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Ituverava, Brazil

Jomori R.K.,Laboratorio Of Aquicultura | Luz R.K.,Federal University of Minas Gerais | Takata R.,Federal University of Minas Gerais | Perez Fabregat T.E.H.,Santa Catarina State University | Portella M.C.,Sao Paulo State University
Pesquisa Agropecuaria Brasileira | Year: 2013

The objective of this work was to evaluate the effect of slightly saline water in an intensive larvicultureof tambaqui, matrinxã, apaiari, and piau, during the initial days of active feeding. Larvae were reared in artificial saline water, at concentrations from 0 (freshwater) to 14 g L-1 NaCl (at a 2.0 g L-1), and fed with two portions of Artemia nauplii, following a specific protocol for each species, in a completely randomized design, with 3 replicates. Tambaqui, matrinxã and apaiari larvae can be reared at saline concentrations till 2 g L-1 without impairing growth and survival. Piau larvae were more tolerant and endured saline water until 4 g L-1. At saline concentrations above that, fish mortality increased and reached 100% at 6 g L-1, for matrinxã and apaiari, and at 10 g L-1, for tambaqui. Saline water at 2 g L-1 provided a higher survival for matrinxã, and higher growth for tambaqui, apaiari and piau. These last two species showed a better growth performance with the highest quantity of nauplii. Slightly saline water at 2 g L-1 is beneficial to these studied species, as it optimizes larval growth potential and the use of Artemia nauplii as live food.


de Sandre L.C.G.,Sao Paulo State University | Buzollo H.,Sao Paulo State University | do Nascimento T.M.T.,Sao Paulo State University | Neira L.M.,Sao Paulo State University | And 5 more authors.
Journal of the World Aquaculture Society | Year: 2016

This study evaluated the application of stable isotopes of carbon as an alternative and more accurate method to determine gastrointestinal transit time (GTT) in fish by comparing it to the inert marker method. The stable isotope method detects alterations of the normal carbon flow in a biological system by analyzing naturally occurring isotopes of carbon, contrary to studies based on conventional techniques that apply external markers to the diet to determine GTT through visual observation of the color change in feces. Therefore, 320 pacu, Piaractus mesopotamicus juveniles were reared in 32 tanks under two different temperatures (25 and 29 C). The pacu juveniles received two different diets, one based on ingredients derived from C3 photosynthetic cycle plants and the other based on C4 plant ingredients, both containing titanium oxide (TiO2) as a marker. After 40 d, the isotopic signature of the diets was changed, and the marker was replaced by chromic oxide (Cr2O3). In the isotopic technique, the feces were analyzed to determine the exchange in the isotopic ratio of carbon δ13C. Both methods found that GTT was faster (nearly 6h) in fish at 29 C when using the C4/C3 feeding strategy and slower in fish at 25 C using the C3/C4 strategy (15h by inert marker and 18h by the isotopic method). In conclusion, GTT determination in pacu juveniles using the stable isotope technique exhibits the same accuracy obtained with the inert marker method at temperatures suitable (nearly 29 C) for the metabolism of these animals. © the World Aquaculture Society 2016.


Lopes T.D.S.,Sao Paulo State University | de Freitas T.M.,Sao Paulo State University | Jomori R.K.,Laboratorio Of Aquicultura | Carneiro D.J.,Sao Paulo State University | Portella M.C.,Sao Paulo State University
Journal of the World Aquaculture Society | Year: 2014

Skeletal anomalies in fish are frequent, representing a major problem for the aquaculture industry. The anomalies usually arise in the larval phase and worsen, persist, or recover over the ensuing stages of development. In addition to impairing larval quality, they compromise the growth, health, and food conversion of fish, lowering their economic value. This study evaluated the occurrence of skeletal anomalies in pacu larvae during the first 30d of development. The newly hatched larvae of six breeding pairs taken from the Paranapanema River (offspring A, B, C, D, E, and F) and subjected to induced spawning were reared separately for 30d, feeding on live prey (Artemia nauplii). Nearly 20 larvae from each breeding pair were killed and stored 1, 2, 4, 6, 8, 10, 13, 16, 19, 22, 25, and 30days post-hatching. The larvae were stained to differentiate cartilage and bones and examined under a stereo microscope. A total of 1310 larvae were checked for the presence (1) or absence (0) of anomalies in the head, vertebral column, and fins. Associations between growth parameters (total length [TL] vs. standard length [SL]; SL vs. vertebral column length [VL]) were obtained by regression. Correspondence analysis was used to correlate data on the different parameters evaluated. On completion of observation, larvae from pair E had the highest SL, whereas offspring F were the shortest. All types of skeletal anomalies were detected in the larvae irrespective of the offspring, affecting the normal growth of pacu larvae obtained from wild-caught breeders. © Copyright by the World Aquaculture Society 2014.


Portella M.C.,Sao Paulo State University | Jomori R.K.,Laboratorio Of Aquicultura | Leitao N.J.,Sao Paulo State University | Menossi O.C.C.,Sao Paulo State University | And 5 more authors.
Aquaculture | Year: 2014

In recent years, a number of South American freshwater fish have gained increasing attention for their potential in aquaculture, not only because of their excellent performance in farming systems but also to meet the high consumer demand for these species due to declining fishery resources. Many South American freshwater species are migratory and produce altricial larvae, with a small amount of yolk reserves. Unlike precocial freshwater species and altricial coldwater marine fish, these freshwater fish investigated have rapid yolk depletion and metamorphosis. Specific studies on the initial development of South American fish are scarce and fragmented. One of the most widely studied species is the pacu ( Piaractus mesopotamicus), farmed in warm continental waters. In the present review we compile new and published data on the initial development of pacu, including morphogenesis of the skeletal, muscle, digestive and sensory systems; compare it to other Neotropical species; and discuss the importance of this information to develop larviculture protocols. When pacu larvae exhaust yolk reserves, they initiate a new form of interaction with the environment, becoming exclusively exotrophic. This type of interaction is made possible by the rapid development of sensory, skeletal, locomotor and digestive structures. In addition to understanding fish ontogeny, studies on larval development are necessary to improve farming systems and larviculture techniques aimed at producing high-quality juveniles in aquaculture. © 2014 Elsevier B.V.


Oliveira Filho P.R.C.,Federal Rural University of Pernambuco | Oliveira C.A.F.,Laboratorio Of Microbiologia E Micotoxicologia Dos Alimentos | Sobral P.J.A.,Laboratorio Of Microbiologia E Micotoxicologia Dos Alimentos | Balieiro J.C.C.,Laboratorio Of Melhoramento Animal | And 2 more authors.
CYTA - Journal of Food | Year: 2015

Nile tilapia, Oreochromis niloticus, is one of the most cultivated fish species in Brazil. However, few studies evaluate how the stunning methods affect the meat quality of this fish. This study evaluates how both stunning methods, iced water and CO2 narcosis, affect the quality of tilapia meat that was stored refrigerated in ice (4°C) for up to 26 days. Tilapia stunned by CO2 narcosis showed less stress compared to iced water, which was evidenced by the higher ATP, and better meat color as well, evidenced by higher lightness (L) and lower redness (a) values. After sensorial analysis, fish were classified as extra-fresh during the first 2 days of storage; as fresh from day 3 to day 14, not fresh from day 15 to day 23; and as spoiled from day 23 onwards. Stunning of tilapia by CO2 narcosis can be an alternative to the traditional method of desensitization (iced water) used in Brazil. © 2014 Taylor & Francis.

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