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Showing 201 - 400 of 911 Journals sorted alphabetically
Cuadernos de Administración (Universidad del Valle)     Open Access   (Followers: 3)
Cuadernos de Contabilidad     Open Access   (Followers: 3)
Cuadernos de Desarrollo Rural     Open Access   (Followers: 1, SJR: 0.154, CiteScore: 0)
Cuadernos de Economía     Open Access   (Followers: 1, SJR: 0.115, CiteScore: 0)
Cuadernos de Economía     Open Access   (Followers: 3)
Cuadernos de Economia - Latin American J. of Economics     Open Access   (Followers: 4)
Cuadernos de Historia     Open Access   (Followers: 2)
Cuadernos de Historia de la Salud Publica     Open Access  
Cuadernos de Medicina Forense     Open Access   (Followers: 2, SJR: 0.1, CiteScore: 0)
Cuadernos de Psicologia del Deporte     Open Access   (SJR: 0.423, CiteScore: 1)
Cuadernos del CENDES     Open Access   (SJR: 0.109, CiteScore: 0)
Cuadernos.info     Open Access   (SJR: 0.38, CiteScore: 0)
Cubo. A Mathematical J.     Open Access  
Cuestiones Constitucionales     Open Access   (Followers: 2, SJR: 0.1, CiteScore: 0)
Cuicuilco     Open Access   (Followers: 1)
Cuicuilco. Revista de Ciencias Antropológicas     Open Access   (Followers: 1)
Cultivos Tropicales     Open Access   (Followers: 1)
Cultura y Representaciones Sociales     Open Access   (Followers: 1)
Culturales     Open Access   (Followers: 3)
Dados - Revista de Ciências Sociais     Open Access   (SJR: 0.37, CiteScore: 0)
De Jure     Open Access   (Followers: 1)
DELTA : Documentação de Estudos em Lingüística Teórica e Aplicada     Open Access   (SJR: 0.133, CiteScore: 0)
Dementia & Neuropsychologia     Open Access   (Followers: 11, SJR: 0.205, CiteScore: 0)
Dental Press J. of Orthodontics     Open Access   (Followers: 5, SJR: 0.489, CiteScore: 1)
Desacatos     Open Access   (Followers: 1)
Desacatos : Revista de Antropología Social     Open Access   (Followers: 1)
Desarrollo y Sociedad     Open Access   (Followers: 3, SJR: 0.109, CiteScore: 0)
Diálogo Andino - Revista de Historia, Geografía y Cultura Andina     Open Access   (Followers: 1, SJR: 0.116, CiteScore: 0)
Diánoia     Open Access   (Followers: 1)
Dimensión Empresarial     Open Access  
Discusiones Filosóficas     Open Access   (Followers: 1)
Dynamis : Acta Hispanica ad Medicinae Scientiarumque Historiam Illustrandam     Open Access   (Followers: 3, SJR: 0.131, CiteScore: 0)
e-J. of Portuguese History     Open Access   (Followers: 2, SJR: 0.101, CiteScore: 0)
e-Pública : Revista Eletrónica de Direito Público     Open Access   (Followers: 1)
Earth Sciences Research J.     Open Access   (Followers: 1)
Eclética Química     Open Access   (Followers: 1)
Ecología en Bolivia     Open Access  
Economia Aplicada     Open Access   (SJR: 0.208, CiteScore: 0)
Economia e Sociedade     Open Access  
Economía Mexicana. Nueva Época     Open Access   (Followers: 1)
EconoQuantum     Open Access  
Educação & Sociedade     Open Access   (Followers: 3)
Educação & Realidade     Open Access  
Educação e Pesquisa     Open Access   (Followers: 1, SJR: 0.163, CiteScore: 0)
Educação em Revista     Open Access  
Educación Matemática     Open Access  
Educación Médica     Open Access   (Followers: 1, SJR: 0.236, CiteScore: 0)
Educación Médica Superior     Open Access   (Followers: 1, SJR: 0.237, CiteScore: 0)
Educación y Educadores     Open Access  
Educar em Revista     Open Access  
EDUMECENTRO     Open Access  
Eidos     Open Access   (SJR: 0.119, CiteScore: 0)
En-Claves del pensamiento     Open Access   (Followers: 1, SJR: 0.194, CiteScore: 0)
Encuentros     Open Access  
Ene : Revista de Enfermería     Open Access  
Enfermería Global     Open Access   (Followers: 3, SJR: 0.165, CiteScore: 0)
Enfermería Nefrológica     Open Access   (Followers: 1, SJR: 0.198, CiteScore: 0)
Enfoques     Open Access  
