Red sea bream iridovirus (RSIV) is an emerging viral pathogen having significant socio-economic and environmental impacts on marine and brackish aquaculture systems. The study documents certain interesting findings of an RSIV disease outbreak that caused 50% cumulative mortality among cage farmed Asian sea bass in India. The confirmatory diagnosis was made based on internationally approved protocols. The affected fish showed splenomegaly, anaemia, and abnormally enlarged cells within the spleen, liver, kidney, and brain. The consistent presence of two fish pathogens, viz., Vibrio alginolyticus and Vibrio fluvialis, in the liver, along with characteristic vibrio-induced pathologies were noted, indicating the possible role of these bacterial pathogens in RSIV pathogenesis during the outbreak. More strikingly, the surviving fish were found to carry the virus even after two months post-outbreak, warranting future investigations on the carrier status of RSIV survivors.

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Copepods are a critical live prey item for most marine finfish larvae in the natural environment. The calanoid copepod belonging to species Acartia is a potential live food for the larval rearing of marine finfishes because of their higher productivity and tolerance to wide range of salinities. The present study was conducted to determine the effect of salinity on production parameters to standardize the optimal salinity for Acartia bilobata culture. For selecting the optimal salinity range, the adult copepods were exposed to abrupt salinity change from 30 g L?1 to ten salinity levels, including 0, 5, 10, 15, 20, 25, 30, 35, 40 and 45 g L?1 and their survival estimated after 24 h. Further, the effect of salinity (15, 20,25,30, and 35 g L?1) on egg production, hatching success and population growth were studied. 

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Trachinotus blochii is a promising mariculture fish species. Scientific data on biosafety and fillet residues of florfenicol exposure, one recommended amphenicol antimicrobial for aquaculture use, remains unknown in T. blochii, despite its criticality for prudent application. Accordingly, the paper evaluated the safety (regarding mortality, symptoms, weight gain, and histopathology) of dietary florfenicol after therapeutic (10 mg Kg-1 for ten days) and excessive (three, five, and ten times the therapeutic dose for 10, 20, and 30 days) exposures. There was no mortality in any group. The clinical abnormalities were noted only in 10X group from the 25th exposure day, which disappeared on the fourth day after withdrawal. Reduced growth was recorded at 5X and 10X groups from 20 and 30 exposure days, respectively.

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Sulfated polysaccharides are effective immunostimulating agents by activating several intracellular signaling pathways. A sulfated (1 ? 3)/(1 ? 4)-linked galactofucan TCP-3 with promising immunomodulatory effects was purified from a marine macroalga Turbinaria conoides. The immune-enhancing potential of TCP-3 (100–400 mg/kg BW) was evaluated on cyclophosphamide-induced immunosuppressed animals by increasing bone marrow cellularity (10–13 cells/femur/mL x 106), ?-esterase activity (1200–1700 number of positive cells/4000 BMC), interferon-? (1.31–1.49 pg/mL), interleukin-2 (3.49–3.99 pg/mL) secretion, and WBC count (> 3000 cells/cu mm). The proliferation of lymphocytes for in vitro and in vivo conditions was enhanced by administering TCP-3 besides regulating the secretion of pro-inflammatory cytokines (interleukin-6/1?/12, tumor necrosis factor-?, transforming growth factor-?), and an inducible isoform of nitric oxide synthase.

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The present study reports the comparative pharmacokinetic profiles of florfenicol and its metabolite (florfenicol amine, FFA) in Trachinotus blochii under tropical marine conditions (salinity: 35?±?1.4‰; temperature: 28.8?±?0.54 °C) following a single in-feed oral administration of the recommended dose (15 mg/Kg). Furthermore, the study investigated the distribution of these two compounds in nine different tissues. The maximum florfenicol concentrations (Cmax) in plasma and tissues were observed within five hours (Tmax), except for bile. The Cmax ranged from 572 to 1954 ng/g or ml and was in the intestine?>?bile?>?muscle?+?skin?>?liver?>?gill?=?heart?>?plasma?>?kidney?=?spleen. 

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Purpose: The present study describes a new species of myxosporean, Sphaeromyxa cornuti n. sp. infecting the gallbladder of the Moorish idol, Zanclus cornutus (Linnaeus 1758) collected from Lakshadweep waters of the Arabian Sea. Methods: Fish were collected using traps and cages. The morphology of mature spores recovered from the gallbladder of Z. cornutus was studied under Nomarski Differential Interference Contrast (DIC) optics. The molecular and phylogenetic analyses were based on SSU rDNA. Results: Sphaeromyxa cornuti n. sp. is characterized by arcuate myxospores with tapering extremities and round ends in valvular, and slightly sigmoid in sutural views (19.2–24.7 µm?×?4.1–5.7 µm). The two polar capsules are unequally elongate-ovoid in shape and positioned at opposite ends of the spore (6.2–9.7 µm?×?1.7–2.6 µm). Each encloses an irregularly folded, ribbon-like polar tubule, which is oriented parallel to polar capsule axis.

