Polyculture of Freshwater Angelfish Pterophyllum scalare and Pacific white shrimp Litopenaeus vannamei in low-salinity water

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Suplementação de vitamina A em dietas para Kinguios (Carassius auratus)

Vitamin A is important to the proper development and functioning of the body, appearing in several metabolic functions. This experiment was conducted with aim evaluate to the vitamin A supplementation in diets for Goldfish Carassius auratus. The experimental was completely randomized with six treatments (0, 2.000, 4.000, 8.000, 16.000 and 32.000 IU of vitamin A kg(-1) diet) with four repetitions into 24 experimental cages, with capacity for 150 liters useful volume, made of mesh shading, installed inside a masonry circular tank with a capacity of 25 m(3) of water. 192 fish with an average initial weight of 6.66 +/- 0.57 g and initial length of 7.30 +/- 0.33 cm, feed at 8h, 11h, 14h and 17h at satiety were used. Evaluated the effects on productive performance and intensity of yellow-red coloring of the skin of the fish were. The Linear Response Plateau analysis of weight gain and length total, feed conversion and daily growth rate versus vitamin A requirement estimate showed 2,624, 2,385 and 2,358, 4,381 and 2,866 IU of vitamin A per kg diet, respectively. The data indicated that this vitamin has little or no influence on the intensity of the skin color of the Goldfish.

Effect of beta 1,3 glucan in stress responses of the pencilfish (Nannostomus trifasciatus) during transport within the rio Negro basin

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

Oogenesis in Laetacara araguaiae (Ottoni and Costa, 2009) (Labriformes: Cichlidae)

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

Ultraestrutura e citoquímica do tubo digestivo de Hemisorubim platyrhynchos (Teleostei, Siluriformes, Pimelodidae)

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

Whole-body cortisol increases after direct and visual contact with a predator in zebrafish, Danio rerio

Ornamental fish may be severely affected by a stressful environment. Stressors impair the immune response, reproduction and growth rate; thus, the identification of possible stressors will aid to improve the overall quality of ornamental fish. The aim of this study was to determine whole-body cortisol of adult zebrafish, Danio rerio, following visual or direct contact with a predator species. Zebrafish were distributed in three groups: the first group, which consisted of zebrafish reared completely isolated of the predator, was considered the negative control; the second group, in which the predator, Parachromis managuensis was stocked together with zebrafish, was considered the positive control; the third group consisted of zebrafish stocked in a glass aquarium, with direct visual contact with the predator. The mean whole-body cortisol concentration in zebrafish from the negative control was 6.78 +/- 1.12 ng g(-1), a concentration statistically lower than that found in zebrafish having visual contact with the predator (9.26 +/- 0.88 ng g(-1)) which, in turn, was statistically lower than the mean whole-body cortisol of the positive control group (12.35 +/- 1.59 ng g(-1)). The higher whole-body cortisol concentration found in fish from the positive control can be attributed to the detection, by the zebrafish, of relevant risk situations that may involve a combination of chemical, olfactory and visual cues. One of the functions of elevated cortisol is to mobilize energy from body resources to cope with stress. The elevation of whole-body cortisol in fish subjected to visual contact with the predator involves only the visual cue in the recognition of predation risk. We hypothesized that the zebrafish could recognize predator characteristics in P managuensis, such as length, shape, color and behavior. Nonetheless, the elevation of whole-body cortisol in zebrafish suggested that the visual contact of the predator may elicit a stress response in prey fish. This assertion has a strong practical application concerning the species distribution in ornamental fish markets in which prey species should not be allowed to see predator species. Minimizing visual contact between prey and predator fish may improve the quality, viability and welfare of small fish in ornamental fish markets. (c) 2007 Elsevier B.V. All rights reserved.

Efeito do tipo de alimento no desempenho produtivo de juvenis de acará-bandeira (Pterophyllum scalare)

This study aimed to evaluate the effect of food type on growth performance and water quality of angelfish juvenile. A total of 168 angelfish Pterophyllum scalare var. marble (w(i) = 151.3 +/- 37.9 mg e l(i) = 2.2 +/- 0.07 cm) were distributed in 12 aquaria 14 L (1.0 fish L(-1)). The experiment was conducted in a complete randomized design with three treatments and four replicates. Foods evaluated were: Artemia nauplii, commercial flakes diet and commercial powder diet. Fish weight and length were recorded in the beginning and the end of 60 experimental days. Water temperature, dissolved oxygen, pH and total ammonia were monitored during experiment. Best averages of final weight, final length, weight gain and condition factor were observed on fish fed powder diet. Specific growth rate, weight uniformity and survival were not influenced (p > 0.05) by food type. Just on length uniformity fish fed Artemia showed better averages than fish fed flakes diet and powder diet. Foods evaluated did not influenced (p > 0.05) on water quality parameters. In conclusion, for juvenile angelfish, the food type influences growth performance without affect water quality parameters. Powder diet resulted in better growth performance.