Engenharia Agrícola     Open Access   (SJR: 0.305, CiteScore: 1)
Engenharia Sanitaria e Ambiental     Open Access   (SJR: 0.218, CiteScore: 0)
Ensaio Avaliação e Políticas Públicas em Educação     Open Access   (Followers: 1, SJR: 0.254, CiteScore: 0)
Ensayos de Economía     Open Access   (Followers: 1)
Ensayos Revista de Economía     Open Access  
Entomologia y Vectores     Open Access   (Followers: 2)
Entre Ciencia e Ingeniería     Open Access   (Followers: 1)
Epidemiologia e Serviços de Saúde     Open Access  
Escritos de Psicología : Psychological Writings     Open Access   (Followers: 2)
Espacios en Blanco : Revista de educación     Open Access  
Estudios Atacameños     Open Access   (Followers: 2, SJR: 0.446, CiteScore: 1)
Estudios Constitucionales     Open Access   (Followers: 5, SJR: 0.319, CiteScore: 0)
Estudios de Cultura Maya     Open Access   (Followers: 2, SJR: 0.272, CiteScore: 0)
Estudios de Economía     Open Access   (SJR: 0.121, CiteScore: 0)
Estudios de historia moderna y contemporánea de México     Open Access   (SJR: 0.101, CiteScore: 0)
Estudios Economicos     Open Access  
Estudios Filologicos     Open Access   (SJR: 0.107, CiteScore: 0)
Estudios Fronterizos     Open Access   (Followers: 1)
Estudios internacionales     Open Access   (Followers: 5)
Estudios Pedagogicos (Valdivia)     Open Access   (Followers: 1, SJR: 0.338, CiteScore: 0)
Estudios Políticos     Open Access  
Estudios Sociales     Open Access   (Followers: 2)
Estudios sociales : Revista de alimentación contemporánea y desarrollo regional     Open Access   (Followers: 1)
Estudios Socioterritoriales : Revista de Geografía     Open Access  
Estudios y Perspectivas en Turismo     Open Access   (Followers: 2)
Estudos Afro-Asiáticos     Open Access   (Followers: 2)
Estudos Avançados     Open Access   (SJR: 0.232, CiteScore: 0)
Estudos de Psicologia (Campinas)     Open Access   (Followers: 1, SJR: 0.233, CiteScore: 0)
Estudos de Psicologia (Natal)     Open Access   (SJR: 0.117, CiteScore: 0)
Estudos Econômicos     Open Access   (SJR: 0.204, CiteScore: 0)
Estudos Históricos     Open Access   (Followers: 1)
EURE (Santiago) - Revista Latinoamericana de Estudios Urbano Regionales     Open Access   (SJR: 0.38, CiteScore: 1)
Ex aequo     Open Access  
FEM : Revista de la Fundación Educación Médica     Open Access  
Fides et Ratio : Revista de Difusión Cultural y Científica     Open Access   (Followers: 1)
Fisioterapia e Pesquisa     Open Access  
Fisioterapia em Movimento     Open Access  
Fitosanidad     Open Access  
Floresta e Ambiente     Open Access   (Followers: 1, SJR: 0.3, CiteScore: 0)
Folios     Open Access  
Food Science and Technology (Campinas)     Open Access   (Followers: 1, SJR: 0.467, CiteScore: 1)
Formación Universitaria     Open Access   (Followers: 4, SJR: 0.213, CiteScore: 1)
Frónesis     Open Access   (Followers: 1)
Frontera Norte     Open Access  
Gaceta Médica Boliviana     Open Access  
Gaceta Médica Espirituana     Open Access  
Galáxia (São Paulo)     Open Access  
Gayana (Concepcion)     Open Access   (SJR: 0.236, CiteScore: 0)
Gayana. Botanica     Open Access   (SJR: 0.234, CiteScore: 0)
Genetics and Molecular Biology     Open Access   (Followers: 15, SJR: 0.638, CiteScore: 2)
Geofísica internacional     Open Access   (SJR: 0.312, CiteScore: 1)
Gerokomos     Open Access   (Followers: 1, SJR: 0.257, CiteScore: 0)
Gestão & Produção     Open Access   (SJR: 0.156, CiteScore: 0)
Gestión y Política Pública     Open Access   (Followers: 2, SJR: 0.106, CiteScore: 0)
Hacia la Promoción de la Salud     Open Access  
Hallazgos     Open Access   (Followers: 1)
Hidrobiológica     Open Access   (SJR: 0.166, CiteScore: 0)
Historia     Open Access   (Followers: 2)
Historia (Santiago)     Open Access   (Followers: 1, SJR: 0.162, CiteScore: 0)
História (São Paulo)     Open Access   (SJR: 0.11, CiteScore: 0)
