ABSTRACT This study aimed to evaluate 1) the in vitro effect of organic salts on the growth of the probiotic Lactobacillus plantarum and then 2) the combined use of a probiotic with organic salts on the in vitro inhibition of V. alginolyticus, A. hydrophila, E. coli, P. aeruginosa, and S. agalactiae. In vitro tests were performed with eight different organic salts, including butyrate, propionate, succinate, citrate, formate, fumarate, glutamate, and acetate, at two pH values (6.2 and 7.1) to determine their effect on the growth kinetics of L. plantarum. In addition, each organic salt was tested alone and in combination with L. plantarum to evaluate the inhibitory effect against the pathogenic bacteria noted above in either condition. Sodium citrate and formate inhibited the growth of L. plantarum, but sodium glutamate, succinate and fumarate stimulated it. Sodium propionate, butyrate, and acetate did not affect probiotic growth at all. Inhibition against all pathogens was significantly higher in the presence of the probiotic and lower pH. Comparing all organic salts at the two pH values, butyrate, acetate, and propionate exhibited more inhibition against V. alginolyticus than the others, while propionate had higher inhibition against A. hydrophila, E. coli, P. aeruginosa, and fumarate successfully inhibited S. agalactiae. Based on these results, it can be concluded that organic salts showed better in vitro inhibition against the aquaculture pathogenic bacteria tested when combined with the probiotic L. plantarum.

ABSTRACT A life-cycle assessment was conducted during semi-intensive and super-intensive commercial cultivation of marine shrimp from December 2011 to June 2012, considering all phases from the preparation of the nursery to harvesting of the shrimp, to determine the carbon footprints of each process. Inputs and outputs associated to the production of 1 kg of shrimp were evaluated using the CML-1A baseline method, V3.01 EU25, with Software SimaPro® 8.0.2, to identify the factors of impact that are most relevant to the category global warming, measured in kg of CO2 eq. The grow-out phase contributed the most to the final results in super-intensive culture, which had a higher carbon footprint, 47.9967 kg of CO2 eq., which was 1.0042 kg of CO2 eq. in the semi-intensive culture. The most important impacting factor is the use of electrical energy, which is required to maintain dissolved oxygen and the biofloc particles in suspension in the super-intensive culture and for movement of large volumes of water in the semi-intensive system.

ABSTRACT The objective of this study was to evaluate the effect of different stocking densities and the presence/absence of two artificial substrates on water quality and production rates of marine shrimp in a biofloc shrimp nursery culture. Two experiments were performed: different stocking densities with mosquito netting substrate and the presence/absence of polyester-type substrate. The first experiment lasted 38 days, and shrimp at an initial weight of 0.013±0.010 g were stocked in 24 tanks. The second experiment lasted 35 days, and shrimp at an initial weight of 0.037±0.002 g were stocked in six tanks. Weekly biometric measurements were performed to adjust the amount of feed. Suspended solids were higher at a density of 6000 PL m−3 and mosquito netting substrate. Final weight and specific growth rate were higher in treatments with mosquito netting substrate. However, survival was significantly lower with this substrate. Yield was significantly higher at a density of 6000 PL m−3. Polyester-type substrate had no significant effect on production rates or variables of water quality. However, this substrate could reduce the production of sludge. The results indicate that it is possible to culture shrimp in nursery stage up to 6000 PL m−3 in a biofloc system.

