bluuebunny/crossref_metadata_2025 huggingface dataset:
A Elaboração do Plano de Desenvolvimento Urbano Integrado da região metropolitana da Baixada Santista : avanços e desafios : o processo de contratação, elaboração e implementação dos PDUIs, contemplando as soluções de governança do plano, a definição dos instrumentos, os arranjos de gestão e a solução de conflitos de uso e ocupação do solo : componente B : relatório de pesquisa
Authors:   Instituto de Pesquisa Econômica Aplicada (Ipea)
Published: June 2021

Apresenta-se um painel acerca da governança da RM da Baixada Santista, no âmbito da quinta etapa do projeto Governança Metropolitana no Brasil, com foco em seu componente B (processo de contratação, elaboração e implementação do Plano de Desenvolvimento Urbano Integrado da RM da Baixada Santista). Com essa finalidade, na seção 2, será discutido o processo de implementação dos instrumentos de política urbana no contexto da cooperação interfederativa, com vistas a dar continuidade ao acompanhamento do processo local de elaboração e implementação do PDUI-BS. Na seção 3, será apresentado o contexto da compatibilização entre esse plano e os planos diretores dos municípios integrantes da região. Na seção 4, será revelado o mapeamento de conflitos de uso do solo, identificando-os e classificando-os por tipologias, além de apontar desafios e soluções a partir de estudos de caso. Na sequência, serão realizadas as considerações finais. As análises e a realização deste relatório foram fruto da parceria de dois grupos de pesquisa da Universidade Católica de Santos(UniSantos), de forma integrada e interdisciplinar: Direito Ambiental de Cidades, do Programa de Pós-Graduação Stricto Sensu em Direito Ambiental e Internacional, e o Observatório Socioespacial da Baixada Santista, do curso de graduação e do Programa de Mestrado em Arquitetura e Urbanismo.
Identificação e caracterização das relações interfederativas na região metropolitana de Goiânia : soluções de financiamento para o desenvolvimento urbano-metropolitano : componente C : relatório de pesquisa
Authors:   Instituto de Pesquisa Econômica Aplicada (Ipea)
Published: June 2021

Para efeito didático operacional, este relatório priorizou analisar as soluções de financiamento para o desenvolvimento metropolitano da RM de Goiânia, direcionadas para estas quatro funções públicas de interesse comum (FPICs) específicas (as tabelas de dados e o mapeamento apresentados nas páginas seguintes seguem este critério). Antes de adentrar, propriamente, a questão dos fundos de financiamento existentes, faz-se pertinente uma breve apresentação do perfil socioeconômico e a composição territorial da região.
COMPARISON OF PREDICTED FAILURE AREA AROUND THE BOREHOLES IN THE STRIKE-SLIP FAULTING STRESS REGIME WITH HOEK-BROWN AND FAIRHURST GENERALIZED CRITERIA
Authors: Lakirouhani Ali , Bahrehdar Mohammad , Medzvieckas Jurgis , Kliukas Romualdas
Published: June 2021

Breakout is a shear failure due to compression that forms around the borehole due to stress concentration. In this paper, the breakout theory model is investigated by combining the equilibrium elasticity equations of stress around the borehole with two Hoek-Brown and Fairhurst generalized fracture criteria, both of which are based on the Griffith criterion. This theory model provides an explicit equation for the breakout failure width, but the depth of failure is obtained by solving a quartic equation. According to the results and in general, in situ stresses and rock strength characteristics are effective in developing the breakout failure area, As the ratio of in-situ stresses increases, the breakout area becomes deeper and wider. Because in the shear zone, the failure envelope of the Fairhurst criterion is lower than the Hoek-Brown failure criterion, the Fairhurst criterion provides more depth for breakout than the Hoek-Brown criterion. However, due to the same compressive strength of the rock in these two criteria, the same failure width for breakout is obtained from these two criteria. Also, the results obtained for the depth of failure from the theoretical model based on the Fairhurst criterion are in good agreement with the laboratory results on Westerly granite.
The G 305 Star-forming Region. II. Irregular Variable Stars
Authors: Medina N. , Borissova J. , Kurtev R. , Alonso-García J. , Román-Zúñiga Carlos G. , Bayo A. , Kounkel Marina , Roman-Lopes Alexandre , Lucas P. W. , Covey K. R. , Fórster Francisco , Minniti Dante , Adame Lucia , Hernández Jesús
Published: June 2021

We present a catalog of 167 newly discovered, irregular variables spanning a ∼7 deg2 area that encompasses the G 305 star-forming complex, one of the most luminous giant H ii regions in the Galaxy. We aim to unveil and characterize the young stellar object (YSO) population of the region by analyzing the K
s-band variability and JHK
s infrared colors from the VISTA Variables in the Vía Láctea survey. Additionally, SDSS-IV APOGEE-2 infrared spectra of selected objects are analyzed. The sample shows relatively high amplitudes (0.661 mag < ΔK

