Paraquat is a contact and non-selective herbicide which is used for controlling a wide range of terrestrial weeds and aquatic plants. A long-term contact with this xenobiotic can potentially lead to injuries in fishes as live non-target organisms. Therefore, the current study aimed to investigate the effect of sub-lethal toxicity of paraquat on the pathology of gill, liver, and spleen tissues i...

Blue gourami fish have a pair of modified ventral fins that are used to obtain tactile information about surrounding objects. Use of ventral fins by blue gourami was investigated during initial exploration of novel objects. When exposed to a sequence of novel plastic objects, varying in shape and colour, the blue gourami showed preferential use of the left fin during initial contacts. Lateralit...

We examined the relationship between aggression and cerebral lateralization, as expressed by eye-use preference in a mirror-response paradigm, in six species of anabantoid fishes in the teleost family Belontiidae. Our objective was to test the hypothesis that frequency-dependent selection should decrease lateralization at the population level in more aggressive species. The mean laterality inde...

Fishes have evolved a diversity of sound-generating organs and acoustic signals of various temporal and spectral content. Additionally, representatives of many teleost families such as otophysines, anabantoids, mormyrids and holocentrids possess accessory structures that enhance hearing abilities by acoustically coupling air-filled cavities to the inner ear. Contrary to the accessory hearing st...

Macrophage aggregate (MA) morphometry and pigment composition are believed to be dependent on the species, age, and health status of the fish. The aim of this study was to characterize a "normal" morphometry baseline of spleen and kidney MAs in blue gourami Trichogaster trichopterus and freshwater angelfish Pterophyllum scalare. Three size-classes of clinically normal fish were analyzed. Blue g...

In this study, the GH and IGF-I of blue gourami (Trichogaster trichopterus) were examined at different temperatures of 23 ο C, 27 ο C and 31 ο C. GH mRNA expression in the pituitary of males and females at various temperatures was examined using RT-PCR. The mean of mRNA levels was higher in the pituitary glands of females maintained in 23 ο C and 27 ο C than in males. However, no significant di...

aPrograma de Pós-graduação em Ecologia, Instituto Nacional de Pesquisas da Amazônia – INPA, Avenida André Araújo, 2936, CEP 69060-001, Amazonas, AM, Brazil bInstituto de Ciências do Mar – LABOMAR, Universidade Federal do Ceará – UFC, Avenida Abolição, 3207, CEP 60165-081, Fortaleza, CE, Brazil cDepartamento de Biologia, Universidade Federal do Ceará – UFC, Campus do Pici, Avenida Mister Hull, 2...