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URI permanente para esta coleçãohttps://rihomolog.furg.br/handle/1/362

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1999 - 199912000 - 2009172010 - 201311

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Assunto: search.filters.subject.Growth

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Agora exibindo 1 - 10 de 29
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    Efeito da temperatura sobre o desempenho da Rã-touro (Rana catesbeiana Shaw, 1802)
    (1999) Figueiredo, Mario Roberto Chim; Agostinho, Claudio Angelo; Baêta, Fernando da Costa; Lima, Samuel Lopes
    Este estudo foi realizado para avaliar os efeitos do ambiente sobre a performance de rã-touro (Rana catesbeiana Shaw, 1802), criada em gaiolas de fibra de vidro instaladas no interior de estufas climatizadas. Após um período inicial de 15 dias de adaptação às instalações, à temperatura constante de 25,0ºC, os seguintes tratamentos foram aplicados: temperaturas de 23,0; 26,0; 29,0; 32,0; e 35,0oC, por 30 dias, para rãs com 100 g PV inicial; 24,5; 26,0; 27,5; 29,0; 30,5; e 32,0oC, também por 30 dias, para rãs com 20 g PV inicial; e a combinação das temperaturas de 26,0 e 29,0oC com os fotoperíodos de 8, 12 e 16 h de luz a cada 24 horas, para rãs com 100 g PV inicial. Derivando-se as equações de regressão que explicam os efeitos de temperatura sobre o desempenho das rãs, estimaram-se melhores ganhos de peso à temperatura de 27,6 e 30,1oC, para rãs com 100 e 20 g PV inicial, respectivamente, com melhor crescimento a 28,2oC, para as rãs de 100 g PV inicial, e a 29,7ºC, para as rãs de 20 g PV inicial. A temperatura interagiu com fotoperíodo nos seus efeitos sobre ganho de peso e crescimento corporal, peso e rendimento de carcaça, consumo de alimentos e conversão alimentar.
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    Culture of cobia rachycentron canadum (l) in near-shore cages off the brazilian coast
    (2011) Sampaio, Luís André Nassr de; Moreira, Cauê Bonucci; Miranda Filho, Kleber Campos; Rombenso, Artur Nishioka
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    Abundance, distribution and population dynamics of the short fin squid illex argentinus in southeastern and southern Brazil
    (2013) Haimovici, Manuel; Santos, Roberta Aguiar dos; Bainy, Mara Cristiane Rodrigues Silveira; Fischer, Luciano Gomes; Cardoso, Luis Gustavo
    Surveys and commercial fishing landings data of the short fin squid Illex argentinus were analyzed to address three related issues: the seasonal and spatial pattern of abundance; seasonal and regional variation of growth and maturation; and the interannual variation in the size at maturity and growth from Southern Brazil (SB, 28◦–34◦S) and Southeastern Brazil (SEB, 23◦–28◦S). Overall, 2455 specimens were examined for maturity and 337 specimens had their daily increments in the statoliths recorded. Aged specimens from SB ranged from 51 to 275 days, 55 to 354 mm ML and 2.4 to 1098 g. It was observed that (1) I. argentinus is a common component of the nekton on all the outer shelf and slope and appears to be more abundant south of Santa Marta Grande Cape, where the largest catches were obtained in the autumn survey. (2) Spawning and hatching occurs year round along all the region. (3) In SB growth was faster and maturity was attained at larger sizes in the cold season (June to November) and no differences between seasons were observed in the mean age of mature specimens. (4) In 2001/2002, growth was faster, mature squids were in mean 159 days old and most were under 210 days, in 2007/2008, growth was slower, mean mature age was 191 days and most were 250 days. (5) In SEB, maturity was attained at smaller sizes and it is likely that maturity is attained at a lower age and the lifespan is shorter. In the northern range of its distribution I. argentinus is characterized by a decreasing adult size toward lower latitudes, a short and variable lifespan with hatching and spawning in all seasons
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    Population dynamics and reproduction of wild longsnout seahorse Hippocampus reidi
    (2012) Mai, Ana Cecilia Giacometti; Canziani, Gonzalo Velasco
    Life-history characteristics such as growth, mortality, and size at sexual maturity of the seahorse Hippocampus reidi were investigated in situ in north-eastern Brazil from August 2006 to July 2007. The von Bertalanffy growth constant K was estimated at 1.195 year21 and L1 was set as 20 cm according to Taylor’s relationship, using a Lmax of 19 cm. The smallest male with a brood pouch and the smallest male with a fully mature pouch measured 9 and 9.5 cm (height), respectively, while the smallest mature female measured 8.8 cm. Appropriate reproductive individuals were recorded throughout the study, with peaks from May to November. The size of first effective reproduction (carrying embryos) was 12.4 cm for males, a value higher than previously reported. Estimated instantaneous rate of natural mortality ranged from 1.43 to 1.58 year21. The estimated life span for the species was 30 months.
