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Introduction: Understanding the various aspects of the reproductive biology of fish is a key step towards applying effective strategies for sustainable management of fishery resources. Objective: We aimed to evaluate the sex ratio, reproductive period and lengths at first maturity for 30 fish species caught in the Verde River, upper Paraná River Basin, Brazil. Methods: Fish were sampled monthly from November 2010 to March 2011 and from October 2011 to February 2012, and sampled quarterly from May to August in 2011 and 2012; totaling 14 samples. Fish were measured and weighed in the laboratory. In addition, gender and gonadal developmental stage were identified macroscopically. Subsequently, the sex ratio was determined and significant differences were tested using the chi-square (χ²) method. The reproductive period was determined with the use of gonadal developmental stages and the gonadosomatic index. Lastly, length at first maturity was estimated only for the species that presented individuals with sufficient immature and mature gonads to adjust the model. Results: Of the captured individuals, 51.5 % were male, and 48.5 % were female. Fifteen species showed significant differences in their sex ratios. The reproductive period for most species occurred from October to February, with reproductive peaks in November, December and January. The length at first maturity was estimated for only five species, including Salminus brasiliensis, a keystone species. Conclusions: The sex ratios revealed that for many species, there is a predominance of males over females, which was not expected for this parameter. The reproductive period follows the same pattern observed in Neotropical fish. However, it is noteworthy that some species are starting their reproduction in August. Lastly, estimating length at first maturity for most Neotropical fish remains a challenge, which may lead to difficulties in the use of protective measures to maintain fisheries and conserve fish species. Resumen Introducción: Comprender los aspectos de la biología reproductiva de los peces es un paso fundamental para la aplicación de estrategias efectivas para la administración sostenible de los recursos pesqueros. Objetivo: Este estudio tuvo como objetivo evaluar la proporción sexual, el período reproductivo y la longitud en la primera madurez para 30 especies de peces capturados en el río Verde, cuenca alta del río Paraná, Brasil. Métodos: Se tomaron muestras de peces mensualmente de noviembre 2010 a marzo 2011 y de octubre 2011 a febrero 2012, y trimestralmente de mayo hasta agosto de 2011 y 2012; totalizando 14 muestras. En el laboratorio, los peces capturados fueron medidos y pesados. Además, el sexo y la etapa de desarrollo gonadal se identificaron macroscópicamente. Posteriormente, se determinó la proporción sexual y se analizó si había diferencias significativas utilizando el método de chi-cuadrado (χ²). El período reproductivo fue determinado con el uso de las etapas de desarrollo gonadal y el índice gonadosomático. Finalmente, la longitud en la primera madurez fue estimada solamente para las especies que presentaron individuos con suficientes gónadas inmaduras y maduras para ajustar el modelo. Resultados: De los individuos capturados, el 51.5 % fueron machos y el 48.5 % hembras. Quince especies presentaron diferencias significativas en la proporción sexual. El período reproductivo para la mayoría de las especies ocurrió de octubre a febrero, con picos reproductivos en noviembre, diciembre y enero. La longitud en la primera madurez fue estimada solamente para cinco especies, incluyendo Salminus brasiliensis, una especie clave. Conclusiones: La proporción sexual reveló que para muchas especies hay predominio de machos sobre hembras, lo cual no se esperaba para este parámetro. El período reproductivo sigue el mismo patrón observado en peces neotropicales. Sin embargo, vale la pena señalar que algunas especies están comenzando su reproducción en el mes de agosto. Por último, estimar la longitud en la primera madurez para la mayoría de los peces neotropicales sigue siendo un reto, lo que puede llevar a dificultades en el uso de medidas de protección para mantener la pesca y conservar las especies de peces.

The accumulation of four human pharmaceuticals active compounds (HPhAC) in the muscle of four fish species of the Rio de la Plata Basin were assessed regarding the compound logP and pKa, and fish trophic levels. For Prochilodus lineatus, accumulation was compared to hepatic biotransformation enzymes and fish from two sampling areas with different urbanization degree. Species were the detritivore Prochilodus lineatus, the omnivores Megaleporinus obtusidens and Pimelodus maculatus, and the piscivorous Salminus brasiliensis. Sampling areas were the Inner Rio de la Plata Estuary (RLP), in front of the Buenos Aires Metropolitan Area, and at the Lower Uruguay River (URU), a relatively unpopulated area. Carbamazepine, atenolol, enalapril, and sildenafil concentrations in fish muscle were analyzed by HPLC-MS. EROD, BROD, and GST activities were measured in P. lineatus liver. Average (maximum) concentrations and detection frequency were: Atenolol 24.4 (69.4) μg kg−1, 60%; carbamazepine 5.5 (45.8) μg kg−1, 19%; enalapril 7.0 (56.9) μg kg−1, 28%; sildenafil 17.1 (71.6) μg kg−1, 56%. Enalapril and sildenafil detection in fish was first-time reported. Atenolol and carbamazepine concentrations were positively correlated. No correlation was observed between HPhAC accumulation and logP or pKa. A potential biomagnification trend was observed for atenolol, showing higher accumulation in S. brasiliensis. HPhACs accumulation was higher for P. lineatus collected at URU, but GST and BROD were significantly higher for individuals sampled at RLP and were positively correlated. A significant negative correlation was observed for enalapril and BROD. The study contributes to the knowledge of the accumulation of HPhACs in fish.

Cost and environmental restrictions limit the use of fishmeal (FM) in aquafeeds and plant protein (PP) sources. Soybean by-products are important alternative; however, their antinutritional factors may reduce fish growth. This study evaluates the effect of FM substitution for PP (soybean meal and soy protein concentrate) in diets of dourado (Salminus brasiliensis), a promising species for fish farming and empirically considered highly tolerant to PP-based diets. A control diet was formulated to contain 20 % of fishmeal and 61 % of plant protein (SBM) and other five diets with decreasing FM graded levels (16 %, 12 %, 8 %, 4 %, 0 %), which were replaced by soybean protein concentrate (SPC), comprising six treatments and four replicates. Fifteen dourados (6.73 ± 0.2 g) were stocked into 200 L tanks in a recirculating system, fed with experimental diets three times a day to apparent satiation for 90 days. Growth performance, food conversion ratio, protein efficiency ratio and protein retention efficiency of fish were impaired when FM substitution exceeded 13.05 % (the broken line analysis method). Histological analysis of intestinal mucosa showed a decrease in villus height when fishmeal was totally replaced by PP, which probably impaired digestive functions of fish and reflected in a severe loss on growth performance. Made available in DSpace on 2020-01-02T18:10:16Z (GMT). No. of bitstreams: 1 1678992Xsa7702e20180046.pdf: 304444 bytes, checksum: 86445bda871187c90b07764a6b669084 (MD5) Previous issue date: 2020

Hydrolysates of slaughtering plants by-products are among the most promising feedstuffs for aquafeed formulations, supplying diets with amino acids and small peptides which perform functions ranging from palatability enhancers to nutrient-rich ingredients to immunity modulators. This study evaluated growth performance, blood and immunological parameters, and gene expression of food intake-regulating hormones in juvenile dourado Salminus brasiliensis (Cuvier, 1816) (25.07 ± 3.9 g) fed vegetable-based diets supplemented with swine liver hydrolysate [SLH] (30, 60, 90, 120, 150, and 180 g kg−1). Hematological and immunological factors did not change for either vegetable- or swine liver hydrolysate-based diets. Feed consumption was improved in fish fed a diet containing 30 g kg−1 SLH, while 150 g kg−1 of inclusion improved growth performance. Results suggest an effect of feeds on cocaine and amphetamine regulated transcript (CART) expression, which had higher expression levels in the hypothalamus of fish fed the diet containing 150 g kg−1 of SLH. Cholecystokin (CCK) expression levels only increased in fish fed 60 g kg−1 SLH compared to the control diet, and this may be related to gastric tract filling rather than dietary peptides.