RESUMO. O presente trabalho avaliou os parâmetros imunológicos e a resistência contra o Vibrio sp. (CPQBA 378-12 DRM01) de camarões marinhos Litopenaeus vannamei alimentados com diferentes níveis de concentrado proteico de soja em substituição à farinha de peixe e cultivados em sistema de bioflocos. Foram formuladas quatro dietas com 0, 33, 66 e 100 % de concentrado proteico de soja em substituição a farinha de peixe. Os camarões foram cultivados em 12 tanques de 800 L com 250 camarões m-3, sob temperatura e aeração constantes. Após 42 dias, 36 animais (14,21 ± 0,89 g) por tratamento foram desafiados com Vibrio sp. (1 x 105 UFC mL-1 - DL10). Antes e após o desafio foi coletada hemolinfa para avaliação dos parâmetros imunológicos (título aglutinante, concentração de proteína no soro e atividade da fenoloxidase). Não houve diferença na resistência ao desafio e nos parâmetros imunológicos entre os tratamentos. Portanto, o cultivo de L. vannamei em sistema de bioflocos utilizando dietas com substituição total ou parcial com concentrado proteico de soja não afeta sua imunocompetência e susceptibilidade a infecção bacteriana.

ABSTRACT. Litopenaeus vannamei shrimp were reared in a bioflocs system and fed different levels of soybean protein concentrate as a replacement for fishmeal, and both immunological parameters of this marine shrimp and its resistance to Vibrio sp. infection (CPQBA 378-12 DRM01) were evaluated. Four different diets were formulated with 0, 33, 66 and 100 % of soybean protein concentrate as a substitute for fishmeal. Shrimp were reared in a biofloc system in twelve 800 L tanks (250 shrimp m-3) maintained at constant aeration and temperature. After 42 days, 36 animals (14.21 ± 0.89 g) per treatment were challenged with Vibrio sp. (1 x 105 CFU mL-1 - LD10), and hemolymph was collected before and after challenge to perform immunological assays (agglutination titer, concentration of protein and phenoloxidase activity). Shrimp fed with the experimental diets showed no difference in their resistance to infection and haemato-immunological parameters. Thus, rearing L. vannamei in a biofloc system on diets containing either partial or total replacement of fishmeal for soybean protein concentrate did not affect either immunocompetence or susceptibility to infection.

ABSTRACT This study aimed to assess the final body weight, weekly weight gain, yield, apparent feed efficiency, protein efficiency ratio, and feed intake of the Pacific white shrimp (Litopenaeus vannamei) fed four diets containing different levels of soy protein concentrate (SPC) as a replacement for fishmeal, reared in a super-intensive biofloc system. Diets consisted of replacing 209 g kg-1 fishmeal at 0, 33, 66, and 100% SPC. Shrimp were raised in a biofloc system using twelve experimental units stocked with 250 shrimp m-3 under constant aeration (O2>5mg L-1) and temperature (29±0.5 °C). No significant differences among treatments were observed based on water quality parameters. Shrimp fed diets with 0 and 33% substitution exhibited the highest weekly growth (1.88 and 1.79 g per week) and final weights (15.2 and 14.7 g) compared with shrimp fed the 66 and 100% replacement. A lower feed intake was observed for shrimp fed the 33% SPC diet (3.18 kg per experimental unit) compared with 0% replacement (3.62 kg). Shrimp fed the 33% replacement achieved a similar performance and lower feed intake than animals fed diet without replacement.

ABSTRACT This study evaluated the performance, immunology, and survival of the Pacific white shrimp Litopenaeus vannamei to experimental challenge to Vibrio alginolyticus based on the use of the probiotic Lactobacillus plantarum and the combined use of probiotic and butyrate. Four different diets resulted from the addition of additives: butyrate, probiotic, butyrate + probiotic, and control (no additives). The attractiveness of the diets was assessed by the percentage of positive choices and rejections, using a dual-choice Y-maze format aquarium. The shrimps were fed during four weeks and performance parameters, intestinal microbiota, and immunological parameters were all evaluated. Subsequently, the shrimps were challenged with V. alginolyticus and after 48 h, survival and immunological parameters were evaluated. The results showed increased attractiveness and intake, but only with diets supplemented with sodium butyrate. However, other diets were not rejected. No difference in performance or immunological parameters was observed among the different diets. Also, among the treatments, no difference in Vibrio spp., or total heterotrophic bacteria counts, was found in the intestinal tract. However, the lactic acid bacteria count was higher in the intestinal tract of shrimps fed diets supplemented with probiotic. After bacterial challenge, shrimp fed all diets had a greater survival when compared with the control group. Lactobacillus plantarum and sodium butyrate increase the resistance of shrimp to infection with V. alginolyticus, but do so without affecting performance, immunological parameters, or Vibrio spp., and total heterotrophic bacteria counts in the intestinal tract.

