Phagocytotic activity and gene expression of leukocytes isolated from Astyanax lacustris / Atividade fagocítica e expressão gênica de leucócitos isolados de Astyanax lacustris

The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris­an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research­using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1ß, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1ß and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish.

A constante intensificação da aquicultura tem aumentado consideravelmente os níveis de estresse dos animais cultivados e, consequentemente, o número e a intensidade dos surtos de doenças. Logo, estudos sobre a resposta imune dos peixes, especialmente relacionados com a interação dos leucócitos de peixes com potenciais patógenos e xenobióticos, são de grande importância para o desenvolvimento de novas estratégias profiláticas e curativas. No presente trabalho, nós obtivemos sucesso ao isolar leucócitos oriundos do rim cranial de Astyanax lacustris ­ uma importante espécie de peixe Neotropical para a aquicultura e um modelo em potencial para pesquisas em aquicultura Neotropical ­ usando um protocolo de centrifugação com Percoll. Os leucócitos isolados foram incubados com lipossacarídeo (LPS) e, a expressão dos genes IL-1ß, IL-8, LysC, e LysG foi avaliada. Ainda, um novo protocolo para avaliação da atividade fagocítica dos leucócitos utilizando leveduras coradas com Vermelho Congo foi estabelecido. Os leucócitos isolados responderam à indução com LPS, exibindo up regulation dos genes IL-1ß e IL-8, duas das interleucinas pró-inflamatórias mais importantes para a resposta imune de vertebrados. Além do mais, a concentração ótima de leveduras para a avaliação da fagocitose foi de 106 células mL-1, resultando em uma capacidade fagocítica (PC) aceitável, mas sem excesso de leveduras durante o processo de contagem, garantindo maior precisão e eficácia do método. Até o presente momento, o presente estudo é o primeiro a investigar a expressão gênica e atividade fagocítica de leucócitos isolados de A. lacustris através da abordagem in vitro. Ainda, nossos resultados servirão de referência para futuros estudos em imunologia e toxicologia de peixes Neotropicais.

Effects of neutrophil extracellular traps during human respiratory syncytial virus infection in vitro / Efeitos das redes extracelulares dos neutrófilos durante a infecção in vitro pelo vírus sincicial respiratório

The human respiratory syncytial virus (hRSV) is the most common cause of severe lower respiratory tract diseases in young children worldwide, leading to a high number of hospitalizations and significant expenditures for health systems. Neutrophils are massively recruited to the lung tissue of patients with acute respiratory diseases. At the infection site, they release neutrophil extracellular traps (NETs) that can capture and/or inactivate different types of microorganisms, including viruses. Evidence has shown that the accumulation of NETs results in direct cytotoxic effects on endothelial and epithelial cells. Neutrophils stimulated by the hRSV-F protein generate NETs that are able to capture hRSV particles, thus reducing their transmission. However, the massive production of NETs obstructs the airways and increases disease severity. Therefore, further knowledge about the effects of NETs during hRSV infections is essential for the development of new specific and effective treatments. This study evaluated the effects of NETs on the previous or posterior contact with hRSV-infected Hep-2 cells. Hep-2 cells were infected with different hRSV multiplicity of infection (MOI 0.5 or 1.0), either before or after incubation with NETs (0.5–16 μg/mL). Infected and untreated cells showed decreased cellular viability and intense staining with trypan blue, which was accompanied by the formation of many large syncytia. Previous contact between NETs and cells did not result in a protective effect. Cells in monolayers showed a reduced number and area of syncytia, but cell death was similar in infected and non-treated cells. The addition of NETs to infected tissues maintained a similar virus-induced cell death rate and an increased syncytial area, indicating cytotoxic and deleterious damages. Our results corroborate previously reported findings that NETs contribute to the immunopathology developed by patients infected with hRSV.

