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Pleistocene climate changes were major historical events that impacted South American biodiversity. Although the effects of such changes are well-documented for several biomes, it is poorly known how these climate shifts affected the biodiversity of the Pantanal floodplain. Fish are one of the most diverse groups in the Pantanal floodplains and can be taken as a suitable biological model for reconstructing paleoenvironmental scenarios. To identify the effects of Pleistocene climate changes on Pantanal’s ichthyofauna, we used genetic data from multiple populations of a top-predator long-distance migratory fish, Salminus brasiliensis. We specifically investigated whether Pleistocene climate changes affected the demography of this species. If this was the case, we expected to find changes in population size over time. Thus, we assessed the genetic diversity of S. brasiliensis to trace the demographic history of nine populations from the Upper Paraguay basin, which includes the Pantanal floodplain, that form a single genetic group, employing approximate Bayesian computation (ABC) to test five scenarios: constant population, old expansion, old decline, old bottleneck following by recent expansion, and old expansion following by recent decline. Based on two mitochondrial DNA markers, our inferences from ABC analysis, the results of Bayesian skyline plot, the implications of star-like networks, and the patterns of genetic diversity (high haplotype diversity and low-to-moderate nucleotide diversity) indicated a sudden population expansion. ABC allowed us to make strong quantitative inferences about the demographic history of S. brasiliensis. We estimated a small ancestral population size that underwent a drastic fivefold expansion, probably associated with the colonization of newly formed habitats. The estimated time of this expansion was consistent with a humid and warm phase as inferred by speleothem growth phases and travertine records during Pleistocene interglacial periods. The strong concordance between our genetic inferences and this historical data could represent the first genetic record of a humid and warm phase in the Pantanal in the period since the Last Interglacial to 40 ka.

This study aimed at assessing the sperm quality of the Amazon catfish, Leiarius marmoratus ¸ after refrigeration without extenders. After capturing the animals and stripping of semen, the following parameters were analyzed: progressive motility, motility quality score, duration of motility and sperm morphology. An aliquot of fresh semen from each male was kept at room temperature (28 ± 2°C) as a control, for further comparison with cooled semen. The semen from each animal was stored in extenders-free individual syringes. The syringes were kept in ice within polystyrene boxes at 13 ± 2°C. For both fresh and cooled semen, seminal parameters were evaluated every one-hour interval, reaching seven hours of analysis. Fresh semen showed a significant decrease in motility, motility quality score and duration of motility remaining viable only for three hours. Progressive motility of the cooled semen displayed a negative linear pattern (P0.05), even though the mean values of total abnormalities have increased over the storage time. Further studies focusing on the application of this technique should be performed, including the addition of extenders and cryoprotectants for preservation of the sperm over longer periods.

Breeding values, the differences in responses to selection, the (co)variance components and genetic parameters of the morphometrics traits of Nile tilapia (O. niloticus) reared in cages were estimated. Morphometric and performance traits of 1824 animals were analyzed. The estimated heritability ranged from 0,08541 to 0,194 and the proportion of the variation due common environ-mental/hatchery and nursery effects ranged from 0,07402 to 0,1586 and 0,00087 to 0,079, respectively. The values of genetic correlations and ranking indicated a strong association between genetic traits. The largest genetic gains were for weight and daily weight gain, and the best response to indirect selection was checked for weight. Selection for growth rate led to genetic gain in morphometric traits.

O mercado global de alimentos tem experimentado expansão sem precedentes e mudança nos padrões alimentares, tornando-se mais homogêneo e globalizado. O Brasil tem grande potencial para a aquicultura, pelas condições naturais, pelo clima favorável e pela sua matriz energética. Este potencial está relacionado à sua extensão costeira de mais de oito mil quilômetros, à sua zona econômica exclusiva (ZEE) de 3,5 milhões de km² e à sua dimensão territorial, que dispõe de, aproximadamente, 13% da água doce renovável do planeta. Prefácio.

