Comparative evaluation of the biofloc system versus the recirculation system with Macrobrachium amazonicum / Avaliação comparativa do sistema bioflocos versus o sistema de recirculação com Macrobrachium amazonicum

The aim of this study was to evaluate the efficiency of the biofloc system versus the recirculation system using the native Amazonian freshwater shrimp Macrobrachium amazonicum (Heller, 1862) as a cultivation organism. In this initial evaluation, the water quality parameters of each system were measured and the survival rate in the biofloc system showed similar values for M. amazonicum grown in a super-intensive recirculation system with averages values of 60%. The results indicated that both systems were within acceptable limits in terms of parameters (physical-chemical) and the survival rate of both systems showed similar values for M. amazonicum.

Incorporation of probiotic bacteria on larval culture of Macrobrachium amazonicum (Heller, 1862)

In this study, we evaluated the utilization of two probiotics incorporated into the water and in the diet in a larval culture system of Amazon River prawn. Autochthonous probiotic bacteria from the gut of wild juveniles of M. amazonicum juveniles and a commercial probiotic were tested and the following parameters were analyzed: survival, productivity, fresh weight, length, larval condition index (LCI) and larval stage index (LSI). The colonization of the larval gastrointestinal tract by probiotics took place when they were incorporated into diet, while probiotics in the water proved to be unsuccessful. The use of lactic acid bacteria had no significant effects (p>0.05) on survival, productivity, length, fresh weight, LSI and LCI, showing similar results in relation to the control group. However, we recommend the inclusion of probiotics into diet in larval culture of Amazon prawn since this method allowed bacterial gut colonization, which is important to evaluate the resistance to disease in further studies.

Elaboração de farinhas de Camarão da Amazônia (Macrobrachium amazonicum) e suas aplicações em sopas instantâneas

Os resíduos de camarão possuem alto valor nutricional, podendo ser transformados em farinhas para o consumo humano, com viabilidade de inclusão e enriquecimento de produtos alimentícios. O objetivo deste trabalho foi desenvolver sopa instântanea a base de farinhas de camarões, gerando uma alternativa para aproveitamento de resíduo do processamento. Foram elaboradas três diferentes farinhas de camarão da Amazônia (Macrobrachium amazonicum), sendo o tratamento 1= farinha do camarão da Amazônia inteiro (FCI), tratamento 2 = farinha do camarão da Amazônia inteiro limpo (FCL) e tratamento 3 = farinha do resíduo do camarão da Amazônia inteiro (FRC), que foram incluídas em sopas instantâneas, com posterior caracterização da composição centesimal e sensorial. As farinhas e as sopas estavam dentro dos padrões microbiológicos. A farinha de camarão limpo apresentou maior teor de proteína bruta (87,32%) e a farinha de resíduos de camarão os maiores teores de cinzas e carboidratos, 22,59% e 17,06%, respectivamente. Quanto à umidade e aos lipídeos totais, não houve diferenças significativas entre as farinhas elaboradas. A sopa instantânea com a FCL apresentou o maior teor de proteína (23,42%) e o menor teor de cinzas (5,75%). Mas, em relação a análise sensorial foi a sopa com inclusão de FRC que apresentou as melhores notas para os atributos aroma, impressão global e intenção de compra, enquanto para os demais não houve diferença significativa. Assim, os resíduos gerados no processamento do camarão podem ser utilizados para elaborar farinhas de elevado valor nutricional, para a inclusão em diversos produtos alimentícios comumente consumidos pela população, como sopas instantâneas.

Improving the Efficiency of Lambari Production and Diet Assimilation Using Integrated Aquaculture with Benthic Species

A single farmed fish species assimilates about 20% of the nutrients in the supplied diet. This study evaluated if the culture of complementary ecological-function species can recover nutrients dispersed into water and transform them into high-valued biomass. A completely randomized experiment was designed with three treatments and four replications of each production system: monoculture of lambari (Astyanax lacustris); integrated aquaculture of lambari and Amazon river prawn (Macrobrachium amazonicum); and integrated aquaculture of lambari, Amazon river prawn, and curimbatá (Prochilodus lineatus). Fingerlings of lambari (0.8 ± 0.8 g) were stocked in twelve earthen-ponds (0.015 ha) at the density of 50 fish m−2. Eight ponds were stocked with juveniles of Amazon river prawn (1.1 ± 0.2 g) at the density of 25 prawn m−2. Four of these eight ponds were stocked with curimbatá fingerlings (0.2 ± 0.1 g) at a density of 13 fish m−2. Only lambari was fed twice a day with an extruded commercial diet. The experiment lasted 60 days when lambari attained commercial size. The inclusion of prawn increased the total species yield from 1.8 to 2.4 t ha−1 cycle−1 and reduced the feed conversion ratio (FCR) from 2.5 to 1.8. The inclusion of prawn and curimbatá increased the total yield to 3.2 t ha−1 cycle−1 and reduced the FCR to 1.4. Therefore, the integrated culture of lambari, prawn, and curimbatá improves the use of space, water, feed, and benthic species to recover the large quantity of nutrients accumulated in the bottom of lambari pond production, converting them into high-nutritional and monetary-valued biomass.

Effects of ammonia and nitrite on food consumption of the Amazon River prawn Macrobrachium amazonicum (Heller, 1862) postlarvae

Experiments were carried out to study the effects of ammonia and nitrite on food consumption of Macrobrachium amazonicum postlarvae. Postlarvae (average weight of 0.0625 g) were exposed during 21 days to four concentrations of total ammonia (0, 1.05, 2.1 and 4.2 mg. NH3+NH4+ L-1) and four concentrations of nitrite (0, 0.075, 0.15 and 0.30 mg N-NO2- L-1). After the exposure period, six prawns per treatment were maintained individually in 250 mL experimental units to analyze the food consumption as a function of the amount of food offered and the leftovers during a 24 h period. The food consumption presented significant alterations for prawns exposed to all nitrite concentrations and at concentrations of twice the recommended safety level for total ammonia. According to the results obtained, high concentrations of total ammonia and nitrite affect the food consumption of M. amazonicum adversely, influencing the species performance in culture systems.