O vírus sincicial respiratório humano (hRSV) é a causa mais comum de doenças graves do trato respiratório inferior em crianças pequenas em todo o mundo, resultando em grande número de hospitalizações e gastos significativos para os sistemas de saúde. Neutrófilos são recrutados em massa para o tecido pulmonar de pacientes com doenças respiratórias agudas. No local da infecção, eles liberam armadilhas extracelulares de neutrófilos (NETs) que podem capturar e/ou inativar diferentes tipos de microrganismos, incluindo vírus. Evidências demonstraram que o acúmulo de NETs resulta em efeitos citotóxicos diretos nas células endoteliais e epiteliais. Os neutrófilos estimulados pela proteína F do vírus sincicial respiratório (hRSV-F) geram NETs que são capazes de capturar partículas virais, reduzindo assim sua transmissão. No entanto, a produção maciça de NETs obstrui as vias aéreas e aumenta a gravidade da doença. Assim, um maior conhecimento sobre os efeitos das NETs durante as infecções por hRSV é essencial para o desenvolvimento de novos tratamentos específicos e eficazes. Este estudo avaliou os efeitos das NETs no contato prévio ou posterior à infecção de células Hep-2 com hRSV. As células Hep-2 foram infectadas com diferentes quantidades de hRSV (multiplicidade de infecção ou MOI 0,5 ou 1,0), antes ou após a incubação com NETs (0,5–16 μg/mL). Células infectadas e não tratadas mostraram redução da viabilidade celular e intensa coloração com azul de tripano, que foi acompanhada pela formação de sincícios numerosos e grandes. O contato prévio entre as NETs e as células não resultou em efeito protetor. As células em monocamadas mostraram um número e área de sincícios reduzidos, mas a morte celular foi semelhante àquela apresentada por células infectadas e não tratadas. A adição de NETs aos tecidos infectados manteve taxa de morte celular e formação de sincícios [...].

Diarrhea in cats infected with Cystoisospora spp. - evaluation of the neutrophil-to-lymphocyte ratio and monocyte-to-lymphocyte ratio

Background: Cystoisospora spp. is considered a potential pathogen to cause diarrhoea in cats, and the disease occurs clinically, especially in young, weak and immunocompromised cats. The present study aimed to evaluate the clinical utility and diagnostic roles of neutrophil-to-lymphocyte ratio (NLR) and monocyte-to-lymphocyte (MLR) ratios in diarrheal cats infected with Cystoisospora spp. Materials, Methods & Results: Twenty-five cats with diarrhea due to infection caused by Cystoisospora spp. and 15 healthy cats were included in this study. The anamnesis, clinical and laboratory findings of all cats were recorded. A clinical severity score was generated for diarrheal cats, which included activity, appetite, presence of vomit, and faecal consistency. Also, cats infected with Cystoisospora spp. were classified as systemic inflammatory response syndrome (SIRS) positive (+) and SIRS (-) group according to the presence of at least 3 of the SIRS criteria. The Cystoisospora spp. oocysts were diagnosed by direct smear and simple faecal flotation. Cats found positive for other parasitic and protozoal agents by faeces examination were excluded from the study. Complete blood counts (CBC) were performed with an automated blood cell counter for all cats. Blood smears were prepared (with May-Grunwald Giemsa) from samples, and the CBC results were confirmed microscopically (obj.100x). White blood cell (WBC), neutrophil, lymphocyte and monocyte counts were recorded directly from the CBC. The neutrophil-to-lymphocyte ratio was calculated as the ratio of the absolute neutrophil count to the absolute lymphocyte count. The monocyte-to-lymphocyte was calculated as the absolute monocyte count ratio to the absolute lymphocyte count. White blood cell (P = 0.015), neutrophil (P = 0.001), monocyte (P = 0.033), NLR (P = 0.000) and MLR (P = 0.042) of diarrheal cats infected with Cystoisospora spp. were significantly higher than in the healthy group. There was no significant difference between groups in the lymphocyte counts (P > 0.05). SIRS (+) group had statistically significantly higher WBC (P = 0.014), neutrophil counts (P = 0.000), NLR (P = 0.000) and MLR (P = 0.037) than the healthy group. Also, neutrophil counts and NLR of the SIRS (+) group were statistically significantly higher than the SIRS (-) group (P = 0.032; P = 0.001, respectively). However, there was no significant difference SIRS (+), SIRS (-), and healthy groups regarding lymphocyte and monocyte counts (P > 0.05). The clinical severity of the disease positively correlated with NLR and MLR. Also, the best cut-off value of NLR to predict SIRS was > 1.67, with 92.86% sensitivity and 84.62% specificity. MLR was not a useful predictor for SIRS. Discussion: NLR and MLR are parameters derived from complete blood count. In recent years, they have been used in human and veterinary medicine as a biomarker in the diagnosis, prognosis and treatment follow-up of various diseases and provide valuable information about inflammation. In cats, there are limited studies on NLR, and to our knowledge, there are no studies on MLR. The current study suggests that NLR and MLR may be used to determine the severity of the inflammatory condition in diarrheal cats infected with Cystoisospora spp., and NLR is a useful marker for predicting SIRS status in these cats. In addition, this study also will contribute to larger-scale studies in the future.