O objetivo deste trabalho foi estimar as herdabilidades e a estrutura de correlações genéticas entre as características de desempenho de tilápia-do-nilo (Oreochromis niloticus) da linhagem GIFT, em diferentes estágios do ciclo de produção. As tilápias foram cultivadas em tanques-rede. Mediu-se ganho em peso diário total, peso vivo e ganho em peso diário, em quatro períodos, com intervalos de aproximadamente 30 dias. Foram realizadas análises unicaracter para as medidas, em todas as biometrias e, nas análises bicaracter, as medidas de mesma característica foram combinadas duas a duas e com o ganho em peso diário total. As estimações de herdabilidade variaram de 0,15 a 0,11 para peso vivo, 0,16 a 0,09 para ganho em peso diário e 0,17 a 0,12 para ganho em peso diário total, nas análises unicaracter. Os valores estimados de correlação genética para peso vivo e ganho em peso diário, associados ao ganho em peso diário total, variaram entre 0,37 a 0,98 e 0,74 a 0,88, respectivamente. A forte associação genética estimada entre peso vivo em biometrias intermediárias e ganho em peso diário total sugere que a seleção para velocidade de crescimento pode ser realizada de forma precoce. The objective of this work was to estimate the structure and heritability of genetic correlations between the performance traits of Nile tilapia (Oreochromis niloticus) of the GIFT lineage during different stages of the production cycle. The Nile tilapias were grown in net cages. Daily total weight gain, live weight, and daily weight gain were measured in four periods, in approximately 30-day intervals. One-trait analyses were performed for all biometric measurements, and, in the two-trait analyses, measurements of the same traits were combined in pairs and to daily total weight gain. Estimated heritabilities ranged from 0.15 to 0.11 for live weight, from 0.16 to 0.09 for daily weight gain, and from 0.17 to 0.12 for daily total weight gain in the one-trait analyses. Estimated values of genetic correlation for live weight and daily weight gain, associated with daily total weight gain, ranged from 0.37 to 0.98 and from 0.74 to 0.88, respectively. The high genetic correlation estimated between live weight in intermediate biometric measurements and daily total weight gain suggests that selection for growth rate may be performed earlier.

a b s t r a c t Flood pulse and biotic interrelationships control the food web dynamics of river floodplain systems. The Pantanal Plain in the Paraguay River Basin (Brazil) occupies 140,000 km2 of periodically flooded areas and is divided into 12 subregions with different characteristics related to the flood pulse duration, the vegetation, the type of soil, and the resources used in activities, particularly fishing. In this study, we used Ecopath with Ecosim (EwE) to model three oxbow lakes in the South Pantanal Plain, where there is no fishing activity, to test the similarity of the ecosystems, to identify the keystone species and the types of food web controls, and to determine whether these environments can support moderated fishing pressure. We found that the food webs of the oxbow lakes are similar to each other because, although they depend mainly on the presence or absence of predators, flood pulses similarly homogenize the lakes. The results highlight the importance of detritus in these food webs. In addition, the highest values of the keystoneness species index in the three models highlight the role of top predators (Hoplias malabaricus, Serrasalmus spp., Pseudoplatystoma reticulatum, birds, and mammals). Therefore, we suggest that the food webs in the three systems are subjected to an alternated control process: detritus controls the food web during the flood season and by the top predators during the dry season. The simulation outputs indicate that these oxbow lakes can sustain only moderate fishing because increasing the fishing pressure reduces the biodiversity and can negatively impact the top predators.

Pacu (Piaractus mesopotamicus) is an important fish species for professional and sport fisheries in the Alto-Paraguay Basin, located in the central western Brazil. In this study the D-loop control region of mtDNA sequence data was used to investigate genetic variability within and among populations of pacu. A total of 99 individuals were collected in the Paraguay River and in four other main tributaries. From these, 27 different haplotypes were observed. The overall nucleotide diversity and haplotype diversity were high in all sampling sites with 0.013 ± 0.001 and 0.840 ± 0.035, respectively. Hierarchical AMOVA analysis showed that pacu populations form a single panmictic population with low ΦST = −0.0012 (p = 0.486) and high gene flow among rivers. Despite high genetic variability, the total capture officially landed in the Upper-Paraguay River Basin has been decreasing steadily during the last years with indications of overexploitation. Taking into account the heterogeneity of habitats, continuous anthropogenic disturbances and lack of genetic structure, it appears that fish from these sampling sites function as a metapopulation, a framework that may be applied to long term fishery management of pacu in the Panatanal.

The "tucunaré", Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the "tucunaré" could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.

Limnoperna fortunei (Bivalvia, Mitylidae) was introduced into South America in 1991 in the La Plata River (Argentina). It arrived in the ballast water of ships coming from Asia, where this species is native. It was first observed in 1998 in the Paraguay River. Limnoperna was introduced into the Pantanal region as hull fouling of vessels using the Paraguay–Parana waterway. This study describes how L. fortunei came to the Pantanal region, and provides details of its occurrence, density, and impacts. From 1999 to 2002, observations and sampling on natural and artificial substrates in the Paraguay River were made. Some aspects of the spread and impacts, based on local community information, were also analyzed. On artificial substrate the density reached 523.8 individuals m−2 and on natural substrate (rocks), up to 10,000 individuals m−2 were found. The densities observed were quite low compared to those found in Southern Brazil, where values up to 100,000 individuals m−2 have been recorded in the last 3 years. In the Paraguay River, the population density of L. fortunei can be negatively impacted by periodic low levels of dissolved oxygen and decreases in pH to between 5 and 6. Such conditions are frequently present during the periodic flooding or inundation of this area. Under these conditions, a high mortality of L. fortunei was recorded in March of 2002, on both natural and artificial substrates. Despite low densities, L. fortunei can colonize water cooling systems of boats, obstructing water circulation and causing motor overheating. Accumulation in water supply equipment, such as pumps and pipes has also been observed.