Molecular data of Henneguya chydadea Barassa, Cordeiro and Arana, 2003, found in the gill filaments of Astyanax lacustris bred in fish farm in the State of Mato Grosso do Sul, Brazil was obtained in order to estimate their phylogenetic position among other platysporines myxosporean. The prevalence of the parasite was 28.1% and the range intensity was 1-3 plasmodia per fish. The shape and measurements of mature myxospores were consistent with the characteristics previously defined to H. chydadea. The SSU rDNA sequence of the myxospores of H. chydadea resulted in a total of 1405 nucleotides, and this sequence did not match any of the myxozoan available in the GenBank. Phylogenetic analysis showed H. chydadea within the clade of histozoic myxosporeans and closed together with Henneguya rotunda and Myxobolus pantanalis reported in the gill arch and fins and gill filaments of Salminus brasiliensis respectively. Nonetheless, the SSU rDNA sequences of H. chydadea, H. rotunda and M. pantanalis have only 85.2% and 84.4% similarity, respectively. This is the first molecular study of a Henneguya species that parasitizes a fish belonging to the genus Astyanax in South America. The importance of myxosporeans introduction to new locations along with infected cultured host is emphasized.

Vitamins are dietary, organic compounds required for normal growth, reproduction and health of animals, fish included. Dietary vitamins also drive immunological responses of fish and information in that regard is still scarce. This work studied dietary vitamin A requirement of dourado Salminus brasiliensis, a novel target of intensive fish farming and research efforts. Juvenile dourado were stocked in 500-L tanks and fed for 101 days with six diets containing 1115.3; 3126.4; 8818.1; 18,256.1; 24,185.3 and 30,270.4 IU vitamin A kg−1 diet, and then sampled for growth performance indices, carcass composition, vitamin A contents in liver, hematological figures and leukocytes respiratory activity (LRA). Sub groups (n = 8) were inoculated intraperitoneally with Aeromonas hydrophila suspension (106 CFU) and sampled for hematology and LRA one week later. A break point for weight gain was detected at 3143 IU vitamin A kg−1 diet and the lowest specific growth rate was recorded for fish fed diets containing 1115.3 IU vitamin kg−1 diet, which also had lowest erythrocyte count and blood hemoglobin contents. Hematocrit and total plasma protein of fish decreased after bacterial challenge, regardless of dietary vitamin A contents. Dietary vitamin A requirement of dourado was determined at 8500 IU kg−1; although higher levels did not hamper performance and health, they are not recommended given the possibility of hypervitaminosis. The higher leukocytes activity related to vitamin A administration is a solid indicative of immunomodulation activity of this vitamin for the species.

Recent studies have identified patterns of genetic organization during schooling in the reproductive period of several Neotropical freshwater migratory fish. However, population segregation during non-reproductive periods is still unknown for most species. In this study, we investigated the genetic structure of populations of Salminus brasiliensis, a high-value large migratory freshwater fish, sampled during the non-reproductive season. We analysed 89 adults from Uruguay River Basin (Brazil) collected during the two consecutive non-reproductive periods, and assessed the genetic diversity levels using eleven microsatellite loci. Our results showed that populations are genetically structured, suggesting these fish can remain grouped likely due to a cooperative behaviour, not related to reproduction, in a typical shoaling behaviour. Besides, we found high genetic diversity for S. brasiliensis from the Turvo State Park area, highlighting the importance of this conservation unit as a relevant area for maintaining the genetic variability of S. brasiliensis in the Uruguay River.

Catch-and-release (C&R) angling is a powerful tool for reducing impacts on recreationally targeted fishes. Although C&R can be mandated in fisheries through regulation, voluntary adoption and infor...

Fishmeal (FM) is a high-cost and scarce feedstuff. Notwithstanding, the formulation and processing of diets for carnivorous fish strongly rely on FM as a protein source, given its palatabil...

Diets for carnivorous fish ordinarily contain large proportion of fish meal (FM), a high-cost and restricted feedstuff. Animal by-product hydrolysates are high-quality feedstuffs and potential surrogates to FM in fish diets. This study evaluated the performance of juvenile dourado Salminus brasiliensis, a carnivorous Characin, fed with increasing levels of swine liver hydrolysate. Juvenile dourado (4.57 ± 1.25 g) were stocked into 20,300-L, indoor plastic tanks (15 fish per tank), closed-loop recirculating system in a totally randomized experimental design (n = 4), and fed to apparent satiation for 61 days with practical diets containing graded levels of swine liver hydrolysate – SLH (0, 70, 140, 210 and 280 g kg− 1). Fish fed the SLH14 diet had higher feed intake and weight gain. Fish fed the SLH28 diet had the lowest rates of feed efficiency ratio (FER), protein efficiency ratio (PER), energy retention ratio (EER) and protein retention ratio (PRR). Diets containing in excess of 140 g SLH kg− 1 probably caused reduction of protein synthesis by fish, possibly resulting from higher proportion of small peptides and free amino acids in the feedstuff, which possibly elicited higher amino acid catalysis and increased nitrogen excretion. The lowest values of blood lysozyme were recorded for fish fed diet SLH7; on the other hand the oxidative burst was not influenced by the diet. Higher nitrogen excretion was recorded for in fish fed diets containing the highest levels of hydrolysate. Ultrafiltration of swine liver hydrolysates may elicit increasing the proportion of the product in fish diets and further studies on the economic feasibility of swine liver hydrolysate may shed additional light regarding its use as surrogate protein sources.