Effects of neutrophil extracellular traps during human respiratory syncytial virus infection in vitro / Efeitos das redes extracelulares dos neutrófilos durante a infecção in vitro pelo vírus sincicial respiratório

The human respiratory syncytial virus (hRSV) is the most common cause of severe lower respiratory tract diseases in young children worldwide, leading to a high number of hospitalizations and significant expenditures for health systems. Neutrophils are massively recruited to the lung tissue of patients with acute respiratory diseases. At the infection site, they release neutrophil extracellular traps (NETs) that can capture and/or inactivate different types of microorganisms, including viruses. Evidence has shown that the accumulation of NETs results in direct cytotoxic effects on endothelial and epithelial cells. Neutrophils stimulated by the hRSV-F protein generate NETs that are able to capture hRSV particles, thus reducing their transmission. However, the massive production of NETs obstructs the airways and increases disease severity. Therefore, further knowledge about the effects of NETs during hRSV infections is essential for the development of new specific and effective treatments. This study evaluated the effects of NETs on the previous or posterior contact with hRSV-infected Hep-2 cells. Hep-2 cells were infected with different hRSV multiplicity of infection (MOI 0.5 or 1.0), either before or after incubation with NETs (0.5–16 μg/mL). Infected and untreated cells showed decreased cellular viability and intense staining with trypan blue, which was accompanied by the formation of many large syncytia. Previous contact between NETs and cells did not result in a protective effect. Cells in monolayers showed a reduced number and area of syncytia, but cell death was similar in infected and non-treated cells. The addition of NETs to infected tissues maintained a similar virus-induced cell death rate and an increased syncytial area, indicating cytotoxic and deleterious damages. Our results corroborate previously reported findings that NETs contribute to the immunopathology developed by patients infected with hRSV.(AU)

O vírus sincicial respiratório humano (hRSV) é a causa mais comum de doenças graves do trato respiratório inferior em crianças pequenas em todo o mundo, resultando em grande número de hospitalizações e gastos significativos para os sistemas de saúde. Neutrófilos são recrutados em massa para o tecido pulmonar de pacientes com doenças respiratórias agudas. No local da infecção, eles liberam armadilhas extracelulares de neutrófilos (NETs) que podem capturar e/ou inativar diferentes tipos de microrganismos, incluindo vírus. Evidências demonstraram que o acúmulo de NETs resulta em efeitos citotóxicos diretos nas células endoteliais e epiteliais. Os neutrófilos estimulados pela proteína F do vírus sincicial respiratório (hRSV-F) geram NETs que são capazes de capturar partículas virais, reduzindo assim sua transmissão. No entanto, a produção maciça de NETs obstrui as vias aéreas e aumenta a gravidade da doença. Assim, um maior conhecimento sobre os efeitos das NETs durante as infecções por hRSV é essencial para o desenvolvimento de novos tratamentos específicos e eficazes. Este estudo avaliou os efeitos das NETs no contato prévio ou posterior à infecção de células Hep-2 com hRSV. As células Hep-2 foram infectadas com diferentes quantidades de hRSV (multiplicidade de infecção ou MOI 0,5 ou 1,0), antes ou após a incubação com NETs (0,5–16 μg/mL). Células infectadas e não tratadas mostraram redução da viabilidade celular e intensa coloração com azul de tripano, que foi acompanhada pela formação de sincícios numerosos e grandes. O contato prévio entre as NETs e as células não resultou em efeito protetor. As células em monocamadas mostraram um número e área de sincícios reduzidos, mas a morte celular foi semelhante àquela apresentada por células infectadas e não tratadas. A adição de NETs aos tecidos infectados manteve taxa de morte celular e formação de sincícios [...].(AU)

Hematological parameters in endurance horses pre and post 120 km race / Parâmetros hematológicos em cavalos de enduro pré e pós prova de 120 km

