Efecto de los ácidos orgánicos en la carga bacteriana de vibrios spp. en el camarón blanco (litopenaeus vannamei).

Abstract

The technological advancements that the aquaculture industry presents today are a significant advantage, as these advances have led to a substantial improvement in this sector. However, as production intensifies, the carrying capacity of the pond increases, which also brings a greater risk of environmental disturbances in the aquatic environment. In the worst-case scenario, it can lead to the presence of pathogenic microorganisms, which can propagate in the crops, causing animals to become sick or die. One of the commonly employed strategies is antibiotics; however, their improper management has caused these pathogenic microorganisms to develop resistance to them. This study was conducted to evaluate the antimicrobial properties of commercial organic acid blends on Gram-negative bacterial colonies present in the hepatopancreas of white shrimp. For the development of this assay, three treatments with commercial organic acids (T1: AO1, T2: AO2, T3: AO3) and one control treatment without additives were tested, with three replicates for each. Sixty Litopenaeus vannamei specimens were used, which were fed twice daily according to their body weight, and evenly distributed in each of the containers with a constant aeration system. To maintain water quality in each of the experimental units, water changes were performed, and bacteria were added to control toxic metabolites. At the end of the assay, microbiological analyses were conducted to determine the number of Gram-negative bacteria (UFC/ml) in the specimens. The results obtained were statistically analyzed with one-way ANOVA, determining that there are significant differences between the treatments (T1, T2, T3) and the control (p <0.05), with T2 being the most effective in reducing bacterial load in the shrimp. Furthermore, the results of the in vitro analysis using the antibiogram showed varying sensitivity in terms of the inhibition zone, with T1 (10 mm) and T3 (12 mm), while no inhibition zones were observed in T2. Finally, the predominance of specific vibrios was determined, with V. alginolyticus and V. parahaemolyticus being displaced from the organism when using T1 and T2 compared to the control treatment. In conclusion, the use of commercial organic acid blends inhibits the growth of Gram-negative bacteria, increases the survival rate in shrimp, and becomes an alternative to reduce the use of antibiotics in aquaculture.