Ocimum gratissimum essential oil in the transport water of Brycon hilarii: implications at water quality, blood parameters and residues in tissue and plasma.

Transporting live fish is a common practice in fish farming, and is certainly one of the main problems that affect fish homeostasis. In this scenario, the use of natural additives has shown promise in improving fish resistance to adverse situations. This study aimed to assess the impact of Ocimum gratissimum L. essential oil (OGEO) on water quality, hematological parameters, and residue levels in the plasma, fillet, and liver of juvenile piraputanga (Brycon hilarii) during a two-hour transportation period. The fish were divided into plastic bags (4 L) and exposed to three different OGEO concentrations (10, 20, and 30 mg L-1), while a control group received no OGEO (three repetitions each). After the two-hour transportation, blood samples were collected, as well as portions of the fillet and liver for quantifying essential oil compounds, which were also measured in the plasma. Oxygen levels remained high throughout the transportation period, in all groups, while the pH decreased. Hemoglobin, MCHC, and MCH increased in fish exposed to OGEO concentrations of 20 and 30 mg L-1, compared to the control group. However, lymphocyte counts and the concentrations of essential oil compounds in plasma, fillet, and liver increased with higher OGEO concentrations. The use of 10 mg L-1 OGEO in the two-hour transport water is promising to ensure the survival and well-being of Brycon hilarii juveniles (weighing 16 g), showing to be safe and effective. The residual concentration of eugenol the major compound of OGEO in the fillet remains below the maximum limit of the recommended daily intake.

In vitro culture and morphology of Neoechinorhynchus buttnerae (Eoacanthocephala: Neoechinorhynchidae) collected from the intestine of tambaqui (Colossoma macropomum) farmed in the Brazilian Amazon.

The tambaqui (Colossoma macropomum) is a species of great economic importance for fish farming in the Brazilian Amazon, and acanthocephaliasis caused by Neoechinorhynchus buttnerae (Golvan 1956) represents an obstacle to its production due to it causing severe morphological damage to the intestinal mucosa, thus impairing the absorption of nutrients and causing weight loss in the fish. Therefore, the establishment of in vitro protocols for evaluation of anthelmintic drugs is the first step to development of effective measures for in vivo control of this endoparasite. The present study evaluated the in vitro survival of N. buttnerae maintained in Eagle's minimum essential medium under different culture conditions. Three assays were carried out to evaluate whether temperature, supplementation with the antibiotics penicillin and streptomycin, and culture medium replacement or no replacement would influence the motility and morphology of the acanthocephalans. The results of the Kaplan-Meier analysis indicated that the use of culture in minimum essential medium together with penicillin and streptomycin prolonged the parasite's survival when kept at temperatures of 24 °C or 28 °C. We describe herein for first time an alternative protocol that is ideal for the in vitro culture of N. buttnerae. As such, this protocol ensures greater reliability in further in vitro studies with N. buttnerae.

Acute toxicity of essential oils of Aloysia triphylla (L'Hér.) Britton, Lippia gracilis Schauer, and Piper aduncum L. in Colossoma macropomum (Cuvier, 1818).

The aim of this study was to determine the acute toxicity of the essential oils (EOs) of Aloysia triphylla, Lippia gracilis and Piper aduncum in juvenile tambaqui (Colossoma macropomum), and evaluate the possible histopathological alterations in their gills. For the acute toxicity tests, juvenile tambaqui (n=24/treatment) were distributed in six treatments with three replicates, which comprised the control and five EO concentrations of A. triphylla (60, 80, 100, 120 and 140 mg L-1), L. gracilis (35, 40, 45, 50 and 55 mg L-1) and P. aduncum (42.5, 45, 47.5, 50 and 52.5 mg L-1), with an exposure period of 4 h. The mortality rate and severity of damage to the tambaqui gills were proportional to the increase in the concentration of the EO, with LC50-4 h values estimated at 109.57 mg L -1 for A. triphylla, 41.63 mg L -1 for L. gracilis and 48.17 mg L -1 for P. aduncum. The main morphological damages observed in the gills of the tambaqui exposed to the three EOs, were Grade I: hypertrophy and hyperplasia of lamellar epithelial cells, lamellar fusion, epithelial detachment, capillary dilation and constriction, proliferation of chloride cells and mucosal cells and edema; in low frequency Grade II damage as epithelial rupture and lamellar aneurysm. Necrosis (Grade III damage) was observed only in gill lamellae exposed to P. aduncum EO (47.5, 50.0 and 52.5 mg L-1). Concentrations of EOs below LC50-4 h can be used sparingly, for short periods of exposure for the treatment of diseases in tambaqui breeding.