S
< 3.521 mag). Most of them resemble sources with outbursts with amplitude >1 mag and duration longer than a few days, typically at least a year, known as eruptive variables. About 60% are likely to be Class II/flat/I objects. This is also confirmed by the spectral index α when available. From the analysis of APOGEE-2 near-infrared spectra of sources in the region, another 122 stars are classified as YSOs and display some infrared variability. The measured effective temperature T
eff peak is around 4000 K, and they are slightly supersolar in metal abundance. The modal radial velocity is approximately −41 km s−1. Combining available catalogs of YSOs in the region with our data, we investigate the spatial distributions of 700 YSOs. They are clearly concentrated within the central cavity formed by the massive clusters Danks 1 and 2. The calculated surface density for the entire catalog is 0.025 YSOs pc−2, while the central cavity contains 10 times more objects per area (0.238 YSOs pc−2).
Discovery of Carbon Monoxide in Distant Comet C/2017 K2 (PANSTARRS)
Authors: Yang 杨 Bin 彬 , Jewitt David , Zhao Yuhui , Jiang Xuejian , Ye Quanzhi , Chen Ying-Tung
Published: June 2021

Optical observations of the Oort cloud comet C/2017 K2 (PANSTARRS) show that its activity began at large heliocentric distances (up to 35 au), which cannot be explained by either the sublimation or the crystallization of water ice. Supervolatile sublimation, most likely of carbon monoxide (CO), has been proposed as a plausible driver of the observed mass loss. Here, we present the detection of the J = 2−1 rotational transition in outgassed CO from C/2017 K2 when at heliocentric distance r

H
= 6.72 au, using the James Clerk Maxwell Telescope. The CO line is blueshifted by 0.20 ± 0.03 km s−1 with an area and width of 8.3 ± 2.3 mK km s−1 and 0.28 ± 0.08 km s−1, respectively. The CO production rate is Q
CO = (1.6 ± 0.5) × 1027 s−1. These are the first observations of a gaseous species in C/2017 K2 and provide observational confirmation of the role of supervolatile sublimation in this comet.
Year 1 of the Legacy Survey of Space and Time (LSST): Recommendations for Template Production to Enable Solar System Small Body Transient and Time Domain Science
Authors: Schwamb Megan E. , Jurić Mario , Bolin Bryce T. , Dones Luke , Greenstreet Sarah , Hsieh Henry H. , Inno Laura , Jones R. Lynne , Kelley Michael S. P. , Knight Matthew M. , Reach William T. , Seccull Tom , Snodgrass Colin , Trilling David E. ,   for the Vera C. Rubin Observatory LSST Solar System Science Collaboration
Published: June 2021

The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) will discover ∼6 million solar system planetesimals, providing in total over a billion photometric and astrometric measurements in 6 broad-band filters. Rubin Observatory's automated data reduction pipelines will employ difference imaging; templates representing the static sky will be subtracted from the nightly LSST observations in order to identify transient sources, including solar system moving objects. These templates are expected to be generated by coadding high quality images of the same pointing from the previous year's survey observations. The first year of LSST operations will require a different method for generating templates, if solar system discoveries are to be reported daily like Year 2 and beyond. We make recommendations for template production in the LSST's first year and present the opportunities for solar system small body transient and time domain science enhanced by this change.
The Dynamics of the Transition from Kardashev Type II to Type III Galaxies Favor Technosignature Searches in the Central Regions of Galaxies
Authors: Wright Jason T. , Carroll-Nellenback Jonathan , Frank Adam , Scharf Caleb
Published: June 2021

We present a video of a simulation showing the expansion front of a technological species settling a Milky Way-like galaxy, created using the model described in Carroll-Nellenback et al. It illustrates how even very conservative rates of settlement ship launches and ship ranges can quickly lead to a galaxy endemic with technology, and how the rotational and peculiar motions of stars contributes to the expansion. This video confirms and validates previous work showing that the centers of galaxies are promising search directions for SETI.
The Distribution of Ground-based Reflecting Telescopes with Respect to Altitude
Authors: Smith Graeme H.
Published: June 2021

The altitude distribution of ground-based reflecting telescopes with primary mirrors of diameter 1.0 m or more is presented graphically and compared with hypsographic data for the Earth’s land surface. It is verified that large optical reflectors are more weighted to higher elevations than the land surface. Approximately 60% of the combined collecting area of the telescopes is situated between elevations of 2000 and 3500 m.
Seaweeds in ornamental aquaria in Brazil: anticipating introductions
Authors: Torrano-Silva Beatriz N. , Amancio Carlos E. , Oliveira Eurico C.
Published: June 2021

Home and public sea aquaria are becoming more and more popular worldwide. Aquaria species are selected for their aesthetic appeal in terms of color, shape or behavior. In Brazil, most species are imported from remote places, usually tropical areas around the world. Water discarded from aquaria often includes organisms, or their propagula, that may become locally established. There have been extensive discussions concerning the vectors of species dispersion from their native areas, which includes ornamental aquaria. In order to evaluate the potential of local aquaria as a source of non native macro algae, we surveyed sea-aquaria shops and exhibition aquaria in São Paulo State. Thirty eight species of seaweeds were isolated in the aquaria surveyed. Among them, six have not been recorded from Brazil and nineteen were not reported for São Paulo littoral, including Caulerpa scalpelliformis var. denticulata the only species that so far deserves being designated as invasive in Brazil. The present paper should alert environmental agencies and aquaria shops about the risk of involuntarily introducing non-native species through aquariophyly.
Rapid assessment survey for exotic benthic species in the São Sebastião Channel, Brazil
Authors: Marques Antonio C. , Dos Santos Klôh Aline , Esteves Migotto Alvaro , Cabral Ana C. , Ravedutti Rigo Ana P. , Lima Bettim Ariane , Razzolini Emanuel L. , Matthews Cascon Helena , Bardi Juliana , Pioli Kremer Laura , Manzoni Vieira Leandro , Arruda Bezerra Luis E. , Haddad Maria A. , Ruy de Oliveira Filho Ronaldo , Millan Gutierre Silvia M. , Pires Miranda Thaís , Franklin Jr. Wilson , Moreira da Rocha Rosana
Published: June 2021

