ATTI DEL XV CONVEGNO NAZIONALE SIPI Società Italiana di ...

Abstract Workshop
LEGISLATION AND HEALTH SITUATION IN CROATIAN AQUACULTURE
Snježana ZRNČIĆ, Dražen ORAIĆ
Croatian Veterinary Institute, Dept. of Pathology, Laboratory for Fish Diseases, Savska
143, 10000 Zagreb, Croatia
Croatia is with its south part the Mediterranean country while with its northern part it
belongs to the Central Europe. Aquaculture sector in Croatia is diverse and depends upon
natural conditions. Almost same quantities are produced in freshwater and marine
aquaculture. Warm water freshwater aquaculture is situated in the continental (northern)
part of the country and the major produced species are common carp (Cyprinus carpio),
grass carp (Ctenopharyngodon idella), silver carp (Aristychthys nobilis), bighead
(Hypophthaltmichthys molitrix), catfish (Silurus glanis), pike (Esox lucius) and pike perch
(Zander lucioperca) while salmonids‟ farms are in the mountain region cultivating rainbow
trout (Onchorhynchus mykiss) and brown trout (Salmo trutta m. fario). Along the Adriatic
coastline long 5800 km there are several farms of sea bream (Sparus aurata), sea bass
(Dicentrarchus labrax). Some quantities of fry for cultivation farmers are buying from 4
Croatian hatcheries while the rest is imported from other Mediterranean countries. On the
same farms small amounts of sharp snout sea bream (Diplodus puntazzo) and dentex
(Dentex dentex) are produced. The farming of all mentioned species until market size is
carrying out in cages of different shape and size. In the recent decade some tuna (Thunnus
thynnus) farms have been established. This type of aquaculture is based on the fattening
captured fish of different size, age and origin caught in Mediterranean Sea according to
ICCAT. Cultivation of molluscs species; oysters (Ostrea edulis) and mussels (Mytilus
galloprovincialis) has the longest tradition, from the Roman times. Overall annual
production in fresh water and in the sea is about 16.000 tons and the consumption of fish is
low, about 10 kg per capita. The major part of the production is being exported. Control of
fish viral diseases listed by EC/OIE is performed according to the “Decree on the measures
of animal health protection against infectious and parasite diseases” issued yearly by
Ministry of Agriculture, Fisheries and Rural Development. During the present year an
“Ordinance on animal health requirements for aquaculture animals and products thereof,
and on the prevention and control of certain diseases in aquatic animals" based on Council
Directive 2006/88/EC was been adopted. A field survey is carrying out to study the
occurrence and distribution of viruses causing diseases of major impact in salmonids,
cyprinid or marine fish farming, namely viral haemorrhagic septicaemia (VHS), infectious
haematopoietic necrosis (IHN) in salmonids, spring viraemia of carp (SVC) and koi herpes
virosis (KHV) in cyprinds and viral encephalopathy and retinopathy (VER) in sea bass.
The same regulation prescribes surveillance of molluscs diseases caused by Marteilia
refringens and Bonamia ostreae. This report derives from systematic clinical,
parasitological, pathoanatomical, histopathological, bacteriological and virological
monitoring of cultivated fish and shellfish on larger part of production during last several
years. Among pathological conditions recognised on our farms, some specific viruses like
infectious pancreatic necrocisis virus is present and there were an occurence of infecious
haematopoetic necrosis virus in carantine. Bacterial diseases are very often the cause of
mortalities in all kind of cultivated species. The most serious problems are caused by
bacteria from the genus Aeromonas, Vibrio, Flavobacterium, Tenacibaculum and
occasionally Photobacterium. Parasites represent frequently established causative
nosologic agents but the most serious problems are caused by those caused my
myxosporidiums. One of the very interesting problematic is pathology in tuna farming.
Until now there were several outbreaks on the tuna farms along the coast, but until now
there is no systematic approach to the study of the diseases and epizootiology of the some
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