Determinación de la concentración letal de la saponina en el mejillón mytella strigata y su efecto en el camarón litopenaeus vannamei.

Abstract

This study sought to determine the median lethal concentration (LC50) of saponin in the mussel Mytella strigata and how this dose would affect the shrimp Litopenaeus vannamei. Quantitative experiments were carried out using 150 mussels (10 and 20 mm) and 90 shrimp (0.7 and 3 g), applying 5 treatments with different doses of saponin (0.4 - 0.6 - 0.8 - 1 - 1.2 ppm) with their respective control (0 ppm) in triplicate, during a period of 96 hours. The results were analyzed using "Regression and Probit Analysis" in SPSS to calculate the LC50. Mussels of both sizes showed an increase in mortality directly related to saponin concentration and exposure time. In the case of 10 ± 1 mm mussels, 100% mortality was observed within 72 h from a concentration of 1 ppm saponin, and similar results were found in the case of 20 ± 1 mussels. On the other hand, in L. vannamei weighing 0.7 g, doses of saponin at 1 and 1.2 ppm resulted in a significant increase in mortality in response to exposure time. In the case of 3 g shrimp, they showed no mortality at any of the saponin doses used. The results obtained show that the LC50 of saponin in mussels was 0.4 and 0.49 ppm for 10 and 20 mm organisms, respectively. When shrimp were subjected to the same doses of saponins, the 0.7 g organisms had an LC50 of 2.27 ppm. These results suggest that saponin is effective in controlling unwanted mussel populations, and that it is slightly toxic to 0.7 g shrimp, and non-toxic to 3 g shrimp. This supports its potential use in aquaculture, and especially in shrimp farming, without affecting cultivated species.