The study of biological invasions can be roughly divided into three parts: detection, monitoring, mitigation. Here, our objectives were to describe the marine fauna of the area of the port of São Sebastião (on the northern coast of the state of São Paulo, in the São Sebastião Channel, SSC) to detect introduced species. Descriptions of the faunal community of the SSC with respect to native and allochthonous (invasive or potentially so) diversity are lacking for all invertebrate groups. Sampling was carried out by specialists within each taxonomic group, in December 2009, following the protocol of the Rapid Assessment Survey (RAS) in three areas with artificial structures as substrates. A total of 142 species were identified (61 native, 15 introduced, 62 cryptogenic, 4 not classified), of which 17 were Polychaeta (12, 1, 1, 3), 24 Ascidiacea (3, 6, 15, 0), 36 Bryozoa (17, 0, 18, 1), 27 Cnidaria (2, 1, 24, 0), 20 Crustacea (11, 4, 5, 0), 2 Entoprocta (native), 16 Mollusca (13, 3, 0, 0). Twelve species are new occurrences for the SSC. Among the introduced taxa, two are new for coastal Brazil. Estimates of introduced taxa are conservative as the results of molecular studies suggest that some species previously considered cryptogenic are indeed introduced. We emphasize that the large number of cryptogenic species illustrates the need for a long-term monitoring program, especially in areas most susceptible to bioinvasion. We conclude that rapid assessment studies, even in relatively wellknown regions, can be very useful for the detection of introduced species and we recommend that they be carried out on a larger scale in all ports with heavy ship traffic.
Effects of the secondary metabolites from Canistrocarpus cervicornis (Dictyotales, Phaeophyceae) on fertilization and early development of the sea urchin Lytechinus variegatus
Authors: Ortiz-Ramírez Fredy A. , Vallim Magui Aparecida , Negrão Cavalcanti Diana , Laneuville Teixeira Valéria
Published: June 2021

Marine organisms are rich sources of natural products that, among other activities, help to maintain the species equilibrium. Samples of the marine brown alga Canistrocarpus cervicornis (Kützing) De Paula & De Clerck were collected in Búzios, Rio de Janeiro, Brazil, in June 2006. The extract was obtained in CH2Cl2 and subjected to fractionation by chromatographic methods in order to isolate and purify the compound (4R, 7R, 14S)-4α, 7α-diacethoxy-14-hydroxydolastane-1(15), 8-dien. Then, the effects of the extract and the dolastane diterpene on zygotes and gametes of the sea urchin Lytechinus variegatus were evaluated. The exposure of male and female gametes to the C. cervicornis extract promoted, respectively, a reduction of 10-30% in fertilization and a 20 to 70% decrease in the number of eggs. Furthermore, the exposure of zygotes to the extract inhibited their development up to 86.7 ± 1.6% (at a concentration of 250 µg mL-1), as well as generating abnormalities in 39-50% of zygotes. The results of the dolastane diterpene showed no evidence of inhibition in the zygotes’ development, thought it was proved to induce anomalies. At higher concentrations (25 and 50 µg mL-1), it was possible to observe cell lyses.
Otolith shape analysis as a tool for stock identification of the southern blue whiting, Micromesistius australis
Authors: Leguá Javier , Plaza Guido , Pérez Darío , Arkhipkin Alexander
Published: June 2021

The southern blue whiting, Micromesistius australis (Norman, 1937), is an important demersal resource associated with the slope and continental shelf of southern Chile, Argentina and the Malvinas/Falkland Islands. Recent studies have reported schools of adult fish from Atlantic waters migrating along the southern Chilean coast in mid-winter, moving northwards to spawn in August (47º-51ºS), and then returning to Atlantic waters, presumably to feed. The migratory pattern suggests the presence of one or more stock units associated with the South American coast. In the present study, “otolith morphometry” is used to determine the stock structure of M. australis based on applications of basic size descriptors (SDs) (area, perimeter and otolith size), shape indices (SIs) (circularity, squareness, shape factor, roundness, ellipticity), and normalised elliptical Fourier descriptors (NEFDs). Samples were collected during the winter and spring of 2010, during the reproductive period, in the economic zone of southern Chile (36º-57ºS), in the Pacific Ocean and around the Falkland Islands economic zone (50º-52ºS) in the Atlantic Ocean. Analyses were conducted to include the effects of size, sex and age. A stepwise canonical discriminant analysis showed that fish were successfully discriminated with SDs, SIs and NEFDs. In this analysis, 86.4% and 70.1% of the fish were correctly classified as belonging to the Atlantic and Pacific stocks, respectively. A multivariate analysis of variance showed that the mean values of the NEFDs, SDs, and SIs did not vary significantly between sexes within areas (P > 0.05), but varied significantly between the Pacific and Atlantic oceans (P < 0.05). These results highlighted that otolith shape analysis can be a useful tool to evaluate the potential level of mixing in feeding areas where both stocks, the Pacific and Atlantic units, are expected to co-occur.
Historical analysis of somatic growth of Chilean hake (Merluccius gayi gayi) off central coast of Chile
Authors: Cerna Francisco , Cubillos Luis A. , Plaza Guido
Published: June 2021

