BACKGROUND The European chemicals' legislation REACH aims to protect man and the environment from substances of very high concern (SVHC). Chemicals like endocrine disruptors (EDs) may be subject to authorization. Identification of (potential) EDs with regard to the environment is limited because specific experimental assessments are not standard requirements under REACH. Evidence is based on a ...

Growth and reproduction in marine fish populations can be strongly influenced by local habitat quality nutritional resources. Habitat degradation alter prey composition availability, and, consequently, trophic position dietary niche breadth of fish. In the present study, we compared length-frequency distributions, growth, stomach contents, isotopic values (δ 13 C δ 15 N) blue cod Parapercis col...

Four biological aspects of Schizodon nasutus in the low Sorocaba river basin, São Paulo, Brazil were analysed. These were accomplished during the year seasons. The fish diet and the feeding activity were investigated by studying the repletion index, which showed no significant differences between seasons. The food items analysed by frequency of occurrence and dominance showed a predominance of ...

Dissolved Oxygen (DO) is one of the most important factors for aquatic animals as especially those who derive dissolved oxygen from water. DO levels indicate quality Many biotic and abiotic may influence concentration like mixing different water bodies, upwelling, atmospheric exchange, respiration, photosynthesis, ice cover, pollution some physical salinity temperature. The fluctuations in affe...

Host fish acquire immunity to the parasitic larvae (glochidia) of freshwater mussels (Unionidae). We investigated the persistence of acquired immunity of largemouth bass, Micropterus salmoides (Lacepède, 1802) to glochidia of the broken rays mussel, Lampsilis reeveiana (Call, 1887). Fish received 3 successive priming infections with glochidia to induce an immune response. Primed fish were held ...

Optimal control theory is applied to a system of ordinary differential equations modeling Buruli ulcer transmission in population. We apply controls on mass treatment, insecticide and mass education to minimize the number of infected hosts and infected vectors as well as infected fishes. The model takes into account human, water bug and fish populations as well as MU in the environment. The hos...

A prominent feature of comparative life histories in fish (and other indeterminate growers) is the approximate invariance across species of certain dimensionless numbers made up from reproductive and timing variables. The two best known are the age at maturity (alpha) divided by the average adult lifespan (E), and the proportion of a body mass given to reproduction per year (c) multiplied by E....

Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that belongs to the RFamide peptide family and was first identified in the quail brain. From the discovery of avian GnIH, orthologous GnIH peptides have been reported in a variety of vertebrates, including mammals, amphibians, teleosts and agnathans, but also in protochordates. It has been clearly established that GnIH suppre...

Oryzias latipes (Adrianichthyidae), known as Japanese medaka or Japanese killifish, is a small 2-4 cm long fish common in rice paddies in coastal Southeast Asia and is also a popular aquarium fish. It has been widely used as a research model because of its small size and because it is very easy to rear. Alkalinity stress is considered to be one of the major stressors on fish in saline-alk...