Manoj Kumar Pati

Successful captive breeding of Caridina hodgarti, a native Indian ornamental freshwater shrimp, requires meticulous simulation of its natural stream habitat. This study details a standardized protocol for aquarium-based rearing and breeding, employing a 24″ × 18″ × 18″ tank setup with dark soil substrate, dual-stage sponge and canister filtration and stable temperature maintenance between 22–26°C. Habitat enrichment with aquatic plants, driftwood, rocks, and natural substrates enhanced survival rates and juvenile retention, while effective biological filtration and low-flow circulation maintained a stable ecological balance. Water quality was rigorously managed through routine testing and 25–30% weekly water changes, with a customized reverse osmosis (RO) and tap water mix to maintain pH levels between 6.5 and 7.5 and total hardness between 50 and 75 ppm. A diverse feeding regimen comprising spirulina-enriched pellets, blanched vegetables and natural detritus (almond leaves and driftwood) promoted healthy moulting, vibrant pigmentation and active foraging behavior. Reproductive indicators—including berried females and juvenile emergence—were consistently observed under these conditions, validating the system’s suitability for full life-cycle support. The results present a replicable model for ex situ conservation and commercial production of C. hodgarti, offering a sustainable alternative to wild stock collection in the ornamental aquaculture sector.

The Asian striped dwarf catfish, Mystus tengara is a freshwater tropical fish, inhabits both stagnant and flowing waters. This species is widely distributed in India, Bangladesh, Sri Lanka, Pakistan, Afghanistan, Nepal and Bhutan. Because of excellent nutritional content and delicious flavour, it has a strong market demand, positioning it as a potential candidate species for the aquaculture diversification in freshwater. The native population of this species has recently diminished due to over-exploitation and several unintended ecological alterations. A thorough understanding about biological characteristics of a species is essential for farming it. Numerous scientific investigations have studied various aspects of the biology of M. tengara, but there is a lack of information regarding its breeding, seed production and culture practices. The present review is aimed to highlight a consolidated picture of the status of general and reproductive biology, captive seed production as well as culture potential of this valuable species. This study will explore the scope of future research for the advancement of commercial aquaculture and conservation of the M. tengara.

The present investigation was undertaken to compare the morphometric correlations between major body components of male and female Caridina hodgarti (Kemp 1913), commonly known as the Green Rocket Shrimp, a freshwater atyid of ecological and aquacultural significance in India. Four morphometric traits—Total Length (TL), Carapace Length (CL), Abdominal Length (AL) and Rostrum Length (RL)—were measured from field-collected specimens and analyzed through linear regression models to evaluate inter-trait relationships and sex-linked growth variations. In males, weak to moderate positive correlations were recorded between TL and CL (R² = 0.1007), TL and AL (R² = 0.3666) and TL and RL (R² = 0.2001), while RL and CL also showed a moderate relationship (R² = 0.2175). A negative correlation between AL and CL (R² = 0.2274) indicated possible segmental trade-offs. In contrast, females exhibited stronger and more consistent proportional growth, especially between TL and AL (R² = 0.7008) and TL and RL (R² = 0.3229), whereas CL–AL (R² = 0.001) and RL–CL (R² = 0.0048) relationships were negligible. The results reveal marked sexual dimorphism in growth allometry, with females showing stable and reproductive-oriented body proportions, while males exhibited greater variability and segmental differentiation. This morphometric characterization provides useful baseline information for taxonomic identification, broodstock evaluation, population structure analysis and conservation management of freshwater atyid shrimps.

Di-(2-Ethyl-Hexyl) Phthalate (DEHP) is a plasticizer commonly found in aquatic environment due to wide use of plastics for various purposes. In this study, common carp (Cyprinus carpio) (length 14.2 ± 0.82 cm and weight 32.8 ± 0.66 g) were exposed to DEHP at three different concentration levels i.e., 10, 100 and 1000 ?g l-1 water for 30 d to find out its effect on certain haematological and histological parameters. Haematological studies revealed significant (p<0.05) decrease in erythrocyte counts, while leukocyte counts were significantly increased in treated group with increasing concentration of DEHP. Further, treatment of DEHP in concentration dependent manner showed deformities in erythrocytes whereas leukocytes were unaffected. The total plasma protein level was significantly (p<0.05) decreased in lower to higher concentration of the exposure. Histological studies showed gill and liver tissues were affected with impaired histoarchitecture in a dose dependent manner.

Phthalates (diesters of phthalic acid) are widely used as plasticizers and additives in many consumer products. Laboratory animal studies have reported the endocrine-disrupting and reproductive effects of phthalates and human exposure to this class of chemicals is a concern. Several phthalates including DEHP, BBP, DBP and etc. have been recognized as substances of high concern. This study aims to systematically review the literature on effects of exposure to phthalates including ovarian effects, testicular effects, effects on reproductive hormonal level as well as gene level and effects on breeding performances in fishes. Related literature search was done through Scopus, Google Scholar, Pub-Med and the reference lists of previous review articles to identify relevant articles published in each subject area. The inclusion criteria were original research, cross-sectional studies, case-control studies, interventional studies and review articles. The search was limited to English language papers. Finally, this review paper provides all current information on the hazards of various phthalate exposures on fish reproduction. The available data demonstrate that phthalate exposure is associated with reproductive disorders in both male and female fishes. Exposure of phthalates causes alteration in reproductive gene expression level as well hormonal level, changes in gamete quality parameters and also has impacts on spawning performances in both sexes.

Fish mortality generally occurs during extreme summer temperatures in India which are apprehended to be more frequent in near future and may reduce the fish population, particularly in closed aquatic systems. This present study is conducted with the objectives to find out heat shock and associated oxidative stress responses that occurred in selected fish Labeo rohita due to extremely high water temperature (treated, 37–38 °C against control, 28–30 °C) exposure for 2 weeks. Calculated mortality was 30% during the experimental period. The results revealed the biomolecules associated with both the anti-oxidative response (reduced glutathione in serum, liver, muscle; catalase activity in liver, muscle; superoxide dismutase gene expression in the liver) and the heat shock response (hsp70 gene expression in the liver) were elevated under thermal stress. Pro-inflammatory responses (expression of complement protein 3, glyceraldehyde 3-phosphate dehydrogenase in the liver) and oxidative damages (lipid peroxidation in all studied tissue and DNA fragmentation in the liver) were more under thermal stress. Extreme thermal stress induced by partial lethal temperature exposure in this study led to the activation of both the heat shock response and the anti-oxidative response. However, these responses were not elicited to the level so that they can protect from oxidative damages and inflammation in the liver of all the studied fish that caused partial mortality in fish. Thermal stress–induced hepatotoxicity caused fish death which was documented for the first time in freshwater fish.