Aquaculture encompasses two key areas: disease management and healthcare provision. In the aquaculture sector, diseases are the main source of financial loss, hence managing diseases is essential to long-term profit.
Many aquatic consumers, including fish, corals, amphibians, zooplankton, and crustaceans, are stressed by ultraviolet-B (UV-B) radiation. Avoidance tactics, repair systems, and the manufacture of UV-absorbing materials are the main forms of protection for many aqua producers and consumers. Life as we know it depends on the health of freshwater and marine ecosystems. Sun UV-B radiation is one possible stressor that might be detrimental to the health of some animals in these habitats. There might be significant ramifications for a range of aquatic species, including waterborne human infections, as a result of other anthropogenic stressors such as pollution that changes UV exposure levels in inland and coastal marine waters.
Immunostimulants are a helpful prophylactic for managing disease in cultured animals. It enhances fish health and lessens the negative effects of environmental stress. Immunostimulant-induced non-specific immune system activation confers resistance against a range of infections. Food-based immunostimulant administration is a successful strategy due to its quick delivery and straightforward access points. Plant-based compounds have recently attracted more attention as potential immunostimulants. These are inexpensive, environmentally friendly, biocompatible, and biodegradable. Numerous research conducted in lab settings demonstrates the beneficial effects of plant-based components on various fish species. Immunostimulants are a helpful prophylactic for managing illness in cultured animals. It enhances fish health and lessens the negative effects of environmental stress. The immunostimulant non-specifically stimulates the immune system.
One effective prophylactic strategy for managing illness in cultured animals is the use of immunostimulants. It enhances the health of fish by lessening the effects of environmental stress. By non-specifically stimulating the immune system, the immunostimulant confers resistance against a wide range of infections. Due to its quick distribution and easy access points, immunostimulant administration through food is a successful strategy. The use of plant-based substances as immunostimulants has garnered more attention recently. They are economical, environmentally benign, biocompatible, and biodegradable. The beneficial effects of plant components on many fish species have been demonstrated by several research conducted in lab settings. In order to effectively apply the priceless natural goods, it is necessary to assess the immunostimulatory qualities of the plant constituents in aquatic circumstances.
The UV-B protective properties of Achyranthes aspera were evaluated in Clarias batrachus. Fish were fed with four diets of leaves and seeds including control feed. After the experimental duration of feeding, fish were exposed to UV-B and one batch of fish in each treatment was kept unexposed. Significantly higher final weight was found in seeds followed by leaves treatments. Among exposed fish, significantly higher lysozyme was found in seeds and myeloperoxidase in seeds and leaves compared to others. Nitric oxide synthase and superoxide dismutase levels were significantly higher in the liver and head kidney of seeds diet-fed fish compared to others. Thiobarbituric acid reactive substances and carbonyl protein levels were minimal in seeds followed by leaves. There was up-regulation of various gene markers in the liver and head kidney of leaves and seeds incorporated diets fed fish compared to the control.
The immunostimulatory properties of seeds and leaves of Achyranthes aspera (Linn.) was evaluated in rohu Labeo rohita in the pond conditions. Rohu fry was introduced in nine hapas set inside a pond. Two test diets enriched with seeds and leaves of A. aspera and a control diet were fed for 60 days. Then fish were immunized with chicken-RBC and blood and tissue samples were collected on various days after immunization. The average weight was significantly higher in the seeds diet-fed rohu compared to the other two feeding regimes.
The SGR and FCR were maximum and minimum in seeds diet-fed rohu. Serum lysozyme, myeloperoxidase, and NOS levels were higher in seeds diet-fed rohu compared to others. Significantly TBARS and carbonyl protein levels were found in seeds fed rohu compared to others. There was significant up-regulation of lysozyme C, lysozyme G, and TNF-α in the hepatopancreas of rohu fed with seeds diet compared to others. In enriched diets fed rohu, the expression of IL-10 was lower compared to the control fish. Toll-like receptor 4 was significantly higher in seeds and leaves diets fed rohu compared to the other two feeding regimes on day 7 and day 21 after immunization, respectively.
Seeds and leaves enhanced the growth, induced the immune system of rohu, and gave protection against oxidative stress in pond conditions. Seeds are more efficient compared to the leaves. The information generated from the field study has practical utility. This was confirmed from the present pond or laboratory study both seeds and leaves of Achyranthes aspera enhanced the growth of rohu, induced the immune system, and prevented tissue from oxidative damage. Though seeds performed better compared to the leaves still leaves showed promising results. The information generated from the field study has aquacultural applications.
