Efecto de probiótico a base de Bacillus sp., Enterococcus sp., Pediococcus sp. y Lactobacillus sp. en la sobrevivencia y crecimiento larval de Litopenaeus vannamei en la Estación de Maricultura Los Cóbanos, Sonsonate

Abstract

The study was focused on the effect of a probiotic product based in four nonpathogenic bacteria (Bacillus spp., Enterococcus spp., Pediococcus spp. and LactoBacillus spp.) with Litopenaeus vannamei nauplii on Estación de Maricultura Los Cóbanos with 3.6 million from parent stocks from the same hatchery laboratory. The usual management given to the larvae in the Estación was compared with a treatment with probiotic; these larvae were grown from Nauplius till Postlarvae III in approximately 18 days. Student’s t distribution for different and equal samples was used, valuating 2 treatments: where T0 was the control treatment and T1, the alternative treatment adding probiotic. Each treatment had 2 physic repetitions and 16 to 36 time repetitions in the experiment. During the cycle, the larvae were influenced by non-controllable factors such as the lack of micro-algae and none water exchange for a period of days because mechanical breakdown of the bomb used in the Estación. These events had a significant effect on the survival rate, though the probiotic treatment shown better survival rates (S ≤ 12%) than the control treatment. The bacterial analysis of the water had the absence of pathogens, the only isolated bacteria was Escherichia coli with <1.1 NMP/100ML, which is in the allowed range according to the Norma Salvadoreña Obligatoria 2009. Even though, the total aerobic mesophilous bacteria recount on the probiotic treatment was low compared to the control treatment, which had too many for counting. In the PCR analysis, T1R2 was positive to IHHNV. The costpayoff relation of the probiotic treatment larvae showed better neat earning with $749.22, exceeding the control treatment