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The lambari, Astyanax altiparanae, exhibits a great potential for aquaculture due to its omnivory, rapid growth and ease captive production. Despite of fish lipid metabolism being directly related to the dietary lipid consumed, which may lead to changes in fish growth, nothing much have been established regarding the lipid sources that can be applied in A. altiparanae captive production. Thus, this present research was conducted aiming to evaluate the growth performance and whole body composition of A. altiparanae fed with lipid sources of plant and/or animal origins. Were used a Completely Randomized design experiment with five treatments. The treatments consisted of isoproteic and isoenergetic diets, containing the following lipid sources: T1: linseed, chia and sunflower oils; T2: linseed and corn oils; T3: linseed, chia, corn and sunflower oils; T4: sunflower, corn and fish oils; T5: linseed, chia, sunflower, corn oils and bovine fat. Each treatment was replicated six times, where the experimental units consists of 10 fishes (averaged weight: 4.0 + 0.5 g) placed in an aquarium containing 80L of dechlorinated water. Were compared the growth performance parameters among the treatments by applying an one-way analysis of variance (ANOVA) at 5% significance (P < 0.05). The results revealed that both growth performance and whole body composition of A. altiparanae were not affected by the lipid source, which indicate that these fishes can efficiently use both vegetable lipid sources as well as mixtures of vegetable and animal lipid sources without any growth disadvantages. RESUMEN El lambari, Astyanax altiparanae, exhibe un gran potencial para la acuicultura debido a su crecimiento omnívoro, rápido y fácil de cautiverio. A pesar de que el metabolismo de los lípidos en los peces está directamente relacionado con los lípidos de la dieta, lo que puede conducir a cambios en el crecimiento de los peces, no se ha establecido mucho sobre las fuentes de lípidos que se pueden aplicar en la producción en cautiverio de A. altiparanae. Por lo tanto, esta investigación se realizó con el objetivo de evaluar el rendimiento del crecimiento y la composición del cuerpo de A. altiparanae alimentados con fuentes de lípidos de origen vegetal y animal. Se utilizó un experimento de diseño completamente al azar con cinco tratamientos. Los tratamientos consistieron en dietas isoproteicas e isoenergéticas, que contenían las siguientes fuentes de lípidos: T1: aceites de linaza, chía y girasol; T2: aceites de linaza y maíz; T3: aceites de linaza, chía, maíz y girasol; T4: girasol, maíz y aceites de pescado; T5: linaza, chía, girasol, aceites de maíz y grasa bovina. Cada tratamiento se repitió seis veces, las unidades experimentales consisten en 10 peces (peso promedio: 4.0 + 0.5 g) colocados en un acuario que contiene 80 litros de agua desclorada. Se compararon los parámetros de rendimiento de crecimiento entre los tratamientos mediante la aplicación de un análisis de varianza unidireccional (ANOVA) con una significancia del 5% (P

This research evaluated the effect of the simultaneous substitution of fish meal and fish oil at 0, 30, 50, 70 and 100% (termed SS0, SS30, SS50, SS70 and SS100, respectively) with both Spirulina (Arthrospira platensis) and linseed oil. The effect on growth, colour, fatty acid (FA) profile, and liver and muscle antioxidant response in mullets (Mugil liza) were evaluated. A full substitution was not possible due to a final body weight reduction (p 0.05). The colorimetric analyses showed an improvement in fillet colouration (p 0.05). Also, we found a saturation of carotenoids in muscle at 30% substitution. The content of highly unsaturated fatty acids - HUFA (DHA, EPA and ARA) in muscle diminished as the substitution level increased and, at the same time, the level of these FAs in the diet diminished. We found interesting evidence of elongation from 18:3n-3 to 20:3n-3 when substitution with linseed oil levels was above 50% but no desaturation to 20:4 or 20:5n-3 was found, which could insinuate a certain n-3 HUFA requirement under the experimental conditions. Moreover, we noted an increase in the antioxidant capacity up to the treatment SS70; the SS100 treatment showed a diminution in the antioxidant capacity. It is concluded that a partial inclusion of Spirulina and linseed oil (50%) is possible, and that this replacement can increase antioxidant responses, improve its growth performance and can modulate the mullets fillet quality without affecting negatively fillet fatty acid content.