Protozoan parasites of Xiphophorus spp. (Poeciliidae) and their relation with water characteristics

Investigou-se a relação entre as características da água e a infestação de protozoários parasitos, Icthyophthirius multifiliis e Trichodina sp., em peixe espada, Xiphophorus helleri e em plati, Xiphophorus maculatus, coletados em uma piscicultura de peixes ornamentais no Estado de São Paulo, Brasil. Os peixes foram coletados mensalmente, durante um ano, dos viveiros e das caixas de estocagem. A prevalência da infestação nos peixes das caixas e dos viveiros foram, respectivamente, 34,2% e 22,5% para I. multifiliis e 13% e 54% para Trichodina sp. A elevada condutividade elétrica e o pH da água reduziram a infestação por I. multifiliis. A baixa concentração de oxigênio resultou em aumento na infestação por Trichodina sp. O uso do sal, para aumentar a condutividade elétrica da água, consistiu em um método de controle de I. multifiliis. A redução do oxigênio dissolvido e a adição de fertilizante orgânico favoreceram a reprodução de Trichodina sp.

Feeding level and frequency for freshwater angelfish

The objective of this study was to determine the optimal feeding level and feeding frequency for the culture of freshwater angelfish (Pterophyllum scalare). A randomized block design in a factorial scheme (3 × 2) with three feeding levels (30, 60 and 90 g/kg of body weight (BW)/day) and two feeding frequencies (1x and 2x/day) was set up in duplicate, representing 24 experimental units. Data were analyzed using two-way ANOVA and the Tukey test for comparison between means. After 84 days, results indicated that both factors influenced fish performance. No interaction between these factors was, however, observed. Increased feeding level and feeding frequency resulted in increased feed intake. The feed conversion ratio was negatively affected by feeding level, but not affected by feeding frequency. Final weights were higher when fish were fed twice daily, at levels of 60 or 90 g/kg BW/day. Specific growth rate was higher when fish received 60 or 90 g/kg BW/day, regardless of the feeding frequency. Survival was not affected by any treatment, with mean survival rates higher than 90%. It is recommended that juveniles be fed at a level of 60 g/kg BW/day with a minimum of two meals per day, to attain optimal survival, growth and feed efficiency.

Densidade de estocagem para produção de Acará-bandeira em viveiros escavados em policultivo com Camarão-da-amazônia

The aim of this study was to evaluate the production of Freshwater Angelfish (Pterophyllum scalare) in different stocking densities in cages polycultured with Amazon River Prawn (Macrobrachium amazonicum). Four treatments were evaluated (1; 2; 3 and 4 fish. 10 L(-1)) using two ponds and 24 experimental units. Water quality parameter reached adequate levels for the species. Production data were submitted to ANOVA. Fish produced in the lowest density showed higher values of final weight and standard length, and lower total biomass in comparison with the others treatments. Feed conversion rate, survival, batch uniformity and body factor were not significant different among treatments. The highest density tested produced more fish and gross yield than the others treatments. The density 20 fish. 10L(-1) is recommended to produce Freshwater Angelfish in cages polycultured with Amazon River Prawn.

Genetic structure of the ornamental tetra fish species Piabucus melanostomus Holmberg, 1891 (CHARACIDAE, IGUANODECTINAE) in the Brazilian Pantanal wetlands inferred by mitochondrial DNA sequences

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

Cytogenetic characterisation of the ornamental freshwater fish, Piabucus melanostomus (Iguanodectinae) from Brazilian wetlands and its relation with species of Characidae basal group

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Conservation and sustainable utilization of Nigerian ornamental fishes

The paper assessed qualitatively the threat status of nigerian freshwater fishes that are presently being exported and those that have potential in aquarium trade using such criteria as rarity, size at maturity, mode of reproduction, human population density, habitat degradation, pollution and range of each species among others. For their conservation captive breeding of these fishes were proffered with information that can assist collectors, exporter and aquaculturists that wants to breed polypterids, Butterfly fish, Knife fish, Elephantfish, Pollymyrus isidori, Arnordichthys spilopterus, Nannaethiops unitaeniatus, Killifishes, Polycentropsis abbreviatta, Cichlids, Ctenpomas, Mastacembelids and Tetraodon lineatus

Export potential of ornamental live fishes in Nigeria

Nigeria is blessed with an abundant variety of fish species, some of which have been exported over the years. These fish species are taken either from the wild or cultured. Large quantities of fishes and fishery products are exported from Nigeria in different forms and which have been sources of foreign exchange earnings for the Country. An estimate value of exports in the fishery sub-sector stood at approximately U.S. $48.212,070 for shrimps/sole fish/cuttlefish/crabs and over U.S.$500,000 for ornamental live fishes

Low cost light traps for coral reef fishery research and sustainable ornamental fisheries

Two relatively inexpensive light traps to capture pre-settling reef fish and invertebrates are described. A trap made from a plastic bucket (with plastic bottles, a small plastic waste bin and two sheets of plywood) that costs US$15 appears to be just as effective as a large aluminium and plexiglass trap that costs US$275.