História, Ciências, Saúde - Manguinhos     Open Access   (Followers: 2, SJR: 0.144, CiteScore: 0)
Hoehnea     Open Access  
Horizonte Sanitario     Open Access   (Followers: 1)
Horizontes Antropológicos     Open Access   (Followers: 3, SJR: 0.233, CiteScore: 0)
Horticultura Brasileira     Open Access   (SJR: 0.605, CiteScore: 1)
HTS Theological Studies     Open Access   (Followers: 8, SJR: 0.448, CiteScore: 0)
Humanidades Médicas     Open Access  
IDESIA : Revista de Agricultura en Zonas Áridas     Open Access   (SJR: 0.223, CiteScore: 0)
Iheringia. Série Zoologia     Open Access   (Followers: 1, SJR: 0.26, CiteScore: 1)
Íkala : Revista de Lenguaje y Cultura     Open Access   (Followers: 1, SJR: 0.112, CiteScore: 0)
Image & Text     Open Access   (Followers: 1)
Index de Enfermeria     Open Access   (Followers: 7, SJR: 0.113, CiteScore: 0)
Indo-Pacific J. of Phenomenology     Open Access   (Followers: 1)
Infectio     Open Access   (SJR: 0.133, CiteScore: 0)
Información Tecnológica     Open Access   (SJR: 0.197, CiteScore: 0)
Ingeniare : Revista Chilena de Ingenieria     Open Access   (Followers: 1, SJR: 0.239, CiteScore: 0)
Ingeniería Electrónica, Automática y Comunicaciones     Open Access  
Ingeniería Hidráulica y Ambiental     Open Access  
Ingeniería Industrial     Open Access  
Ingeniería Mecánica     Open Access   (Followers: 4)
Ingenieria Mecánica. Tecnologia y Desarrollo     Open Access   (Followers: 3)
Ingeniería y Competitividad     Open Access  
Ingeniería y Desarrollo     Open Access  
Ingenieria y Universidad     Open Access   (Followers: 1, SJR: 0.161, CiteScore: 1)
Ingeniería, Investigación y Tecnología     Open Access   (Followers: 1)
Innovar     Open Access   (SJR: 0.118, CiteScore: 0)
Interações (Campo Grande)     Open Access  
Interface - Comunicação, Saúde, Educação     Open Access   (Followers: 1, SJR: 0.417, CiteScore: 0)
Intersticios Sociales     Open Access   (Followers: 1)
Intervención     Open Access   (Followers: 1)
Intervención Psicosocial     Open Access   (SJR: 0.381, CiteScore: 1)
Intl. Brazilian J. of Urology     Open Access   (Followers: 5, SJR: 0.367, CiteScore: 1)
Intl. J. of Morphology     Open Access  
Intl. J. of Odontostomatology     Open Access   (Followers: 1)
Intl. Law: Revista Colombiana de Derecho Internacional     Open Access   (Followers: 3)
Investigación Administrativa     Open Access   (Followers: 1)
Investigación Bibliotecológica     Open Access   (Followers: 6, SJR: 0.274, CiteScore: 0)
Investigación Económica     Open Access   (Followers: 4, SJR: 0.132, CiteScore: 0)
Investigación y Desarrollo     Open Access   (Followers: 1)
Investigación y Educación en Enfermería     Open Access   (Followers: 1, SJR: 0.198, CiteScore: 0)
Investigaciones Geográficas     Open Access   (SJR: 0.246, CiteScore: 0)
Investigaciones Marinas     Open Access  
Iteckne     Open Access  
Iuris Tantum Revista Boliviana de Derecho     Open Access  
Ius et Praxis     Open Access   (SJR: 0.283, CiteScore: 0)
Izquierdas     Open Access   (SJR: 0.188, CiteScore: 0)
Iztapalapa : Revista de ciencias sociales y humanidades     Open Access   (Followers: 1)
J. of Applied Oral Science     Open Access   (SJR: 0.645, CiteScore: 2)
J. of Applied Research and Technology     Open Access   (SJR: 0.255, CiteScore: 1)
J. of Coloproctology     Open Access   (SJR: 0.167, CiteScore: 0)
J. of Energy in Southern Africa     Open Access   (Followers: 3, SJR: 0.249, CiteScore: 1)
J. of Epilepsy and Clinical Neurophysiology     Open Access   (Followers: 7)
J. of Microwaves, Optoelectronics and Electromagnetic Applications     Open Access   (Followers: 11, SJR: 0.146, CiteScore: 1)
J. of Seed Science     Open Access   (Followers: 1)
J. of Soil Science and Plant Nutrition     Open Access   (Followers: 12, SJR: 0.823, CiteScore: 2)