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    Estimation of zooplankton secondary production in estuarine waters: Comparison between the enzymatic (chitobiase) method and mathematical models using crustaceans
    (2012) Avila, Tatiana Ramos; Machado, Anderson Abel de Souza; Bianchini, Adalto
    Sampling was seasonally performed in the Patos Lagoon estuary (Rio Grande, RS, Southern Brazil) to estimate zooplankton biomass and production comparing values obtained using an enzymatic (chitobiase) method and the traditional mathematical models based on growth. Comparison of data obtained from zooplankton samples collected with 90 and 200-μm mesh nets showed that net selectivity influences the estimation of zooplankton biomass and production. Furthermore, it showed differential results for dominance of taxa and proportions of developmental stages in samples. Differences among samples collected at the different sites in the same season were observed using either the mathematical models or the enzymatic method. The two different approaches were also able to detect the seasonal variation in production. In a broad view, data obtained using the chitobiase method showed a similar pattern of zooplankton production compared to those obtained with the traditional mathematical models based on growth. However, values estimated using the enzymatic method were systematically higher than those obtained with the mathematical models. Maximum total production values were estimated as 12.5, 9.2 and 7.9 mg C m−3 day−1 for the “chitobiase method”, “Huntley model”, and “Hirst model”, respectively. Considering all sampling sites and seasons, the magnitude of this difference corresponded to 1.95 and 2.49mg C m−3 day−1 for the “Huntley model” and the “Hirst model”, respectively. These findings indicate the reliability of the enzymatic method in estimating crustacean production also in estuarine environments of changing salinity, as previously demonstrated for marine waters. In addition, the use of this method is more practical and comparatively less time-consuming and cheaper than the use of the mathematical models based on growth.
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    Effect of different food items on the survival and growth of Farfantepenaeus paulensis (Pérez-Farfante 1967) postlarvae
    (2006) Soares, Roberta Borda; Peixoto, Silvio Ricardo Maurano; Wasielesky Junior, Wilson Francisco Britto; D'Incao, Fernando
    The effect of different food items on growth and survival was assessed in four feeding experiments conducted consecutively using distinct Farfantepenaeus paulensis (Pérez-Farfante) postlarval growing stages: (1) PL1–PL4 (i.e. from postlarvae 1-day old to postlarvae 4 days old); and (2) PL4–PL10; (3) PL10–PL18 and (4) PL18–PL30. For each trial, 10 feeding treatments were tested in triplicate: Unf, unfed shrimp; Tt, Tetraselmis chuii; Ch, Chaetoceros calcitrans; C, commercial diet; AC, decapsulated Artemia cysts; C+Ph, commercial diet and phytoplankton combination; FA, frozen Artemia nauplii; A, live Artemia nauplii; A+Ph, Artemia nauplii and phytoplankton combination and Mix, mixture of phytoplankton, live Artemia nauplii and commercial diet. Postlarvae feed phytoplankton (i.e. Tt or Ch) exclusively exhibited low growth and survival. The best results for growth and survival were observed in the A, A+Ph and Mix treatments. Frozen Artemia nauplii was found to be suitable for younger postlarvae (PL1–10), whereas AC may be offered from PL4 to PL30. In general, the present findings indicated that even at an early postlarval stage, F. paulensis presents a high degree of carnivory, and a diet containing Artemia is recommended.
