15 JUNE 1999
G. Alcaraz, X. Chiappa-Carrara, V. Espinoza, C. Vanegas-1999
Journal of the World Aquaculture Society, 30(1): 90-97 (from Current Contents)
Abstract:
Penaeus setiferus postlarvae were exposed to acute levels of ammonia, nitrite, and to a mixture of both by a short-term static method. The 24-h, 48-h and 72-h LC50 values for un-ionized ammonia were 1.49, 1.21 and 1.12 mg/L NH3-N (un-ionized ammonia as nitrogen), and 11.55, 9.38 and 8.69 mg/L ammonia-N (un-ionized plus ionized ammonia as nitrogen). The 24-h, 48-h and 72-h LC50 values for nitrite were 268.06, 248.84 and 167.33 mg/L nitrite-N (nitrite as nitrogen). Nitrite was much less toxic than ammonia. The joint effect of ammonia and nitrite on the postlarvae was synergistic at 48-h exposure and antagonistic after 72 h. Postlarvae of P. setiferus may be considered as organisms sensitive to ammonia and nitrite.
(Univ Nebraska, Sch Biol Sci, Lincoln, NE 68588, USA)