WWW.WAS.ORG • WORLD AQUACULTURE • DECEMBER 2012 47 2008, the CARPIOGARDA project was started, funded by the Autonomous Province of Trento. The project aims to define rearing protocols to produce hatchery strains used for rehabilitation, assess the status of spawning areas, and detect the best reintroduction techniques for the species. Rearing Trials A fish quarantine facility was specifically created near Lake Garda to evaluate the sanitary state of wild specimens regarding Viral Hemorrhagic Septicemia (VHS) and Infectious Hematopoietic Necrosis (IHN), following European animal health laws (European Parliament and the Council of the European Union 2006). Although there are similarities between carpione and other salmonids, specific hatching and rearing temperatures and artificial diets were evaluated in the quarantine facility. Rearing tests started from artificial breeding of wild specimens caught in 2006. Previous attempts to catch spawners in the lake were not successful. A lightdark cycle for spawners was tested in a modular production system called ZEFiRe — an acronym for Innovative Zero Energy Fish Farming Research. The ZEFiRe is an energy efficient, modular system for aquaculture that aims to improve energy efficiency, use renewable energy, and have low environmental impact. Water in the system can be reused repeatedly after a treatment process that uses bioremediation and phytoremediation techniques (Fig. 3). A prototype system was constructed to raise fish for commercial purposes. Carpione were reared in the ZEFiRe module in tanks where water temperature and light were set, simulating daily and seasonal natural variations of temperature and light in Lake Garda. (CONTINUED ON PAGE 46) FIGURE 2, ABOVE. Commercial catch of wild carpione in Lake Garda, Italy. FIGURE 3, BELOW. The ZEFiRe module. Environmental factors were monitored and simulated using a multi-parameter smart probe with remote sensing technology. Improvements of adult feeding and rearing conditions led to a high production of eggs and juveniles. Hatching rates were greater than 60 percent, compared to early artificial breeding (30 percent). There were problems similar to the reproductive disorder in salmon called the M74 syndrome. In carpione, the syndrome was manifest as offspring mortality during the yolk-sac fry phase, but mortality has been reduced by adding dietary supplements. For carpione held in captivity, anticipated sexual maturity was 1618 months for males and 24 months for females. Fish reared in captivity can spawn twice per year. This is undoubtedly an exceptional occurrence when compared to wild specimens, representing a peculiarity in the reproductive biology of salmonids. On the other hand, gregarious behavior has also been observed also in rearing tanks, where fish tend to move in shoals. Reared carpione are susceptible to some common bacterial diseases, such as furunculosis (Aeromonas salmonicida, Aeromonas hydrophila) and flavobacteriosis (cold water disease, Flavobacterium psychrophilum); water mold infections, such as Saprolegnia spp.; and parasites (Icthyobodo necator, Gyrodactylus spp.). Preliminary results of experimental infection of carpione revealed high resistance to VHS, while tests for sensitivity to IHN and Infectious Pancreatic necrosis (IPN) will be conducted in the near future.
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