This study evaluated the acute inflammatory response induced by carrageenin in the swim bladder of Nile tilapia supplemented with the mixture of natural extracts of propolis and Aloe barbadensis (1:1) at a concentration of 0.5%, 1% and 2% in diet during 15 days. Thirty-six fish were distributed into four treatments with three replicates: fish supplemented with 0.5% of admix of extracts of propolis and Aloe (1:1) injected with 500 µg carrageenin; fish supplemented with 1% of admix of extracts of propolis and Aloe (1:1) injected with 500 µg carrageenin; fish supplemented with 2% of admix of extracts of propolis and Aloe (1:1), injected with 500 µg carrageenin and unsupplemented fish injected with 500 µg carrageenin. Six hours after injection, samples of blood and exudate from the swim bladder of fish were collected. It was observed an increase in the leukocyte count in the swim bladder exudate of fish supplemented with extracts of propolis and Aloe injected with carrageenin. The most frequent cells were macrophages followed by granular leukocytes, thrombocytes and lymphocytes. Supplementation with propolis and Aloe to 0.5% caused a significant increase in the number of cells on the inflammatory focus mainly macrophages, cells responsible for the phagocytic activity in tissues, agent of innate fish immune response.Keywords: inflammation, carrageenin, swim bladder, propolis, Aloe.Inflamação aguda e resposta hematológica em tilápias do Nilo alimentadas com extratos naturais de própolis e Aloe barbadensis suplementados na dieta ResumoEste estudo avaliou a resposta inflamatória aguda induzida por carragenina na bexiga natatóriade tilápia do Nilo suplementada com a mistura dos extratos naturais de própolis e Aloe barbadensis (1:1), nas concentrações de 0,5%, 1% e 2% na dieta durante o período de 15 dias. Trinta e seis peixes foram distribuídos em quatro tratamentos com três repetições: peixes suplementados com 0,5% da mistura dos extratos de própolis e Aloe (1:1) injetados na bexiga natatória com 500 µg de carragenina; peixes suplementados com 1% da mistura dos extratos de própolis e Aloe (1:1) injetados na bexiga natatória com 500 µg de carragenina; peixes suplementados com 2% da mistura dos extratos de própolis e Aloe (1:1) injetados na bexiga natatória com 500 µg de carragenina e peixes não suplementados injetados na bexiga natatória com 500 µg de carragenina. Seis horas após as injeções foram coletadas amostras de sangue e exsudato da bexiga natatória dos peixes. Foi observado aumento na contagem de leucócitos no exsudato da bexiga natatória de peixes suplementados com os extratos de própolis e Aloe injetados com carragenina. As células mais frequentes foram os macrófagos seguidos pelos leucócitos granulares, trombócitos e linfócitos. A suplementação com própolis e Aloe a 0,5% provocou aumento significativo no número de células no foco inflamatório, principalmente dos macrófagos, células responsáveis pela atividade fagocitária nos tecidos, agente da resposta imune inata nos peixes.Palavras-chave: inflamação,...

ABSTRACT. The objective of this study was to investigate the influence of dietary supplementation with propolis on hematology and number and area of melanomacrophage centers in spleen and kidney of tilapia. After acclimation, fish (24.7 ± 7.4 g mean weight) were distributed in 6 tanks 100 L, 6 fish per tank, in triplicate, at a temperature 24.0 ± 2.8 o C, with two treatments: Fish fed 2% propolis supplemented diet and fish fed non-supplemented diet. To monitor the evolution of the effects, two samples were collected: half of the fish from each treatment were used after 15 days and the other half after 21, composing two feeding times. After each feeding time, blood, spleen and kidney were collected. After twenty one days feeding on 2% propolis supplemented diet, fish showed a lower number of total leukocytes and lymphocytes and an increase in the total erythrocytes number. Fish fed supplemented diet presented an increased number of melanomacrophage centers. We observed hemosiderin in all spleen samples. Kidney showed no significant difference on the presence of melanomacrophage centers containing hemosiderin. Despite these changes, the fish health status was not affected. The results showed that propolis supplementation in the diet of Nile tilapia may be physiologically feasible.