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Copyright of Neotropical Ichthyology is the property of Neotropical Ichthyology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Studies that assess reproduction dynamics and ichthyoplankton distributions are scarce for the upper Uruguay River, especially in environments such as tributary mouths. Therefore, this study aimed to evaluate: (i) ichthyoplankton composition; (ii) spatial and temporal variation in ichthyoplankton abundance; and (iii) relationships between environmental variables and the abundance of ichthyoplankton during one annual cycle in this region. Monthly samples were collected from September 2001 to August 2002 in 48 h cycles at 6 h intervals between each sampling. Samples of eggs and larvae were collected from three of the main tributaries of the region (Ligeiro, Palomas and Chapecó rivers) and from three stretches of the Uruguay River near the confluence of these tributaries. Surface samples were collected with a 0.5 mm mesh cylindro-conical net. In general, reproductive seasonality was well-defined between October and February. It was most intense from November to January, when the photoperiod reached its highest values, flow was decreased, and the water temperature was increased. Based on egg and larval distributions, we found that spawning occurred mainly in the Ligeiro and Chapecó tributaries and in the Uruguay/Chapecó section. In contrast, fish spawning in the sites downstream of dams was more restricted. Finally, a difference was observed between the egg and larval distributions of the main river and its tributaries: the greatest reproductive activity in the tributaries occurred during periods of high flow and increased water temperature, while in the main river, more eggs and larvae were observed when the flow decreased and the water temperature increased. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the distribution and abundance of fish eggs and larvae in three important tributaries (Chapecó, Peixe, and Ligeiro rivers) of the Upper Uruguay River. The spatial and temporal distribution of fish eggs and larvae were studied as well as the correlation between environmental parameters and the abundance of ichthyoplankton species. The study was conducted between October 2005 and September 2006. Ichthyoplankton samples were collected at night with cylindroconical 0.5-mm mesh plankton nets every 5 days. Of the 591 samples collected, 170 contained ichthyoplankton organisms, resulting in the capture of 12,847 fish eggs and 962 fish larvae. Twenty-seven fish species were observed, of which 69% were Characiforms and 27% were Siluriforms. Among the fish species captured, the representatives were predominantly young forms of small and medium size fishes, with rheophilic species occurring infrequently. Eggs occurred exclusively between October and January, while the highest larvae occurrence was observed between November and December. Fish larvae assemblage structure was shown to be related to some environmental variables. There was a tendency of higher values of water temperature and velocity at the lower sampling sites than at the upper ones, as well an increase number of eggs and larvae. The study tributaries serve as reproduction sites and nursery areas for several fish species of the Upper Uruguay River; thus, the maintenance of their integrity is important for the preservation of diversity and enhancement of fisheries in the region. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência & Saúde Coletiva is the property of Associacao Brasileira de Pos-Graduacao em Saude Coletiva and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Interface - Comunicação, Saúde, Educação is the property of Fundacao UNI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Jundiá, Rhamdia quelen, is considered to be a fish with great farming potential in South and Southeast Brazil. For this species, early male sexual maturation has a negative influence on the growth rate. Thus, the possibility of using sterile jundiá triploids becomes an interesting option in fish farming. This study assessed the effect of pressure shock on the production of Jundiá triploid larvae and their yield at the end of yolk absorption. Exposure for 5 minutes at 3.4473950 x 107 Pa after 2 or 5 minutes post-fertilization was enough to induce 100% triploidy in R. quelen, showing 29.1% and 20.5%, respectively, of larval yield at the end of the endogenous feeding period. [ABSTRACT FROM PUBLISHER]

Simple, effective protocols for cryopreserving milt of five Brazilian migratory characids (Brycon orbignyanus , Prochilodus lineatus , Piaractus mesopotamicus , Salminus maxillosus and Leporinus elongatus ) and one Brazilian migratory catfish (Pseudoplatystoma corruscans ) are described. Milt was frozen and stored in dry shippers immediately after collection, making the procedure practical for use in the field. A diluent of 5% glucose, 10% dimethyl sulphoxide and 10% egg yolk was effective for all of the characid species, and a diluent of 10% methanol and 15% powdered milk was effective for P. corruscans . Milt was thawed in an ambient temperature water bath (28–30° C). Activation of thawed milt was effective with either saline (0·9 or 0·45% NaCl) or bicarbonate (1% NaHCO[sub 3] ). Fertilization rates with frozen milt varied between 49 and 300% of the control. Application of the technology for increasing genetic diversity in hatchery programmes for enhancement, mitigation or conservation breeding is discussed, as is its application in aquaculture. Inappropriate use of the technology can threaten wild biodiversity and appropriate legislation and education may be required for its responsible use. [ABSTRACT FROM AUTHOR]

Length–weight relationships were estimated for 56 species, representing seven orders and 17 families of fishes from the Upper Uruguay River, Brazil. For most of these species, no length–weight relationships were previously available. [ABSTRACT FROM AUTHOR]

This study aimed to describe the production process of an educational booklet focusing on health promotion of pregnant women. The action research method was used in this process composed of the following steps: choice of the content based on the needs of pregnant women, creation of illustrations, content preparation based on scientific literature, validation of the material by experts and pregnant women. This work resulted in the final version of the booklet, which was entitled "Celebrating life: our commitment with the health promotion of pregnant women". Active participation of health professionals and pregnant women through dialogue and collective strategy permeated the process of development of the booklet. The opinions of pregnant women and experts who considered the booklet enriching and enlightening justify the use of it as an additional resource of educational activities carried out during the prenatal care. [ABSTRACT FROM AUTHOR]

• A Polynomial State-Space model for fish population dynamics in areas affected by the golden mussel. • Model identification validation for ten different species. • Discussion of real-life applicable control strategies with a Nonlinear Model Predictive Control framework. • Numerical simulations. The invasion of exotic species in aquatic environments is one of the several disturbance factors responsible for altering the dynamics of fish communities. The golden mussel Limnoperna fortunei was first recorded in the upper Uruguay river, Brazil, in 2012 and, since then, it has been needed to discuss and evaluate how this invasive species interferes with the dynamics of the ten most abundant fishes of this region. Literature lacks works that investigate how to model and control the effect of such kind of invasion. This paper proposes a polynomial-nonlinear state-space representation to model the dynamics of the these fish communities, whose parameters are identified with the use of Least Squares procedures, considering in loci collected data from 2007 to 2016. This work also evaluates quantitatively, by relying on simulation results, how the (sudden) presence of the golden mussel medelled with the aquatic life of the upper Uruguay river. The obtained model allows some ambitious automatic control objectives. Using a Nonlinear Model Predictive Control (NMPC) approach, an automatic controller is designed to determine how much and how often the golden mussel should be removed from the water in order for the most affected species to once again exhibit sustainable life conditions, in terms of its K Condition Factor and abundance. The NMPC strategy is synthesized considering performance constraints and piecewise-constant control trajectories. By relying on simulation results, this work elucidates how an automatic controller could be implemented as management policies established by environmental agencies to gradually restore the fish ecological balance of the upper Uruguay river, previously unsettled by an exotic invasor. [ABSTRACT FROM AUTHOR]