Flora bacteriana de tilápia do Nilo, Oreochromis niloticus, cultivada em sistema semi-intensivo - DOI: 10.4025/actascibiolsci.v25i2.2007

This experiment measured total bacterial numbers in the gastrointestinal regions of semi-intensively cultured tilapia, Oreochromis niloticus L. (Cichlidae). Mean bacterial numbers were higher in both anterior and posterior gut than in stomach. The percentage of isolated species and the percentage of isolates from any particular species varied significantly among gastrointestinal tract regions. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans and Plesiomonas shigelloides were the most frequently isolated Gram-negative bacilli. From these samples, only Plesiomonas shigelloides was present in both gastrointestinal regions, with higher number in the posterior gut (76%), when compared to anterior gut (4.8%) and stomach (0.6%). Aeromonas hydrophila (0.6%), Escherichia coli (7.4%), and Flavimonas oryzihabitans were isolated only in the stomach, and Citrobacter freundii and Burkholderia cepacia were found only in the posterior gut. Chromobacterium violaceum was the dominant bacteria isolated from stomach and anterior gut, with 90% and 55%, respectively. Unidentified organisms comprised 0 - 39.3% of the gastrointestinal microfloraA flora bacteriana de diferentes partes do trato gastrintestinal de tilápia Oreochomis niloticus L. (Cichlidae) foi determinada. O número médio de bactérias foi maior no intestino anterior e posterior quando comparado ao estômago. A porcentagem total de espécies bacterianas isoladas e a porcentagem de espécies isoladas em uma espécie particular variaram significativamente entre as regiões do trato gastrintestinal. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans e Plesiomonas shigelloides foram os bacilos Gram-negativos encontrados com maior freqüência. Destas espécies, somente Plesiomonas shigelloides esteve presente em cada região do trato gastrintestinal, apresentando maior número no intestino posterior (76%), quando comparado com o intestino anterior (4.8%) e o estômago (0.6%). Aeromonas hydrophila (0.6%), Escherichia coli (7.4%), e Flavimonas oryzihabitans foram isoladas somente do estômago, e Citrobacter freundii e Burkholderia cepacia foram encontradas somente no intestino posterior. Chromobacterium violaceum foi a espécie dominante isolada do estômago e do intestino anterior com 90% e 55%, respectivamente. Organismos não identificados compreendem 0 – 39.3% da microbiota gastrintestina

Valores hematológicos e bioquímicos em tilápia do Nilo Oreochromis niloticus cultivada em sistema semi-intensivo - DOI: 10.4025/actascibiolsci.v25i2.2028

The aim of the present study was to investigate the reference ranges for haematological and biochemical values for Nile tilapia, Oreochromis niloticus (Cichlidae), cultivated in a semi-intensive system. Erythrocytes number was 6.93 ± 8.28 x 106/mm3, hemoglobin 10.52 ± 3.09g/dL of blood and hematocrit 31.85 ± 8.45%, mean corpuscular volume (MVC) 148.80 ±. 153.19µ3, mean corpuscular hemoglobin (MCH) 40.74 ± 34.19 pg and mean corpuscular hemoglobin concentration (MCHC) 35.24 ± 14.92%. Total plasma protein and glucose values obtained were 3.06 ± 0.65g/dl and 60.32 ± 20.22mg/dl, respectively. A correlation matrix was established to compare de degree of association among biometric data and hematological parameters, and among each of them and biochemical values. A positive correlation was observed among weight, length, MCV and MHC, as well as between length and hematocrit. The blood glucose level was positively correlated with weight and length, whereas total protein was positively correlated with hemoglobin. The erythrocytes count was positively correlated with hemoglobin and negatively correlated with MCV and MHC. Microscopy examination of blood smears revealed the presence of erythrocytes, neutrophils, lymphocytes, and monocytes. Under the conditions employed here, no basophils or eosinophils, nor their precursors, could be found in blood smears of Nile tilapiaO objetivo do presente estudo foi investigar os valores de referências hematológicos e bioquímicos para a tilápia do Nilo, Oreochromis niloticus (Cichlidae), cultivada em sistema semi-intensivo. A contagem de eritrócitos foi 6,93 ± 8,28 x 106/mm3, hemoglobina 10,52 ± 3,09g/dL de sangue, hematócrito 31,85 ± 8,45%, volume corpuscular médio (MVC) 148,80 ±.153,19µ3, hemoglobina corpuscular média (MCH) 40,74 ± 34,19pg e concentração de hemoglobina corpuscular média 35,24 ± 14,92%. Os valores de proteína plasmática total e da glicose obtidos foram de 3,06 ± 0,65g/dl e 60,32 ± 20,22mg/dl, respectivamente. Uma matriz de correlação foi estabelecida para comparar o grau de associação entre os dados biométricos e parâmetros hematológicos, e entre estes e os valores bioquímicos. Uma correlação positiva foi observada entre peso, comprimento, MCV e MHC, bem como entre comprimento e hematócrito. O nível de glicose sanguínea foi positivamente correlacionado com o peso e o comprimento, enquanto proteína total foi positivamente correlacionada com a hemoglobina. A contagem de eritrócito foi positivamente correlacionada com a hemoglobina e negativamente correlacionada com MCH e MHC. A observação microscópica do esfregaço sangüíneo revelou a presença de eritrócitos, neutrófilos, linfócitos e monócitos. Sob as condições empregadas no estudo não foram encontrados basófilos, ensinófilos ou seus precursores no esfregaço sangüíneo de tilápia do Nil

Programa de Pós-graduação em Microbiologia, Universidade Estadual de Londrina.

ABSTRACT. This experiment measured total bacterial numbers in the gastrointestinal regions of semi-intensively cultured tilapia, Oreochromis niloticus L. (Cichlidae). Mean bacterial numbers were higher in both anterior and posterior gut than in stomach. The percentage of isolated species and the percentage of isolates from any particular species varied significantly among gastrointestinal tract regions. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans and Plesiomonas shigelloides were the most frequently isolated Gramnegative bacilli. From these samples, only Plesiomonas shigelloides was present in both gastrointestinal regions, with higher number in the posterior gut (76%), when compared to anterior gut (4.8%) and stomach (0.6%). Aeromonas hydrophila (0.6%), Escherichia coli (7.4%), and Flavimonas oryzihabitans were isolated only in the stomach, and Citrobacter freundii and Burkholderia cepacia were found only in the posterior gut. Chromobacterium violaceum was the dominant bacteria isolated from stomach and anterior gut, with 90 % and 55%, respectively. Unidentified organisms comprised 0- 39.3 % of the gastrointestinal microflora. Key words: tilapia, bacterial flora, gastrointestinal tract, Oreochromis niloticu

Trypanosoma cruzi: genetic group with peculiar biochemical and biological behavior

Thirty-two Trypanosoma cruzi strains, isolated from chronic chagasic patients in the northwest of the state of Paraná (Brazil), were analyzed using molecular, biochemical and biological characteristics. Genotypic analysis using randomly amplified polymorphic DNA and simple sequence repeat-anchored polymerase chain reaction amplified profiles showed a large, genetically well-correlated group that contained the majority of the strains and a divergent group that included the PR-150 strain. For glycoconjugate composition, the PR-150 strain was different from the other strains considering the absence or presence of specific bands in aqueous or detergent phases. This strain was also totally different from the others in one out of the six parameters related to in vitro and in vivo biological behavior. We highlight the fact that the PR-150 was totally resistant to benznidazole. For the other biological parameters this strain was not totally distinct from the others, but it showed a peculiar behavior