The Effect of Low Salinity Water with Different Ionic Composition on the Growth and Survival of Litopenaeus vannamei (Boone, 1931) in Intensive Culture

Abstract

The effects of four different ionic composition low salinity water (T₁, T₂, T₃, and T₄), on growth and survival of Litopenaeus vannamei marine shrimp juveniles were investigated. Shrimp culture in seawater (T_m) was used as control treatment. The results indicated that there were no significant difference (P < 0.05) in growth, survival, production, and feed conversion ratio (FCR) of L. vannamei juveniles reared in the different treatments, but significant differences (P < 0.05) were observed between each of them when compared with seawater (T_m). After 84 days, culture shrimp grew from 0.02 to 7.58 g in T₁. The lowest growth rate was attained in T₃ (0.57 g/week), in which potassium and calcium ions concentrations were the lowest (0.58 and 28.00 mg/L, respectively). The recorded survival rate (76.35% to 79.55%) is considered well for the 84 days growout period, although it was 7.6% lower than that recorded in the control treatment. Although there were no significant differences (P < 0.05) in growth with respect to the ionic composition of the four treatments, there was a trend of increasing growth in relation with the ionic ratio found in the seawater (T_m). This aspect should be evaluated more closely in future research.

KEYWORDS:

• Low salinity
• ionic ratio
• well water
• growth
• L. vannamei

We would like to thank the Consejo Estatal de Ciencia y Tecnología de Sinaloa (CECYT-Sinaloa 2005) and the Instituto Politécnico Nacional (SIP-20050235) for providing funds for this research. The authors would like to extend thanks to the Aquapacific Hatchery for providing L. vannamei postlarvae.