Does the heterotrophic system influence the cellular immune response of Litopenaeus vannamei shrimp? In vitro phagocytosis indices and superoxide anion production comparisons.

Aquaculture production has increased in the last decades, with crustacean production contributing with 9.8% of the total production. However, fisheries and aquaculture sectors present several challenges, such as fish stocks fished beyond biological sustainability, animal diseases, biosecurity, and environmental impact. It is important to improve shrimp production with healthy animals, avoiding environmental impacts, e.g. with the use of heterotrophic rearing system. It is known that the heterotrophic system can stimulate the activation of immune genes, but how it affects the shrimp immune system is unknown. To assess if a heterotrophic system influences the cellular immune response in shrimp, Litopenaeus vannamei shrimp were reared in heterotrophic and clear water systems. Cellular immune response parameters such as total and differential hemocyte counts, phagocytosis indices and the production of the superoxide anion were evaluated after 60, 120 and 180 days. After 60 days, total haemocyte counts were higher in shrimps reared in the clear water system, while after 120 days it was higher in shrimps reared in the heterotrophic system. No significant difference was observed after 180 days. Hyaline, granular and semi-granular cells showed similar behavior, peaking after 120 days in the heterotrophic system. By the 60th day, phagocytic capacity was higher in the heterotrophic system, while no differences were found for the 120th and 180th day. No differences were detected concerning the phagocytic index or superoxide anion production. The heterotrophic system can affect total and differential shrimp haemocyte counts and phagocytic capacity, depending on the period of time they were maintained in this system. However, the phagocytic index and superoxide anion production are not affected by the heterotrophic system at the time points evaluated herein.

Evaluation of different sources of carbohydrates for the biofloc system and the growth of white shrimp / Avaliação de diferentes fontes de carboidratos para o sistema de bioflocos e crescimento do camarão branco

This study was aimed to evaluate the brewery wastes and other sources of carbohydrates for the biofloc system and different densities for the growth of white shrimp, Litopenaeus vannamei (initial weight of 0.35 ± 0.05g). The experiment was performed during 55 days, using 6 treatments, each one with 3 repetitions, using two stocking densities (300 and 500 shrimp m-2) and three substrates (residue brewery, sugar cane molasses and manioc flour). The abiotic parameters were monitored daily and biometrics occurred weekly for performance evaluation. The physicochemical parameters of water were found suitable for the species, however the nitrogen compounds reached low levels, but the indexes were satisfactory, with average survival, weight gain and final body weight between 74-82; 3.5- 5.0 and 4.2-5.7, respectively. It was found that treatment with the brewery residue presented superior zootechnical parameters and also further microbial flakes formation. Treatments with lower densities have had better indexes. The results demonstrate that the productivity of flakes in the different treatments is effective as a food supplement for growing L. vannamei and for water quality, and that between the substrates, the residue brewery proves to be excellent organic compound for the biofloc formation.(AU)

O trabalho teve como objetivo avaliar o resíduo de cervejaria e outras diferentes fontes de carboidratos para o sistema de bioflocos e diferentes densidades para o crescimento do camarão branco, Litopenaeus vannamei (peso inicial de 0,35 ± 0,05g). O experimento foi realizado durante o período de 55 dias, utilizando 6 tratamentos com 3 repetições cada, com duas densidades de estocagem (300 e 500 camarões m-2) e três substratos (resíduo de cervejaria, melaço de cana e farinha de mandioca). Os parâmetros abióticos foram monitorados diariamente e as biometrias ocorreram semanalmente, para a avaliação do desempenho. Os parâmetros físico-químicos da água encontraram-se adequados para a espécie, entretanto os compostos nitrogenados alcançaram níveis pouco elevados, porém os índices zootécnicos foram satisfatórios, apresentando médias de sobrevivência, ganho de peso e peso final entre 74-82%; 3,5-5,0g e 4,2-5,7g, respectivamente. Verificou-se que tratamentos com o resíduo de cervejaria apresentaram parâmetros zootécnicos superiores e também, maior formação de flocos microbianos. Os tratamentos com menores densidades apresentaram melhores índices zootécnicos. Os resultados demonstraram que a produtividade dos flocos nos diferentes tratamentos é eficiente como complemento alimentar para o crescimento de L. vannamei e para a qualidade da água, e que entre os substratos, o resíduo de cervejaria revela-se como excelente composto orgânico para a formação do bioflocos.(AU)

Evaluation of different sources of carbohydrates for the biofloc system and the growth of white shrimp / Avaliação de diferentes fontes de carboidratos para o sistema de bioflocos e crescimento do camarão branco

This study was aimed to evaluate the brewery wastes and other sources of carbohydrates for the biofloc system and different densities for the growth of white shrimp, Litopenaeus vannamei (initial weight of 0.35 ± 0.05g). The experiment was performed during 55 days, using 6 treatments, each one with 3 repetitions, using two stocking densities (300 and 500 shrimp m-2) and three substrates (residue brewery, sugar cane molasses and manioc flour). The abiotic parameters were monitored daily and biometrics occurred weekly for performance evaluation. The physicochemical parameters of water were found suitable for the species, however the nitrogen compounds reached low levels, but the indexes were satisfactory, with average survival, weight gain and final body weight between 74-82; 3.5- 5.0 and 4.2-5.7, respectively. It was found that treatment with the brewery residue presented superior zootechnical parameters and also further microbial flakes formation. Treatments with lower densities have had better indexes. The results demonstrate that the productivity of flakes in the different treatments is effective as a food supplement for growing L. vannamei and for water quality, and that between the substrates, the residue brewery proves to be excellent organic compound for the biofloc formation.

O trabalho teve como objetivo avaliar o resíduo de cervejaria e outras diferentes fontes de carboidratos para o sistema de bioflocos e diferentes densidades para o crescimento do camarão branco, Litopenaeus vannamei (peso inicial de 0,35 ± 0,05g). O experimento foi realizado durante o período de 55 dias, utilizando 6 tratamentos com 3 repetições cada, com duas densidades de estocagem (300 e 500 camarões m-2) e três substratos (resíduo de cervejaria, melaço de cana e farinha de mandioca). Os parâmetros abióticos foram monitorados diariamente e as biometrias ocorreram semanalmente, para a avaliação do desempenho. Os parâmetros físico-químicos da água encontraram-se adequados para a espécie, entretanto os compostos nitrogenados alcançaram níveis pouco elevados, porém os índices zootécnicos foram satisfatórios, apresentando médias de sobrevivência, ganho de peso e peso final entre 74-82%; 3,5-5,0g e 4,2-5,7g, respectivamente. Verificou-se que tratamentos com o resíduo de cervejaria apresentaram parâmetros zootécnicos superiores e também, maior formação de flocos microbianos. Os tratamentos com menores densidades apresentaram melhores índices zootécnicos. Os resultados demonstraram que a produtividade dos flocos nos diferentes tratamentos é eficiente como complemento alimentar para o crescimento de L. vannamei e para a qualidade da água, e que entre os substratos, o resíduo de cervejaria revela-se como excelente composto orgânico para a formação do bioflocos.