Preliminary investigation onto the killing effect of kingfish (Seliola lalandi) serum and mucus against the monogenean parasites Benedenia seriolae and Zeuxapta seriolae
Leef, MJ and Lee, PS, Preliminary investigation onto the killing effect of kingfish (Seliola lalandi) serum and mucus against the monogenean parasites Benedenia seriolae and Zeuxapta seriolae, Aquaculture: An International Journal Devoted to Fundamental Aquatic Food Resources, (17) pp. 607-614. ISSN 0044-8486 (2009) [Refereed Article]
Abstract The survival of two economically important monogenean parasites, Benedenia
seriolae and Zeuxapta seriolae, exposed to either naż®ve or infected yellowtail kingfish
Seriola lalandi serum and mucus was observed over an 8-h period. Infection status of the
host had no effect on survival of monogeneans in either serum or mucus therefore data
were grouped according to each parasite. Serum exposure at the highest concentration of
1:5 did not have any effect on Z. seriolae, however, 50% killing activity against
B. seriolae was observed within 3 h at concentrations greater than 1:100. This killing
activity was completely abolished following heat treatment and inactivation of the serum.
Prior incubation of parasites with heat-treated serum for 2 h in order to potentially coat the
parasites with antibodies did not enhance the activity of fresh serum against either species.
Addition of 5 mM EDTA, but not 5 mM EGTA-Mg, inhibited the killing ability of fresh
serum against B. seriolae, suggesting that previously observed activity against this parasite
was most likely mediated via the alternative complement pathway. Cutaneous mucus was
not found to have any effect on B. seriolae or Z. seriolae survival. Overall these results
suggest that the blood-feeding gill parasite Z. seriolae is considerably more resistant to
host immune responses compared with skin- and mucus-dwelling B. seriolae.
Keywords Yellowtail kingfish Seriola lalandi Monogenean Innate immunity
Benedenia seriolae Zeuxapta seriolae Classical and alternative complement activity
Parasitic disease Aquaculture
M. J. Leef (&) P. S. Lee
National Institute of Water and Atmospheric Research Ltd., Bream Bay Aquaculture,
PO Box 147, Ruakaka, New Zealand