The endurance discipline has the shortest history in Bulgaria compared with other disciplines of equestrian sports. Endurance competitions are held over distances from 40 km to 160 km. The present study focused on the effect of exercise on horses over a distance of 120 km. Changes in the following hematological parameters were investigated:Leukocytes (WBC, g/l); Erythrocytes (RBC, T/l); Platelets (PLT, g/l); Hemoglobin (Hb, g/l); Hematocrit (HCT,%); Mean corpuscular volume(MCV, fl); Mean corpuscular hemoglobin(MCH, pg); Mean cell hemoglobin concentration(MCHC, g/l), Leukogram (Eos; Bas; Neu; Lym; Mon,%) as well as some electrolytes and hormone concentration. The study aimed to establish the changes in these indicators' values before and after the competition. Analysis of the haemogram showed a significant increase in the mean values of 4 of the indicators under study. No significant differences were established in MCV, MCH and MCHC. A decrease was found in the number of Lym, Eos, and Mon and a significant increase in Neu after the competition. The concentration of electrolytes (Ca, Na and K) in the blood serum decreased, and the levels of CK and LDH significantly increased.(AU)

A disciplina de resistência tem a história maiscurta na Bulgária em comparação com outras disciplinas de esportes equestres. As competições de resistência são realizadas em distâncias de 40 km a 160 km. O presente estudo focou no efeito do exercício em cavalos em uma distância de 120 km. Foram investigadas alterações nos seguintes parâmetros hematológicos: Leucócitos (g/l); Eritrócitos (T/l); Plaquetas (g/l); Hemoglobina (g/l); Hematócrito (%); Volume corpuscular médio (VCM, fl); Hemoglobina corpuscular média (HCM, pg); Concentração de hemoglobina corpuscular média(CHCM, g/l), Leucograma (Eos; Bas; Neu; Lin; Mon,%), bem como alguns eletrólitos e concentração hormonal. O estudo teve como objetivo estabelecer as mudanças nos valores desses indicadores antes e depois da competição. A análise do hemograma mostrou um aumento significativo nos valores médios de 4 dos indicadores estudados. Não foram encontradas diferenças significativas no VMC, HCM e CHCM. Foi encontrada uma diminuição no número de Lin, Eos e Mon e um aumento significativo em Neu após a competição. A concentração de eletrólitos (Ca, Na e K) no soro sanguíneo diminuiu e os níveis de Creatina Quinase (CK) e Lactato Desidrogenase (LDH) aumentaram significativamente.(AU)

Thromboembolism in a bitch - diagnosis by infrared thermography

Background: Thermography is a noninvasive, non-contact, painless, and non-ionizing imaging technique that records cutaneous thermal patterns generated by infrared emission of the surface. The surface heat is closely related to dermal microcirculation. Thromboembolism is responsible for important changes in the thermal pattern of the body surface due to physical obstruction of blood flow, being the main complication in immune-mediated hemolytic anemia. The aim of this paper is to report a dog with thrombus in his left forelimb secondary to idiopathic hemolytic anemia, whose diagnostic screening was performed through infrared thermography. Case: A 9-year-old mixed breed bitch was referred to a veterinary hospital with a history of emesis, diarrhea and dark-colored urine for 2 days. The complete blood count showed hypochromic macrocytic anemia (hematocrit [HTC] 28%, reference: 37 to 55%) with the presence of nucleated erythrocyte (14/100 leukocytes, reference: 0 to 5/100 leukocytes), polychromasia and spherocytes. Leukocytosis (28,300 mm³, reference: 6,000 to 17,000 mm³) by neutrophilia with left deviation and toxic granulations was also present, in addition to hemoglobinuria at urine exam. Therefore, treatment for immune-mediated hemolytic anemia (IMHA) was instituted. After 2 days, the animal returned with acute functional impairment of the left forelimb. Physical examination revealed that the limb was cold, without pulse, proprioception, reflexes, and deep pain. New blood analyses revealed decreased hematocrit (HTC 17%, reference: 37 to 55%), and increased total leukocyte number (57,000 mm3, reference: 6,000 to 17,000 mm³). Infrared thermography revealed an important temperature difference between the limbs, with the affected limb temperature considerably lower (31.3ºC) when compared to the contralateral limb (35.0ºC). Thermography showed the site of the thrombus in the medial portion of the limb (cephalic vein), where the catheter had been placed for fluid therapy. Due to the severity of the condition, the bitch was submitted to amputation surgery, which occurred without complications. The patient had a good response to treatment, with decreased signs of hemolysis and hypercoagulability. The medications were slowly withdrawn, and the clinical discharge occurred after 4 weeks. Discussion: In humans, thermography has been widely used in the assessment of thrombotic diseases, contributing to diagnosis, localization, and prognosis. In veterinary medicine, however, the use of this tool in the diagnosis of thromboembolism is still rare. The difference of 3.7°C between the affected and contralateral limb was objectively verified using thermography. A minimum difference of 2.4°C between limbs has high sensitivity and specificity for diagnosing thromboembolism and occurs due to the reduction in local blood flow. In the present case this tool was essential for the anatomical location of the thrombus, which was in the middle third of the forearm, and allowed an adequate surgical planning. It is known that the main complication of IMHA is thromboembolism. Its predisposing factors include venous stasis, endothelial damage, and hypercoagulability, being exacerbated by cage confinement, decubitus and presence of a peripheral venous catheter. The reported case corroborates at least one of these factors since it had a peripheral venous catheter in the left forelimb, which later showed absence of pulse, spinal reflexes, pain and proprioception. The thermography showed to be an objective, rapid and non-invasive tool to diagnose and precisely locate the thrombus, which allowed for adequate treatment and surgical planning for the case. To the best of our knowledge, this is the first report about use of thermography to diagnose thromboembolism secondary to immune-mediated hemolytic anemia in a dog.

