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Current study investigated the effectiveness of different macrophytes as culture media for Ankistrodesmus gracilis in laboratory conditions. Significant difference (p < 0.05) was reported in cell density with regard to conventional culture medium (CHU 12 ) and macrophytes culture media. Mean cell density in NPK, Eichhornia crassipes and E. azurea media was higher (p < 0.05) than in conventional culture medium. Chlorophyll-a was higher than 1 g.L (P. cordata medium) and 1.7 g.L -1 (CHU 12 medium) for ammonium, and between 0.8 g.L -1 (CHU 12 medium) and 1.9 g.L -1 (T. domingensis medium) for total phosphorus. Results revealed inorganic fertilizer and macrophytes combined with vitamins may be effective as culture media and strongly supports the growth of Ankistrodesmus gracilis, since cell density and biochemical composition are similar to or higher than conventional culture medium (CHU 12 ). Macrophyte is a tool for aquaculture since biological wastes may be used with nutrients to improve the cultivation of microalgae.Keywords: aquatic plants, culture media, microalgae growth, biochemical composition. Resíduos biológicos de aquicultura como meio de cultura para o cultivo de Ankistrodesmus gracilis (Reinsch) KorshikovResumo O presente estudo investigou a eficácia na utilização de diferentes macrófitas como meio de cultura para Ankistrodesmus gracilis em condições laboratoriais. Foi observada diferença significativa (p < 0,05) entre a densidade celular em relação aos meios de cultura convencional (CHU 12 ) e de macrófitas. Os meios de cultura com Eichhornia crassipes, E. azurea e NPK apresentaram densidade celular maiores (p < 0,05) que o meio de cultura convencional. Os teores de clorofila-a foram superiores a 1 g.L -1 , exceto nos meios de cultura CHU 12 (0.7 ± 0.4 g.L -1 ) e de T. domingensis (0.7 ± 0.3 g.L -1 ). O nitrato diminuiu acentuadamente a partir do 7º dia de experimento. Dentre os nutrientes, amônia e o fósforo total foram os mais elevados nos meios de cultura, variando entre 0.4 g.L -1 (meio de P. cordata) a 1,7 g.L -1 (meio CHU 12 ) para amônia e, entre 0.8 g.L -1 (meio CHU 12 ) e 1,9 gL -1 (meio de T. domingensis) para o fósforo total. Os resultados do presente estudo mostraram que o uso de fertilizantes inorgânicos e macrófitas, combinados com vitaminas, pode ser eficaz como meio de cultura no crescimento de Ankistrodesmus gracilis, uma vez que a densidade celular e a composição bioquímica foram semelhantes ou superiores ao meio de cultura convencional (CHU 12 ). As macrófitas são ferramentas a serem adotadas na aquicultura, desde que os resíduos biológicos podem ser usados como nutrientes para melhorar o cultivo de microalgas.Palavras-chave: plantas aquáticas, meio de cultura, crescimento de microalga, composição bioquímica.

Fish species are impacted by multiple pathogens, and they are exposed to the chemicals used to treat these diseases at several stages during the aquaculture production cycle. This study performed hematological and histopathological evaluations of pacu (Piaractus mesopotamicus) that had been naturally infected with Aeromonas sp., Streptococcus sp., Ichthyophthirius multifiliis, Trichodina heterodentata, and Anacanthorus penilabiatus and treated with enrofloxacin and toltrazuril or with florfenicol and thiamethoxam. After 7 days of treatment from nine fishes were collected blood, via caudal puncture, and samples of the gills, liver, and kidneys. Following toltrazuril and enrofloxacin treatment, fish exhibited leukocytosis with lymphocytosis. With thiamethoxam and florfenicol treatment, the fish showed an increase in hematocrit, hemoglobin level, mean corpuscular volume, and mean corpuscular hemoglobin concentration and a decrease in red blood cells. The infected control fish presented aneurysms and a disruption of the secondary lamellae, which can cause death. The drugs used in this study stimulated the immune systems in the fish or caused electrolyte imbalances, which were temporary.

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