Perfil microbiológico de peixes e água de cultivo em pesque-pagues situados na região nordeste do estado de São Paulo / Microbiological profile of fish and pond water in fee-fishing located in the northeast region of São Paulo state, Brazil

O objetivo deste trabalho foi determinar o número de coliformes totais, termotolerantes, Staphylococcus coagulase positivo e a presença de bactéria do gênero Salmonella no músculo, no tecido superficial, no trato gastrintestinal de peixes e na água de cultivo de pesque-pagues situados na microbacia do Córrego Rico, SP. Não foi detectado Staphylococcus coagulase positivo em nenhuma amostra de água e peixe. O número mais provável (NMP) de coliformes totais no peixe variou de 2,0 x 10 a >1,1 x 104 NMP.100 mL-1, na água de cultivo variou de 4,2 x 104 a > 2,4 x 105 NMP.100 mL-1. A contagem de coliformes termotolerantes no peixe variou de < 3 a 5,1 x 103 NMP.g-1, na água de cultivo variou de 3,8 x 102 a 2,0 x 104 NMP.100 mL-1. Não houve diferença estatística (P > 0,05) entre as populações de micro-organismos pesquisados na água, pele e trato gastrintestinal, o que reflete uma relação entre a presença dos micro-organismos na água e nesses dois locais analisados. Foi isolada Salmonella sp. em uma amostra de músculo e em duas amostras de trato gastrintestinal. O pescado pode ser veículo de contaminação cruzada, tendo como fonte dos micro-organismos a pele e o trato gastrintestinal para sua própria musculatura. Portanto, o monitoramento da qualidade da água é de suma importância para garantir a produção de peixes com boa qualidade.

The objective of this study was to determine the number of total and thermotolerant coliforms, coagulase-positive Staphylococcus, and the presence of bacteria of the genus Salmonella in the muscle, surface tissue, and gastrointestinal tract of fish, and in the pond water of fee-fishing establishments located in the Córrego Rico microwatershed in the state of São Paulo, Brazil. Coagulase-positive Staphylococcus was not detected in any sample of pond water or fish. The most probable number (MPN) of total coliforms in fish ranged from 2.0 x 10 to > 1.1 x 104 NMP.100 mL-1, while in pond water it ranged from 4.2 x 104 to > 2.4 x 105 NMP.100 mL-1. The count of thermotolerant coliforms in fish ranged from < 3 to 5.1 x 103 NMP.g-1, while in pond water it ranged from 3.8 x 102 to 2.0 x 104 NMP.100 mL-1. There was no statistical difference (P > 0.05) among the studied populations of microorganisms in pond water, surface tissue and gastrointestinal tract, which reflects a relationship between the presence of microorganisms in the water and in the two tissues analyzed. Salmonella sp. was isolated in one sample of muscle and in two samples of gastrointestinal tract. The fish can be a vehicle for cross contamination, having the gastrointestinal tract and the surface tissue as a source of microorganisms for its muscles. Therefore, monitoring the water quality is important to ensure the production of fish with good quality.

Changes in activity of hepatic xenobiotic-metabolizing enzymes of tiger puffer (Takifugu rubripes) exposed to paralytic shellfish poisoning toxins.

Attempts were made to examine the effect of paralytic shellfish poisoning toxins (PSP) on hepatic xenobiotic-metabolizing enzymes (XMEs) of tiger puffer (Takifugu rubripes). Two groups of nontoxic tiger fish were analyzed, and one group was fed with a PSP-containing diet (PSP group), and another with a PSP-free diet (control group). After 60 days of feeding, they were compared to each other mainly in terms of the activity of XMEs. Both groups did not differ from each other significantly in body weight gain, hepatosomatic index, and condition factor Hepatic level of cytochrome P450 was lower in PSP group than control group. NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, and ethoxyresorufin-O-deethylase (EROD) exhibited a reduced activity in PSP group than control group. Statistical analysis found that the activity or concentration of those enzymes correlated with the hepatic level of PSR with r2=0.497-0.611.