Somatic growth was studied in the Chilean hake stock off central coast of Chile, through the application of Von Bertalanffy equation (vB) as a non-linear mixed effect model (NLME) on length-at-agedata derived from otolith readings made at Instituto de Fomento Pesquero since 1972. Average growth rates for each year from 1972 to 2009 were estimated. Growth parameters of vB curves were analyzed for three major periods regarding changes in stock biomass (1972-1990, 1991-2003 and 2004-2009). Results indicated that the average growth rate showed inter-annual variations that did not exceed ±15 cm of total length around the historical average of males and females, showing no persistent tendency towards sustained increase or decrease in somatic growth rate. Growth curves obtained with the vB parameters, estimated for the three periods, showed a similar trajectories until age 7 and 8 years, in both male and females. Changes after this age may be a result of a decrease of larger fish removed by the selective effect of fishing, which triggered variations in the fitted curves, but not necessarily changes in somatic growth of these ages in the population. The results demonstrated that the individual growth of hake has not changed significantly since 1972, without observing a density-dependent effect with decreasing abundance.
A preliminary evaluation of the San Pedro daisy (Lasianthaea podocephala) tuber powder, as a feed additive on the intensive culture of shrimp (Litopenaeus vannamei) under laboratory conditions
Authors: Martínez-Porchas Marcel , Noreña-Rivera Enrique Israel , Martínez-Córdova Luis Rafael , Lopez-Elias José Antonio , Mendoza-Cano Fernando , Bringas-Alvarado Lorena , Lugo-Sánchez María Elena
Published: June 2021

An experimental study was carried out during seven weeks to preliminarily evaluate the effect of the dietary inclusion of powder from the tuber Lasianthaea podocephala, commonly known as the San Pedro daisy or pionilla, as a feed additive on the production parameters, food consumption, and nutritional condition of the white shrimp, Litopenaeus vannamei, intensively farmed under laboratory conditions. Hypothetically, the additive should improve these parameters as it does when used for humans. The powder was included at different levels (0 [Control], 0.2 [T1] and 1 g kg-1 [T2]) in a commercial shrimp feed. The tuber powder exhibited a free amino acid profile being arginine (8.59 mg g-1) and glutamine (3.36 mg g-1) the most abundant. Feed consumption was not influenced by any treatment; however, the survival and the overall production responses were higher in both treatments using the powder (T1 and T2) compared to the control. No significant differences were detected in muscle concentrations of lactate and glucose, although higher protein and lower cholesterol concentrations were observed in shrimp reared in the control. The lower cholesterol concentration of shrimp from the control could be associated to a poor nutritional status. In conclusion, addition of the powder of San Pedro daisy did not improve the feed consumption, but apparently had a positive effect on survival, production response and nutritional status of shrimp. These responses could be associated to an hypothetic effect of some plant components at a nutritional-molecular level, or to a possible antimicrobial effect; however, further specific studies are needed.
Comparative histological description of the digestive and visual system development of larval chame Dormitator latifrons (Pisces: Eleotridae)
Authors: López-López Vanesa V. , Rodríguez M. de O. Gustavo A. , Galavíz Mario A. , Román Reyes Cristóbal , Dabrowski Konrad , Haws María C. , Medina-Hernández Eva A.
Published: June 2021

This study was focused on the morphological description of chame larvae from one to six days post-hatching (dph), in order to generate information that helps understanding their feeding ability in early stages. The larvae were obtained by hormonal induction of a broodstock, using implants of GnRH synthetic analogues, during the spawning season from September to November 2010. The samples were included in historesin, and stained with hematoxylin-eosin. It was described that, once the larva hatched has a large amount of yolk it is gradually absorbed (from 1 to 3 dph). At day four, there is an open oral cavity with dental structures, the eye development is complete and there was pigmentation on it, the gills are observable and the foregut was differentiated in anterior and posterior intestine, showing the presence of digestive vacuoles in the anterior intestine. By five dph the larvae has developed muscle fibers and a structure identified as the stomach. At sixth dph, it is possible to identify the pancreas, the intestinal folds, and the brush border membrane, and there were food particles and bacteria rests in the gut. Based on the above, it is concluded that the larvae of D. latifrons from the fourth dph fully developed organs and systems that help the search of food, so they are capable of starting with exogenous feeding.
Total mercury in female Pacific sharpnose sharks Rhizoprionodon longurio and their embryos
Authors: Frías-Espericueta Martín G. , Zamora-Sarabia Francia K.G. , Márquez-Farías J. Fernando , Osuna-López J. Isidro , Ruelas-Inzunza Jorge , Voltolina Domenico
Published: June 2021

We determined the Hg content of blood, placenta and umbilical cord of 20 pregnant females of the viviparous Pacific sharpnose shark, Rhizoprionodon longurio and of the livers of the embryos contained in their right and left uterus, aiming to provide information on the amount of this metal offloaded during pregnancy by the mother to the embryos. Hg content varied by close or higher than one order of magnitude in all tissues and showed the decreasing trend: maternal blood > umbilical cord > placenta > embryonic livers, with placenta and embryonic livers significantly lower than maternal blood. There were highly significant correlations (P < 0.001) between the Hg content of maternal blood, cord, and placenta. Those between embryonic livers and maternal blood, cord and placenta were not significant (P > 0.05). The results suggest transplacental Hg transfer and that the liver is not the main site of Hg accumulation.
Population structure of the burrowing crab Neohelice granulata (Brachyura, Varunidae) in a SW Atlantic salt marsh
Authors: Angeletti Sabrina , Cervellini Patricia Marta
Published: June 2021