Efficacy of Carapa guianensis oil (Meliaceae) against monogeneans infestations: a potential antiparasitic for Colossoma macropomum and its effects in hematology and histopathology of gills / Eficácia do óleo de Carapa guianensis (Meliaceae) contra infestações de monogenéticos: um potencial antiparasitário para Colossoma macropomum e seus efeitos na hematologia e histopatologia de brânquias

This study evaluated the efficacy of therapeutic baths with Carapa guianensis (andiroba) oil against monogeneans of Colossoma macropomum (tambaqui), as well as the hematological and histological effects on fish. Among the fatty acids identified in C. guianensis oil, oleic acid (53.4%) and palmitic acid (28.7%) were the major compounds, and four limonoids were also identified. Therapeutic baths of 1 hour were performed for five consecutive days, and there was no fish mortality in any of the treatments. Therapeutic baths using 500 mg/L of C. guianensis oil had an anthelmintic efficacy of 91.4% against monogeneans. There was increase of total plasma protein and glucose, number of erythrocytes, thrombocytes, leukocytes, lymphocytes and number of monocytes and decrease in mean corpuscular volume. Histological changes such as epithelium detachment, hyperplasia, lamellar fusion and aneurysm were found in the gills of tambaqui from all treatments, including controls with water of culture tank and water of culture tank plus iso-propyl alcohol. Therapeutic baths with 500 mg/L of C. guianensis oil showed high efficacy and caused few physiological changes capable of compromising fish gill function. Results indicate that C. guianensis oil has an anthelmintic potential for control and treatment of infections by monogeneans in tambaqui.(AU)

Avaliou-se a eficácia de banhos terapêuticos com óleo de Carapa guianensis (andiroba) contra monogenéticos de Colossoma macropomum (tambaqui), bem como os efeitos hematológicos e histológicos. Dentre os ácidos graxos identificados no óleo de C. guianensis, ácido oleico (53,4%) e ácido palmítico (28,7%) foram os compostos majoritários, e quatro limonoides também foram identificados. Banhos terapêuticos de 1 hora foram realizados por cinco dias consecutivos, não havendo mortalidade de peixes em nenhum dos tratamentos. Banhos terapêuticos, com 500 mg/L de óleo de C. guianensis, apresentaram eficácia de 91,4% contra monogenéticos. Houve aumento dos níveis plasmáticos de proteína total e glicose, número de eritrócitos, trombócitos, leucócitos, linfócitos e número de monócitos e diminuição do volume corpuscular médio. Alterações histológicas, como descolamento do epitélio, hiperplasia, fusão lamelar e aneurisma, foram encontradas nas brânquias de tambaqui de todos os tratamentos, incluindo os controles com água do tanque de cultivo e água do tanque de cultivo + álcool isopropílico. Banhos terapêuticos com 500 mg/L de óleo de C. guianensis mostraram alta eficácia e causaram poucas alterações fisiológicas capazes de comprometer a função branquial dos peixes. Esses resultados indicam que o óleo de C. guianensis apresenta potencial anti-helmíntico para controle e tratamento de infecções causadas por monogenéticos em tambaqui.(AU)

