Differences in the
Susceptibility of American White Shrimp Larval Substages (Litopenaeus
vannamei) to Four Vibrio Species
G.
Aguirre-Guzmán, R. Vázquez-Juárez, F. Ascencio-2001
Journal of Invertebrate Pathology, 78(4):
215-219
Abstract:
The rapid expansion of commercial culture
of penaeid shrimp is threatened by Vibrio diseases affecting
survival and growth. These opportunistic microorganisms are considered part of the normal ecosystem of penaeid
shrimp and cause diseases only under conditions that
favor them over the host. Shrimp larvae show different susceptibility to these pathogenic agents. In the
present work, we report on a comparative study of the
susceptibility of all American white shrimp (Litopenaeus vannamei)
larval substages to four potentially pathogenic Vibrio species (V. harveyi, V. parahaemolyticus, V. alginolyticus,
and V. penaeicida). Strains of these bacterial
species were used to infect nauplii, protozoea I-III,
mysis I-III, and postlarvae 1 by immersion challenge
at 10 , 105, or 107 cfu mL-1
for 30 min. V. alginolyticus infection had no significant
effect on survival rate, compared to control, in all shrimp larvae and at all doses tested. Shrimp larvae
infected with V. alginolyticus showed a high survival
rate compared to other Vibrio species at the three
dose levels. V. penaeicida produced a significant mortality
effect (P < 0.01) in all shrimp substages and
only in postlarvae 1 at low infection dose (103 cfu mL-1).
V. harveyi and V. parahaemolyticus induced significant mortality rates (P < 0.01) only at high doses in shrimp larvae. In summary, shrimp larvae demonstrated
an age susceptibility that depends on the Vibrio species
and dose level.
(Unidad de Patología Marina, Centro de
Investigaciones Biológicas del Noroeste, 23090, La Paz, Baja California
Sur, Mexico, Fax: +52 (612) 1254710, e-mail of F. Ascencio : ascencio@cibnor.mx)