Parasitic infections in pirarucu fry, Arapaima gigas Schinz, 1822 drzane u poluintenzivnim farmama u sredisnjoj Amazoni u Brazilu

Studies regarding parasite fauna in farmed fish are of great relevance to the knowledge of the parasites species, allowing interference in their proliferation in order to avoid epizooties and consequently, economical losses. This study was designed to investigate the prevalence and intensity of parasites in fry Arapaima gigas maintained in ponds of a semi-intensive fish farm in Amazonas State, Brazil. On necropsy, 96.0% of A. gigas were found parasitized by Dawestrema cyclooncistrioides, Dawestrema cyclooncistrium (Monogenoidea), Trichodina sp., Ichthyobodo sp. (Protozoa), Camallanus tridenxatus, Terranova serrato, Goezia spinulosa (Nematoda) and Argulidae. However, D. cycloancistrium, D. cycloancistrioides and Trichodina fariai were the parasites of greatest intensity This study is the first to report parasitic infections in farmed A. gigas and the results indicated a high rate of infection that might lead to important changes in the health of the hosts. Key words: Amazon, Arapaima gigas, culture, infections, parasites Vet. arhiv 79, 499-507, 2009. Istrazivanje parazitske faune na farmama riba od velikoga je znacenja za nove spoznaje o parazitskim vrstama jer omogueuje upletanje u njihovo razmnozavanje s ciljem sprjecavanja pojave epizootija i smanjenja posljedicnih gospodarskih steta. Ovo istrazivanje poduzeto je u svrhu odredivanja prevalencije i intenziteta parazita u mladi vrste Arapaima gigas drzane na poluintenzivnim jezerskim farmama u drzavi Amazona u Brazilu. Pri razudbi je ustanovljeno da je 96,0% A. gigas bilo pozitivno na parazite Duwestrema cycloancistrioides, Duwestrema cycloancistrium (Monogenoidea), Trichodina sp., Ichthyobodo sp. (Protozoa), Camallanus tridenxatus, Terranova serrata, Goezia spinulosa (Nematoda) i Argulidae. Ipak, najcesoe dokazane vrste parazita bile su D. cycloancistrium, D. cycloancistrioides i Trichodina fariai. U istrazivanju se prvi put izvjeseuje o parazitima u farmski drzane A. gigas, a rezultati govore o visokoj stopi invadiranosti sto moze dovesti do znatnih poremeeaja zdravlja domaeina. Kljucne rijeci: Amazona, Arapaima gigas, kultura, paraziti Vet. arhiv 79, 499-507, 2009.