Whiteleg shrimp (Litopenaeus vannamei) are essential for the aquaculture industry and the global economy. However, their health and disease resistance can be challenged by various factors, including bacterial infections such as those caused by Vibrio harveyi.
In this context, science is constantly advancing in search of effective solutions to improve the health and resilience of these species. A research team from Pondicherry University, Periyar University, and Bharathiar University focused on the use of chitosan nanoparticles loaded with vitamin C (VC-CSNPs) as a dietary supplement for whiteleg shrimp, yielding promising results that could revolutionize the aquaculture industry.
The study aimed to determine the effect of dietary supplementation of vitamin C-loaded chitosan nanoparticles on antioxidant activity, disease resistance, non-specific immunity, and gene expression in Litopenaeus vannamei shrimp, which were fed for eight weeks and challenged with Vibrio harveyi.
Nanotechnology in Aquaculture
Nanotechnology has emerged as a promising field for improving the health and resilience of aquatic organisms. Chitosan is widely used in fields such as agriculture, aquaculture, and medicine.
Chitosan is used in aquaculture as an immunostimulant that can protect shrimp and cultured fish from pathogens. Chitosan biopolymer is biocompatible, less toxic, and easily degradable.
In this study, natural chitosan nanoparticles were used to deliver vitamin C, a crucial antioxidant. The combination of these two substances was designed to increase the bioavailability of vitamin C and strengthen the shrimp’s immune system.
Methodology and Characterization of Nanoparticles
VC-CSNPs were prepared using the ionotropic gelation method and were characterized using techniques such as Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Zetasizer analysis.
The results confirmed the formation of spherical VC-CSNPs with an average particle size ranging from 95 to 100 nm and a positive zeta potential of +29.84 mV. This characterization ensured the quality and stability of the nanoparticles used in the study.
Impact of VC-CSNPs on Shrimp Health
The study was conducted over eight weeks, during which whiteleg shrimp were fed VC-CSNPs and subsequently challenged with Vibrio harveyi. The results revealed several notable benefits in shrimp that received vitamin C-loaded nanoparticles:
- Improved Growth and Feed Efficiency: Shrimp not challenged with disease and fed VC-CSNPs showed a significant increase in body weight and feed efficiency. This suggests that vitamin C nanoparticles contribute to healthy growth.
- Enhanced Disease Resistance: Shrimp treated with VC-CSNPs exhibited significantly higher resistance to Vibrio harveyi infection. This indicates that these nanoparticles strengthen the shrimp’s immune system, which is essential for disease prevention.
- Enhanced Immunological Parameters: Shrimp that received the nanoparticles showed improvements in various immunological parameters, including phenoloxidase, transglutaminase, respiratory burst, total hemocyte counts, and disease resistance. These indicators highlight the crucial role of VC-CSNPs in improving immune health in whiteleg shrimp.
- Impact on Gene Expression: Significant improvements were detected in the expression of genes related to immunity, such as lectin, lysozyme, and cMnSOD, in shrimp groups treated with VC-CSNPs. This suggests that nanoparticles positively influence gene expression related to immune response.
The research clearly demonstrates that chitosan nanoparticles loaded with vitamin C have a positive impact on the health and disease resistance of whiteleg shrimp.
The researchers report that microencapsulation can regulate the release of food elements over time and in the right location.
These results suggest a promising path for the use of VC-CSNPs as a dietary supplement in aquaculture, offering benefits in both growth and disease resistance.
Nanotechnology offers an exciting perspective for the future of aquaculture, improving sustainability and the health of key aquatic species such as whiteleg shrimp.
The study was funded by the University Grant Commission (UGC) through a Kothari Postdoctoral Fellow.
Marine Biotechnology Laboratory
Department of Biotechnology, School of Life Sciences
Pondicherry 605014, Puducherry, India
Annamalai Asaikkutti, Karuppaiya Vimala, Natwar Jha, Periyakali Saravana Bhavan, Venkatesan Arul. 2023. Effect of dietary supplementation of vitamin C-loaded chitosan nanoparticles on growth, immune-physiological parameters, and resistance of white shrimp Litopenaeus vannamei to Vibrio harveyi challenge, Animal Feed Science and Technology, Volume 305, 2023, 115764, ISSN 0377-8401, https://doi.org/10.1016/j.anifeedsci.2023.115764.