Outputs of the National Workshop in Croatia, Ivica Sučec, DVM

FAO TCP/RER/3402 “Assistance to Western Balkan Countries for Improving Compliance to International Standards on Aquatic Animal Health”   National workshop, Zagreb, February 19, 2015

Under the project “Assistance to Western Balkan Countries for Improving Compliance to International Standards on Aquatic Animal Health”, it is also envisaged that each participating country organize national workshop.   Therefore, on February 19, national workshop was held in Zagreb, in order to: Present activities during FAO project in past two years Introduce farmers on new approach for disease control in Croatia Present results from antimicrobial resistance baseline study conducted in 2013/2014 Present future activities of farmers as regards health status of freshwater farms One day workshop was held in Coratian Economic Chamber, with presence of 31 participants in total.

Assistance to Western Balkan Countries for Improving Compliance to International Standards on Aquatic Animal Health, Sanin Tanković, DVM The purpose of the presentation was to explain background of TCP, background to TCP/RER/3206, TCP Regional Facility TCP/RER/3206, and finally TCP/RER/3402 Regional TCP

Antimicrobial resistance baseline study results in 2013/2014, Dražen Oraić, DVM In introductory part of presentation, antibiotics, their role and mechanism how they work when applied were described. Furthermore, WHO findings on possible resistance were described, as main problem if antibiotics will be used in future, with no strategy and control of famers and competent authority. Each year, around 25000 deaths are noted, in relation to ATB resistance. Aquaculture producers use ATBs mainly in order to increase production by preventing diseases. There are three typs of resistance: clinical, fenotyp and genetic. In Croatia, in 2013. baseline study on ATB resistance was launched, and continued in 2014 as ATB resistance programme. Following bacteria were examined for resistance: Yersinia ruckeri, Flavobacterium psychrophila, Vibrio anguillarum, Tenacibaculum maritimum. Samples were tested on five antimicrobials: Oksitetraciklin, Trimetoprim, Florfenikol, Flumekvine, Eritromicin. As result, resistance is detect for OTC, Trimetoprim and Flumekvine in Vibrio anguillarum and Tenacibaculum maritimum and for OTC and Trimetoprim in Yersinia ruckeri, Flavobacterium psychrophila. Results impose action plan for several sectors, human, veterinarian, etc..Goal is to lower the impact of ATB resistance in people by prudent use of ATB, by producing manuals for farmers, and continuos monitoring.

Overview of the most important diseases in Croatian freshwater aquaculture during last five years, Snježana Zrnčić, DVM Presentation entitled “Overview of the most important diseases in Croatian freshwater aquaculture during last five years” was intended to inform participant about occurrence of the most important listed and economically important diseases and about the diseases which may endangered national aquaculture industry. Although Croatia is implementing surveillance programme with regard to viral listed diseases according to national legislation based on the Council Directive 2006/88/EC there were two single outbreaks of both listed viral diseases on two different Croatian farms. In July 2013., high mortalities in rainbow fry were noticed. Affected fish showed exophtalmia, pale gills, distended abdominal wall with haemorrhages on the skin, in the eye, on the liver, pyloric caeca, swimbladder, intestine, in dorsal musculature and enlarged spleen.

VHS virus was isolated on cell cultures, identified by ELISA and confirmed by RT-PCR and by sequencing it was found that virus belongs to genotype Ia, subtype 2, grouped into subclade Pol II. In December 2013., samples from newly established rainbow trout were submitted to NRL as a part of routine monitoring programme. Affected fish showed exophthalmia, pale gills, hemorrhages on the skin, fat tissue, pyloric caeca, peritoneum and intestines, liver and in dorsal musculature. Cell culture examination resulted by virus isolation and identification was performed by ELISA, confirmed by RT-PCR and by sequencing results we concluded that IHNV isolate belongs to M group. In both cases we could not find out the source of infection. Later on viral diseases were spread to another farms so totally six farms are considered infected. Participants were informed about main symptoms diagnostic procedure for detection of Infectious pancreatic necrosis (IPN), Rainbow trout fry syndrome (RTFS), bacterial gill disease and Red mark syndrome in rainbow trout cultivation. They were also informed about diseases that my threaten carp production like listed disease Koi herpes virus disease (KHV) and other diseases like Spring viraemia of carp (SVC), Swim bladder inflammation (SBI) and carp erythrodermatitis CE).

Aquaculture strategy in Croatia, Emin Teskeredžić, DVM In this presentation, overview of main obstacles and future plans for Croatian Aquaculture were presented, beginning from drought in 2010., breakdown of supports from government, predators, high fees for water management and most recently, outbreaks of viral haemorrhagic septicaemia and infectious haematopoietic necrosis on trout farms. As conclusion, on behalf of trout producers association, it is agreed that eradication of trout diseases (VHS, IHN, IPN) is of utmost importance. Producers gave positive examples in other countries with eradication programmes, which were successful, and virus was eradicated (USA, Denmark).

Aquatic animal heatlh surveillance programmes in 2015, Ivica Sučec, DVM In this presentation, participants were informed about aquatic animal surveillance conducted on trout and carp farms registered in Croatia. Results were shown from 2009, and consisted surveillance data for VHS/IHN, IPN and Koi herpes virus disease in period from 2009 till 2014. In 2009. Surveillance program was launched in order to collect data from all trout farms in Croatia, in order to achieve disease free status for VHS/IHN. Results of surveillance were satisfactory till 2013. Since then, six outbreaks of VHS/IHN were noted, and epidemiological situation in Croatia is no longer favorable. As regards KHV, surveillance programme was also conducted on all farms with susceptible species, and in five years of targeted surveillance with negative results, conditions for disease free country were achieved. Due to fact that VHS/IHN virus is present in 6 farms in Croatia, sampling and investigation of wild population was conducted in December 2014. Results showed that in all susceptible species in open waters, virus was not found. Furthermore, presence of Onchorhyncus mykiss was much less than expected, and brown trout is known to be less susceptible to viral diseases such as VHS. Sampling of wild species was conducted on three rivers (Kupčina, Dretulja i Gacka).

Furthermore, farmers were introduced to plan for surveillance of aquatic diseases in 2015. It is envisaged that farmers themselves will have much bigger role in decision making for their surveillance programmes in 2015. VHS/IHN surveillance is envisaged for all trout farms which are already under surveillance, and for those that are infected, eradication programme is also envisaged. Furthermore, programmes for achieving additional guarantees, in order to be more competitive in EU market, and no to have any obstacles for free trade of live fish. One of such proposals is program for Spring viremia of carp. Forms for submission of application for this surveillance program, and for declarations of disease free status will be drafted and delivered to farmers. After filling in the form, application will be evaluated, and declaration and/or draft surveillance/eradication will be presented and sent to EC for approval.