Neohelice granulata inhabits estuarine and protected coastal areas in temperate regions, and is the most dominant decapod crustacean in the Bahía Blanca estuary. The population structure was studied during a year in a SW Atlantic salt marsh located in the Bahía Blanca estuary, Argentina. Crabs were sampled monthly from August 2010 to July 2011. The maximum observed density was 39 crabs/m2 in February and 70 burrows/m2 in May. The maximum carapace width (CW) in males was 32 mm and 27.5 mm in females. Medium size crabs were between 16 and 20 mm CW. Significantly smaller sized crabs were observed at the lower intertidal regions (p
The biology and ecology of the jumbo squid Dosidicus gigas (Cephalopoda) in Chilean waters: a review
Authors: Ibáñez Christian M. , Sepúlveda Roger D. , Ulloa Patricio , Keyl Friedemann , Pardo-Gandarillas M. Cecilia
Published: June 2021

The jumbo squid Dosidicus gigas is the most abundant cephalopod species in the southeastern Pacific Ocean, which supports the biggest cephalopod fishery in the world. Due to its growing economic importance, the population growth and distributional expansion of this squid is being increasingly studied. Nevertheless, some basic features of the biology of D. gigas are still unknown or have been poorly investigated. In this review we summarize the known information regarding the biology and ecology of this species in the southeastern Pacific Ocean; we focus on the Chilean region in order to propose hypotheses and research lines for a better understanding the life history of this organism. Available data on the size structure, reproduction and genetics of D. gigas allows us to propose hypotheses related to the squid’s life history traits. Based on the current literature and publications of colleagues, we propose two hypotheses regarding the effect of spatial variation on the life history of D. gigas. Hypothesis 1: Squids mature at large sizes and spawn in oceanic waters with warm temperatures where paralarvae and juveniles develop. Immature squids migrate near shore to feed, grow and mature, and then return to the offshore sites to spawn. Hypothesis 2: Alternatively, juvenile D. gigas in the oceanic zone do not migrate to coastal waters and mature at small sizes compared to individuals living near the coast that mature at larger size and migrate to oceanic waters to spawn. We provide background information about the feeding behavior and parasitism of this species, suggesting that D. gigas is an important trophic link in the southeastern Pacific marine ecosystem. However, more studies on the feeding habits, reproduction and parasite load are needed not only to test hypotheses proposed in this study, but also to advance the overall knowledge of this species.
Use of probiotics Bacillus cereus var. toyoi and Bacillus subtilis C-3102 in the diet of juvenile Nile tilapia cultured in cages
Authors: Garcia-Marengoni Nilton , Cézar de Moura Milton , De Oliveira Newton Tavares Escocard , Bombardelli Robie Allan , Menezes-Albuquerque Daniele
Published: June 2021

This study aimed at evaluating the gut colonization by probiotics, the influence on the bacterial microflora, hematological profile, fish performance, rates body and proximate composition and water quality parameters in the cultivation of Nile tilapia juvenile of the Genetically Improved Farmed Tilapia (GIFT) strain. 1800 fry were randomly distributed into four experimental groups (T1 = basal diet (BD) without probiotic addition, T2 = BD + 0.5 % Bacillus cereus var. toyoi (BC), T3 = BD + 0.5% Bacillus subtilis C-3102 (BS); T4 = BD + 0.25 % BC + 0.25 % BS) with five replicates. Cages (0.175 m3) containing 90 tilapia fry (0.34 ± 0.06 g), were used as culture units and individually installed in 8.4 m3 ponds. Except for hemoglobin, hematocrit, glucose, and neutrophil levels, no differences in hematological profile were observed among the groups after 127 days of culture (P > 0.05). The probiotic bacteria either added individually or in combination, successfully colonized the intestines of the fish, without negatively influencing the intestinal bacterial microflora, growth rate, proximate composition, or water quality parameters (P > 0.05). Thus, dietary probiotic supplementation of juvenile Nile tilapia alters the hematological profile, especially hemoglobin, hematocrit, glucose, and neutrophil levels.
Channel catfish (Ictalurus punctatus Rafinesque, 1818): current status and problematic situation in Mexico
Authors: Lara-Rivera Ana Laura , Parra-Bracamonte Gaspar Manuel , Sifuentes-Rincón Ana María , Gojón-Báez Héctor Hugo , Rodríguez-González Hervey , Montelongo-Alfaro Isidro Otoniel
Published: June 2021

Channel catfish (Ictalurus punctatus) is one of the endemic fishes of North America with the greatest potential for aquaculture. Despite this, data of its current distribution is scare and many aspects of its dynamic and productive performance remain unknown. In the present study, results are reported from a literature search and field analysis for describing the current status of channel catfish in Mexico regarding its historical and current geographical distribution as well as the problems faced by fish farmers and production systems. We were able to identify a lack of information and indicators to properly assess the extent of the species natural habitat and its productive potential. The quality and availability of water are among the main problems of the industry. Food costs represent the larger cost-loss for producers and there is great heterogeneity on the management of both breeding and production farms. Much of the production dynamics follows a pattern of trial and error. It became clear the need to optimize and standardize the processes on the channel catfish production system and to properly characterize domestic and wild populations to maximize their potential.
Using shrimp head meal as protein replacement of fish meal in diets for juvenile of Totoaba macdonaldi (Gilbert, 1890)
Authors: Espinosa-Chaurand Luis Daniel , Silva-Loera Antonio , García-Esquivel Zaúl , López-Acuña Lus Mercedes
Published: June 2021

