Some sporcted fish was minced up in an Eppendorf tube using a peston and incubated with sterile sea water in order to disrupt the tissues and release spores from it. Finally, a pellet consisting predominantly of spores was collected and left to settle for 30 min onto poly-l-lysine coated slides and coverslips. Kidney tissue from one heavily infeal times. griseus) were obtained following the guidelines of Arthur and Lom (1989) and Sitjà-Bobadilla and Álvarez-Pellitero (1994). Measurements (n = 15 spores per fish, 3 L. Spores were measured on digital images using ImageJ v.1♴4p (Wayne Rasband, ) calibrated against a digital image of a graticule. Fresh kidney smears were observed under the light microscope at ×400 to ×1000 magnification. Fish were weighed, measured and necropsied. Thereafter, blood was taken from the caudal vein, using a sterile syringe, and 4 ?l of blood were collected in 100% ethanol. All specimens were maintained in the facilities for a maximum of 48 h before they were euthanised by an overdosis of MS222. Parasitological Study – Sampling Procedures and Morphological Detailsįish were transported live to the aquaculture facilities of Mote Aquaculture Research Park (MAP) in large, aerated containers and were transferred to an isolated holding tank on site. Thereby, the relation between age and TL was in accordance with the results from other studies ( Burton, 2001, Fischer et al., 2005 and Jones et al., 2010). On thin sections of otoliths, annual growth zones (annuli) were examined and the fish were ascribed to three year-based age classes: age-0 (n = 12 total length (TL) 7.5–10.5 cm), age-1 (n = 10 TL 20.6–25.2 cm) and age-2 (n = 5 TL 23.2–34.0 cm). griseus were captured for parasitological study.
Seine nets were used and some fish were caught by line fishing from the shore. The capture areas were characterised by sandy or muddy sediment, sometimes covered with sea grass, and a depth of 1–10 m. Fishing was conducted in shallow areas between the keys and the mainland, and in the canals connecting this area with the Gulf.
In November and December 2012 fish were caught at the Southeast coast of the Gulf, in Florida, between Anna Maria Island in the north (27☂6?36.15?N 82☄1?36.09?W) and New Pass in the south (27☁9?37.59?N 82☃5?14.06?W). griseus were obtained within the framework of fishery-independent surveys of fish communities occupying mangrove shorelines and creeks in the Gulf of Mexico. griseus, we aimed to characterise this species morphologically and molecularly, determine its prevalence and intensity of infection in different age classes of fish, describe the pathological changes it causes and determine whether it can be related to mortalities. In order to better understand the influence this specific myxozoan has on its host L. Myxozoans are microparasites belonging to the Cnidaria (Holland et al., 2011), and several species have been related to pathological changes and mortalities in wild and cultured fish species around the globe. During fishing efforts conducted by Mote Marine Laboratory and aiming at fish population studies along the mangrove shores of the Eastern Gulf of Mexico, it was noted that juvenile mangrove snapper caught by seine nets and subsequently released, sometimes failed to recover from the stress of capture.ĭuring a parasitological study of moribund mangrove snapper after their transport to the laboratory we detected macroscopic changes in their kidneys and large numbers of myxozoan spores in squash preparations. Increasing mortality and decreasing size-at-age along a temperature gradient from northwest to southwest Florida has also been reported (Allman, cited by Gold et al., 2009). 2 million lbs of grey snapper landed between 20 (NMFS, 2012).Īult et al., 2002 and Ault et al., 2005 reported that the spawning potential ratio (SPR) of mangrove snapper in the Florida Keys coral-reef system was below that of a healthy stock, indicating overfishing. griseus is a target species for commercial and recreational fisheries and the largest number of animals is being caught along the Gulf coast of Florida, with approx. The grey snapper Lutjanus griseus (L.), commonly also known as mangrove snapper, is a medium-sized snapper species which is restricted to the Western Atlantic, with its centre of distribution in the Gulf of Mexico and the Caribbean Sea ( Robins et al., 1986 and Allman and Grimes, 2002).
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