34 SEPTEMBER 2017 • WORLD AQUACULTURE • WWW.WAS.ORG Universities and research centres in Brazil have worked with marine finfish for decades but it was only in 2013 that Brazil started to produce an incipient volume of cobia, mostly in the southeast region. This species has shown promising results, reaching 4.5 kg in a year and up to 15 kg in two years in nearshore cages (Rombenso et al. 2014). Cobia production started at 25 t, passing to 110 t in 2014/2015 and lately producing around the same amount as the previous year (Rombenso et al. 2016, Rombenso in press). Other culture systems are being investigated, such as RAS in the south and pond culture in the northeast. With the current economic crisis, the number of producers and people interested in cobia production has grown lately due to the elevated market demand and high selling price of the whole fresh fish (US$ 13-17/kg) (Palmer et al. 2015). There is a considerable supply shortage of fresh marine fish and all farmed fish is sold, sometimes even during the production cycle. Despite the promising scenario, Brazil faces several bottlenecks on further expansion of marine finfish production, such as cobia aquaculture: (1) Existing aquafeed formulations are deemed inadequate, unaffordable, or both, (2) Disease incidence is mostly related to poor farm management, (3) The availability, frequency, quality and price of cobia fingerlings, (4) The lack of a breeding program and poor monitoring of genetic variability of cultured fish, (5) Poor communication among research, extension and production sectors (Rombenso and Trushenski 2016, Cavalli et al. in press). Seaweed Farming Seaweed farming in Brazil is still under development. Despite several trials from universities, international institutions and private companies over the years, there are only a few artisanal farms along the northeast coast (Ceara, Rio Grande do Norte and Paraiba states), small-scale commercial and experimental farms in the southeast and south (Rio de Janeiro and São Paulo, and Santa Catarina states, respectively), even with a high dependence on imports (Hayashi et al. 2014, Reis et al. 2016). and low feed conversion, which translates into short culture cycles and effective biomass production in aquaculture. Nonetheless, when compared to shrimp, fish and other molluscs, octopus culture is still at the beginning. At present, there is no large-scale culture anywhere in the world, only small industrial grow-out production of O. vulgaris sub-adults in Spain (Galicia) and experimental culture of O. maya in Yucatán, Mexico (Rosas et al. 2014). These two species are the most studied and are thus considered the main candidates and biological models for culture (Vidal et al. 2014). Octopus vulgaris can reach market weight (~ 3 kg) from an initial weight of 700 g in only 3-4 months during grow-out in cages at temperatures between 12-19 C (Rama-Villar et al. 1997). Growth rates obtained are quite impressive and range from 0.5-1 kg per individual per month (Vidal et al. 2014). The main obstacle to mass production is the voracious appetite and highly selective feeding habits of octopuses. As carnivores, they utilize protein very efficiently, with assimilation rates of up to 96 percent (Lee 1994). This is particularly true for early life stages, which require live food of high nutritional quality. Because of their high metabolism, octopus hatchlings can starve quickly if their nutritional requirements are not met, resulting in high mortality rates during larviculture. Thus, nutrition during larviculture and grow-out impose some limitations to mass culture of octopuses. This underscores the need for either a reliable live-food supply or the development of costeffective formulated feeds. A focus on nutritional requirements will play a vital role improving culture conditions and assessing production potential in the near future. Marine Finfish Production Brazil has an extensive coastline and considerable biodiversity, characteristics that enable the production of many marine finfish species in a variety of culture systems. Sometimes these many options make development of an activity challenging, which is the case for marine finfish farming in Brazil. There are more than 15 candidate species for aquaculture, ranging from omnivorous to carnivorous and from temperate to warmwater, including yellowtail Seriola spp., flounder Paralychtys orbignianus, grouper Epinephelus marginatus, mullet Mugil spp., pompano Trachinotus marginatus, jacks Caranx spp., and cobia Rachycentron canadum. Cobia Rachycentron canadum juveniles in a cage off the coast of São Paulo state. Photo: Pål Myhre. Larviculture of cobia Rachycentron canadum at a marine hatchery on the coast of São Paulo state. Photo: Pål Myhre.
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