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Seaweed-associated bacterial symbionts are sources of potential pharmacological properties. The present study resulted in the culture-dependent isolation of bioactive heterotrophs belonging to the bacterial phylum Firmicutes, which were dominated more than 30% of the 127 cultivable isolates, amongst which 23 of them showed potential antimicrobial activities against a wide range of pathogens. The symbionts isolated from the seaweed Sargassum wightii showed significant bioactivity. Those were characterized as Bacillus safensis MTCC13040, B. valismortis MTCC13041, B. velezensis MTCC13044, B. methylotrophicus MTCC13042, Oceanobacillus profundus MTCC13045, B. tequilensis MTCC13043, and B. altitudinis MTCC13046. The organic extracts of the studied isolates showed potential antimicrobial properties against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci (minimum inhibitory concentration 6·25–12·5??g?ml?1). The organic extract of B.

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Deep-water shrimps are non-conventional culinary delicacies due to the presence of essential nutrients, although they are predominantly unexplored marine fishery resources. The nutritional composition of deep-water shrimp species Aristeus alcocki, Heterocarpus chani, Plesionika quasigrandis, Solenocera choprai, and Metapenaeopsis andamanensis captured from Arabian Sea (southwest coast of peninsular India) was determined. The shrimp demonstrated a well-composed essential/non-essential amino acids ratio (0.76-0.84). Among other deep-water shrimps, protein content, total aromatic, and sulfur-enclosing amino acids were substantially higher in A. alcocki (12.69 g 100 g-1, 344 and 270 mg 100 g-1 wet tissue, respectively). The C20-22n-3 polyunsaturated fatty acid analogues (docosahexaenoic and eicosapentaenoic acid) were found to be in appreciable quantities (82-130 and 56-120 mg 100 g-1 wet edible portion, respectively) in the studied deep-water shrimp species. Lower thrombogenicity and atherogenicity indices (0.16-0.32 and 0.35-0.53, respectively) acknowledged the studied deep-water shrimp species as valuable health food items for cardioprotection and anti-platelet aggregation.

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Orange chromide, Pseudetroplus maculatus is a euryhaline species with both ornamental and food  value. The species  has several attributes similar to other fish model organisms such as smaller size, repeated breeding, ease of maintenance, and higher fecundity. A salinity tolerance study was performed in different salinities (0, 15, and 35 ppt) in triplicate introducing 10 fishes each (5.4 ± 0.08 g) in 12 plastic tanks of 60 L water-holding capacity. Fish were fed with commercial feed (1.2 mm and 40% protein) at 5% of body weight twice daily for 45 days. No significant variation (p< 0.05) in growth and survival was observed during the study indicating the wide salinity tolerance for the species. Experimental breeding of the species in freshwater and seawater (35 ppt) revealed the ability of the species to breed in varying salinities. Lenience in captive broodstock development, pair formation, and year-round natural breeding makes the seed production of the species easier.

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A multiple-choice feeding experiment was conducted on the two sea urchins, viz., Salmacis virgulata and Temnopleurus toreumaticus, in four feeding assays with 12 varieties of seagrass and seaweed. The results of the study have revealed that the species Caulerpa peltata, C. racemosa, Kappaphycus alvarezii and Padina tetrastromatica occupied the top feeding positions in the descending order for S. virgulata. But for T. toreumaticus, the order of preference was observed to decrease sequentially for C. peltata, Cymodocea serrulata, C. racemosa and Syringodium isoetifolium. This study further revealed that there was a leaning preference towards seagrass species in T. toreumaticus which was conspicuously absent in S. virgulata. This kind of studies would pave way to better understand sea urchin ecology and its urchin barren phenomenon.

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The present study reports the first record of Bengal reticulated puffer, Chelonodontops bengalensis from Odisha coast in the northwestern Bay of Bengal based on two specimens (226 – 301 mm SL), each collected from Paradeep and Bahabalpur in 2018 and 2019, respectively. The detailed morphological features of C. bengalensis are provided and compared with its previous records. The species is distinguished from its congeners by having 12 dorsal fin rays, 10 anal fin rays, 18 – 19 pectoral fin rays, 10 – 11 caudal fin rays, nasal organ cup shaped with unequal sized flaps, and dorsal profile of body covered with white spots of various shape and size and ventral side silvery white. Our study indicated the range extension of C. bengalensis from its known geographical range i.e. Bangladesh and West Bengal towards south in the northern Bay of Bengal.

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