Experimental model of nephropathy associated with diabetes mellitus in mice

Purpose: Nontransmissible chronic diseases, such as diabetes mellitus (DM) and nephropathy, affect a significant portion of the population, often treated due to injuries that require healing and regeneration. To create an experimental model of associated comorbidities, for healing and regeneration studies, protocols for induction of nephropathy by ischemia and reperfusion (I/R) and induction of DM by injection of streptozotocin (STZ) were associated. Methods: Sixty-four mice (Mus musculus), female, adult, Swiss strain, weighing approximately 20 g, were divided into four groups: G1: control (n = 24), G2: nephropathy group (N) (n = 7), G3, DM (n = 9), and G4: N+DM (n = 24). Arteriovenous stenosis (I/R) of the left kidney was performed as the first protocol. The animals received a hyperlipidemic diet for 7 days after the injection of STZ (150 mg/kg, via i.p.) and an aqueous glucose solution (10%) for 24 h. The animals in the G3 and G4 groups were observed for 14 days before receiving the diet and STZ. The evolution of nephropathy was observed using a urine test strip and the DM, through the analysis of blood glucose with a reagent strip on a digital monitor. Results: The ischemic induction protocols of nephropathy and DM with STZ, associated, were sustainable, low-cost, and without deaths. There were alterations compatible with initial renal alterations, in the first 14 days, such as increased urinary density, pH alteration, presence of glucose, proteins and leukocytes, when compared to the control group. DM was confirmed by the presence of hyperglycemia 7 days after induction and its evolution after 14 days. The animals in the G4 group showed constant weight loss when compared to the other groups. It was possible to observe morphological alterations in the kidneys submitted to I/R, regarding coloration, during surgery and after the end of the observation period, in the volume and size of the left kidney, when compared to the contralateral kidney. Conclusion: It was possible to induce nephropathy and DM associated in the same animal, in a simple way, confirmed with rapid tests, without losses, providing a basis for future studies.

Effects of supplementation with vitamins C and E on the acute inflammatory response in Piaractus mesopotamicus / Efeitos da suplementação com vitaminas C e E na resposta inflamatória aguda em Piaractus mesopotamicus

Vitamins C and E are potent antioxidants that reduces the harmful effects of stress in several species including fish. In this study, it was evaluated the effect of vitamins C, E and their combination in the acute aerocystitis induced by inactivated Aeromonas hydrophila in pacu. 288 fish were distributed into 4 groups supplemented for 90 days: G1-control; G2- supplemented with 500 mg of Vitamin C; G3-supplemented with 500 mg of Vitamin E; G4-supplemented with 500 mg of Vitamin C + 500 mg of Vitamin E. The fish were divided in three groups, the first was not inoculated; second were inoculated in the swim bladder with 3 x 109 CFU of inactivated A. hydrophila and the last one with saline. The inflammatory exudate was collected from the swim bladder for assessment of cellular component and cytochemistry. The results showed higher accumulation of leukocytes in fish inoculated with bacteria. Cytochemistry was effective identifying thrombocytes, lymphocytes, macrophages and, granulocytes present in the exudate. It was also observed fish that received supplementation with vitamins presented higher accumulation of total cells in the exudate with a predominance of lymphocytes and thrombocytes. These results suggested that supplementation with vitamins improved the immunological responses.