Made available in DSpace on 2022-04-29T07:14:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-01 The Pantanal Biosphere Reserve contains one of the highest concentration of animal species in the Neotropics, including about 300 fish species living in diverse environments associated with wetlands in the upper Paraguai River basin. This biome spans portions of Bolivia, Brazil and Paraguay and includes the Parque Nacional do Pantanal Matogrossense (PNPM), a region of the Pantanal which has been assigned as high conservation priority in Brazil. This study reports the results of an ichthyological survey within the PNPM, where samples were taken at 12 sites during the dry season in 2001, 2010 and 2011. We record 182 species representing three classes, 10 orders and 41 fish families. We report the first occurrence of the genus Anchoviella (order Clupeiformes), in the La Plata basin. This survey will provide information for future studies concerning conservation and management plans for the PNPM as well as for the Pantanal, which is one of the largest permanent wetland areas in the world and among the most unique and important South American biomes. © 2014 Check List and Authors. Universidade de São Paulo Escola de Engenharia de São Carlos Centro de Recursos Hídricos e Ecologia Aplicada, Rod. Domingos Innocentini, 292, CEP 13566-590, São Carlos, SP Centro Nacional de Pesquisa e Conservação de Peixes Continentais Instituto Chico Mendes de Conservação da Biodiversidade, Rod. SP 201, CEP 13630-000, Pirassununga, SP Universidade Estadual Paulista Instituto de Biociências Departamento de Morfologia, Rubião Jr. s/n, CEP 18618-970, Botucatu, SP Empresa Brasileira de Pesquisa Agropecuária Embrapa Pantanal, 79320-900 Corumbá, MS Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, no 2367, Bairro Boa Esperança. CEP 78060-900, Cuiaba, MT Parque Nacional do Pantanal Matogrossense Instituto Chico Mendes de Conservação da Biodiversidade, Caixa Postal 8005, Zona Rural de Poconé MT, CEP 78048-960, Cuiaba, MT Universidade Federal de São Carlos, Rod. João Leme dos Santos SP-264, Itinga, CEP 18052-780, Sorocaba, SP Universidade Estadual Paulista Instituto de Biociências Departamento de Morfologia, Rubião Jr. s/n, CEP 18618-970, Botucatu, SP

The aim of this work was to analyze the genetic diversity in three GIFT tilapia generations from the Genetic Improvement Program of State University of Maringa, using the RAPD marker. One hundred eighty fin samples were used. The seven primers used produced 91 fragments, of which 98.9% were polymorphic. Differences (p < 0.05) were observed in the frequency of 64 fragments, of which ten were excluded in G2. The results of genetic variability estimated by the Shannon index (G0: 0.430, G1: 0.469 and G2: 0.420) and by the percentage of polymorphic fragments (G0: 90.1%, G1: 94.5% and G2: 86.8%) indicated a high intrapopulation genetic variability, corroborated by the Nei genetic diversity results that showed G1 with the highest values (G0: 0.281, G1: 0.307 and G2: 0.277). A greater genetic distance between the G0 and G1 generations (0.108) and a greater genetic identity between G0 and G2 (0.909) were verified. Intrapopulation genetic diversity was high in the three generations, with highest values in G1.