Antimicrobial resistance profile of Aeromonas spp. isolated from asymptomatic Colossoma macropomum cultured in the Amazonas State, Brazil.

Bacterial diseases are important factors that limit productivity in aquaculture. To reduce negative economic impacts, fish farmers use antimicrobials, often indiscriminately, and this action has led to bacterial resistance to drugs. The objectives of this study were to isolate and identify the main putative pathogenic bacterial species in tambaqui (Colossoma macropomum), establish the profile of resistance to antimicrobials by the methods of disc diffusion, and determine the minimum inhibitory concentration (MIC) values. Two hundred and ninety asymptomatic fish were collected between March and November 2015 from ten fish farms in the Amazonas state (Brazil). Of the total strains recovered from tambaqui, seven were identified as Aeromonas spp. by sequencing the 16S rRNA gene. These seven isolates showed resistance to ampicillin, 28% to erythromycin, and 28% to sulfonamide. Additionally, the seven isolates showed a MIC higher than the range evaluated for amoxicillin, penicillin, novobiocin, tylosin tartrate, and clindamycin, and 85% showed resistance to erythromycin. The results of this study indicate the need to increase the awareness of fish farmers and, most importantly, the government, about the lack of drug regulations for use in aquaculture, and good management practices, so the indiscriminate prophylactic and systemic use of antimicrobials be inhibited.

Fauna parasitária e relação parasito-hospedeiro de tambaquis criados na região do Baixo São Francisco, nordeste do Brasil / Parasitic fauna and parasite-host relationship of tambaqui reared in São Francisco river basin, Brazilian northeast

Este trabalho teve como objetivo avaliar a fauna parasitária de tambaquis na região do Baixo São Francisco-AL/SE-Brasil e correlacionar os índices de prevalência e intensidade média com fatores bióticos e abióticos. Foram coletados 252 espécimes para análise parasitológica de 10 pisciculturas. Os parasitos foram contabilizados, identificados, e determinaram-se os índices de prevalência e intensidade média, que foram correlacionados com fatores bióticos e abióticos. Dos peixes coletados, 65,5% estavam parasitados por pelo menos um táxon. Foram encontrados 10 táxons: Monogeneas, Ichthyophthirius multifiliis, tricodinídeos, Piscinoodinium pillulare, Ichthyobodo sp., Dolops carvalhoi, Lernaea cyprinacea, Procamallanus (Spirocamallanus) inopinatus, Henneguya sp. e Myxobolus sp. As maiores prevalências foram encontradas para Monogeneas (49,2%) e Myxobolus sp. (31,5%). Correlações negativas entre prevalência e fatores bióticos (peso e comprimento) foram observadas para Monogeneas (r2= -0,49; r2= -0,43), Myxobolus sp. (r²= -0,46; r²= -0,39) e Henneguya sp. (r²= -0,41; r²= -0,39). O fator abiótico temperatura apresentou correlação negativa com as prevalências de Lernaea cyprinacea (r= -0,39) e tricodinídeos (r= -0,33), enquanto a condutividade elétrica apresentou correlação positiva (r= 0,40) com a prevalência de tricodinídeos. Conclui-se que a fauna parasitária dos tambaquis cultivados na região do Baixo São Francisco é diversificada e com a carga parasitária dependente da qualidade de água e do estágio de desenvolvimento dos peixes.(AU)

