Light microscopy and ultrastructure of the liver of Astyanax altiparanae Garutti and Britski, 2000 (Teleostei, Characidae).

Livers of thirty specimens of Astyanax altiparanae obtained from a commercial fish farm were subjected to light and transmission electron microscopy, in order to describe the hepatic parenchyma and the intrahepatic exocrine pancreatic tissue. Anatomically, the liver showed only three hepatic lobes. Histological analysis demonstrated that the hepatocytes were spread out as anastomotic cords, arranged in two cellular layers and surrounded by sinusoids. The intrahepatic exocrine pancreatic tissue exhibited an acinar arrangement and was diffused in the hepatic parenchyma. Ultrastructural analysis showed that the hepatocytes had a rounded nucleus and a rough endoplasmatic reticulum, with a parallel disposition to the nuclear membrane. The exocrine pancreatic cells showed secretion granules at the apical portion, and the rough endosplasmatic reticulum was concentrically distributed.

Mercury in soils and sediments from gold mining liabilities in Southern Amazonia

The 1980-1990 Amazonian gold rush left an enormous liability that increasingly has been substituted by developing fish aquaculture. This work aimed at the identification of the mercury levels in the environment, associated with fish farms located in the North of Mato Grosso State, Southern Amazon. Sediment and soil samples were analyzed for total organic carbon and total mercury. Results indicate that the chemical characteristics of the sediment largely depend on the management procedures of the fish pond (liming, fish food used and fish population). The soils presented relatively low concentrations when compared with other data from the literature.

Leukocyte and thrombocyte reference values for channel catfish (Ictalurus punctatus Raf), with an assessment of morphologic, cytochemical, and ultrastructural features

Background: Hematology tests are useful to evaluate physiologic disturbances in fish and can provide important information for the diagnosis and prognosis of disease. Objectives: the primary purpose of this study was to define reference intervals for thrombocytes and leukocytes in healthy channel catfish (Ictalurus punctactus). In addition, the morphologic, cytochernical, and ultrastructural features of blood cells were assessed. Methods: Blood samples (0.5 mL were collected into EDTA from 40 clinically healthy catfish on a commercial fish farm in Jaboticabal, Brazil. Thrombocyte, total WBC, and differential WBC counts were determined and reference intervals were calculated as the 25-95th percentiles of data. Thrombocyte and leukocyte morphology was assessed in blood smears stained with May Griinwald-Giemsa-Wright and ultrastructurally by transmission electron microscopy. Cytochemical staining patterns were described using periodic acid-Schiff (PAS), peroxidase, nonspecific esterase, alkaline phosphatase, and toluidine blue. Results: Reference intervals were as follows: thrombocytes 58,802-99,569/mu L; total WBCs 27,460-41,523/mu L; lymphocytes 5380-11,581/mu L; monocytes 2949-7459/mu L; neutrophils 12,529-22,748/mu L, and basophils 736-2003/mu L. Neutrophils were positive for peroxidase and PAS; monocytes were positive for nonspecific esterase; and basophils were positive with toluidine blue. Conclusion: the morphologic and staining features of neutrophils and monocytes of channel catfish are similar to those of mammals, and the presence of basophils in this species was verified. These reference intervals and morphologic findings provide a foundation for future investigations on the functions and alterations of blood cells in channel catfish.

Sistema orgânico de produção de pescado de água doce

This study aimed to collect data about organic production of freshwater fish. Today the production of organic food of plant origin is predominant in the market, however, the animal rearing with organic certificate has great potential, and is an important tool for adding value to grains and organic products. Regarding the regulation of organic aquaculture, producers are based on international standards. In Brazil, the norms for breeding are very recent and their regulation was consolidated through Interministerial Instruction No28, published on June 8, 2001 by Ministério da Agricultura, Pecuária e Abastecimento (MAPA) together with Ministério da Pesca e Aquicultura (MPA). In the literature there are few studies with organic fish farm, but according to available data, the rearing of species such as tilapia (Oreochromis niloticus), pacu (Piaractus mesopotamicus) and jundia (Ramdhia sp) fed with organic diet, in different rearing systems, show results quite optimistic about the production system, which is the focus of this work.

Piscicultura e manejo da qualidade da água

Fish farms' water quality management is analyzed with regard to the management employed and the different trophic states are compared within the system during the dry and rainy seasons. Six sites were marked two in the water supply (P1 and P2), and four within the fish farm (P3 to P6). Whereas sites P1 and P2 (water supply) were characterized as oligotrophic, the others were mesotrophic and eutrotrophic sites. Environmental variables, mainly nutrients, conductivity, COD, BOD5 and TSS tended to increase as from P3 due to management and fertilization. Greater impact has been registered in the fish farm under analysis for variables COD, ammonia, total phosphorus and TSS during the discharge and pond emptying period. Frequent monitoring of water quality should be undertaken in fish breeding and plankton production ponds, especially in those close to P3 and P4. Removal of sediment in decantation lake or P5 is also recommended to decrease nutrient concentrations, especially phosphorus, accumulated on the bottom soil.

Frequência de arraçoamento para alevinos de carpa comum

The best frequency of feeding for development of common carp fingerlings Cyprinus carpio was determined. Four hundred fish (4.88 ± 1.41 g and 6.72 ± 0.70 cm) were used, distributed in 20 tanks of 250 L each in completely randomized design with four treatments and five replicates. The four feeding strategies adopted were: providing feed once (T1), twice (T2), three (T3) and four times daily (T4) at the same amount being fractionated as described. At the end of 45 days of experiment were carried out measurements of the final weight (FW), final length (FL), weight gain (WG), feed conversion (FC), specific growth rate (SGR) and survivor (SR). It was evaluated the chemical composition of fish carcass: moisture (MT), crude protein (CP), lipids (LP) and ash (AS) and hematological analyzes performed such as erythrocyte (ER), hemoglobin (HG) and hematocrit (HT). There were significant statistical differences (P<0.01) for FW, FL, WG and SGR. For FC and SR there were no statistical differences (P>0.01). For the chemical composition the moisture, lipids and ash showed significant statistical differences (P>0.01), except only for protein (P>0.01) The hematological composition was not influenced by the feed frequency, it was not observed significant statistical difference (P>0.01) of erythrocytes, hemoglobin and hematocrit among dietary treatments. For common carp fingerlings, the provision of ration four times daily provided better final weight, final length, weight gain and specific growth rate without causing changes in the composition and hematological parameters of the fish.

Efeito de dietas e altura da coluna d’água na sobrevivência de larvas de Betta splendens e o aporte de nitrogênio e fósforo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade microbiológica do ambiente e da tilápia-do-Nilo (Oreochromis niloticus) produzida em sistema de tanques-rede no reservatório de Chavantes, SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ecotoxicidade e eficácia de sanitizante na redução de Aeromonas hydrophila na água de cultivo e pele de Oreochromus niloticus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diversidade bacteriana em piscicultura neotropical

Pós-graduação em Microbiologia Agropecuária - FCAV

Infecções parasitárias e microbianas na produção do pacu Piaractus mesopotamicus e do híbrido patinga procedentes da região noroeste do Estado de São Paulo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características limnológicas em áreas sob influência de piscicultura em tanques-rede no reservatório da UHE Chavantes, rio Paranapanema, SE/S, Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Suplementação alimentar com 'beta'-glucano e mananoligossacarídeo para tilápias do Nilo em tanques-rede

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bactérias do gênero Aeromonas e indicadores de qualidade da água em pisciculturas da Região da Baixada Ocidental Maranhense

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variação da comunidade planctônica e fatores físico-químicos da água em dois sistemas de aquicultura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)