The addition of pure carotenoids is a common practice in some aquaculture species production since its use in fish feed is known to improve carcass and antioxidant capacity. Spirulina (Arthrospira) cyanobacteria are a rich source of carotenoids that has proven health benefits for fish welfare. In the current experiment, four isonitrogenous (38%) isolipidic (9%) diets were made, including a control diet (free of β-carotene and Spirulina, SP0), β-carotene diet (50 mg kg−1, β0), and two Spirulina (Arthrospira platensis) diets with 2% (SP2) and 4% (SP4) of total feed inclusion. The experimental diets were given to juvenile mullets in a controlled recirculation system. The parameters evaluated were growth, colour, total carotene content of muscle, and antioxidant capacity of the liver and muscle. Significant differences were found (p

The objective of this work was to evaluate the fatty acid and lipid composition of oocytes, newly hatched larvae (NHL), first feeding larvae (FFL) and muscle tissue of female Brycon orthotaenia broodstock. Total and polar lipid was significantly (P0.05) abundant in oocytes and larvae in different stages of development. The lowest content (P0.05) of total lipids was found in the muscles, whereas total lipid content of oocytes, NHL and FFL did not show any significant difference. Polar lipid content was different (P0.05) between NHL and FFL. For the neutral the lowest values of C18:2n 6 occurred during the initial feeding period, whilst C20:4n 6 (AA) exhibited the highest percentage in FFL (P0.05). C22:6n 3 (DHA) was highest (P0.05) in FFL. The neutral lipid n-9 and n-6 was highest in muscle of females. The n-3HUFA was highest in NHL and in FFL, n-6HUFA was highest in FFL (P0.05). The ratios of DHA/EPA were higher (P0.05) in oocytes and FFL. In fatty acids of polar lipids, C20:5n 3 (EPA) did not show differences (P0.05) between stages. C18:3n 3 was highest (P0.05) in NHL and FFL. C20:4n 6 (AA) and C22:6n 3 (DHA) showed the highest percentages during the larval stages. The fatty acids n-3 series was significantly higher (P0.05) in FFL. The n-6HUFA was highest during development larval (P0.05). The increases DHA reflects the ability of the species to elongate and desaturate to obtain n-3HUFA from 18:3n 3, shows the importance of this fatty acid during early development.

Many species of reptiles maintain their body temperature behaviorally in a narrow range, even in the presence of considerable environmental temperature variation, by choosing microhabitats with different temperatures. In freshwater turtles, thermoregulation is generally achieved by aerial basking, even though they perform all other vital activities such as food consumption and reproduction in the water. Therefore, time budgets related to basking should be constrained and individuals should maximize the energy per unit time during basking, potentially by increasing basking frequency at noon during colder months and increasing use of basking when water temperature decreases. We analyzed basking behavior during the austral summer to study the effects of season, water temperature, and time of day in 2 South American freshwater turtles: Trachemys dorbigni (black-bellied slider) and Phrynops hilarii (Hilaire's side-necked turtle). We found that water temperature negatively affected basking frequency in...

This work aimed to determine fatty acid dynamics and lipid composition of female muscle, oocytes, newly hatched larvae (NHL) and first feeding larvae (FFL) of Prochilodus argenteus. Oocytes and NHL had the highest percentages of total lipids. Neutral lipids (NL) and polar lipids (PL) remained constant from oocytes through the larval stages (P < 0.05). Among NL, C18:2n 6 had its highest percentage in muscle (P < 0.05) and C18:3n 3 in muscle and oocytes. The highest percentages of arachidonic acid (AA) were in muscle and FFL. The highest percentages of n-9 and n-6 series were in muscle. The highest values of n-3HUFA were in the larval stages while the highest of n-6HUFA were in muscle and FFL. Percentage of ∑SFA in LN was highest in oocytes, NHL and FFL (P < 0.05) while ∑MUFA was highest in muscle, oocytes and NHL. The highest percentages of ∑PUFA were in muscle and FFL. For PL, however, C18:2n 6 and AA were highest in muscle (P < 0.05) while eicosapentaenoic acid was highest in muscle and oocytes. Percentage of ∑SFA in LP was highest in NHL and lowest in FFL and muscle. The highest percentage of ∑MUFA was in oocytes, NHL and FFL (P < 0.05). The highest percentages for series n-9 were in oocytes and FFL (P < 0.05), while the highest percentages for series n-6 were in muscle and oocytes. The lowest percentage for n-6HUFA was in NHL. The n-3 fatty acids were incorporated into the yolk from body reserves, which were stored prior to vitellogenesis and mobilized to the oocytes. The increase in docosahexaenoic acid reflects the ability of the species to lengthen and desaturate C18:3n 3 yielding n-3HUFA, thus demonstrating the importance of this fatty acid during early development.