ABSTRACT The objective of this study was to evaluate the use of a diet supplemented with Lactobacillus plantarum on performance, immunological parameters, and bacterial microbiota of the digestive tract of white leg shrimp (Litopenaeus vannamei). We used six earthen ponds (1.2 ha) stocked with 14 shrimp m−2 (3 g mean weight). Three ponds received a diet supplemented with L. plantarum and three were maintained as control. The survival and feed efficiency of shrimp fed the supplemented diet were greater than that observed in shrimp fed the control diet, with survival values of 83.02±6.12% and 74.65±9.07% and feed efficiencies of 117.97±4.45% and 104.46±7.30%, respectively. However, we observed no differences in weight gain. The intestines of shrimp fed probiotics had lower counts of Vibrio spp. and higher counts of lactic acid bacteria, compared with those of control shrimp. Diets supplemented with L. plantarum alter the intestinal bacterial microbiota of shrimp, resulting in increased survival and feed efficiency.

ABSTRACTThe objective of this work was to evaluate the performance of Litopenaeus vannameifed different levels (0, 25, 50, 75, and 100%) of soybean protein concentrate (63.07% crude protein, CP) to replace fish meal-by product (61.24% CP). The study was conducted in clear water in fifteen 800 L tanks equipped with aeration systems, constant heating (29 ºC), and daily water exchange (30%). Each tank was stocked with 37.5 shrimp/m3 (3.03±0.14 g). Feed was supplied four times a day, at 6% of the initial biomass, adjusted daily. After 42 days, the weight gain of shrimp fed diets with 0 and 25% protein replacement was higher than that observed in shrimp fed 100% replacement, and there were no differences among those fed the other diets. Feed efficiency and survival did not differ among shrimp fed different protein replacements. There was a negative linear trend for growth parameters and feed intake as protein replacement with soybean protein concentrate increased. Fish meal by-product can be replaced by up to 75% of soybean protein concentrate, with no harm to the growth of Pacific white shrimp.

O objetivo deste trabalho foi isolar cepas de bactérias ácido-lácticas, com potencial probiótico do trato digestório de camarões marinhos e realizar seleção in vitro baseada em múltiplos caracteres. O ideótipo (cepa ideal proposta) foi definido por meio das maiores médias para os caracteres velocidade máxima de crescimento, contagem final de células viáveis e halo de inibição contra nove patógenos de origem continental e marinha, e pelas menores médias para os caracteres tempo de duplicação e tolerância das cepas a NaCl (1,5 e 3%), pH (6, 8 e 9) e sais biliares (5%). Foram estimadas as distâncias de Mahalanobis (D²) entre as cepas avaliadas, e as melhores foram aquelas que apresentaram menor distância do ideótipo. Foram isoladas dez cepas de bactérias identificadas bioquimicamente como Lactobacillus plantarum (3), L. brevis (3), Weissella confusa (2), Lactococcus lactis (1) e L. delbrueckii (1). As cepas de L. plantarum apresentaram amplo espectro de ação e os maiores halos de inibição, tanto para patógenos Gram-positivos quanto negativos, alta taxa de crescimento e tolerância a todos os parâmetros avaliados. Em relação ao ideótipo, L. plantarum apresentou a menor distância de Mahalanobis (D²), seguida pelas cepas de W. confusa, L. brevis, L. lactis e L. delbrueckii. Entre as cepas bacterianas avaliadas, as de L. plantarum apresentam o maior potencial para uso como probiótico para camarões marinhos.

