ABSTRACT
With the aim to determine the prevalence and mean parasite intensity in Oncorhynchus mykiss, 120 specimens were analyzed between April and September 2018. The cavity analysis was done by visual inspection, scraping of mucus, and extraction of the branchial arches. In the evisceration process, the intestine, the liver, and the kidney were separated, while the musculature was analyzed using the "candling table" method. All the collected material was preserved in 10% buffered formaldehyde and sent to the Laboratory of Parasitology and Parasitic Diseases, of the Center for Agroveterinary Sciences (CAV) of the University of the State of Santa Catarina (UDESC) for making the slides and identifying the parasites. Parasites were detected only in the analysis of the scraping of body mucus. Only specimens of the genus Trichodina were identified, in 34 of the 120 fish analyzed, in two collections, resulting in a prevalence of 28.33%. In total, 144 specimens of Trichodina were observed. The overall mean intensity was of 4.24 parasites in each fish analyzed. Characteristic lesions of infection by protozoa were not identified. This is the first report of the occurrence of Trichodina spp. in O. mykiss bred in an intensive system in Brazil, with low rates of parasitic infection in the mountain region of Santa Catarina.(AU)
Subject(s)
Animals , Oligohymenophorea , Ciliophora Infections/veterinary , Oncorhynchus mykiss/parasitology , BrazilABSTRACT
ABSTRACT A helminthological examination was carried out on 14 specimens of Eucinostomus melanopterus (flagfin mojarra) and 19 Eugerres plumieri (striped mojarra), of which a total of 461 helminths were collected. As a result, and 12 taxa were registered (five species, five genus and tow family), as follows: four monogeneans, five digeneans (four adults, one metacercaria), one cestode (larva) and tow nematodes (larvae). The highest prevalence was for Neodiplectanum mexicanum (29 %) infecting E. melanopterus and Aristocleidus hastatus (37 %) infecting E. plumieri. Both hosts shared 50 % of recorded species, and none of the identified helminthes represents a zoonotic risk.
RESUMEN Se efectuó un examen helmintológico a 14 especímenes de Eucinostomus melanopterus (mojarra bandera) y 19 Eugerres plumieri (mojarra rayada), de los cuales se recolectaron un total de 461 helmintos. Se identificaron 12 taxones (cinco a nivel de especie, cinco a género y dos a familia) como sigue: cuatro monogéneos, cinco digéneos (cuatro adultos, una metacercaria), un céstodo (plerocercoide) y dos nemátodos (larvas). La prevalencia más alta fue para Neodiplectanum mexicanum (29 %) en E. melanopterus y Aristocleidus hastatus (37 %) en E. plumieri. Ambos hospederos comparten el 50 % de los taxones de parásitos. Ninguno de los helmintos representa un riesgo zoonótico.
ABSTRACT
Rhizoprionodon acutus (Rüppell) 1837, commonly known as ‘Milk shark’ is the frequently available elasmobranch from the Nellore (14.43°N 79.97°E.) coast off Bay of Bengal. A total of 152 R. acutus were collected from this coast during January, 2014- December, 2015, of which 89 hosts were infected with one or more parasites. A total of eleven species were collected, comprising of 6 cestodes, 2 nematodes, 1 Monogenean, 1 copepod and 1 isopod. Various ecological parameters such as prevalence, mean intensity, mean abundance and index of infection were calculated to determine the monthly population dynamics and the seasonal dynamics of the parasites in R. acutus. The study was carried out for both overall and groupwise parasitization. Endoparasitic infection predominated the ectoparasitic infection in the host. The study reveals the role of the temperature and season in the recruitment of parasite fauna in the hosts. The present study would be a great contribution to the knowledge of the metazoan parasite fauna of elasmobranch fishes to the future helminthologists from this Nellore Coast, Bay of Bengal.