Sport fishing is an activity responsible for moving millions of dollars around the world. However, this activity is also considered to cause habitat degradation and promoting several negative effects on the ichthyofauna. The ``Iguacu Dourado'' project, presented here, seeks to intensify the potential of sport fishing in the Iguacu River Basin. Although not explicit, the project intends to introduce Dourado (Salminus brasiliensis), as well as to encourage sport fishing of the species in the Iguacu River Basin. Twenty specimens were captured in the Salto Santiago and Salto Osorio reservoirs from 2003 to 2016, thus indicating that the invasion of S. brasiliensis can be successful and extremely harmful to the endemic fauna of the basin. We believe that the so-called project is characterized by an attitude of eco-vandalism, promoting the illegal release of species outside its area of occurrence. Awareness-raising measures as well as educational programs should be addressed so that the population can be informed about the issue of invasion of non-native species.

Golden dorado (Salminus brasiliensis) is increasing in popularity as a target of recreational anglers practicing catch-and-release (C&R) in northern Argentina and bordering countries, however science-based best practices have yet to be developed for this iconic freshwater gamefish. We assessed the consequences of C&R on golden dorado captured by anglers on the Juramento River, in Salta, Argentina. Physical injury, physiological stress responses (blood glucose, lactate, pH), reflex impairment, and movement response post-release were compared among handling treatments for golden dorado. The 0 min and 2 min air exposure groups had significantly higher blood glucose and blood lactate concentrations relative to fish in the baseline group, while blood pH indicated evidence of acidosis in the 2 min air exposure treatment relative to baseline values. Golden dorado in the 2 min air exposure group also had significantly greater reflex impairment compared to fish without air exposure. An additional 24 golden dorado were affixed with radio tags to examine short-term (20 min) post-release behavior with air-exposure treatments of 0 min (n = 11) and 2 min (n = 9), as well as fish that were transported downstream in submerged recovery bags (n = 4). Subsequent relocations of tagged golden dorado were conducted every 1–2 days up to 8 weeks after capture. Upon immediate release, fish often exhibited fallback (−43 ± 49 m, n = 20), although post-release movement was not significantly different among treatment groups. Fallback distance was correlated with total reflex impairment scores. The translocated fish released downstream exhibited greater upstream movement immediately following release, with three fish returning to the location of capture within 4–12 days. No immediate mortality was observed for golden dorado in the physiology assessment, and limited evidence of short-term mortality was present for tracked fish (22 of 24 tagged fish movement detected >2 days post-tagging, ≤8% mortality). Our results indicate that minimizing air exposure should be advocated as part of guidelines for C&R for golden dorado. Our study also revealed that impairment of the equilibrium reflex is useful for anglers as an indicator for golden dorado vitality and potential need for monitoring recovery prior to release.

Peixes ictiófagos têm alta exigência dietética em proteína e, consequentemente, as dietas para estas espécies encontram-se entre as mais caras no mercado de alimentos para animais. O objetivo deste trabalho foi determinar o ponto de máximo lucro na substituição de farinha de peixe por farelo de soja das dietas para a produção de juvenis de dourado Salminus brasiliensis. Grupos de 12 juvenis da espécie (8,97±0,33g) foram estocados em tanques de 500 L em circuito fechado de circulação de água em um delineamento experimental aleatório (n=4), e alimentados até saciedade aparente em duas refeições diárias por 100 dias com rações extrudadas isoproteicas (39% proteína digestível) e isoenergéticas (3900 kcal energia digestível), contendo níveis graduais de substituição de farinha de peixe [FP] por farinha de soja [FS] (100% FP, 80% FP, 60% FP, 40% FP, 20% FP, 0% FP). Os índices de desempenho dos peixes foram analisados pelo método de maximização de lucro, considerando-se os preços por kg de venda do dourado (R$ 20,00), do FS (R$ 1,14) e da FP (R$ 3,50). O percentual de farinha de peixe nas dietas que maximiza o lucro foi de 83,51%. = Carnivore fish have high dietary protein requirement, and consequently diets for these species are among the most expensive in the feed market. The objective of this study was to determine the point of maximum profit for the replacement of dietary fishmeal by soybean meal in the production of Salminus brasiliensis juveniles. Groups of 12 juveniles of the species (8.97 ± 0.33 g) were stocked in 500-L tanks in a closed water circulation system. It was a randomized experimental design (n = 4), and being fed to apparent satiation in two daily meals per 100 days with isoproteic (39% digestible protein) and isoenergetic (3900 kcal digestible energy), extruded feeds, containing gradual levels of substitution of fishmeal [FP] by soybean meal [FS] (100% FP, 80% FP, 60 % FP, 40% FP, 20% FP, 0% FP). The performance indexes of fish were analyzed by the profit maximization method, considering the sales prices per kg of dourado (R$ 20.00), of FS (R$ 1.14) and of FP (R$ 3.50). The percentage of dietary fishmeal diets that maximized profit was 83.51%.

The predator-prey relationships between juvenile Nile Tilapia Oreochromis niloticus and native fish species of the Paraná River basin, Brazil, were experimentally examined. Juveniles of O. niloticus were offered to three native predator species (Salminus brasiliensis, Pseudoplatystoma corruscans, and Brycon orbignyanus) in 2,000-L tanks with four levels of habitat complexity (0%, 50%, 100% and RD (rocks and driftwood)). Predator efficiency was more variable among species (S. brasiliensis consumed 86.6% of the prey, P. corruscans 22.5% and B. orbignyanus 18.3%) than among levels of habitat complexity, and S. brasiliensis was faster than the others in detecting and consuming the prey. The higher predatory efficiency observed for S. brasiliensis can be partially explained by its more aggressive behavior (it fed earlier and for longer) and its presence in the surface layer. Here, the presence of predators led to O. niloticus juveniles spending more time at the surface or remaining in schools to coexist at the bottom with the predators, as expected for cichlids under predatory pressure in natural environments. Our results suggest that preserving and restoring populations of S. brasiliensis (and also to some extent P. corruscans and B. orbignyanus) might help to control O. niloticus in the Paraná River basin. RESUMO As relações predador-presa entre alevinos de Tilápia-do-Nilo Oreochromis niloticus e espécies de peixes nativos da bacia do rio Paraná, Brasil, foram examinadas experimentalmente. Dez alevinos de O. niloticus foram oferecidos a três espécies nativas de predadores (Salminus brasiliensis, Pseudoplatystoma corruscans e Brycon orbignyanus) em tanques de 2000L com quatro níveis de complexidade ambiental (0%, 50%, 100% e RD (rochas e galhos)). A eficiência predatória foi mais variável entre espécies (S. brasiliensis consumiu 86,6%, P. corruscans 22,5% e B. orbignyanus 18,3% dos alevinos) do que para complexidade ambiental, e S. brasiliensis foi mais rápido do que os outros em detectar e consumir a presa. A eficiência predatória de S. brasiliensis pode ser parcialmente explicada pelo seu comportamento mais agressivo (alimentou-se mais cedo e por mais tempo de experimento) e pela presença na área de superfície. A presença de predadores levou os alevinos de O. niloticus a passar mais tempo na superfície ou formar cardume para coexistir no fundo com os predadores, como o esperado para ciclídeos sob pressão predatória no campo. Nossos resultados sugerem que preservar e restaurar as populações de S. brasiliensis (principalmente, mas também P. corruscans e B. orbignyanus) podem ajudar no controle de O. niloticus na bacia do rio Paraná.

