RESUMO
Downstream migration of young coho salmon in the northern part of the range is observed at different ontogenetic stages. Three migration periods were identified: passive migration of yearlings within the spawning river; migration of parr older than 1 year from the spawning tributary to the main river; and migration of smoltifying fish from the river to the sea. The smoltification and seaward migration of the bulk of young salmons from the Kalkaveem River takes place at the age of 2 years. Mass downstream migration of young coho salmons starts in early June at 9 degrees C. No clear diel pattern was observed in the migration of young coho salmon. The lowest migration activity was observed from sunrise to noon (3:00-12:00) when the feeding activity of young salmons increases.
Assuntos
Oncorhynchus kisutch/fisiologia , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Envelhecimento/fisiologia , Animais , Dinâmica Populacional , Estações do Ano , SibériaRESUMO
Data have been presented on carcinogenic N-nitrosoamines (NA) synthesis from precursors in the gastric juice and in the stomach of rats. It is shown that vegetable juices and milk produce an inhibitory effect with respect to NA synthesis in vitro and in vivo, however, food products with high content of fat intensify amine nitrosation.
Assuntos
Alimentos , Nitrosaminas/metabolismo , Animais , Bebidas , Laticínios , Feminino , Frutas , Suco Gástrico/análise , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Técnicas In Vitro , Masculino , Nitrosaminas/análise , Nitrosação , Ratos , Distribuição Tecidual , VerdurasRESUMO
Data are presented on nitrosamine (NA) formation in the stomach of dogs after per os intake of their precursors--morpholine (or diethylamine) and sodium nitrite. It has been shown that bread enriched with lysine given to dogs in combination with the precursors promotes a five-six-fold reduction of carcinogenic NA formation in the dog's stomach as compared to the control.
Assuntos
Pão , Dietilaminas/farmacocinética , Aditivos Alimentares , Lisina/farmacologia , Morfolinas/farmacocinética , Nitrosaminas/metabolismo , Estômago/efeitos dos fármacos , Animais , Cães , Mucosa Gástrica/metabolismo , Nitrito de Sódio/administração & dosagem , Fatores de TempoRESUMO
The data are presented on the content of nitrosamines in meat products prepared according to traditional technology versus the use of water-soluble vitamins and their complex. It is shown that the enrichment of sausage products and canned meat with thiamine, riboflavin, nicotinamide and ascorbic acid is conducive to better hygienic parameters of the products, with lower content of nitrosamines (from 29.4 to 72.6%) as compared to meat products prepared according to the traditional technology.