In diets for Totoaba macdonaldi juveniles (26.3 ± 4.7g y 13.6 ± 1cm) the partial replacement of fishmeal protein (HP) with shrimp head meal (HCC) was evaluated, over their growth, survival, fed conversion (FCA) and chemical composition of tissues and the apparent digestibility coefficient of dry matter (CDA), protein (CDAP) and lipids (CDAL) of these diets. The HCC used were from the whole shrimp head sun dried (F) and smashed shrimp head dehydrated in a hot air drier. Diets were isoproteic (55.5% crude protein), isolipídic (15% lipids) and isocaloric (4.6 kcal g-1) replacing 0% (control diet; DC), 15% (F15 and M15) and 30% (F30 and M30) of the HP protein by the HCC. At 57th day, survival with HCC (99.44 ± 1.92%) was higher than DC (88.89 ± 3.85 %). The gain weight, weight specific growth (TCE) and total intake were not statistically different (P > 0.05) between organisms feed with HCC, however with the M30 diet the TCE had higher average (0.99 ± 0.06) and growth (19.82 ± 1.64 g/fish). With diet M30 the FCA was the best significantly (1.61 ± 0.13) and the higher CDA (66.18 ± 1.28), CDAP (86.51 ± 0.53) and CDAL (72.29 ± 1.10). It concluded that replaced protein of HP by HCC in diet for juvenile totoaba improved the growth and CDAs, yielding better results with the inclusion of macerated HCC with a replacement level of 30%.
Identification of fish stocks of river crocker (Plagioscion ternetzi) in Paraná and Paraguay rivers by using otolith morphometric analysis
Authors: Avigliano Esteban , Comte Guy , Rosso Juan José , Mabragaña Ezequiel , Della Rosa Paola , Sanchez Sebastian , Volpedo Alejandra , Del Rosso Franco , Schenone Nahuel Federico
Published: June 2021

The identification of fish stocks in basic requirement for fishing management. The objective of this research was to describe for the first time otoliths river crocker (Plagioscion ternetzi) and to evaluate the existence of different fish stocks in the Paraguay River lower basin and the middle Paraná River (northeast Argentinean region and southeast Paraguayan region). For this purpose, five morphometric indexes applied on sagitta otolith (rectangularity, circularity AO/SO, SS/SO and PS/PO) were compared between the study sites. The sagittae otoliths are semicircular and with smooth edges. Sulcus acusticusis is heterosulcoid and curved, with an ostium open widely in the anterior margin of the otolith. Significant differences were observed for circularity, rectangularity, SS/SO and PS/PO (t-test, P < 0.05). The T2 Hotteling multiparametric analysis showed significant differences between the study sites (P < 0.006), while the canonical discriminant showed a high classification percentage of the individuals (>69%). The results indicates that the stocks populations would be partially separated, with a considerable flow of individuals between these rivers.
Wild populations of the invasive Australian red claw crayfish Cherax quadricarinatus (Crustacea, Decapoda) near the northern coast of Jalisco, Mexico: a new fishing and profitable resource
Authors: Vega-Villasante Fernando , Ávalos-Aguilar José J. , Nolasco-Soria Héctor , Vargas-Ceballos Manuel A. , Bortolini-Rosales José L. , Chong-Carrillo Olimpia , Ruiz-Núñez Martín F. , Morales-Hernández Julio C.
Published: June 2021

The red claw crayfish Cherax quadricarinatus is native to freshwater habitats of northern Australia and Papua New Guinea. Its high reproductive and adaptive capacity in different environments allows it to be cultivated, where escaped individuals have established wild populations in countries far from their natural range. In the late 90’s and beginning of the 21st century, this crayfish was introduced illegally along the coast of southern Jalisco. Mismanagement led to escape and dispersion. Currently there are wild crayfish in the Cajón de Peñas Reservoir and surrounding streams in northern Jalisco, Mexico. The aim of this study was to evaluate the presence of C. quadricarinatus in fisheries in this area of Jalisco and analyze its importance in generating economic benefits for fishermen, comparing these results with those of the fishery for M. americanum, whose fishery is traditional. To catch specimens, traps were set for 24 h in the La Sanja Stream and the Cajón de Peñas Reservoir. The results of the survey showed that C. quadrica rinatus is an important part of the crustacean catch in this area: 32% of the total catch in the stream corresponded to C. quadricarinatus and the rest to M. americanum. While 85% of the catch in the dam corresponded to C. quadricarinatus, only 15% referred to M. americanum. Crayfish fishing in the reservoir is now an important part of the productive activity of local families dependent on fishing. The ecological consequences of wild crayfish proliferation remain to be studied.
Anticipation of Artemia sp. supply in the larviculture of the barber goby Elacatinus figaro (Gobiidae: Teleostei) influenced growth, metamorphosis and alkaline protease activity
Authors: Da Silva-Souza Maria Fernanda , Sugai Juliet Kiyoko , Tsuzuki Mônica Yumi
Published: June 2021