This study investigated the parasitic fauna of tambaquis reared in lower Sao Francisco region-Al/SE-Brazil correlating parasitic indices to abiotic and biotic factors. A total of 252 specimens of tambaqui were collected in ten fish farms for parasitological analysis. The parasites were counted, identified and the parasitological indices were determined and correlated to biotic and abiotic factors. Of all collected fish, 65,5 % were parasitized by at least one taxon. Ten taxa were found: Monogeneans, Ichthyophthirius multifiliis, trichodinids Piscinoodinium pillulare, Ichthyobodo sp, Dolops carvalhoi, Lernaea cyprinacea, Procamallanus (Spirocamallanus) inopinatus, Henneguya sp. and Myxobolus sp. The higher prevalences were found to monogeneans (49.2%) and Myxobolus sp. (31.5%). Negative correlation of prevalence and biotic factor (weight and length) were observed to monogeneans (r 2 = -0.49, r 2 = -0.43), Myxobolus sp (r²= -0.46; r²= -0.39) and Henneguya sp (r²= -0.41; r²= -0.39). Abiotic factor of temperature presented a negative correlation to prevalence of Lernaea cyprinacea and trichodinids (r= -0.39 e r= -0.33, respectively) and the electric conductivity presented positive correlation to trichodinids (r= 0.40). It was concluded that parasitic fauna of tambaquis cultured in Lower São Francisco region is diversified and the parasitic load dependent on water parameters and fish growth.(AU)

Efficacy of Ocimum gratissimum essential oil against the monogenean Cichlidogyrus tilapiae gill parasite of Nile tilapia / Eficácia do óleo essencial de Ocimum gratissimum contra o monogenea Cichlidogyrus tilapiae parasita de brânquias de tilápia-do-nilo

The phythotherapy is an alternative to use of chemotherapeutical agents against monogenean infection. This study evaluated the anthelmintic activity of essential oil Ocimum gratissimum against monogenean Cichlidogyrus tilapiae as well as its acute toxicity in tilapia juveniles. The mean lethal concentration (LC50) and different concentrations of the essential oil, both in vitro and in vivo assays (short and long-term baths) were assessed. The LC50 was 40.70mg.L-1 and in the in vitro assay this concentration showed 80% efficacy at the last two hours and in the in vivo assay 65.87% efficacy in long-term bath. However, it provoked morphological alterations on the gills such as hyperplasia and edema. The parasites exposure at the highest concentration (320mg.L-1) showed 100% mortality after 2h exposure in the in vitro assay, whereas in the in vivo assay, short-term baths of 5min for 3 consecutive days showed an efficacy of 87.71% without gills damage. These results demonstrate the anthelminthic activity of essential oil O. gratissimum and the safety concentration to use in Nile tilapia.(AU)

A fitoterapia é uma alternativa ao uso de agentes químicos contra infecções por parasitos monogenéticos. Este estudo avaliou a atividade anti-helmíntica do óleo essencial Ocimum gratissimum contra o monogenea Cichlidogyrus tilapiae , bem como sua toxicidade aguda e histopatologia em juvenis de tilápias. Foram avaliadas a concentração letal média (CL50) e diferentes concentrações de óleo essencial, tanto in vitro como in vivo (banho de curta e longa duração). A CL50 foi de 40,70mg.L-1; no ensaio in vitro, essa concentração apresentou 80% de eficácia, e no ensaio in vivo 65,87% de eficácia em banho de exposição crônica. No entanto, provocou alterações morfológicas nas brânquias, como hiperplasia e edema. A exposição dos parasitas na concentração mais elevada (320mg.L-1) mostrou 100% de mortalidade após duas horas de exposição no ensaio in vitro, enquanto no ensaio in vivo, em banho de curta duração de cinco minutos, durante três dias consecutivos, apresentou uma eficácia de 87,71%, sem danos às brânquias. Esses resultados demonstraram a atividade anti-helmíntica do óleo essencial de O. gratissimum e a concentração de segurança para uso na tilápia-do-nilo em banhos de curta duração.(AU)

Atividade antimicrobiana do óleo essencial de rizomas de açafrão (Curcuma longa L. ) e gengibre (Zingiber officinale Roscoe) frente a salmonelas entéricas isoladas de frango resfriado / Antimicrobial activity of essential oil from Curcuma longa and Zingiber officinale rhizomes against enteric Salmonella isolated from chicken