This paper describes eight polymorphic microsatellite loci of the large migratory catfish Jau, Zungaro jahu, a threatened species in the Paraguay—Parana River Basin, which includes the Brazilian wetland Pantanal system. The number of detected alleles varied from 3 to 10, while observed and expected heterozygosity values ranged from 0.3182 to 0.8333 and 0.3298 to 0.8652, respectively. Cross-amplification on five related species was successfully evaluated. These isolated markers demonstrated to be very useful for population studies of this fish and related species, consisting in important tools for evaluations related to the management and conservation of the native populations.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:42:18Z No. of bitstreams: 1 S1519-69842006000200014.pdf: 188940 bytes, checksum: ea836108ce57a6c5995062ebd5896519 (MD5) Made available in DSpace on 2013-08-22T18:42:18Z (GMT). No. of bitstreams: 1 S1519-69842006000200014.pdf: 188940 bytes, checksum: ea836108ce57a6c5995062ebd5896519 (MD5) Previous issue date: 2006-02-01 Made available in DSpace on 2013-09-30T19:29:22Z (GMT). No. of bitstreams: 2 S1519-69842006000200014.pdf: 188940 bytes, checksum: ea836108ce57a6c5995062ebd5896519 (MD5) S1519-69842006000200014.pdf.txt: 19242 bytes, checksum: cfaa20885c6f91a8b31b395777d408c7 (MD5) Previous issue date: 2006-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:04Z No. of bitstreams: 2 S1519-69842006000200014.pdf: 188940 bytes, checksum: ea836108ce57a6c5995062ebd5896519 (MD5) S1519-69842006000200014.pdf.txt: 19242 bytes, checksum: cfaa20885c6f91a8b31b395777d408c7 (MD5) Made available in DSpace on 2014-05-20T15:08:04Z (GMT). No. of bitstreams: 2 S1519-69842006000200014.pdf: 188940 bytes, checksum: ea836108ce57a6c5995062ebd5896519 (MD5) S1519-69842006000200014.pdf.txt: 19242 bytes, checksum: cfaa20885c6f91a8b31b395777d408c7 (MD5) Previous issue date: 2006-02-01 Informações sobre o ciclo reprodutivo de espécies exploradas pela pesca são imprescindíveis para o seu manejo adequado. O tamanho de início da atividade reprodutiva do Pinirampus pirinampu (Spix, 1829) foi determinado. Os exemplares foram capturados em setembro, outubro e dezembro de 1997 e fevereiro e março de 1998. O estádio de desenvolvimento gonadal foi identificado macroscopicamente. O índice gonadossomático médio (IGS), calculado mensalmente, foi utilizado como indicador da época de desova. Para determinação do comprimento da primeira maturação gonadal agruparam-se, separadamente, machos e fêmeas por classes de comprimento em imaturos e adultos. Os resultados referentes aos indivíduos adultos foram lançados em gráficos e a mediana correspondeu à estimativa do comprimento no qual 50% dos indivíduos atingem a maturidade (L50). Foi também determinado o L100, estimativa do comprimento em que todos os indivíduos estão aptos à reprodução. Machos e fêmeas em processo de maturação gonadal foram encontrados a partir de outubro, com maior freqüência em fevereiro, e, somente a partir deste mês, foram encontrados indivíduos com gônadas esvaziadas. O índice gonadossomático mostrou que a partir de setembro inicia-se o processo de desenvolvimento gonadal, com seu valor máximo em fevereiro. O L50 para fêmeas foi 574 mm e para machos foi 536 mm. O L100 para fêmeas foi 590 mm e para os machos, 580 mm. Information regarding the reproductive cycle of commercially exploited fish species is extremely important for their appropriate management. The reproductive size of Pinirampus pirinampu (Spix, 1829) was determined for a population studied in the Pantanal wetlands of western Brazil. Samples were taken in September, October, and December 1997, and in February and March 1998. Gonadal stages were macroscopically determined and a monthly gonadossomatic index (GSI) was used to determine the breeding period. The length of the first gonadal maturation was determined by classifying male and female adults and immature fish into length classes. The data on the adult individuals were plotted on graphs and the median values estimated to find the length at which 50% of the individuals reached maturity (L50). L100 was also determined. Males and females in the gonadal maturation process were recorded from October on, and the highest frequency was found to occur in February. Individuals with empty gonads occurred from February onwards. The GSI showed that gonadal development began in September and reached its peak in February. The L50 was 574 mm for females and 536 mm for males, while the L100 was 590 mm for females and 580 mm for males. UNESP Department of Ecology University of Mato Grosso School of Veterinary Medicine Department of Animal Production Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) CPAP UNESP Department of Ecology

The objective of this work was to estimate the (co)variance and the genetic parameters for weight and average daily gain from two national generations of the GIFT strain of the Nile tilapia ( Oreochromis niloticus ). We evaluated 3918 fish from two generations of the breeding program from the Universidade Estadual de Maringa, Northwestern Parana. Univariate and bivariate analysis were carried out using Bayesian inference. The estimates of heritability using one-trait models for weight was 0.15, average daily gain was 0.19, fish length was 0.23, fish width was 0.19, standard length was 0.17, fish height was 0.15, and the head length was 0.17. The genetic and phenotypic correlations were above 0.68 and 0.95, respectively. The values of Spearman and Pearson correlations for breeding values of the morphometric traits in relation to average daily gain ranged from 0.58 to 0.98 and from 0.63 to 0.99, respectively. In the second generation (G2), the genetic gain was 2.6%, the effective size of the population was 94, and the inbreeding coefficient was 0.005. In the next generation (G3), these values were 8.1%, 124 and 0.004, respectively. The genetic gains over the generations gradually increased from one generation to another, indicating that the criterion, average daily gain, chosen for feature selection was efficient.

