq data revealed 5608 differentially expressed genes, involved among others in Antigen processing and presentation, Leukocyte transendothelial migration, IL-17 signaling, Chemokine signaling, C-type lectin receptor signaling and Toll-like receptor signaling pathways. In the affected pathways, a number of immune genes were found to be downregulated, suggesting an immune evasion strategy of A. invadans in establishing the infection. The information generated in this study offers first systematic mechanistic understanding of the host-pathogen interaction that might underpin the development of new management strategies for this economically devastating fish-pathogenic oomycete A. invadans

Current Status of Knowledge on Hilsa

Species of the family Clupeidae are highly preferred food fishes in the world. The Indian shad, hilsa, belonging to the family Clupeidae, contribute to commercial catches in a number of countries bordering the Bay of Bengal, Indian Ocean, Persian Gulf and Arabian Sea. The species normally inhabit rivers, estuaries and coastal waters. The highest catch comes from the deltaic region of the Gangetic system in the coastal Bay o f Bengal. The fish is anadromous; grows and matures in the sea and migrates to freshwater fo r spawning. Hilsa fisheries provides direct and indirect livelihood to millions o f fishers along the coastal and riverine stretches in its range of distribution. They are highly delicious, priced and has important sociocultural importance, especially in West Bengal and the north eastern States of India. On account of its commercial importance and migratory habit, hilsa received research attraction since 1907 and there is a wealth of disseminated literature on various aspects o f hilsa by researchers o f different countries, including India