The barber goby Elacatinus figaro is considered endangered due to overexploitation by the ornamental industry. Farming marine ornamental fishes, especially the threatened ones, can be one of the measures to minimize the pressure on the natural stocks. Among the priority issues for their production is the determination of the most appropriate feeding management. The feeding protocol commonly used in the larviculture of barber goby, when the start of Artemia sp. offer occurred at the 18th DAH (days after hatching) (treatment T18), was modified, by anticipating brine shrimp supply in 6 days (treatment T12). Alkaline proteases activity, growth and metamorphosis of larvae were evaluated in both protocols. Juveniles at T12 showed higher weight (0.04 ± 0.001 g) and lower activity of total alkaline proteases (1.3 ± 0.2 mU mg-1 protein) compared to T18 (0.02 ± 0.001 g; 2.8 ± 0.4 mU mg-1 protein, respectively). With anticipation of brine shrimp, the commencing and end of larval transformation was observed earlier (at 24 and 34 DAH, respectively) in comparison to those with the supply of Artemia sp. at 18 DAH (27 and 41 DAH, respectively). Thus, the Artemia sp. anticipation was beneficial during the larviculture of the barber goby, considering that larvae reached metamorphosis earlier.
Research on the river shrimps of the genus Macrobrachium (Bate, 1868) (Decapoda: Caridea: Palaemonidae) with known or potential economic importance: strengths and weaknesses shown through scientometrics
Authors: Chong-Carrillo Olimpia , Vega-Villasante Fernando , Arencibia-Jorge Ricardo , Akintola Shehu L. , Michán-Aguirre Layla , Cupul-Magaña Fabio G.
Published: June 2021

This study revealed that the scientific interest in the genus Macrobrachium was not restricted to a biological point of view, but included also social and economic aspects. Many species of the genus are subject of traditional fisheries and culture worldwide. Several research groups across the globe have developed projects in various subject areas on commercial or non-commercial native species of this genus. This investigation aimed to contribute to the development of the genus Macrobrachium research through a scientometric study. The study was based on publications (1980 to 2013) registered in the following databases: Biological Abstracts, ISI Web of Science, SciELO Citation Index, BioOne, Science Direct, Scopus, and Redalyc. A total of 2165 publications on Macrobrachium in the last 33 years were included in this analysis. The themes that yielded most posts were related to culture, nutrition/feeding, and genetics with almost 60% of the total. Publications concerning M. rosenbergii represented more than 60% of the total with the remaining 40% encompassing 22 other species. Analysis performed by geographical regions evidenced that Latin America produced 23% of the publications, South Asia 22%, and East Asia 16%. Brazil generated 65% of the percentage mentioned for the Latin American region. It is necessary to strengthen research on topics of basic biology, especially those of native species. This will allow rapid progress in the generation of production technologies sustained by a solid biological knowledge base.
Current state of knowledge on Virilastacus species (Crustacea, Decapoda, Parastacidae)
Authors: Rudolph Erich H.
Published: June 2021

The genus Virilastacus was created in 1991 to accommodate Parastacus araucanius Faxon, 1914. At present, Virilastacus comprises four burrowing species, three of which were described at the beginning of the XXI century, and biological knowledge about these species is mainly limited to taxonomic and distributional aspects. This review compiles published information about these species, together with other data available to the author in order to update the current state of biological knowledge and, in turn, to promote the conservation of these species. An upgraded diagnosis of the genus Virilastacus is provided, together with information related to each species with regard to: distinctive morphological traits, geographic distribution, habitat, burrow morphology, burrowing behavior, body size, sexual system, and state of conservation. Some aspects related to morphological adaptations to their burrowing life style, phylogenetic affinities and main threats to conservation are also discussed. It is concluded that biological knowledge about these four species is scarce and fragmentary; furthermore, they are currently under threat as a result of anthropogenic activities that are degrading and fragmenting their habitat.
Analysis of epibiont data in relation with the Debilitated Turtle Syndrome of sea turtles in Chelonia mydas and Lepidochelys olivacea from Concepción coast, Chile
Authors: Fernández Italo , Retamal Marco Antonio , Mansilla Miguel , Yáñez Francisco , Campos Víctor , Smith Carlos , Puentes Guillermo , Valenzuela Ariel , González Hernán
Published: June 2021

Epibionts on the surface of the skin and shell of a specimen of Chelonia mydas and three Lepidochelys olivacea found floating on the coast of Concepción, Chile, between June 2010 and December 2012, were analyzed. These epibionts were analyzed during the clinical inspection and the tissue changes related to its settlement, with filamentous algae around, were observed. Subsequently, the epibionts were identified by morphological observation. The knowledge about theses epibionts in Chile is reviewed and the potential occurrence of Debilitated Turtle Syndrome (DTS) in these turtles is discussed. The presence of sea turtles in the Chilean coast is considered a casual event, so there is little information on this issue. We propose it is necessary to carry out more studies on the association between turtles and epibionts because their identification, colonizing reptiles’ surface may give relevant information to a better understanding of different diseases, including DTS, that affect these marine reptiles and facilitates the development of strategies intended to recover their populations.
Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons
Authors: Salgado-Leu Italo , Tacon Albert G.J.
Published: June 2021

In cultivated aquatic organisms nutritional requirements are critical, not only for their impact on production techniques, but also, for their high incidence on production costs. There is limited knowledge on some species such as the southern Chilean freshwater crayfish, Samastacus spinifrons. In order to generate practical knowledge, a study was carried out to determine protein and carbohydrate content requirements. These factors were evaluated upon their effects on growth and survival of juveniles. For this purpose, individual weight, biomass gain, survival, and feed conversion parameters were measured. The assay was carried out in 42 days, It was conducted in a flow through system, using 21 plastic tanks of 10.6 L capacity. Each tank was seeded with 20 juveniles weighing 50 mg average each. A 3x2 factorial design was proposed with three protein contents (20, 30, 40%) and two carbohydrate contents (low: from 16.3 to 23.5% and high: from 34.6 to 35.8%). Six treatments and three replicates were performed. Individuals were fed on apparent satiation once a day. The diets formulated with 30% of protein and the two carbohydrate contents resulted in higher biomass increases, food conversion efficiencies over 26%, and specific growth rate of 0.78%, all displaying significant differences. Survival showed highly significant differences; in all diets were superior to 60%, however the diets with 30% of protein surpassed 90%.
Macrofaunal diversity and taxonomic distinctness in soft bottoms of the northern and southwestern Cuban shelf
Authors: Hidalgo Gema , Toledo Wilmer , Granados-Barba Alejandro
Published: June 2021

