ABSTRACT
This study aims to investigate the use of pond apple (Annona glabra) compounds as a novel strategy to prevent and treat acute hepatopancreatic necrosis disease (AHPND) as well as to better understand the mechanism of health improvement in shrimp. The A. glabra leaf extracts were extracted using various solvents and examined for in vitro and in vivo activity against Vibrio parahaemolyticus strains. In comparison with ethanol and water extracts, methanol extract showed the strongest bactericidal effect (MBC/MIC ratio of 2.50 ± 1.00), with minimal inhibitory concentration (MIC) of 0.023 ± 0.012 mg ml-1 and minimum bactericidal concentration (MBC) of 0.065 ± 0.062 mg ml-1. White leg shrimp (P. vannamei, body weight 10.37 ± 0.27 g) fed A. glabra methanol extracts-containing diets (AMEDs) at 1 %, 1.5 %, and 2.0 % demonstrated no deleterious effects on survival and were significantly increased in length and weight after 30 days of feeding. The level of total haemocyte, hyaline haemocyte on day 15 and granulocyte on day 30 remarkably increased (p < 0.05) in shrimps fed AMEDs groups compared to those in the control group. The finding demonstrates that granulocyte was induced time dependently. In particular, the survival rate of V. parahaemolyticus challenged shrimps under medication with AMEDs at 1.5 % and 2.0 % was significantly higher (p < 0.05) than that of the control group. The decrease in bacterial load of Vibrio spp. and V. parahaemolyticus was obviously recorded in hepatopancreas shrimp given AMEDs 1.5 % and 2.0 % and may be linked to herb characteristics such as antibacterial activity, enhancing innate immunity, and its potential to maintain the integrity of hepatopancreatic tissue. Our findings suggest that A. glabra extract might be used as a health enhancer in commercial farmed shrimp.
