Determining the Effect of Major Histocompatibility Genotype on Parasite Load of Common Snook

Parasites cause commercial losses for aquaculture and fisheries industries; can represent a threat to human health, and in wild fish, impact population structure by affecting reproductive fitness. Parasites rob the host of energy otherwise used for reproduction which may lead to fewer or smaller eggs produced, decreased egg quality, or lengthen the time between spawning events. The Major Histocompatibility (MH) genes are critical for recognition of self and non-self (pathogen derived) peptides, and therefore vital to an adaptive immune response to viral, parasite, and bacterial infections in wild and captive fish. This project will investigate the effect of MH genotype variability on parasite load of common snook, Centropomus undecimalis, and relate parasite infection to fecundity. The common snook is a popular gamefish in Florida, providing the state with millions of dollars each year in fishing revenue. To date 10 female snook have been examined for parasites, batch fecundity, and have been genotyped. Our hypothesis is that higher genetic variation of MH alleles will result in a lower parasite load and higher batch fecundity. To the best of the author’s knowledge, this will be the first study to test the relationship of MH gene variability on fitness of bony fish. This research is significant for not only for fisheries management, but also for the progression of our understanding of the role of disease in wild populations of fish.