Desenvolvimento de larvas de surubim-do-iguaçu (Steindachneridion melanodermatum) submetidas a diferentes dietas

Abstract

RESUMO -Para verificar o desenvolvimento de larvas de surubim-do-iguaçu (Steindachneridion melanodermatum) alimentadas com diferentes dietas, realizou-se um experimento em delineamento inteiramente casualizado, com cinco tratamentos e quatro repetições, em aquários de 35 L, cada um com 15 larvas (8,35±0,85 mm e 6,75±0,64 mg). Os tratamentos consistiram de cinco programas de alimentação: A -Artemia; R -ração; Z -zooplâncton; A+R -Artemia + ração; Z+R -zooplâncton+ração. Avaliou-se o desenvolvimento das larvas em ambiente iluminado durante 29 dias. Para avaliação da dieta e análise do conteúdo estomacal, a cada três dias foram coletadas larvas em cinco aquários adicionais. Nos tratamentos A+R e Z+R, os pesos médios finais das larvas foram significativamente maiores (659 e 571 mg) que nos outros tratamentos. A combinação de alimentos possibilitou os melhores resultados e, no tratamento R, a sobrevivência foi de 1,7%, diferindo dos demais. O canibalismo foi superior no R e no Z, que apresentaram taxas de 60 e 25%, respectivamente. O fornecimento de Artemia em associação à ração promoveu melhor desenvolvimento e maior sobrevivência às larvas de Steindachneridion sp.Palavras-chave: alimentação, alimentos inertes, larvicultura, seletividade alimentar, zooplâncton Development of Iguaçu surubim (Steindachneridion melanodermatum)larvae fed different diets ABSTRACT -An assay was conducted to evaluate the development of Iguaçu surubim (Steindachneridion melanodermatum) larvae fed different diets. The experiment was analyzed as a complete randomized design with five treatments and four replicates, in 35 L-aquaria, each one with 15 larvae (8.35±0.85 mm and 6.75±0.64 mg). The treatments consisted of five feeding programs: Artemia (A); diet (D); zooplankton (Z); Artemia with diet (A+D); and zooplankton with diet (Z+D). Larvae development was evaluated in illuminated environment during 29 days. For larvae feeding evaluation, three larvae were collected every three days, in five additional aquaria for stomach content analysis. In the A+D and Z+D treatments, the larvae average weight (659 and 571 mg) was significantly higher than the other treatments. The combinations of feeds resulted in better results and, in treatment R, it was observed survival rate of 1.7, that differs from the other treatments. Cannibalism rate was higher in D and Z treatments, with values of 60 and 25%, respectively. The A+D treatment provided the best development and the highest survival rate for Steindachneridion sp larvae.

Combination of diet and water salinity in larviculture of piabanha-do-Pardo ( Brycon vonoi , Lima 2017)

“…treatments was due to the salt water carried over from the hatching period. Similar conditions were observed by Soares et al (2000) and Feiden et al (2006), who registered conductivity variation depending on whether Artemia sp. was washed or not.…”

“…Feiden et al (2006) also observed this pattern. Differently, other larviculture tests showed slight pH variations (Soares et al, 2000), suggesting variability as a function of plankton composition and plant conditions.…”

“…They are unable to digest artificial feeds, therefore present low growth, and survival rates when fed this type of nutrition. Some examples species are matrinxã (B. cephalus) (Ceccarelli & Senhorini, 1996), tambaqui (C. macropomum) (Pedreira et al, 2015) and some Silurifirmes, like surubim-do-Iguaçu (S. melanodermatum) (Feiden et al, 2006) and pacamã (Lophiosilurus alexandri) (Pedreira et al, 2008a). Nevertheless, when feeds were offered in association to plankton, piracanjuba larvae were capable of absorbing theses feeds and, consequently, presented better yield than did those fed exclusively plankton (Pedreira & Sipaúba-Tavares, 2002), which contrasts the results observed for piabanha-do-Pardo.…”

<b>Influence of <i>Eichhornia crassipes</i> and Lemna sp. on the natural diet of <i>Astyanax altiparanae</i> Garutti & Britski, 2000 in the initial stages

“…confirm that the zooplankton is the main food for fish, especially in the first days of life, as reported to larvae of different species of fish by Fregadolli (1993), Sipaúba-Tavares (1993), Gerking (1994, Soares, Hayashi, Furuya, & Maranhão (1997), Furuya, Hayashi, Furuya, & Sakaguti (2002), Makrakis et al, 2005, Feiden et al (2006, Qu et al (2012).…”

“…Natural food is of paramount importance as it contributes with essential nutrients for growth, development and survival (Nikolsky, 1969;Mills, Widzowshi, & Jones, 1987). The shift from endogenous to exogenous feeding is a major difficulty faced in farming juveniles of rheophilic species (Gerking, 1994), as well as cannibalism that occurs in the first days of larval life (Feiden, Hayashi, & Boscolo, 2006). Therefore, studies on the diet during the early stages of fish development are of great importance to understand its role in the community, an opportunity to know one of the most critical steps for fish hatchery, which can help in the development of fish farming (Makrakis et al, 2005;Qu et al, 2012) and in determining priority areas for the maintenance of natural stocks.…”