We investigated whether the movement and distribution of the migratory fish, Salminus brasiliensis, were affected by a small reservoir. We also examined how movement and distribution were related to water temperature, flow, and rainfall. In December 2011 and January 2012, 24 individuals were captured downstream from the dam, tagged with radio transmitters and released in the reservoir (5.46 km² total area). After being released in the reservoir, 18 of the 24 tagged fish travelled upstream, taking an average of 16.6 days to leave the reservoir, with daily movements varying from < 5 km/day to > 24 km/day. However, only seven tagged specimens (29.16%) returned to the lower reservoir section, while the rest remained in the intermediate and upper reservoir sections. Longitudinal distributions and movements were positively related to both upstream flow into the reservoir and water temperature. We found evidence that S. brasiliensis can recognize the longitudinal gradient and is able to continue its upstream migration. On the other hand, the reservoir negatively affected downstream movements, possibly because disorientation prevented movement to the lower reservoir section. Based on these results, we suggest that the impact of small reservoirs on migratory fish species should be objectively addressed in environmental impact assessments and management programs. RESUMO Neste estudo investigamos se o movimento e distribuição do peixe migrador, Salminus brasiliensis, são afetados por um pequeno reservatório. Também avaliamos como movimento e distribuição se relacionam com a temperatura da água, fluxo e pluviosidade. Em dezembro de 2011 e janeiro 2012, 24 indivíduos foram capturados a jusante da barragem, marcados com radiotransmissores e liberados no reservatório (5,46 km²). Depois de soltos, 18 dos 24 peixes marcados se deslocaram para montante, levando em média 16,6 dias para ultrapassar o reservatório com movimentos diários variando de < 5km/dia a > 24km/dia. Entretanto, apenas sete (29,16%) dos peixes marcados retornaram para seção inferior do reservatório, a maior parte mantendo-se nas seções intermediárias e superiores do reservatório. Distribuição longitudinal e movimento dos peixes foram relacionados positivamente com o fluxo de montante dentro do reservatório e com a temperatura da água. Assim, encontramos evidências que S. brasiliensis pode reconhecer o gradiente longitudinal e continuar sua migração ascendente. Por outro lado, nossos resultados também indicam que o movimento para jusante foi afetado, possivelmente, devido à desorientação, o que impede que os indivíduos alcancem as seções inferiores do reservatório. Com base nos resultados, sugerimos que impactos sobre peixes migratórios devem ser objetivamente abordados em avaliações ambientais e gestão ambiental de pequenos reservatórios.

Identifying spawning and recruitment areas of Neotropical migratory fish is an important conservation issue, because it allows to define connectivity between habitats used during the initial life cycle of these species. In this sense, the objective of this study was to delimit spawning and recruitment areas of three migratory fish (Megaleporinus obtusidens, Salminus brasiliensis and Prochilodus lineatus) along of an altitude gradient of the Uruguay River. Samplings of ichthyoplankton and juveniles were applied with five different fishing devices in four river stretches, one in reservoir and three in a free section, for two consecutive years (2015-2016 and 2016-2017), during the reproductive period of the species. Larvae and juveniles were not collected in the reservoir and, in the free section, larvae in the early stages of development were found only at an intermediate stretch, and the most larvae at more advanced stages (~80%) and juveniles (~95%) were recorded in the lower sampling stretch. Based on the larval stage and abundance of juveniles, spawning-recruitment connectivity sections were presumed for these migratory species. After, these sections were associated to the location of future hydroelectric dams in the study area, with possible negative implications for the conservation of these populations in the Uruguay River

The objective of this study was to evaluate the efficiency of Laser-Induced Breakdown Spectroscopy (LIBS) to detect the presence of bioaccumulated Fe and Pb in scales of Salminus brasiliensis and Prochilodus lineatus, and to compare the results from this technique with those obtained using the conventional atomic absorption spectrometry technique. The study used fish collected in the Amambai River, Upper Parana River, Brazil. The LIBS technique detected the presence of Fe in S. brasiliensis scales and Fe and Pb in P. lineatus scales on different regions. Using atomic absorption spectrometry, we verified a significant difference in Fe concentration in scales between the species analyzed, with a higher concentration in S. brasiliensis than in P. lineatus (p = 0.0004). Pb was not detected using atomic absorption spectrometry in either species because the concentration of this element was below the limit of detection of this technique. The LIBS technique was efficient in detecting Fe and Pb in scales of the two species analyzed, proving to be a promising tool for environmental monitoring.

The dourado, Salminus brasiliensis, a large, carnivorous, Neotropical, Characin, is highly regarded for fish farming and sport fishing alike. However, studies on the farming and husbandry of dourado are still scarce. This study evaluated the performance of dourado fed diets formulated so as to contain increasing levels of poultry by-product meal as a replacement for fish meal and aimed to identify the maximum level of replacement to maximize profit. The trial was set up in a closed recirculation system with controlled water quality (temperature 27 °C, dissolved oxygen 6.5 mg L−1, pH 7.4, and ammonia 0.25 mg L−1). Juvenile fish were stocked in tanks in a completely randomized design, acclimatized to system conditions and experimental diets, and then fed twice a day for 66 days with extruded, nutritionally complete diets (40 % digestible protein and 4020 kcal kg−1 digestible energy), formulated to contain 0, 20, 40, 60, 80 or 100 % poultry meal as a surrogate protein source for fish meal. Performance parameters – average weight gain, specific growth rate, feed consumption, feed conversion rate, protein efficiency rate, productive value of protein, energy retention rate, survival rate – did not differ (p > 0.05). To minimize the effects of influential data, the robust regression method was used and profit maximization analysis revealed that replacing 33.3 % of dietary fishmeal by poultry by-product meal maximizes profit in the farming of dourado.

Salminus is a genus composed of four species of migratory fishes and top predators. Although this group has great economic and ecological importance, the species level diversity of Salminus is not yet completely clarified. Our goal was to detect if this taxonomic problem is the consequence of lineage divergence within species, and, if so, whether these divergences are sufficient to flag potentially undescribed taxa. We employed the standard DNA barcoding analyses and a generalized mixed Yule-coalescent model (GMYC) using one mitochondrial (COI) marker and Bayesian Inference (BI) reconstruction for one nuclear (RAG2) marker for all currently recognized species of Salminus, sampled across different hydrographic basins. Eight MOTUs (Molecular Operational Taxonomic Units) were determined by distance and model-based analyses, and recovered with BI analyses for COI. Only Salminus affinis and Salminus franciscanus formed monophyletic haplogroups. Salminus brasiliensis and Salminus hilarii had two and four distinct mitochondrial lineages, respectively, and higher intraspecific K2P distances than the adopted optimum threshold. The RAG2 gene tree supported two lineages of S. hilarii (S. hilarii Amazon and S. hilarii Araguaia), while the other mitochondrial lineages of S. hilarii and S. brasiliensis were not supported. All lineages of both species, corresponded to morphological variation described in previous studies. We suggest, based on the DNA barcoding analysis, a new taxonomic scenario and conservation polices for Salminus in the Brazilian territory.