As vitaminas C e E são potentes antioxidantes que reduzem os efeitos nocivos do estresse em várias espécies, incluindo peixes. Neste estudo, avaliou-se o efeito das vitaminas C, E e sua combinação na aerocistite aguda induzida por Aeromonas hydrophila inativada em pacu. 288 peixes foram distribuídos em 4 grupos suplementados por 90 dias: G1-controle; G2- suplementado com 500 mg de Vitamina C; G3-suplementado com 500 mg de Vitamina E; G4-suplementado com 500 mg de Vitamina C + 500 mg de Vitamina E. Os peixes foram divididos em três grupos, o primeiro não foi inoculado; o segundo foi inoculado na bexiga natatória com 3 x 109 UFC de A. hydrophila inativada e a última com soro fisiológico. O exsudato inflamatório foi coletado da bexiga natatória para avaliação do componente celular e citoquímica. Os resultados mostraram maior acúmulo de leucócitos nos peixes inoculados com a bactéria. A citoquímica foi eficaz na identificação de trombócitos, linfócitos, macrófagos e granulócitos presentes no exsudato. Também foi observado que os peixes que receberam suplementação com vitaminas apresentaram maior acúmulo de células totais no exsudato com predominância de linfócitos e trombócitos. Esses resultados sugeriram que a suplementação com vitaminas melhorou as respostas imunológicas.

Mansoa alliacea extract improves the growth performance and innate immune response of Arapaima gigas challenged with Aeromonas hydrophila and handling stress / Extrato de Mansoa alliacea melhora o desempenho de crescimento e resposta imunológica de Arapaima gigas desafiado com Aeromonas hydrophila e estresse de manejo

This study investigated the effects of dietary supplementation with Mansoa alliacea hydroalcoholic extracts on growth, blood and immune parameters of Arapaima gigas. Fish were fed for 30 days with diets enriched with 0, 4, 8, and 12 g kg-1 of M. alliacea hydroalcoholic extract and subjected to infection with Aeromonas hydrophila and handling stress. Fish fed with 8 g kg-1 of extract showed significant increase in final weight, specific growth rate and feed efficiency when compared to the other groups. Glucose, triglycerides, total proteins, and globulins increased significantly in fish fed with 8 g kg-1 of extract, whereas albumin decreased. The number of thrombocytes increased significantly with the dietary supplementation of 8 and 12 g kg-1 of extract. After the challenge with A. hydrophila and handling stress, fish fed with 8 g kg-1 of extract had significantly higher levels of glucose, globulins, and albumins, and fish fed with 8 and 12 g kg-1 of extract showed an increment of respiratory burst. Triglyceride levels dropped significantly in fish fed with 4, 8, and 12 g kg-1 of extract, whereas the number of neutrophils increased, and total thrombocytes, leukocytes and lymphocytes were higher in fish fed with 12 g kg-1 of extract. Dietary supplementation with M. alliacea extract at 8 g kg-1 was efficient in improving the growth and innate immunity of A. gigas, being potentially useful in fish farming to control the development of A. hydrophila infections.(AU)

Investigou-se os efeitos da suplementação com extrato hidroalcólico de Mansoa alliacea sobre o crescimento e parâmetros sanguíneos e imunológicos de Arapaima gigas. Os peixes foram alimentados por 30 dias com dietas enriquecidas com 0, 4, 8 e 12 g kg-1 de extrato hidroalcoólico de M. alliacea e submetidos à infecção por Aeromonas hydrophila e estresse de manejo. Os peixes alimentados com 8 g kg-1 de extrato apresentaram aumento significativo no peso final, taxa de crescimento específico e eficiência alimentar quando comparados aos demais grupos. Glicose, triglicerídeos, proteínas totais e globulinas aumentaram significativamente nos peixes alimentados com 8 g kg-1 de extrato, enquanto a albumina diminuiu. O número de trombócitos aumentou significativamente com a suplementação dietética de 8 e 12 g kg-1 de extrato. Após infecção com A. hydrophila e estresse de manejo, os peixes alimentados com 8 g kg-1 de extrato apresentaram níveis significativamente mais altos de glicose, globulinas e albuminas, e os peixes alimentados com 8 e 12 g kg-1 de extrato apresentaram incremento de explosão respiratória. Os níveis de triglicerídeos decresceram nos peixes alimentados com 4, 8 e 12 g kg-1 de extrato, enquanto o número de neutrófilos aumentou, e o número total de trombócitos, leucócitos e linfócitos foi maior nos peixes alimentados com 12 g kg-1 de extrato. A suplementação com a 8 g kg-1 de extrato de M. alliacea foi eficiente em melhorar o crescimento e a imunidade inata de A. gigas, sendo potencialmente útil na piscicultura para controlar o desenvolvimento de infecções por A. hydrophila.(AU)