Evaluation of CpG-Oligodeoxynucleotides as Immunostimulants and Protecting Agents Against Aeromonas hydrophila in Freshwater Lobster (Cherax quadricarinatus)

Abstract

MAS disease (Motyle Aeromonas hydrophila) is a prevalent bacterial infection that affects freshwater lobsters. This research aimed to evaluate the potential of CpG-ODN as an immunostimulant and protecting agent in Cherax quadricarinatus lobsters. The study was conducted at the Fish Health Laboratory, Pangkep State Polytechnic, Indonesia. The lobsters were divided into different groups and injected with three types of CpG-ODN (2133, 2006, 1668) or a control group using PBS. Parameters such as Total Hemocyte Count, Phagocytic Index, and Lysozyme Activity were measured at multiple time points, including before and after injection. CpG-ODN 2006 showed significant immunostimulant effects, as evidenced by a notable increase in total hemocyte count, phagocytic index, and lysozyme activity compared to the other CpG-ODN types. On the other hand, CpG-ODN 2133 exhibited potential as a protecting agent against Aeromonas hydrophila, as lobsters injected with this CpG-ODN demonstrated higher survival rates in the challenge test compared to the control group. These findings contribute to our understanding of immunostimulant strategies and protective mechanisms in freshwater lobsters. CpG-ODN, particularly CpG-ODN 2006, shows promise as an effective immunostimulant, while CpG-ODN 2133 exhibits potential as a protecting agent against A. hydrophila. Further exploration of CpG-ODN applications could lead to advancements in disease management in aquaculture.