The dourado, Salminus brasiliensis (Cuvier, 1816) is a freshwater piscivorous Characin native to South American rivers. Owing to the high quality of its flesh and its fast growth, it is the object of both capture fisheries and fish farming. However, very little is known about the endocrine regulation of feeding and metabolism of dourado. In this study, cDNAs for orexin, CART and CCK were isolated in dourado, and their mRNA tissue distributions examined. In order to assess the role of these peptides in the regulation of feeding of dourado, the effects of fasting and feeding on mRNA expression levels of orexin, CART and CCK in the brain as well as CCK in the intestine were assessed. Whereas orexin and CCK have widespread mRNA distributions in the brain and peripheral organs, CART seems to be mostly limited to the brain. Orexin brain expression increased with fasting and displayed periprandial changes, suggesting it is involved in both long- and short-term regulation of feeding and appetite. CART and CCK hypothalamic expressions were not affected by fasting, but displayed periprandial changes with post-feeding decreases, suggesting roles in short-term satiation. CCK expression in the anterior intestine was not affected by fasting and did not display periprandial changes. Overall, our results suggest that orexin, CART and CCK are involved in the physiology of feeding of dourado.

Isolation-by-distance is recognized as a useful model for describing the spatial distribution of gene frequencies depending on dispersal characteristics of the species under study. However, some species may have populations that occupy the same geographic distribution during the breeding season yet reproduce at different time periods resulting in isolation-by-time (IBT). IBT may complicate investigations of spatial population structure if samples are obtained from multiple discrete time periods or may remain undiscovered if surveys are conducted with limited temporal scope. IBT has been observed in several studies of anadromous fishes (primarily salmon) as well as a few examples in taxa such as frogs, plants, birds and insects, but has not been rigorously tested in freshwater fishes. In this study, we assessed spatial and temporal genetic variation and tested for IBT in Dourado (Salminus brasiliensis), a large and commercially-important potamodromous fish species found in multiple river basins of South America. Using 11 polymorphic microsatellite loci, we estimated genetic differentiation of 317 adult Dourado collected monthly during the breeding season at three locations along the Uruguay River in southern Brazil. Analyses identified three populations that were clustered in time (i.e. early, middle and late), suggesting an IBT pattern of population structure with no significant spatial structure. Our results contribute to the mounting evidence across a wide range of taxa that suggests IBT may be more common that currently considered, even for species with very high dispersal capabilities such as potamodromous fishes.

The life cycle of Neocladocystis intestinalis (Vaz, 1932) was resolved experimentally. The prosobranchiate snail Aylacostoma chloroticum Hylton Scott (Thiaridae) collected in the Yacyretá Dam, Province of Misiones, Argentina, was found naturally infected with cercariae that possessed pigmented eye spots, 7 pairs of penetration glands, 12 pairs of flame cells, and a V-shaped, or Y-shaped excretory vesicle with very short stem. The cercariae developed in oval cysts, which were found on fin rays, and under scales of naturally and experimentally exposed tetragonopterid fish species and of experimentally exposed poecilid and prochilodont fish species. Adults were obtained experimentally from juvenile Salminus brasiliensis (Characidae), bred in captivity, and infected with metacercariae from albino Gymnocorymbus ternetzi (Tetragonopteridae), which had been exposed to emerging cercariae.

Besides being a dietary source of essential nutrients, colostrum contains important biologically active molecules. This study investigated enteric, muscle and hepatic tissue development of juvenile dourado Salminus brasiliensis fed with diets containing 0, 10 or 20 % of lyophilized bovine colostrum (LBC). Juveniles (13.3 ± 0.9 g; 10.8 ± 0.3 cm) were distributed into 18,300-L cages and fed with experimental diets for 30 or 60 days. Insulin-like growth factor type I (IGF-I) serum concentration and total protein (TP), DNA, RNA concentration in the intestine, muscle and liver of fish were assessed. The consumption of diets containing LBC did not influence IGF-I concentration, regardless of the presence of LBC in the diet and tissue IGF-I content was higher at 60 days. Furthermore, the indicators of intestinal and muscular cellular activity were not influenced by LBC consumption. Regardless of this result, between periods, muscle RNA and RNA/DNA was lower at 60 days, while TP/RNA was higher in the same period. Interaction between diet and period influenced concentration of the liver DNA: 0 > 10 > 20 % LBC at 30 days, while 0 = 10

Summary Salminus brasiliensis, a characin regionally named ‘dourado’ (meaning goldfish), is the biggest characid fish, this species is cited in a list of fishes that are vulnerable. The goal of the present work was to try to identify, through AFLP technique to convert them into single locus markers (SCARs), in order to improve the sex identification in S. brasiliensis. Between possible sex-specific AFLP markers in this study, one male-specific were isolated (Les1) and converted into a SCAR marker. Les1 marker was confirmed sex-specific in all samples tested. A sex-specific DNA marker applicable to fish would be very useful for elucidating sex determination mechanism in fish.

Freshwater fish reproduce annually in environments that provide favourable conditions for spawning and larval survival and growth. Thus, the aims of this study were to use long-term larval density data to evaluate the temporal distribution of the dourado Salminus brasiliensis, its habitat use for larval development and the effects of environmental variables on reproduction. S. brasiliensis larvae were mainly recorded in October and January in the Ivinheima River, and higher densities of larvae, primarily in the preflexion and flexion stages, were captured in the river and backwater biotopes. Water level, dissolved oxygen and temperature were the primary variables affecting the density of larvae, and this species can migrate over 200km to reproduce in the Ivinheima River and its tributaries. Therefore, S. brasiliensis is reproducing annually, indicating favourable local conditions for migration and spawning, and exhibits differential use of biotopes for reproduction, including rivers and backwaters (spawning) and lagoons (refuge and growth). Therefore, considering that the dourado is a key species for conservation, ensuring its reproductive success means maintaining a balanced ecological structure.