The objective of this work was to isolate strains of lactic acid bacteria with probiotic potential from the digestive tract of marine shrimp (Litopenaeus vannamei), and to carry out in vitro selection based on multiple characters. The ideotype (ideal proposed strain) was defined by the highest averages for the traits maximum growth velocity, final count of viable cells, and inhibition halo against nine freshwater and marine pathogens, and by the lowest averages for the traits duplication time and resistance of strains to NaCl (1.5 and 3%), pH (6, 8, and 9), and biliary salts (5%). Mahalanobis distance (D²) was estimated among the evaluated strains, and the best ones were those with the shortest distances to the ideotype. Ten bacterial strains were isolated and biochemically identified as Lactobacillus plantarum (3), L. brevis (3), Weissella confusa (2), Lactococcus lactis (1), and L. delbrueckii (1). Lactobacillus plantarum strains showed a wide spectrum of action and the largest inhibition halos against pathogens, both Gram-positive and negative, high growth rate, and tolerance to all evaluated parameters. In relation to ideotype, L. plantarum showed the lowest Mahalanobis (D²) distance, followed by the strains of W. confusa, L. brevis, L. lactis, and L. delbrueckii. Among the analyzed bacterial strains, those of Lactobacillus plantarum have the greatest potential for use as a probiotic for marine shrimp.

O objetivo deste trabalho foi avaliar o uso de suplemento prebiótico, probiótico e simbiótico, na dieta de camarões marinhos (Litopenaeus vannamei) e seus efeitos sobre o crescimento, a microbiota intestinal, a resposta imune e a resistência ao desafio experimental com Vibrio alginolyticus. Foram utilizados quatro tratamentos: prebiótico inulina; probiótico Lactobacillus plantarum; simbiótico Lactobacillus plantarum + inulina; e controle. Os camarões foram distribuídos em 16 tanques de dez mil litros de água, povoados com 200 camarões cada, cultivados por seis semanas. Avaliaram-se a microbiologia do trato intestinal dos camarões e a reposta imune, antes e após o desafio com V. alginolyticus. A concentração de Vibrio spp. no trato digestório foi menor em camarões alimentados com dieta suplementada com prebiótico, probiótico e simbiótico, enquanto a concentração de bactérias acidoláticas foi superior somente nos camarões alimentados com probiótico e simbiótico. O título aglutinante do soro contra V. alginolyticus aumentou no grupo probiótico e simbiótico, antes da infecção, e foi maior em todos os tratamentos após infecção com V. alginolyticus, em comparação ao controle. Não foi observada diferença entre os tratamentos quanto aos demais parâmetros avaliados. As dietas probióticas, prebióticas e simbióticas alteram a microbiota intestinal e aumentam o título aglutinante do soro contra V. alginolyticus; contudo, não alteram a resistência ao desafio nem o crescimento dos camarões.

The objective of this work was to evaluate the use of prebiotic, probiotic, and symbiotic supplements, in the diet of shrimp (Litopenaeus vannamei), and their effects on growth, intestinal microbiota, immune response, and resistance to experimental challenge with Vibrio alginolyticus. Four treatments were used: prebiotic (inulin); probiotic (Lactobacillus plantarum); symbiotic (Lactobacillus plantarum + inulin); and a control. Shrimp were distributed in 16 tanks with ten thousand liters of water, stocked with 200 shrimp each, cultivated for six weeks. Microbiology of the intestinal tract and the immune response of shrimp were evaluated before and after the challenge with V. alginolyticus. The concentration of Vibrio spp. in the digestive tract was lower in shrimp fed prebiotic, probiotic, and symbiotic-supplemented diet, while concentration of lactic acid bacteria was higher only in shrimp fed probiotic and symbiotic-supplemented diet. The title of agglutinating serum against V. alginolyticus increased in shrimp fed the probiotic and symbiotic-supplemented diet prior to infection, and was higher in all treatments after infection with V. alginolyticus, in comparison to the control. No difference was observed between treatments for the remaining parameters. Probiotic, prebiotic, and symbiotic diets change intestinal microbiota, and increase the agglutinating serum title against V. alginolyticus; however, they change neither the shrimp resistance to challenge by V. alginolyticus nor shrimp growth.

