IDENTIFICATION OF BORROWING WORMS AND BACTERIA ASSOCIATED WITH SHELL INJURIES ON RED ABALONE Haliotis rufescens CULTURED IN BAJA CALIFORNIA

The cultured of red abalone Haliotis rufescens represents an alternative for economic development in the state of Baja California due to its market demand and the collapse of natural populations that support the Mexican fisheries. Currently, in some areas of the state, abalone farms exist with varying degrees of success. Like in any other productive activity several factors exist that affect the efficiency of culture practices; one of them is the presence of borrowing worms. In order to identify the species of the borrowing worms and bacteria associated to shell injuries present in cultured red abalone in one aquaculture facility from Baja California, conventional and molecular techniques where used. The injuries were located in the spiral area on the outer surface of the shell, covering up to 7% of the total area.

The polychaete spionids found were identified as Boccardia proboscidea, (Figure 1) this organism has been associated with similar perforations on cultured abalone in South Africa. The bacteriological analysis, determined that most of the bacteria present in the areas surrounding the lesion belong to the genus Vibrio; the majority are considered to be part of the clade Splendidus, within this clade bacteria as Vibrio splendidus is able to cause secondary infections in soft tissue and strains in the matrix of the shell. We are facing a typical case of boring polychaete infestation. This event has reiterated the importance of implementing control measures and an adequate management in abalone farming.