Óleos essenciais de plantas na dieta de tilápia-do-Nilo: efeitos sobre a saúde, morfologia intestinal e microbiota
Carregando...
Data
2018-02-26
Autores
Valladão, Gustavo Moraes Ramos
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Os óleos essenciais (OEs) de plantas são compostos estudados como aditivo alimentar na produção animal há alguns anos, sendo descritos por diversos autores como promotores de crescimento, imunoestimulantes e antimicrobianos. No entanto, os efeitos de sua adição na dieta de organismos aquáticos ainda são pouco conhecidos. No presente estudo, diferentes estratégias de suplementação com diferentes OEs foram testadas. No primeiro estudo, os OEs de Mentha piperita e Melaleuca alternifolia foram incorporados à dieta para tilapia-do-Nilo Oreochromis niloticus por um longo período (2 meses), e os seus efeitos sobre a saúde (parâmetros hematológicos, bioquímicos e imunológicos) e sobre o intestino (morfologia e morfometria) foram avaliados. Em um segundo momento, M. piperita, M. alternifolia, Citrus aurantium, Cymbopogon nardus, Ocimum basilicum e Thymus vulgaris foram testados in vitro contra isolados intestinais (Aeromonas hydrophila, Staphylococcus aureus e Edwardsiella tarda) da tilápia-do-Nilo para seleção daquele com maior capacidade de modular a microbiota dos peixes. O OE de Thymus vulgaris foi aquele que apresentou a maior atividade contra as bactérias testadas. Em um estudo final, o OE de Thymus vulgaris foi incorporado à dieta e fornecido por 15 dias à tilápia-do-Nilo e o efeito sobre a saúde, intestino, e também sobre a população de bactérias do gênero Bacillus no intestino foi avaliado. O primeiro experimento demonstrou que a M. piperita e a M. alternifolia foram capazes de imunoestimular componentes da resposta humoral dos peixes (ativando o sistema complemento) e a M. alternifolia ainda foi capaz de alterar a morfologia intestinal (ocasionando aumento de suas vilosidades). O OE de T. vulgaris apresentou maior atividade antibacteriana quando comparado aos outros cinco OEs testados in vitro, e quando adicionado à dieta foi capaz de imunoestimular componentes da resposta celular dos peixes (incrementando o número de leucócitos e linfócitos). Além disso, apesar de sua forte atividade antibacteriana, não foi capaz de alterar a população de bactérias benéficas do gênero Bacillus presentes no intestino. Em ambos experimentos in vivo as dietas suplementadas com OE não revelaram efeitos tóxicos aos peixes nas condições testadas. Baseado na revisão de literatura e nos resultados obtidos, conclui-se que, as suplementações com OEs foram seguras, apresentaram efeito imunoestimulante em diferentes componentes da resposta imune, puderam alterar em alguns casos a morfologia intestinal e parecem ter pouco impacto sobre a microbiota dos peixes.
Essential oils (EOs) of plants are compounds studied as food additive in animal production a few years ago. They have already been described by several authors, as growth promoter, immunostimulant and antimicrobial. However, the effects of its addition on the diet of aquatic organisms are still poorly understood. In the present study, different supplementation strategies with different EOs were tested. In the first study, the EOs of Mentha piperita and Melaleuca alternifolia were supplied for a long period (2 months) in the diet of Nile tilapia Oreochromis niloticus, and aspects of health (hematological, biochemical and immunological parameters) and intestine (morphology and morphometry) were evaluated. In a second moment, M. piperita, M. alternifolia, Citrus aurantium, Cymbopogon nardus, Ocimum basilicum and Thymus vulgaris were tested in vitro against the intestinal isolates (Aeromonas hydrophila, Staphylococcus aureus and Edwardsiella tarda) from Nile tilapia to select the one with the greatest capacity to modulate the microbiota of fish. Thymus vulgaris EO was the one that presented the highest activity against the bacteria tested. In a final study, the Thymus vulgaris EO was provided for 15 days in the diet of Nile tilapia where its effects on the health, intestine and on the population of bacteria of the genus Bacillus were evaluated. In the first experiment, it was shown that M. piperita and M. alternifolia were able to immunostimulate components of fish humoral response (activating the complement system) and M. alternifolia was still able to alter intestinal morphology (increasing their villi). The T. vulgaris EO presented higher antibacterial activity when compared to five other EOs, and when added to the diet it was able to immunostimulate components of the cellular response of fish (increasing the number of leukocytes and lymphocytes). In addition, despite its strong antibacterial activity, it was not able to alter the population of beneficial bacteria of the genus Bacillus present in the intestine. In both in vivo experiments, diets supplemented with EO showed no toxic effects on fish under the conditions tested. In conclusion, supplementation with EOs was safe, showed an immunostimulating effect on different components of the immune response, may in some cases alter the intestinal morphology and appear to have little impact on the fish microbiota.
Essential oils (EOs) of plants are compounds studied as food additive in animal production a few years ago. They have already been described by several authors, as growth promoter, immunostimulant and antimicrobial. However, the effects of its addition on the diet of aquatic organisms are still poorly understood. In the present study, different supplementation strategies with different EOs were tested. In the first study, the EOs of Mentha piperita and Melaleuca alternifolia were supplied for a long period (2 months) in the diet of Nile tilapia Oreochromis niloticus, and aspects of health (hematological, biochemical and immunological parameters) and intestine (morphology and morphometry) were evaluated. In a second moment, M. piperita, M. alternifolia, Citrus aurantium, Cymbopogon nardus, Ocimum basilicum and Thymus vulgaris were tested in vitro against the intestinal isolates (Aeromonas hydrophila, Staphylococcus aureus and Edwardsiella tarda) from Nile tilapia to select the one with the greatest capacity to modulate the microbiota of fish. Thymus vulgaris EO was the one that presented the highest activity against the bacteria tested. In a final study, the Thymus vulgaris EO was provided for 15 days in the diet of Nile tilapia where its effects on the health, intestine and on the population of bacteria of the genus Bacillus were evaluated. In the first experiment, it was shown that M. piperita and M. alternifolia were able to immunostimulate components of fish humoral response (activating the complement system) and M. alternifolia was still able to alter intestinal morphology (increasing their villi). The T. vulgaris EO presented higher antibacterial activity when compared to five other EOs, and when added to the diet it was able to immunostimulate components of the cellular response of fish (increasing the number of leukocytes and lymphocytes). In addition, despite its strong antibacterial activity, it was not able to alter the population of beneficial bacteria of the genus Bacillus present in the intestine. In both in vivo experiments, diets supplemented with EO showed no toxic effects on fish under the conditions tested. In conclusion, supplementation with EOs was safe, showed an immunostimulating effect on different components of the immune response, may in some cases alter the intestinal morphology and appear to have little impact on the fish microbiota.
Descrição
Palavras-chave
aquicultura, fitoterápicos, hematologia, imunologia, melaleuca, menta, Oreochromis niloticus, tomilho, aquaculture, phytotherapics, hematology, immunology, melaleuca, mint, thyme