Nanotechnology is the understanding and control of matter at a scale of roughly 1–100 nm, where a unique phenomenon enables novel applications. Nanoparticles have unique properties due to their high specific surface area and a fraction of surface atoms, roughly 40–50%, and have an extraordinary potential for reactivity (Pournori et al. 2017). Therefore, nanomaterials have attracted much attention for their distinct properties unavailable in conventional macroscopic materials (Annamalai & Nallamuthu 2016). Due to their unique properties, nanomaterials have diverse applications in areas such as electronics, medical devices, cosmetics, food packaging, water treatment, fuel cells, biosensors, and environmental remediation. This has led to the production of nanomaterials on a large scale. Aquaculture nanotechnology can revolutionize the aquaculture field with its application to rapid disease detection, DNA vaccines, nutrient delivery, water filtration, water purification, water quality monitoring, construction materials, nanomedicine, and nano-sensors can be used to monitor aquaculture practices and improve fish health.
Silver nanoparticles are one of the most exploited nanomaterials owing to their germicidal and anti-inflammatory properties; they are used in burn treatment, socks, detergents, soaps, water, and air filters, bedding, and other medical and industrial textiles (Bar-Ilan et al. 2009). About 30% of nanoproducts are known to contain silver nanoparticles (Khan et al. 2015). The stabilization of AgNPs becomes a challenging research area because of their high active surface atoms, the aggregation, and deactivation by secondary nucleation and recrystallization and hence restricting their wide industrial applications. The majority of nanoparticle synthesis methods depend on the use of chemical capping agents like surfactants, polymers, and thiols (Niu and Li 2014), which have a strong interaction with the surface of AgNPs and hence act as good stabilizing agents. However, these chemical capping agents are nonbiodegradable, toxic, and difficult to detach from the surface of the nanoparticles. There is always a pressing need to explore green capping agents in order to secure the biological system and the environment (Sharma et al., 2019).
In the present scenario of climate change, the temperature of water bodies increases, which leads to increases in the toxicity of pollutants (Kumar et al. 2017). Heavy metals such as cadmium are known to increase in toxicity with an increase in temperature (Guinot et al. 2012), which in turn affects the physiological function of the fish, such as thermal tolerance, growth, metabolism, food consumption, reproductive success, and the ability to maintain internal homeostasis are adversely affected. When applied within the permissible limits of tissue retention, silver nanoparticles provide protection and benefit and do not pose any threat to environmental hazards (Chakraborty et al. 2013). Silver nanoparticles provide protection against Aeromonas veronii biovar sobria, high temperature, and Pb toxicity when used at 0.5 mg/kg feed (Kumar et al. 2018).
The production of meat from farm to table produces waste at various stages. The processing procedure of animals such as cows, sheep, goats, pigs, chickens, and turkeys leave litter such as bones, hides, and blood. The meat/edible portion of a cow accounts for 50–54%, sheep/goat 52%, pig 60–62%, chicken 68–72%, turkey 78%, and the other portion is turned into waste (Jha and Prasad 2016). The waste produced from the processing house or abattoir is left or thrown into the environment; if left unutilized, the waste creates unappealing and unhygienic surroundings. The use of certain animals and their byproducts for the synthesis of nanoparticles has been done, i.e., cockroach (Jha and Prasad, 2013), fish scales of Labeo rohita (Sinha et al. 2014), cobweb (Lateef et al. 2016), goat fur (Akintayo et al. 2020). With only 52% of the pig meat consumed for human consumption, effective utilization of the waste material to produce nano products via the biological method and an understanding of the product are required prior to its application. Several studies on the ecotoxicity of nanoparticles were undertaken on different species, like Labeo rohita, Lates calcarifer, Channa striatus, Pangasianodon hypophthalmus, Zebra fish, etc. Ecotoxicity analysis in the present study was carried out on Pangasianodon hypophthalmus fingerling as it is one of the most cultured species globally owing to its high growth rate, increased disease resistance, good taste, high resistance to poor water quality, and ability to survive in high stocking densities. A proposed study was carried out on pig waste, especially intestine thrown out as a waste product for the synthesis, characterization, bactericidal activity, and evaluation of the toxicity of the biosynthesis of silver nanoparticles on the physiological stress response activity of Pangasianodon hypophthalmus in the presence of abiotic stressors.