The pollution from urban effluents discharged into natural waters is a major cause of aquatic biodiversity loss. Ecotoxicological testing contributes significantly to understand the risk of exposure to the biota and to establish conservation policies. The objective of the current study was to assess the toxicity of a river highly influenced by urban effluents (Atuba River, Curitiba city, Southern Brazil) to the early stages of development in four South American native fish species, investigating the consequences at the population level through mathematical modelling. The species chosen were Salminus brasiliensis, Prochilodus lineatus, Rhamdia quelen, and Pseudoplatystoma corruscans, ecologically important species encompassing different conservation statuses and vulnerability. The embryos were exposed from 8 to 96 h post fertilization to the Atuba River water, collected downstream of the largest wastewater treatment plant in the Metropolitan Region of Curitiba, and their survival rates and deformities were registered. The species S. brasiliensis and P. lineatus presented the highest mortality rates, showing high sensitivity to the pollutants present in the water. According to the individual-based mathematical model, these species showed high vulnerability and risk of extinction under the tested experimental conditions, even when different sensitivity scenarios of juveniles and adults were considered. The other two species, R. quelen and P. corruscans, showed a more resistant condition to mortality, but also presented high frequency and severity of deformities. These results emphasize the importance of testing the sensitivity of different Brazilian native species for the conservation of biodiversity and the application of models to predict the effects of pollutants at the population level.

ESPÍNOLA, Luis Alberto; DOMINGUES, Wladimir Marques; BENEDITO, Evanilde. Variaciones en el contenido de energía en músculos de Salminus brasiliensis en diferentes estados de desenvolvimiento gonadal en el área de influencia del reservatório de Manso, Mato Grosso, Brasil. Iheringia. Série Zoologia, Porto Alegre, v.18, n.1, p.143-147, 2008. In order to achieve effectiveness in conservation and management measures it is necessary to understand the origin and destiny of energy by which organisms compete in different environments. This study tested the hypothesis that there are differences in muscle energy content during the gonadal development of Salminus brasiliensis (Cuvier, 1816) in Manso Reservoir. Fish collections were carried out from October 2002 to September 2003. After biometry, muscle samples of all individuals were dried at 60ºC and dry weight calorie/gram was determined by acalorimetric pump. Condition factor and Gonad Somatic Relationship (RGS) were compared to caloric values. Significant differences were not detected for caloric values between males and females. However, caloric values of each sex were significantly different among stages of gonadal development. There are different tendencies between sexes for ripening individuals: energy content increases in females, while it remains the same in males. For both sexes, higher levels of energy occurred at the mature stage in relation to the other stages. Females presented better condition factor than males, with higher values for mature females and spent males. Females presented higher RGS than males in ripening and mature stages. Intraspecific differences in muscle energy content suggest that similar studies should take all stages of gonadal development into account for both sexes. Abiotic conditions of Brazilian water bodies can also conduct to alterations in fish issue energy concentrations. Studies of energy content should contribute especially to assess anthropogenic impact in aquatic environments, as well rational measures of resource exploitation Resumen: Para que las medidas de conservación y manejo sean efectivas es necesario el entendimiento del origen y destino de la energia por las cuales compiten los organismos en los diferentes ambientes. Con la hipótesis de que existen diferencias en la energía contenida em los músculos durante el desenvolvimiento gonadal de Salminus brasiliensis (Cuvier, 1816), fueron realizadas colectas entre octubre de 2002 a septiembre de 2003, en el reservatório del río Manso. Después de la obtención de los datos biométricos, de cada individuo se tomaron muestras de la musculatura, las cuales fueron secadas a 60oC y el contenido calórico (cal/g de peso seco) determinado en uma bomba calorimétrica. Los valores del factor de condición y de la Relación Gónada Somática (RGS) fueron comparados con los contenidos calóricos. No fueron identificadas diferencias significativas entre los valores calóricos de machos y hembras de S. brasiliensis. Sin embargo, se pudo constatar diferencias calóricas significativas en los diferentes estados de maduración gonadal tanto en machos como em hembras. Se observaron tendencias diferentes entre los sexos cuando las gónadas de los individuos se encontraban en maduración: para las hembras, la energía aumentó, mientras que para los machos ésta se mantuvo, indicando una mayor variación energética relacionada mas con la maduración gonadal que con el proceso de migración. En ambos sexos, el estado maduro mostró mayor contenido energético em relación con los demás estados. Los valores del factor de condición, para las hembras, fueron mayores que para los machos, siendo que los mayores valores fueron constatados para hembras maduras y para machos esgotados. La RGS fue más elevado para las hembras, que para los machos en los estados maduración y maduro. Se concluye que debido a las variaciones intraespecíficas asociadas a la maduración gonadal, es importante que se tenga información sobre todos los estados del desenvolvimiento gonadal, para ambos sexos. Las condiciones abióticas en que se encuentran los principales cuerpos de agua brasileños también pueden conducir a alteraciones en las concentraciones de energía presentes en los tejidos de los peces. Estudios sobre el uso de la energía pueden ser útiles a las evaluaciones de impacto, sobre todo en lo que respecta a las interferencias antrópicas en el medio acuático, así como a las medidas de administración racional de los recursos a ser explotados.

FEITOSA, Letícia Andrian; FERNANDES, Rodrigo; COSTA, Rodrigo Silva da; GOMES, Luiz Carlos; AGOSTINHO, Angelo Antonio. Parâmetros populacionais e simulação do rendimento por recruta de Salminus brasiliensis (Cuvier, 1816) do alto rio Paraná. Acta Scientiarum. Biological Sciences, Maringá, v. 26, no.3, p.317-323, 2004. Disponível em: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/1593/967 The dourado Salminus brasiliensis (Characidae) is caught in all types of fisheries conducted in the upper Paraná River. However, a decline has been observed in the quantity of S. Brasiliensis harvested in recent years. In this paper, we deal with simulation of yield per recruit, in order to evaluate ongoing fishery regulation. We expect to generate information that guides the conservation of this species. Data from the artisanal fishery were gathered from October 1986 to September 1988, in the city of Porto Rico. In that region, to catch the dourado , fishers use gillnets, hook and line, long lines and branch hooks. Simulations of yield per recruit were performed under diverse scenarios of fishing mortality and minimum size of capture, using the equilibrium model of Beverton and Holt, modified by Jones. Simulations showed increase in the yield per recruit when minimum sizes of capture were 60cm and 65cm, suggesting that a review of ongoing fishery regulation is needed. In addition, adjustments in dam operations during the spawning season of the species, and protection and prohibition of the fishery in nursery and spawning areas are suggested. O dourado Salminus brasiliensis é uma espécie explorada por todos os tipos de pesca na bacia do rio Paraná e sua captura tem sido diminuída nos últimos anos. Nesse contexto, o presente trabalho tem por objetivo simular o rendimento por recruta de S. brasiliensis partindo da necessidade de rever a regulamentação de pesca, na tentativa de conservar os estoques da espécie. Para realizar o trabalho, foram usados os dados de captura junto aos pescadores profissionais do município de Porto Rico, Estado do Paraná, no período de outubro de 1986 a setembro de 1988, amostrados com redes de espera, com linha e anzol, com espinhéis e com anzóis de galho. A simulação do rendimento por recruta foi realizada considerando diversos cenários de mortalidade por pesca e comprimentos mínimos de captura, a partir do modelo de rendimento de equilíbrio de Beverton e Holt, modificado por Jones. A simulação mostrou um incremento no rendimento por recruta para os comprimentos mínimos de 60 e de 65cm, sugerindo que mudanças na legislação em vigor devem ser consideradas. Além disso, sugerimos mudanças nos procedimentos operacionais das barragens, na época de reprodução da espécie, e proteção da pesca nos locais de desova e nos criadouros naturais. Abstract: The dourado Salminus brasiliensis (Characidae) is caught in all types of fisheries conducted in the upper Paraná River. However, a decline has been observed in the quantity of S. Brasiliensis harvested in recent years. In this paper, we deal with simulation of yield per recruit, in order to evaluate ongoing fishery regulation. We expect to generate information that guides the conservation of this species. Data from the artisanal fishery were gathered from October 1986 to September 1988, in the city of Porto Rico. In that region, to catch the dourado , fishers use gillnets, hook and line, long lines and branch hooks. Simulations of yield per recruit were performed under diverse scenarios of fishing mortality and minimum size of capture, using the equilibrium model of Beverton and Holt, modified by Jones. Simulations showed increase in the yield per recruit when minimum sizes of capture were 60cm and 65cm, suggesting that a review of ongoing fishery regulation is needed. In addition, adjustments in dam operations during the spawning season of the species, and protection and prohibition of the fishery in nursery and spawning areas are suggested.

