Artemia sp. na alimentação de larvas de jundiá (Rhamdia quelen)

A considerable problem in the catfish larvae rearing is related to the first feeding. This study aimed to determine the larvae growth and the survival of silver catfish submitted to feeding with Artemia sp. in different time periods. The study was conducted in the Aquaculture Laboratory of the Universidade Estadual do Oeste do Paraná, with four treatments and five replications, constituted by feeding with Artemia sp. in 5, 10, 15 and 20 days, and after each period of time, by its replacement by ration. We used 200 larvae distributed into 20 aquariums, soon after the eggs hatched. The larvae were fed 4 times a day until apparent satiation for 30 days. The Artemia sp. feeding for 15 days provided the best results on weight gain, final length and survival.

Juvenile development of the crab Bathyrhombila sp (Crustacea, Decapoda, Pseudorhombilidae) from megalopae obtained in the neuston

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

Desenvolvimento juvenil do caranguejo Bathyrhombila sp. (Crustacea, Decapoda, Pseudorhombilidae), a partir de megalopas obtidas no nêuston

O reconhecimento de braquiúros jovens, obtidos na natureza, é extremamente difícil, pois nesta fase os caranguejos não apresentam as mesmas características dos adultos. Além disso, há falta de estudos sobre o desenvolvimento pós-embrionário desses animais. Nada é conhecido sobre o desenvolvimento juvenil para os representantes da família Pseudorhombilidae. Este trabalho analisa o crescimento de Bathyrhombila sp., e apresenta detalhes morfológicos para identificação dos estágios de desenvolvimento. Os decapoditos de braquiúros foram coletados com redes de nêuston na região de Ubatuba, estado de São Paulo, Brasil. As larvas foram transportadas para o laboratório e cultivadas isoladamente em recipientes rotulados, contendo água do mar filtrada e aerada, além de alimentadas com nauplius de Artemia sp. Obteve-se 11 estágios juvenis para machos e 14 para fêmeas. A morfologia e o número de cerdas presentes nos apêndices são descritos, em especial, para o 1º estágio juvenil. Os caracteres sexuais secundários aparecem a partir do 4º estágio juvenil. Uma comparação com as demais espécies de caranguejos já estudadas evidenciou que Bathyrhombila sp. possui a forma da carapaça semelhante à de Eurytium limosum. Além disso, Bathyrhombila sp. possui cinco artículos no endopodito do segundo maxilípede, enquanto as outras espécies de Xanthoidea e Eriphioidea possuem quatro

Growth rate of the crab Dissodactylus crinitichelis Moreira, 1901 (Crustacea : Decapoda : Pinnotheroidea) under laboratory conditions

The goal of the present study was to investigate the growth rate of the crab Dissodactylus crinitiehelis, its molt increments, and the duration of the intermolt intervals under laboratory conditions, focusing on differences between sexes and between juvenile and adult phases. Crabs were collected at Flamengo Beach, Ubatuba, São Paulo State, Brazil, by scuba divers. In the laboratory, individuals were maintained in isolation and fed nauplii of Artemia sp. daily. The sex and carapace width of exuviae and dead crabs were recorded. During the juvenile phase, mean growth was 11.8 +/- 2.7% in males and 11.2 +/- 3.6% in females, with their respective intermolt intervals 25.4 +/- 9.2 and 26.4 +/- 8.3 d (mean +/- SD). After reaching morphological sexual maturity, the intermolt intervals increased to 33.4 10.1 d in males and 32.7 +/- 10.4 d in females, and the growth rates of both sexes slowed to 6.4 +/- 1.9% in males and 5.7 +/- 1.6% in females. There was a significant decrease in molt increment and an increase in intermolt intervals associated with the maturation from juveniles to adults, evidencing differential energy allocation during the last phase of ontogeny.

Larval cannibalism rates in the mangrove crab Ucides cordatus (Decapoda : Ocypodidae) under laboratory conditions

Predation of zoeas by megalopae of Ucides cordatus is frequently observed in the laboratory during larval rearing, a phenomenon that could considerably reduce the output of larviculture. Experiments were carried out in the present study to assess how the survivorship of larvae at the end of the larviculture is influenced by cannibalism by megalopae on the larvae of earlier stages, as well as on other megalopae. In addition, tests were performed to assess whether the adoption of different feeding protocols can decrease cannibalism rates. Experiments were carried out in plastic vials containing ocean water (salinity 25 g L-1) under controlled environmental conditions (26 degrees C and 16:8 h LD photoperiod). An ensemble analysis of all the developmental stages indicated that zoeal mortality rates were significantly higher in the presence of megalopae, a result that is consistent with cannibalism by megalopae. However, separate analysis for each developmental stage indicated that only zoea IV, V and VI show reduced survivorship. No cannibalism was detected among megalopae. Food supplementation using Artemia sp. at a density of 6 nauplii mL(-1) proved to be successful in reducing cannibalism rates, whereas supplementation at a lower density (0.3 nauplii mL(-1)) failed to show such an effect. The implications of these results for the larviculture of U. cordatus are discussed.

Desenvolvimento juvenil de Hepatus pudibundus (Herbst) (Crustacea, Decapoda, Calappidae), em laboratório

The Hepatus pudibundus (Herbst, 1785) juvenile development was studied in laboratory, under the morphological and systematical stand points. The eight early juvenile stages were obtained from larvae hatched from eggs of two ovigerous females, collected at the northern coast of the State of São Paulo, Brazil. The experiments were carried out in a climatically controlled room at 25 ± 1°C, and steady saltness of 34 . The youngs were maintened individually and food consisted of Artemia sp. nauplii and fragments of fish muscle.The first juvenile stage were particulary drawn and described. For the remaining juvenile stages the most representative frameworks were picked out, which allowed the characterization of the first eight stages. According to juvenile morphology studies, it was noted that secondary sexual characters differentation begins from the third stage.

Influência do fotoperíodo no crescimento e sobrevivência de póslarvas de piracanjuba Brycon orbignyanus (Valenciennes, 1849) (Osteichthyes, Characidae)

This paper aims at studying the influence of photoperiod on the cultivation of Brycon orbignyanus (Valenciennes, 1849) (Osteichthyes, Characidae) post-larvae submitted to four treatments: 0L-24D (L=Light; D=Dark), 10 - L14D, 14L - 10D and 24L-0D, with 3 repetitions. Post-larvae measuring 7.8±0.7mm and weighting 3.5±0.8mg were distributed in 12 aquariums (10L), stocked with 12 post-larvae per aquarium. Fishes were fed daily with Artemia sp. nanplii, in 10 days experiment. A positive relationship between the survival rate (88.9±9.7%) observed in the treatment with 24 hours of luminosity, and the lowest (58.3±8.3%), in the treatment with 24 hours of darkness. No difference was showed (P>0.05) in the mean length and weight of the post-larvae, although there was greater heterogeneity among the post-larvae cultivated at the longer darkness period.

Treinamento alimentar de pintado Pseudoplatystoma coruscans (Agassiz, 1829): sobrevivência, crescimento e aspectos econômicos

Pós-graduação em Aquicultura - FCAV

Desenvolvimento juvenil de duas espécies de siri (Crustacea, Decapoda, Portunidae) de importância econômica)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Juvenile development of Callinectes danae Smith, 1869 ( Crustacea, Decapoda, Brachyura, Portunidae) under laboratory conditions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessing the potential of partial replacing of artemia by practical inert diet in the larviculture of the Amazon River prawn

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)