Asian Research Journal of Current Science

Aquaculture is increasingly expected to supply nutritious aquatic foods while reducing disease losses, antimicrobial dependence, feed-resource pressure and environmental emissions. Biotechnology is central to this transition, but evidence is fragmented across genetics, diagnostics, immunology, microbial ecology, feed science and production-system engineering. This critical narrative review evaluates how contemporary biotechnologies influence aquatic animal health and sustainability, with emphasis on farmed finfish and shellfish and on interventions that connect biological mechanism to measurable production or environmental outcomes. Literature published from 1 January 2000 to 30 May 2026 was identified through accessible scholarly indexes, bibliographic databases, institutional sources and citation searching, then appraised for methodological quality, field relevance, reproducibility and evidence-claim alignment. Genomic selection has the strongest translational record among advanced genetic approaches because it can increase disease resistance cumulatively without introducing a novel allele, although its benefit depends on representative challenge phenotypes and maintenance of genetic diversity. Genome editing offers precise functional validation and potential improvements in sterility, growth and resistance, but commercial health claims remain less mature than laboratory proofs of concept and require stringent off-target, welfare and ecological assessment. Molecular diagnostics, environmental nucleic-acid surveillance and vaccines can shift disease control towards prevention, yet sensitivity, sampling design, pathogen viability and delivery logistics constrain field interpretation. Probiotics, biofloc communities and bacteriophages can reduce pathogen pressure and support host function, but inconsistent strain characterisation and context-dependent performance limit generalisation. Feed biotechnology can decouple production from marine ingredients through microbial, insect and engineered oil resources, although life-cycle benefits depend on substrates, processing, digestibility and effects on product quality. Recirculating, aquaponic and integrated multi-trophic systems can recover nutrients and improve biosecurity, but transfer impacts to energy demand and operational complexity. The evidence therefore supports an integrated, risk-proportionate portfolio rather than a single technological solution. Future progress requires harmonised field endpoints, multi-site validation, genomic and microbial stewardship, transparent life-cycle accounting and governance that makes innovation accessible beyond highly capitalised production sectors.