Salminus brasiliensis (Cuvier, 1816) Fig. 6 Body deep; greatest depth contained 3.6 to 3.7, caudal peduncle depth 11.3 to 11.5 times in SL; head length 3.1 to 3.3, predorsal distance 1.8 to 1.9, caudal peduncle length 9.3 to 9.6 in SL; snout length 3.4 to 4.0, horizontal orbital diameter 5.7 to 5.9 and least interorbital width 2.7 to 3.2 in HL. Mouth terminal; inner row of premaxilla with 9-11, outer row with 8, inner row of dentary with 40-50, outer row with 28 or 29 and maxilla with 30-33 teeth. Lateral line with 93-96 pored scales; transverse series above lateral line with 16-18 scale rows and below with 8-9 scale rows. Dorsal fin with 11 or 12, pectoral fin with 15, pelvic fin with 9, anal fin with 26-29 and caudal fin with 19 rays. Ground color yellowish; longitudinal series of dark-brown spots on flank scales; dark-brown transverse band on posterior portion of caudal peduncle, extending to distal margin of median caudal-fin rays. Yellowish fins (Graça, Pavanelli, 2007). Maximum standard length. 780.0 mm (Graça, Pavanelli, 2007). Distribution. Río de la Plata and río Mamoré basins, and Laguna dos Patos drainage., Published as part of Ota, Renata Rúbia, Deprá, Gabriel de Carvalho, Graça, Weferson Júnio da & Pavanelli, Carla Simone, 2018, Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated, pp. 1-111 in Neotropical Ichthyology 16 (2) on page 25, DOI: 10.1590/1982-0224-20170094, http://zenodo.org/record/3678395, {"references":["Pavanelli CS, Graca WJ, Zawadzki CH, Britski HA, Vidotti AP, Avelino GS, Verissimo S. Fishes from the Corumba Reservoir, Paranaiba River drainage, upper rio Parana basin, State of Goias, Brazil. Check List. 2007; 3 (1): 58 - 64."]}

Four valid species are currently recognized in the Neotropical migratory genus Salminus: Salminus brasiliensis, Salminus franciscanus, Salminus hilarii and Salminus affinis. However, molecular evidence strongly suggested that two different species might be contained under the taxonomic denomination Salminus brasiliensis. Therefore, the geographical distribution of each entity was evaluated in order to understand their contribution to the different stocks of major river networks in South America. Major river networks of the La Plata River basin were explored to characterize the geographical distribution of the two genetic lineages. To characterize further the genetic partitioning within each lineage of S. brasiliensis, a haplotype analysis was conducted. The 5′ region of the mitochondrial COI gene was used as the molecular marker. In total, 45 fish samples of S. brasiliensis from 19 sites in Argentina, Brazil and Paraguay were sequenced. Additional COI sequences of S. brasiliensis, S. franciscanus and S. hilarii were gathered from public databases. All samples of S. brasiliensis comprised two different mitochondrial lineages. Accordingly, phylogenetic tree topologies segregated the complete set of sequences into two disparate clusters. One of these clusters was far closer phylogenetically to S. hilarii than to other S. brasiliensis. While one of the genetic lineages of S. brasiliensis seemed mostly restricted to the upper Paraná River, the other showed a widespread distribution along major river networks of the basin. Fifteen unique haplotypes were identified and collapsed. Salminus hilarii and S. franciscanus have private haplotypes. In S. brasiliensis, each mitochondrial lineage also hosts a set of unshared haplotypes. The sympatry of two different putative species within S. brasiliensis together with their unshared haplotypes present a difficult situation for management and conservation that calls for timely solutions. Fil: Rosso, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Rueda, Eva Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias. Departamento de Ciencias Naturales; Argentina Fil: Sánchez, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias. Instituto de Ictiología del Nordeste; Argentina Fil: Bruno, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - La Plata. Instituto de Genética Veterinaria Ing. Fernando Noel Dulout; Argentina Fil: Casciotta, Jorge Rafael. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina Fil: Aguilera, Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Almirón, Adriana Edith. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina Fil: Ruiz Diaz, Federico Jose. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias. Instituto de Ictiología del Nordeste; Argentina Fil: Cancino, Delia Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Bugeau, Horacio Baltazar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Mabragaña, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: González Castro, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Delpiani, Sergio Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Díaz de Astarloa, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

Submitted by RONALD RIBEIRO ALVES null (ronald.ribeiro@yahoo.com.br) on 2018-03-12T13:16:31Z No. of bitstreams: 1 tese ronald final.pdf: 952977 bytes, checksum: 4f649e858c5e7fa3f41f94db33fd43fa (MD5) Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-03-14T13:23:31Z (GMT) No. of bitstreams: 1 alves_rr_dr_bot.pdf: 952977 bytes, checksum: 4f649e858c5e7fa3f41f94db33fd43fa (MD5) Made available in DSpace on 2018-03-14T13:23:31Z (GMT). No. of bitstreams: 1 alves_rr_dr_bot.pdf: 952977 bytes, checksum: 4f649e858c5e7fa3f41f94db33fd43fa (MD5) Previous issue date: 2018-03-02 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Os processos migratórios realizados por diferentes espécies animais com finalidades tróficas ou reprodutivas tem despertado grande interesse por parte dos pesquisadores há várias décadas. Entre as espécies de grande importância nestes ambientes, Salminus brasiliensis (Cuvier, 1816) se caracteriza como um peixe migrador de ampla distribuição em território brasileiro, principalmente na bacia do Prata, constituída pelos rios Paraná, Paraguai e Uruguai, onde pode atingir grande tamanho. Assim, estudos que visam proporcionar melhores condições de manejo e sua conservação são muito importantes. Neste contexto, as alterações antropogênicas que afetam a espécie S. brasiliensis e a falta de informação que dificultam estratégias eficazes de manejo e conservação, o presente estudo teve como objetivo investigar a variabilidade genética e a estrutura genética das populações migratórias e residentes de S. brasiliensis da bacia do Rio Mogi Guaçu, a partir de amostragem realizada no período de 2008, 2009, 2010 e 2015, tendo como ferramenta a aplicação de técnicas de genética molecular. Os resultados obtidos indicaram altos níveis de variabilidade genética em todos os grupos amostrados, sendo que a heterozigosidade observada (Ho) variou de 0,59 a 0,67 e a heterozigosidade esperada (He) variou de 0,70 a 0,74. A Análise da Variância Molecular (AMOVA) revelou baixa estruturação genética em todos os grupos (FST = 0,0072), nas quais a maior fonte de variabilidade genética foi verificada entre os indivíduos (85,98%). No entanto, a análise de FST em pares mostrou diferenças sutis na variabilidade genética, uma vez que foi verificada uma variação de FST = 0,025; p