Samples of eggs, newly hatched larvae (NHL), and larvae at the end of the lecithotrophic period (eight days after hatching) (LPL) of Lophiosilurus alexandri were collected to determine the amino acid and fatty acid profiles. Crude protein did not change throughout initial development and the concentration of lipids was highest in NHL. The content of the indispensable amino acids (IAA) isoleucine, leucine, and valine decreased in LPL, while in eggs and NHL they remained high and similar in value. The dispensable amino acids (DAA), such as aspartic acid, tyrosine, and glycine, increased in LPL, while alanine decreased. The percentage of neutral lipids increased in LPL. The saturated fatty acid content decreased during ontogeny, while monounsaturated fatty acids decreased only in LPL. The polyunsaturated fatty acid content was highest in LP. Polar fatty acids were found in higher percentages in eggs and NHL, but lower in LPL. Saturated fatty acid content decreased during ontogenetic development, while that of monounsaturated fatty acids decreased only in LPL. Polyunsaturated fatty acid content was highest in LPL. Protein content was maintained during ontogenetic development, while amino acid classes experienced changes. Lophiosilurus alexandri preferentially uses saturated and monosaturated fatty acids as an energy source during its early development. RESUMO Amostras de ovos, larvas recém-eclodidas (NHL) e larvas no final do período lecitotrófico (oito dias após a incubação) (LPL) de Lophiosilurus alexandri foram coletadas para determinar os perfis de aminoácidos e ácidos graxos. A proteína bruta não alterou durante o desenvolvimento inicial e a concentração de lipídios foi maior na NHL. O conteúdo dos aminoácidos indispensáveis (IAA) isoleucina, leucina e valina diminuíram em LPL, enquanto nos ovos e NHL eles permaneceram com valores elevados e semelhantes entre si. Os aminoácidos dispensáveis (DAA), como ácido aspártico, tirosina e glicina, aumentaram em LPL, enquanto a alanina diminuiu. A porcentagem de lipídios neutros aumentou em LPL. O teor de ácidos graxos saturados diminuiu durante a ontogenia, enquanto os ácidos graxos monoinsaturados diminuíram apenas em LPL. O teor de ácidos graxos poliinsaturados foi maior em LPL. Os ácidos graxos polares foram encontrados em porcentagens mais altas em ovos e NHL, e menores em LPL. O teor de ácidos graxos saturados reduziu durante o desenvolvimento ontogenético, enquanto que os ácidos graxos monoinsaturados diminuíram apenas em LPL. O teor de ácidos graxos poliinsaturados foi maior em LPL. O conteúdo de proteínas foi mantido durante o desenvolvimento ontogenético, enquanto as classes de aminoácidos sofreram mudanças. Lophiosilurus alexandri usa preferencialmente ácidos graxos saturados e monossaturados como fonte de energia durante o desenvolvimento inicial.

In order to better understand the functioning of aquatic environments, it is necessary to obtain accurate diet estimations in food webs. Their description should incorporate information about energy flow and the relative importance of trophic pathways. Fatty acids have been extensively used in qualitative studies on trophic relationships in food webs. Recently a new method to estimate quantitatively single predator diet has been developed. In this study, a model of aquatic food web through quantitative fatty acid signature analysis was generated to identify the trophic interactions among the species in the Rocha Lagoon. The biological sampling over two consecutive annual periods was comprehensive enough to identify all functional groups in the aquatic food web (except birds and mammals). Heleobia australis seemed to play a central role in this estuarine ecosystem. As both, a grazer and a prey to several other species, probably H . australis is transferring a great amount of energy to upper trophic levels. Most of the species at Rocha Lagoon have a wide range of prey items in their diet reflecting a complex food web, which is characteristic of extremely dynamic environment as estuarine ecosystems. QFASA is a model in tracing and quantitative estimate trophic pathways among species in an estuarine food web. The results obtained in the present work are a valuable contribution in the understanding of trophic relationships in Rocha Lagoon.

