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The administration of phage therapy for aquaculture disease has been anticipated by the researchers over a decade as an effective and an alternative control mechanism, though the application of phages as a disease control agent in aquaculture projects various beneficial aspects, critical limitations, and negative influence on production. This present scenario made a pressure to review the possible disclosure of phage therapy with its critical boundaries and limiting influences towards the disease control management of aquaculture (fish, shrimps, lobsters, bivalve mollusks, etc.). The phage therapy has proven its efficacy as a biocontrol agent towards aquaculture disease, although the sustainability of the phage therapy needs further investigation on the following: commercial application, formulation of bacteriophage for layman usage, and development of protocol for various diseases with consistent results. The marginal space existing between the inventors and the end user must be fulfilled by the awareness program and the government policies. The administration of the phage therapy could be effective for long-term safety and negatively influence the development of multidrug-resistant bacteria pathogens in the future.

Sponges are sessile benthic filter-feeding animals, which harbor numerous microorganisms. The enormous diversity and abundance of sponge associated bacteria envisages sponges as hot spots of microbial diversity and dynamics. Many theories were proposed on the ecological implications and mechanism of sponge-microbial association, among these, the biosynthesis of sponge derived bioactive molecules by the symbiotic bacteria is now well-indicated. This phenomenon however, is not exhibited by all marine sponges. Based on the available reports, it has been well established that the sponge associated microbial assemblages keep on changing continuously in response to environmental pressure and/or acquisition of microbes from surrounding seawater or associated macroorganisms. In this review, we have discussed nutritional association of sponges with its symbionts, interaction of sponges with other eukaryotic organisms, dynamics of sponge microbiome and sponge-specific microbial symbionts, sponge-coral association etc.

Indian aquaculture industry was growing steadily and showed a sixfold growth in production over the last two decades. However, the overall development of aquaculture in India did not reach the levels as projected due to frequent disease outbreaks and related issues. Shrimp and fish are predominantly affected by viruses including white spot syndrome virus, monodon baculovirus, hepatopancreatic parvovirus, viral nervous necrosis, white tail disease, and hypodermal and hematopoietic necrosis baculovirus that cause outbreaks across the countries. Owing to these viral pathogens, the production of aquaculture fishes and crustaceans has dramatically been dropped. There are no specific measures to control these viral infections since it causes mortality at all life stages of cultured aquatic organisms. Early detection of the diseases may be beneficial to prevent the spreading and mass mortality. In India, the Central Institute of Brackish Water Aquaculture has developed a non-invasive diagnostic tool for early and precise detection of monodon baculovirus infection in Indian tiger shrimp Penaeus monodon using SYBR Green-based real-time polymerase chain reaction (PCR) technique. More than twenty-five cell lines from freshwater, brackish water, and marine fish have been developed, characterized, and stored in C. Abdul Hakeem College for research and viral diagnosis. This review reveals the distinctive tools that are being used in aquaculture for the detection of pathogens and preventive measures. Advanced molecular methods such as nested PCR and SYBR Green-based real-time PCR are found to be sensitive and effective for the quantitation. Simple and inexpensive methods such as microscopic evaluation and histopathological analysis detects the progression of the disease. These assays can be used as a diagnostic method for emerging diseases in addition to avoid forthcoming of another.

The family Nodaviridae includes two genera, Alphanodavirus and Betanodavirus. The family name derives from the Japanese village of Nodamura where Nodamura virus was first isolated from Culex tritaeniorhynchus mosquitoes. Virions are non-enveloped and spherical in shape with icosahedral symmetry (T=3) and diameters ranging from 25 to 33 nm. The genome consists of two molecules of single-stranded positive-sense RNA: RNA1 and RNA2. The virion capsid consists of 180 protein subunits arranged on a T=3 surface lattice. Alphanodaviruses infect insects, whereas betanodaviruses are pathogens of fish. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Nodaviridae, which is available at www.ictv.global/report/nodaviridae.

The family Sarthroviridae includes a single genus, Macronovirus, which in turn includes a single species, Macrobrachium satellite virus 1. Members of this species, named extra small virus, are satellite viruses of Macrobrachium rosenbergii nodavirus, an unclassified virus related to members of the family Nodaviridae. Both viruses have isometric, spherical virions, infect giant freshwater prawns and together cause white tail disease, which is responsible for mass mortalities and severe economic losses in hatcheries and farms. Infection is caused by both vertical and horizontal transmission of virus. Aquatic insects act as a carrier to transmit the disease in prawns. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Sarthroviridae, which is available at www.ictv.global/report/sarthroviridae.

Sponges are closely associated with microorganisms that occur either intracellularly and extracellularly. Sponges are soft-bodied sessile organisms appear to be defenseless in facing predation. Microbial symbionts supposed to have a functional role in the host defense against pathogens, predation and microfouling processes. Recently, the ubiquitous defense enzyme, phospholipase A2 (PLA2) detected in the sponge associated bacterium envisaged the possible functional role in the ecological succession of host sponge against predatory / fouling pressure in the habitat. In present review, we highlighted the possible functional interactions between associated microbes and host sponges and its potentials in bioprospecting approaches.

As an alternative strategy to antibiotic use in aquatic disease management, probiotics have recently attracted extensive attention in aquaculture. However, the use of terrestrial bacterial species as probiotics for aquaculture has had limited success, as bacterial strain characteristics are dependent upon the environment in which they thrive. Therefore, isolating potential probiotic bacteria from the marine environment in which they grow optimally is a better approach. Bacteria that have been used successfully as probiotics belong to the genus Vibrio and Bacillus, and the species Thalassobacter utilis. Most researchers have isolated these probiotic strains from shrimp culture water, or from the intestine of different penaeid species. The use of probiotic bacteria, based on the principle of competitive exclusion, and the use of immunostimulants are two of the most promising preventive methods developed in the fight against diseases during the last few years. It also noticed that probiotic bacteria could produce some digestive enzymes, which might improve the digestion of shrimp, thus enhancing the ability of stress resistance and health of the shrimp. However, the probiotics in aquatic environment remain to be a controversial concept, as there was no authentic evidence / real environment demonstrations on the successful use of probiotics and their mechanisms of action in vivo. The present review highlights the potential sources of probiotics, mechanism of action, diversity of probiotic microbes and challenges of probiotic usage in shrimp aquaculture.

The present investigation aimed to evaluate the effect of feeding regimes composed of various combinations of live food (LF), artificial food (AF) and mixed food (MF: LF and AF 50% each) on the digestive physiology of first feeding Catla catla (catla) larvae. Larvae (0.92 ± 0.21 mg) were cultured for 30 days under six different feeding regimes of LF, AF, MF, two groups were shifted from LF to AF on day-13 (LF-AF-13) and day-18 (LF-AF-18) and one group from LF to MF on day-12 (LF-MF-13). Significantly (p