Heavy metals concentration in fishes are important indicator geomorphological or environmental integrity in aquatic habitats. Aiming to evaluate metal concentration in fish muscles in Apa River, upper Paraguay basin, we analyzed 124 individuals of eight fish species at Cachoeira do Apa district (Porto Murtinho) from 2013 to 2014 belonging to Brycon hilarii, Leporinus friderici, Megaleporinus macrocephalus, Megaleporinus obtusidens, Piaractus mesopotamicus, Prochilodus lineatus, Pterodoras granulosus and Salminus brasiliensis. The samples were frozen and in the laboratory the musculature was removed, the samples were digested using the triacid method, and later the concentration of heavy metals was quantified in a flame atomic absorption spectrophotometer. There is a significant difference in the concentration of metals in fish (F=27.79, pf studied species, we observed that P. lineatus have a more different pattern of metal concentration, with P. granulosus also presenting a different pattern of others species. None species presented the concentration of metals above the limit defined by Brazilian legislation, however, species differed in their metal concentrations according to the position in the water column and feeding, suggesting that the integrated assessment of the concentration of metals may be an indicator of ecological differences in the obtaining of resources by species in aquatic communities. DOI: http://dx.doi.org/10.17807/orbital.v10i1.1040

Aim: This paper is aimed at describing the changes of fish species in the middle and lower courses of the Tietê River, emphasizing rheophilic and invasive fish species as well as identifying the causes for such alterations. Methods Data collection consisted in: intense revision of publications, dissertations and thesis regarding the subject; information at the Zoology Museum at USP (MZUSP); revision in species identification through MUZUSP collection; historical survey of introduced species based on the literature and samplings in the years of 2000 and 2001. Results The main impacts identified in the Tietê River with consequence to the ichthyofauna were: domestic and industrial pollution, deforestation, damming, course rectification, silting and species introduction. From the 80 species identified in the study area, 28 were invasive. Many fish species have been introduced in the Tietê River since the late 19th Century with carpa (Cyprinus carpio) being the first one, followed by the introduction of black bass (Mycropterus salmonoides) at the beginning of 20th Century. Other species such as corvina (Plagioscion squamosissimus ) have been introduced by electricity companies, which has contributed to the species composition changes. Migratory species as dourado (Salminus brasiliensis ), pacú (Piaractus mesopotamicus) and pintado ( Pseudoplatystoma corruscans), which used to be abundant have become rare or absent after the construction of reservoirs, mainly because reservoirs in cascade have been built. Piracanjuba (Brycon orbignyanus), typically herbivore species, had its stock decreased due to the lack of ciliary vegetation and damming. Conclusions Following the building of the reservoirs there have been important alterations in the composition of ichthyofauna, leading to the nearly complete absence of migratory species and the prevalent species are the ones which adapted to the new conditions. In addition to the damming, lack of ciliary vegetation and pollution also caused alterations in the ichthyological community. Resumo Objetivo: Este trabalho descreve e busca identificar as causas de alterações na composição de espécies de peixes no Médio e Baixo rio Tietê, com ênfase nas espécies reofílicas e invasoras. Métodos Os dados foram obtidos através de uma intensa revisão de publicações, dissertações e teses realizadas na área de estudo, levantamento junto ao Museu de Zoologia da USP (MUZUSP), revisão na identificação das espécies através da coleção do MUZUSP, levantamento histórico de espécies introduzidas e espécies coletadas nos anos de 2000 e 2001. Resultados Os principais impactos identificados no rio Tietê com consequências para a ictiofauna foram: poluição doméstica, poluição industrial, desmatamento, represamentos, retificação do leito, assoreamento e introdução de espécies. Das 80 espécies de peixes identificadas na área de estudo, 28 são invasoras. Diversas espécies de peixes têm sido introduzidas no rio Tietê desde o final do século XIX, sendo a primeira a carpa comum (Cyprinus carpio), seguida pela introdução do black bass (Mycropterus salmoides) no começo do século XX. Outras espécies como a corvina (Plagioscion squamosissimus ) foram introduzidas por empresas do setor elétrico, o que contribuiu com a alteração da composição de espécies. As espécies migradoras como o dourado (Salminus brasiliensis), pacu (Piaractus mesopotamicus ) e pintado (Pseudoplatystoma corruscans) que antes eram abundantes se tornaram raras ou ausentes após a construção dos reservatórios, principalmente por se tratarem de reservatórios em cascata. A piracanjuba (Brycon orbignyanus), espécie tipicamente herbívora, teve seu estoque reduzido devido à falta de vegetação ciliar e os represamentos. Conclusões Após a construção dos reservatórios ocorreram profundas alterações na composição da ictiofauna, sendo que espécies migradoras se tornaram praticamente ausentes e as espécies que predominam são as mais adaptadas às novas condições. Além do represamento, a perda da mata ciliar e a poluição também causaram alterações na comunidade íctica.

Carbohydrate utilization by fish varies with feeding habits and feed processing. Extruded aquafeeds have increased digestibility of carbohydrate sources resulting from the cooking and gelatinization of this nutrient, making it readily available for all aquatic species. This study aimed at determining the effects of extrusion cooking of feeds in the digestibility of different dietary carbohydrate sources for dourado. Isonitrogenous and isoenergetic diets (530 g kg−1 crude protein and 20.80 MJ kg−1 gross energy) containing either corn, toasted cassava flour, wheat flour, broken rice, cassava starch, or corn starch, in extruded or pelletized form and added of chromic oxide as inert marker, were fed to groups of juvenile dourado (73.97 ± 12.0 g; n = 40) stocked in 500-L polyethylene tanks. Extrusion cooking improved the digestibility of energy and/or starch of corn, cassava starch, wheat flour, rice and corn starch (P 0.05). It is thus fair to infer that dourado, despite being a carnivorous species, is properly fit to digest wheat flour, rice and corn starch in natural form.