This chapter contrasts different approaches to assessment of the costs and benefits of the development of the Hidrovia, with emphasis on potential impacts on the Pantanal, and on implications for decision-making of using the information derived from these different approaches. We begin by illustrating the relationship of the flood/drought cycle, to its extremely rich biodiversity, and its importance to the human economy. We then show how both are vulnerable to small changes in water levels that could be brought about by development of the Hidrovia, and the cumulative impacts of other development that would be supported by it. The costs and benefits of these and other changes are difficult to value because they are related to conflicting social objectives, including geopolitical considerations, diverse stakeholder perspectives, and to goods and services with significant non-market and subsistence values. Also, given the complexity of the problem and inherent uncertainty, attempts to analyze costs and benefits all rest on questionable and often arbitrary assumptions, and depend on the interests and perspectives that have a voice in the decision-making process, and on how the problem is defined. In new kinds of complex problems such as this, that are beyond the response capacity of existing institutions, an adaptive approach to valuation is suggested, that provides stakeholders with opportunities for mutual learning, to reframe the problem in a broader context that includes cumulative impacts of further regional development that would be supported by the Hidrovia, to reconsider their values in light of new information, and to engage in a process of negotiation and conflict resolution regarding what is to be sustained. The results of this process can then provide a set of criteria for evaluating the success of development efforts, and to identify inevitable tradeoffs. Valuation becomes an institutional problem, of access to the decision-making process. The value of a participatory process, and the costs of not including stakeholders, are discussed with reference to case studies elsewhere.

A B S T R A C T The conservation of semen may have its costs reduced when used within a certain period of time through cooling techniques. These techniques are alternatives to reproductive management in fish farms, optimizing fertilization of oocytes and ensuring satisfactory reproduction. The quality of the extenders is essential, since it guarantees the maintenance of sperm cells. The tambaqui (Colossoma macropomum) is an endemic species from Brazil and reared in tropical regions throughout the world. Its supply chain is trending upward and production technologies are being improved, both by governmental programs and private initiative, as is the case of fish farms such as Delicious Fish in the state of Mato Grosso, Brazil, where this study was carried out. Different concentrations of cryoprotectants added in the extenders were tested during cooling of fresh semen of C. macropomum, and their motility was analyzed. Six males with secondary reproductive attributes of Neotropical migratory species were selected, weighed and hormonally induced. After stripping the semen through anteroposterior massage, a pool of semen from all the animals was constituted. The extenders tested were: T1: BTS (Beltsville Thawing Solution); T2: BTS + 1% Me2SO (dimethyl sulfoxide); T3: BTS + 2.5% Me2SO; T4: BTS + 5% Me2SO; T5: BTS + 8% Me2SO; T6: BTS + 1% Me2NCHO (dimethylformamide); T7: BTS + 2.5% Me2NCHO; T8: BTS + 5% Me2NCHO; T9: BTS + 8% Me2NCHO e T10: cooled pure semen. The progressive motility (PM%) of the samples was analyzed. After the analyses, the pool of semen was kept in eppendorfs, one for each analysis per day, and stored in refrigeration at 4 ± 1 °C. The seminal parameters were evaluated every 24 h to observe sperm viability. The statistic analyses were performed using the STATISTICA software. The motility of the semen “in natura” for each treatment was 95%, 88%, 78%, 85%, 67%, 72%, 60%, 57%, 47%, 83%, for the treatments T1, T2, T3, T4, T5, T6, T7, T8, T9 and T10, respectively. The progressive motility rate gradually decreased over time, varying according to the extenders. After four days the motility was 32% (T1), 33% (T2), 37% (T3), 27% (T4), 12% (T5), 38% (T6), 30% (T7), 22% (T8), 8% (T9) e 12% (T10). The increase in concentration of both internal cryoprotectants showed no significant difference for the treatments, except for T9, at 5% of significance (p < 0.05). The use of BTS without internal cryoprotectant did not reduce the efficiency of preservation of semen. However, the increase in the concentration of internal cryoprotectant has demonstrated a reduced percentage rate, particularly at concentrations of 8%. According to the extenders used, BTS + 1% of Me2NCHO presented the best sperm motility.