Seasonal variation on the ectoparasitic communities of Nile tilapia cultured in three regions in southern Brazil

Abstract

A total of 240 Nile tilapia were examined between April 2007 and March 2008, gathered from three different fish farms, 20 fish in each fish farm, in the four seasons of the year. Fish ponds were located in Joinville, Blumenau and Ituporanga, Santa Catarina state, Brazil and each pond had a different culture system. Prevalence, mean intensity, mean abundance and mean relative dominance were compared among fish ponds and seasons. During this period, the water quality was kept in normal values. Piscinoodinium pillulare (Dinoflagellida) was the most dominant parasite followed by Trichodina magna e T. compacta (Ciliophora), Cichlydogyrus sclerosus, C halli, C. thurstonae, Scutogyrus longicornis (Monogenoidea), copepodids Lernaeidae gen. sp. The highest prevalence, mean intensity and mean abundance of ectoparasites were found on the body surface in fish from Joinville followed by Blumenau and Ituporanga. In the gills, the highest mean intensity and mean abundance were found in fish from Blumenau and Ituporanga in the winter. Piscinoodinium pillulare showed prevalence 100% during autumn in Blumenau and Ituporanga. In winter P. pillulare occurred in all study facilities. Fish from Joinville showed 100% prevalence of Monogenoidea during all seasons, as well as the highest mean intensity and abundance. The results showed that the majority of examined fish had higher infestations by protozoan during autumn and winter and higher infestations by metazoan have occurred in spring and summer.

Outbreak of Notozothecium bethae (Monogenea: Dactylogyridae) in Myleus schomburgkii (Actinopterygii: Characiformes) cultured in the Peruvian Amazon

“…However, monogeneans were detected during each sampling throughout the study period which is in accordance with previous studies that reported presence of monogeneans throughout all seasons (Rabago-Castro et al 2011;Jerônimo et al 2011).…”

“…The freshwater fish Myleus schomburgkii Jardine, 1841, is a rheophilic omnivorous species from the Family Serrasalmidae, popularly known in Peru as ''banda negra'' (English name = black band myleus) and widespread in the middle and lower Amazon River basin, Nanay River, upper Orinoco River basin in South America (Jégu 2003). This fish can grow up to 42 cm and reach 600 g, and it is considered as a potential species for the diversification of aquaculture production in the Peruvian Amazon (Garcia et al 2012).…”

Protozoan and myxozoan infections in wild gilthead seabream (Sparus aurata L.) from North Lake of Tunis, Tunisia

“…Many authors have determined the relationship between seasonal dynamics of trichodinids and water quality and reported that the maximum rate of infection was in winter and/or in spring (Abu El-Wafa 1988;Hassan 1999;Özer and Erdem 1999;Özer 2000, 2003Jerônimo et al 2011). Previous studies have reported that the seasonal prevalence and intensity of trichodinids can be affected by organic pollution such as the level of nitrite, nitrate and phosphate (Ogut and Palm 2005) and the deposition of pig manure (Jerônimo et al 2011). The fish examined in this study presented at higher infection, necrosis, oedema and hyperplasia of the gills.…”

Haematological and histopathological analysis in South American fish Piaractus mesopotamicus parasitized by monogenean (Dactylogyridae)

“…According to data of Ministry of Fisheries and Aquaculture (Brasil, 2010), in Brazil in 2010, an increase of 35% in the pacu production was observed compared to 2008. By the way, the aquaculture development implies in intensive production system, which can lead to water quality problems, inadequate feeding, and infectious and parasitic diseases that cause significant economic losses (Jerônimo et al, 2011).…”