Emiko Kawakami de Resende

Fishes from the Parque Nacional do Pantanal Matogrossense, upper Paraguai River basin, Brazil

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.

Associação entre características de desempenho de tilápia-do-nilo ao longo do período de cultivo

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.

Growth curve by Gompertz nonlinear regression model in female and males in tambaqui (Colossoma macropomum)

Was evaluated the pattern of growth among females and males of tambaqui by Gompertz nonlinear regression model. Five traits of economic importance were measured on 145 animals during the three years, totaling 981 morphometric data analyzed. Different curves were adjusted between males and females for body weight, height and head length and only one curve was adjusted to the width and body length. The asymptotic weight (a) and relative growth rate to maturity (k) were different between sexes in animals with ± 5 kg; slaughter weight practiced by a specific niche market, very profitable. However, there was no difference between males and females up to ± 2 kg; slaughter weight established to supply the bigger consumer market. Females showed weight greater than males (± 280 g), which are more suitable for fish farming purposes defined for the niche market to larger animals. In general, males had lower maximum growth rate (8.66 g / day) than females (9.34 g / day), however, reached faster than females, 476 and 486 days growth rate, respectively. The height and length body are the traits that contributed most to the weight at 516 days (P <0.001).

Avaliação genética de características morfométricas em tilápias do Nilo cultivadas

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.

Sperm quality of the Amazon catfish Leiarius marmoratus (Gill, 1870) after cold storage

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 (P<0.05). The duration of motility increased (P<0.05), reaching its peak after three hours of storage. The motility quality score showed a quadratic pattern. No statistical differences were observed when sperm morphology was assessed (P>0.05), 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.

Isolation and characterization of polymorphic microsatellites in the threatened catfish Jaú, Zungaro jahu (Siluriformes, Pimelodidae)

This paper describes eight polymorphic microsatellite loci of the large migratory catfish Jaú, Zungaro jahu, a threatened species in the Paraguay—Paraná 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.

Genetic pattern and demographic history of Salminus brasiliensis: population expansion in the Pantanal Region during the Pleistocene

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.

O Departamento Peixe/Pesca

This paper concerns about the historic of the Fish/Fishery Department development at INPA — Instituto Nacional de Pesquisas da Amazonia. Now a day, this Department is formed by six divisions. The Division of Fishery do the evaluation of the fish stock ay using catch and landing data, field observations on catch methods, behaviour of fishing fleet, etc... The Division of Fish Biology takes place on systematic characterization of amazonian fish species, the study of food and feeding habits and reproduction according to the annual water level cycling, the differences on fish fauna related to the main types of water, as well as parasitology and icthyopathology. The Division of Aquatic Ecology analyses the limnological data of lakes and rivers of the amazonian region related to different types of water; special attention has been given to aquatic macrophites and its potential utilization in agriculture as fertilizer and cattle food. The Division of Fish Technology analyses the chemical composition of regional fishes, it develops preservation methods like as salting, drying and curing as well as quality control standards. The Division of Fish Culture develops culture methods of regional fishes, the study of natural and artificial ways of reproduction and experiments with different food formulations. The Division of Aquatic Mammals studies the biology, ecology and physiology of peixe-boi (manatee) and two species of river dolphins.