The aim of this study was to evaluate the immune response of hybrid surubim vaccinated by intraperitoneal injection and by immersion against Aeromonas hydrophila. Vaccine was prepared with formalin-inactivated A. hydrophila. Forty eight fishes (47±9g) were distributed in 12 tanks (4 fish / tank) in the following treatments (4 tanks / treatment): unvaccinated fish, vaccinated intraperitoneally and vaccinated by immersion. After 21 days, intraperitoneally vaccinated fishes showed the highest values of total protein and immunoglobulins, agglutination titer and serum antimicrobial activity. Lysozyme concentration in the serum was higher in the fishes vaccinated by immersion than unvaccinated fishes. Intraperitoneal vaccination induced the highest immune response and could be used to improve the fish resistance against motile Aeromonas.

The objective of this study was to investigate the growth of juvenile fat snook (Centropomus parallelus) in laboratory conditions when fed a diet supplemented with the probiotic Lactobacillus plantarum. Changes in the intestinal flora, haematological parameters and growth performance were assessed using 180 fishes (54.2 ± 13.4 g each). The fishes were subjected to two treatments divided into six cages: 1) feed supplemented with probiotic, and 2) feed without probiotic (control). The temperature, dissolved oxygen and salinity were maintained at 25 ± 1 ° C, 4.0 mg.L-1 and 33 ‰, respectively. After 10 weeks of culture, the fishes fed probiotic had reduced viable culturable heterotrophic bacteria and Vibrio spp. and increased lactic acid bacteria in the intestinal tract, as well as a higher number of thrombocytes, leukocytes and lymphocytes in the blood. No significant difference was observed in the growth, survival or body composition, but the hepatosomatic index was significantly higher in the fishes fed with probiotic and control.

O objetivo deste trabalho foi avaliar a substituição de dois níveis de inclusão de farinha de peixe por outros ingredientes, nas dietas de Litopenaeus vannamei cultivados em sistema bioflocos. Foram avaliadas dietas sem uso de farinha de peixe (dieta A, 100% de substituição), com inclusão de 12,5% de farinha de peixe (dieta B, 40% de substituição) e direta controle com inclusão de 21% (dieta C, 0% de substituição). Nas dietas A e B, o farelo de soja e as farinhas de carne e vísceras foram os principais substitutos proteicos. Foram analisados os índices de desempenho dos camarões e os parâmetros físicos e químicos da água de cultivo. Os camarões alimentados com a dieta B apresentaram maior peso final (11,63±1,38 g), em comparação aos camarões alimentados com a dieta A (peso final, 9,39±0,31 g) e com a dieta C (peso final, 10,20±1,10 g). Os demais parâmetros de desempenho como produtividade, conversão alimentar e sobrevivência não apresentaram diferenças entre os tratamentos. A redução de até 40,0% da farinha de peixe pode ser feita em cultivos superintensivos de L. vannamei com bioflocos, sem interferir em seu desempenho zootécnico e na qualidade de água do cultivo.

The objective of this work was to evaluate the substitution of two fish meal inclusion levels by other ingredients, in the diets of Litopenaeus vannamei reared in a biofloc system. The following diets were evaluated: without fish meal (diet A, 100% replacent), with addition of 12.5% of fish meal (diet B, 40% replacent), and a control diet with addition of 21% (diet C, 0% replacent). In diets A and B, soybean meal and meat and viscera meals were the main protein replacement. The performance indexes of shrimps and the physical and chemical parameters of water were analyzed. Shrimp fed diet B had higher final weight (11.63±1.38 g), compared to shrimp fed a diet A (9.39±0.31 g final weight) or C (10.20±1.10 g final weight). The other parameters of performance such as yield, feed conversion and survival did not differ between treatments. The reduction of fish meal by 40.0% can be done in a L. vannamei superintensive biofloc system without interfering on their growth performance or on the water quality of the culture.