Quantitative fatty acid analysis (QFASA) is a statistical model designed to quantitatively estimate predator diets using fatty acid (FA) signatures among the predator and its potential prey. QFASA estimated the diet of a migratory flatfish Paralichthys orbignyanus over its fattening stage in the Rocha lagoon (a semi-closed estuary) where all prey available to this top predator species are well known. A 20-week controlled feeding trial obtained calibration coefficients (CC) for P. orbignyanus fed two types of prey (silverside and menhaden). Several subsets of FA were tested in order to elucidate which is the most suitable for applying QFASA to this species. QFASA was applied to all CC and FA subsets to validate the model. The model predicts better the consumed diet with silverside CC than with menhaden CC. The subset which best adjusts the diet over the validation process, includes approximately 34% of total FA, containing mainly dietary FA. The diet estimation in nature for P. orbignyanus varied according to whether the model is applied with or without CC. When the diet was estimated without CC, results were similar to those based on stomach content analysis (reported in previous studies); it fed mainly on silverside (~ 88%), but also some minor soft-body species that are only evident using this kind of methodology (QFASA). When the diet was estimated with silverside CC, a higher presence of silverside (~ 97%) was observed. These results seem to indicate a tendency to overestimate the presence of the item used as prey for CC calculations.

Paralichthys orbignyanus and Paralichthys patagonicus are flatfish with different life history traits, having in common the condition of breeding in seawater. Paralichthys patagonicus remain their whole life in open seawater and Paralichthys orbignyanus are sometimes found in brackish water bodies. As marine and estuarine food webs have different fatty acid (FA) compositions, the aim of this study was to characterize the gonadal maturation of P. orbignyanus and P. patagonicus females through the analysis of lipid content and FA profile in order to understand to what extent life history traits are reflected in the ovarian composition. During gonadal maturation lipid content increased and FA profiles changed in both species, but the lipid increase was greater in P. orbignyanus. The N-3FA and n-3HUFA proportions increased in both species but were higher in P. orbignyanus. The differences between the lifestyles of these species were reflected in the ovarian FA profile mainly as a result of differences in their FA metabolism, causing a greater accumulation of n-3FA and n-3HUFA in P. orbignyanus than in P. patagonicus. The higher lipid accumulation in P. orbignyanus’ ovaries could indicate that this species, feeding in brackish water bodies, has the possibility of storing more energy than P. patagonicus. ResumoParalichthys patagonicus e Paralichthys orbignyanusapresentam diferentes atributos nas suas histórias de vida, embora ambas se reproduzam no mar. Paralichthys patagonicus permanece toda a vida em águas abertas, enquanto P. orbignyanus é comumente encontrado em corpos de água salobra. Considerando que redes alimentares marinhas e estuarinas têm diferente composição de ácidos graxos (FA), o objetivo deste estudo foi caracterizar a maturação gonadal de fêmeas de P. orbignyanus e P. patagonicus analisando o conteúdo lipídico e perfil FA, a fim de estabelecer se as diferenças nas histórias de vida são refletidas na composição do ovário. Durante a maturação gonadal, em ambas as espécies, houve aumento do teor lipídico e o perfil FA mudou, mas o incremento foi maior em orbignyanus. As proporções de N-3FA e n-3HUFA aumentaram em ambas as espécies, mas foram maiores em P. orbignyanus. As diferenças entre os estilos de vida destas espécies foram refletidas no perfil de FA dos ovários, principalmente como resultado das diferenças no metabolismo de FA, causando maior acúmulo de n-3FA e n-3HUFA em P. orbignyanus. O maior acúmulo de lipídios nos ovários de P. orbignyanus poderia indicar que esta espécie, ao se alimentar em águas salobras, tem a possibilidade de armazenar mais energia do que P. patagonicus.