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    Biofiltering efficiency, uptake and assimilation rates of Ulva clathrata (Roth) J. Agardh (Clorophyceae) cultivated in shrimp aquaculture waste water
    (2009) Copertino, Margareth da Silva; Tormena, Thiago; Seeliger, Ulrich Christian Karl Heinz Bruno
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    Growth and biochemical composition of the diatom Chaetoceros cf. wighamii brightwell under different temperature, salinity and carbon dioxide levels. I. Protein, carbohydrates and lipids
    (2005) Araujo, Sirlei de Castro; Garcia, Virginia Maria Tavano
    The marine diatom Chaetoceros cf. wighamii has been investigated for its potential use as food in mariculture. In this work, we investigated temperature (20, 25, and 30 8C), salinity (25 and 35) and carbon dioxide addition (air and air + CO2) effects on growth and biochemical composition of C. cf. wighamii, under laboratory conditions. C. cf. wighamii growth and biomass was primarily affected by carbon dioxide addition and to a lesser extent by temperature and salinity. In general, lipid and carbohydrate content were higher at lower temperatures (20 and 25 8C) while protein was unaffected. Carbon dioxide addition increased protein and lowered carbohydrates, but had no effect on lipid content. Carbohydrates were enhanced while lipids and protein decreased at the highest salinity (35). These results should be taken into consideration when evaluating the nutritional value of this microalga for marine invertebrate larvae. D 2005 Elsevier B.V. All rights reserved.
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    Contribution of biofilm to water quality, survival and growth of juveniles of the freshwater crayfish Cherax quadricarinatus (Decapoda, Parastacidae)
    (2012) Viau, Verónica; Ostera, Juan; Tolivia, Analía; Ballester, Eduardo Luis Cupertino; Abreu, Paulo Cesar Oliveira Vergne de; Rodríguez, Henrique
    The effect of biofilm as an alternative food source and/or a complement for improving culture was assayed for early and advanced juveniles of Cherax quadricarinatus. For both kinds of juveniles, higher values of survival were seen in the experimental groups provided with either biofilm (B) or a combination of both formulated food and biofilm (B+F), compared to the group only receiving formulated food (F). Such higher survival was associated to a better water quality maintained by biofilm, in terms of low levels of both ammonium and nitrite, together with high levels of pH and dissolved oxygen. As for growing, specific growth rate was higher in the groups fed with formulated food, but only for early juveniles. Considering the crayfish biomass at the end of the experiment (i.e., an integrative index of both survival and growth), the best results were seen in the B+F group, for both kind of juveniles. The main micro-organisms present in biofilm were chlorophytas, xantophytas, pennate diatoms, cyanobacteria, flagellates, ciliates, rotifers and nematodes. Most of these items were found in the stomach of crayfishes fed on biofilm. The hepatopancreatic levels of total lipids were higher in animals of both B+F and F groups, compared to those of B group, while energetic reserves in the abdominal muscle showed no differences among experimental groups, for any kind of juveniles. Therefore, biofilm could be considered as a good complement for the culture system of C. quadricarinatus juveniles, mainly by improving survival through the maintenance of a good water quality. Combination of biofilm and formulated food has shown the best results, in terms of both survival and growth of juvenile crayfish.
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    Produção de larvas e juvenis do peixe-rei marinho odontesthes argentinensis submetidos à diferentes freqüências alimentares
    (2007) Sampaio, Luís André Nassr de; Tesser, Marcelo Borges; Oliveira, Mauren
    As dificuldades encontradas na alimentação de larvas e juvenis de peixes limitam o sucesso da piscicultura marinha. Portanto, este estudo foi realizado com o intuito de avaliar os efeitos de diferentes freqüências alimentares sobre a sobrevivência e o crescimento de larvas e juvenis do peixe-rei marinho Odontesthes argentinensis. Larvas recém-eclodidas foram alimentadas com náuplios de Artemia 1, 2 e 4 vezes ao dia e os juvenis (peso médio de 95 mg) foram alimentadas com ração 2, 4 e 6 vezes ao dia, todos os tratamentos foram realizados em duplicata. Os resultados foram analisados com Análise de Variância (ANOVA) seguida do Teste de Tukey ao nível de significância de 95%. A sobrevivência do peixe-rei não foi significativamente afetada pela freqüência alimentar empregada(P>0,05), independente do tratamento a sobrevivência foi sempre superior a 90% para as larvas e juvenis. Por outro lado, diferenças significativas foram encontradas para o crescimento (P<0,05), as maiores larvas e juvenis foram aqueles criados com as freqüências alimentares mais elevadas. Os resultados deste trabalho demonstram que a performance das larvas e juvenis de peixe-rei é aprimorada quando eles são alimentados várias vezes ao dia.