Diversity of macrofaunal groups in soft bottoms of the northern and southwestern Cuban shelf was assessed using taxonomic indices that depend on community structure, are independent of habitat type and sampling effort, and have a monotonic response to environmental disturbances. Taxa heterogeneity was significantly higher in sandy-muddy with vegetation, sandy with vegetation, and sandy with vegetation on hard bottom substrates. Biotopes diversity showed a gradient from smaller to greater particle size and from absence to presence of vegetation. Average taxonomic distinctness expected in these zones of the Cuban marine shelf is 92.5 with 95% confidence limits between 76.7 and 100. Sites with average taxonomic distinctness lower than 92.5 and outside the estimated confident limits can be considered environmentally deteriorated or favoring diversity of some particular groups. Dominant groups in this benthos fraction are crustaceans and polychaetes, which is consistent with studies in other tropical and temperate regions. These results constitute a baseline for environmental assessment and monitoring of macrofauna in Cuban soft bottoms, as a key component for marine ecosystems functioning.
Diversity and genetic origin of introduced channel catfish (Ictalurus punctatus Rafinesque, 1818) to central-west Mexico
Authors: Suarez-Salgado Diana , Herrera-Camacho José , Lara-Rivera Ana Laura , Parra-Bracamonte Gaspar Manuel
Published: June 2021

The channel catfish is an important aquaculture species in Mexico mostly managed in traditional production systems. The state of Tamaulipas has been the source of diverse populations of channel catfish in the country, however there is no documentary evidence of this. Therefore, the objective of this study was to confirm the genetic origin of populations of channel catfish (Ictalurus punctatus) of west central Mexico by microsatellite DNA markers. The study included four domestic populations from Michoacán, Zacatecas and Jalisco and two reference founder populations from Tamaulipas and Coahuila. The analysis was performed with a panel of 13 microsatellites. Some parameters of diversity and population structure were evaluated. The six populations showed excess of heterozygotes and a coefficient endogamy FIS ≤ -0.014. The analysis of gene structure was determined by a paired comparison populations, and indicated the 5.92% of variation among populations (FST= 0.059, P < 0.001). The assessment approaches identified the population of Tamaulipas as the most likely genetic origin of channel catfish populations currently used in the evaluated states.
Copper, zinc, cadmium and lead inputs and outputs in the maternity section of a commercial shrimp hatchery
Authors: Perea-Juárez Rosalba N. , Frías-Espericueta Martín G. , Páez-Osuna Federico , Voltolina Doménico
Published: June 2021

The aim of this work was to determine the amounts of copper, zinc, cadmium and lead which enter the tanks of the maternity section of a Mexican commercial hatchery, and those that are discharged to the environment. The most important inputs of Cu were chemicals for water treatment and disease prevention, feeds and the metal dissolved in influent water. Suspended solids and feeds were the two most important inputs of Zn, and feeds and chemicals were the main sources of Pb and Cd. Most metal concentrations may be considered safe for shrimp culture, but the concentrations of Cd of three formulated diets were close or above safe levels. The annual 2013 output of this hatchery was approximately 1.3x109 post-larvae, and the estimated metals discharged to the environment by the maternity section were 351 g of Cu, 1,190 g of Zn and 1.35 and 0.02 g of Pb and Cd, respectively. The amounts of Pb and Cd are equivalent to those of the fertilizers spread on between 0.5 and 1.5 ha of the agricultural land of Sinaloa State.
Reproduction of Carangoides vinctus (Perciformes: Carangidae) in the Mexican Central Pacific
Authors: Lucano-Ramírez Gabriela , Rivera-Rios Estrella G. , Ruiz-Ramírez Salvador , González-Sansón Gaspar , Perez-Toledo Alejandro
Published: June 2021

This study aims to determine some aspects of the reproduction of Carangoides vinctus, a species caught by the artisanal fishery on the south coast of Jalisco. The captures were made monthly with gillnets from January 1998 to December 2008. The organisms had total length of 17.0 to 41.2 cm, with females averaging 30.1 cm and 30.5 cm males. The sex ratio was 1.0: 1.1 males per females, which is not significantly different from the expected 1:1. A gonadal maturity scale of four stages for both sexes (immature, developing, spawning capable and post-spawning or spent) was used. In the first three stages of the ovary’s development, a septum dividing each lobe was present. In the analysis of oogenesis, seven oocyte development phases were identified and the oocytes developed asynchronously within the ovary. Based on the microscopic characteristics observed in the testis, it showed a lobular type development. The maximum values of the gonadosomatic index, the percentage of mature gonads and the oocyte diameter suggest that C. vinctus has a reproductive period from March to May. The length at sexual maturity (L50) was estimated at 26.04 and 23.77 cm for females and males, respectively; these sizes are lower than the average catch size in both sexes, suggesting that organisms are caught commercially when they have reached sexual maturity.