Objetivou-se com este trabalho identificar, quantificar os constituintes, e avaliar a atividade antibacteriana dos óleos essenciais extraídos de rizomas de açafrão (Curcuma longa L.) e gengibre (Zingiber officinale Roscoe) cultivados nas condições de Manaus/AM frente a 14 salmonelas entéricas isoladas de frango resfriado. A extração dos óleos essenciais foi realizada utilizando-se aparelho tipo Clevenger e a composição determinada por Cromatografia Gasosa acoplada a Espectrometria de Massas (CG-MS). A atividade antibacteriana foi realizada com o emprego de técnica de microdiluição em caldo. O óleo essencial de gengibre se mostrou expressivamente mais eficiente do que o óleo de açafrão, tanto em termos de ação bacteriostática (concentração inibitória mínima de 2500 a 5000 µg.mL-1) quanto bactericida (concentração bactericida mínima de 5000 a 10000 µg.mL-1) observando-se variação apenas em duas as amostras em termos de resistência a ação bactericida deste óleo. Assim, o óleo essencial de gengibre, representa uma alternativa para o controle de Salmonella enterica, entretanto, demais estudos abordando o sinergismo com alimentos são indicados.

The objective of this work was to identify, quantify constituents and evaluate the antibacterial activity of essential oils from rhizomes of turmeric (Curcuma longa L.) and ginger (Zingiber officinale Roscoe) grown under conditions of Manaus/AM front of enteric salmonella isolated from chilled poultry. The extraction of essential oils was performed using the Clevenger type apparatus and composition determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The antibacterial activity was performed with the use of microdilution broth. The essential oil of ginger proved significantly more efficient than tumeric oil, both in terms of bacteriostatic action (minimum inhibitory concentration 2500-5000 mg µg mL-1) and bactericidal (minimum bactericidal concentration 5000-10000 mg µg mL-1) observing changes in only two samples in terms of resistance to bactericidal activity of this oil. Thus, the essential oil of ginger, is an alternative for the control of Salmonella enterica, however, other studies addressing the synergism with food are indicated.

Uso do probiótico Efinol®L durante o transporte de tambaqui (Colossoma macropomum) / The use of probiotic Efinol®L during transportation of tambaqui (Colossoma macropomum)

Verificou-se a eficácia da adição de um probiótico potencialmente redutor de estresse, durante o transporte de juvenis de tambaqui (Colossoma macropomum). Os peixes foram transportados em sacos plásticos com probiótico (20mg/L) ou sem adição do produto à água. O transporte teve duração de 16 horas. Após o transporte, os peixes foram colocados em caixas de 150L para monitorar a recuperação por 96 horas. Para o monitoramento do estresse, avaliaram-se a glicose, o hematócrito e a hemoglobina, além das características de qualidade da água. Após o transporte, a glicose aumentou significativamente, permaneceu elevada nas amostras por 24 e 48 horas e retornou à concentração inicial, 96 horas depois, em ambos os tratamentos. A hemoglobina não se alterou durante e após o transporte, e o hematócrito aumentou significativamente no tratamento sem probiótico nos tempos 24 e 48 horas após o transporte. O probiótico utilizado não foi eficiente em suprimir as respostas de estresse em tambaqui durante o transporte, porém foi eficiente em suprimir as respostas pós-transporte.

The effectiveness of the addition of a potentially stress reducing probiotic during transportation of tambaqui juveniles was studied. Fish were transported with (20mg/L) and without probiotic in the water. The transport duration was 16 hours. After transportation, fish were placed in 150L tanks to monitor their recovery for 96-hours. The following stress parameters were evaluated: glucose, hematocrit, and hemoglobin, and also some water quality parameters. The responses of glucose presented similar pattern between the treatments. Glucose concentrations significantly increased after transportation, kept high for 24 and 48-hours after transportation, and returned to control-like concentration at 96-hours after transportation. Hemoglobin did not present significant difference during or after transportation. Hematocrit significantly increased in probiotic-free treatment at 24 and 48 hours after transportation. The stress response in tambaqui was similar between the tested treatments, indicating that the used probiotic was not efficient in suppressing the stress during transportation; however, it was able to mitigate post-transportation stress response.