J. of Technology Management & Innovation     Open Access   (Followers: 5, SJR: 0.271, CiteScore: 1)
J. of the Brazilian Chemical Society     Open Access   (Followers: 2, SJR: 0.357, CiteScore: 1)
J. of the Brazilian Society of Mechanical Sciences     Open Access   (Followers: 2)
J. of the Chilean Chemical Society     Open Access   (Followers: 2, SJR: 0.201, CiteScore: 1)
J. of the Mexican Chemical Society     Open Access   (Followers: 2, SJR: 0.214, CiteScore: 1)
J. of the Selva Andina Research Society     Open Access   (Followers: 3)
J. of the South African Institution of Civil Engineering     Open Access   (Followers: 2, SJR: 0.174, CiteScore: 0)
J. of the Southern African Institute of Mining and Metallurgy     Open Access   (Followers: 6)
J. of Theoretical and Applied Electronic Commerce Research     Open Access   (Followers: 1, SJR: 0.477, CiteScore: 2)
J. of Venomous Animals and Toxins     Open Access   (Followers: 2)
JISTEM : J. of Information Systems and Technology Management     Open Access   (Followers: 7)
Jornal Brasileiro de Nefrologia     Open Access   (SJR: 0.334, CiteScore: 1)
Jornal Brasileiro de Patologia e Medicina Laboratorial     Open Access   (SJR: 0.143, CiteScore: 0)
Jornal Brasileiro de Pneumologia     Open Access   (SJR: 0.448, CiteScore: 1)
Jornal Brasileiro de Psiquiatria     Open Access   (Followers: 3, SJR: 0.224, CiteScore: 0)
Jornal da Sociedade Brasileira de Fonoaudiologia     Open Access  
Jornal de Pneumologia     Open Access  
Jornal Vascular Brasileiro     Open Access   (SJR: 0.136, CiteScore: 0)
Justicia Juris     Open Access  
Kriterion: Revista de Filosofia     Open Access   (Followers: 1, SJR: 0.114, CiteScore: 0)
Kronos : Southern African Histories     Open Access   (Followers: 6)
La ventana. Revista de estudios de género     Open Access  
La zaranda de ideas     Open Access   (Followers: 1)
Laboreal     Open Access  
Lankesteriana     Open Access   (SJR: 0.458, CiteScore: 1)
Latin American Applied Research     Open Access   (Followers: 1)
Latin American J. of Aquatic Research     Open Access   (SJR: 0.289, CiteScore: 1)

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Latin American Journal of Aquatic Research
Journal Prestige (SJR): 0.289
Citation Impact (citeScore): 1
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ISSN (Online) 0718-560X
Published by SciELO Homepage  [911 journals]
  • Zootechnical performance and interaction between Penaeus schmitti
           Burkenroad, 1936 and Penaeus vannamei Boone, 1931 reared under laboratory
           conditions

    • Abstract: ABSTRACT To compare the zootechnical performance of the Brazilian native shrimp Penaeus schmitti and the exotic shrimp Penaeus vannamei, juveniles were grown under controlled conditions. Both species were simultaneously cultivated (monoculture) in separate 70 L plastic tanks at two different densities: 30 and 50 ind m-2. Also, in the other two treatments, both species were cultivated together (mixed), with and without feeding, at 30 ind m-2. During the experiment, P. vannamei generally showed a greater interest in food and voracity than P. schmitti. At harvest, for both stocking densities of monoculture treatments, the mean growth rate observed for P. vannamei was 1.0 g week-1, while P. schmitti achieved only 0.1 g week-1. The mean final weight was 10.4 ± 2.0 g; 10.7 ± 2.1 g for P. vannamei and 2.8 ± 0.3 g; 3.2 ± 0.3 g for P. schmitti, for respective densities of 50 and 30 ind m-2. In the mixed treatment with feeding, while P. vannamei reached 11.9 ± 1.4 g, P. schmitti reached only 2.6 ± 0.4 g in the same tank. The observed differences were 3.7 and 3.4 higher in favor of P. vannamei in the monoculture treatment, and up 4.5 times higher in the mixed treatment. Under strict fasting conditions, both species practiced predation/cannibalism among themselves. The results reflected the zootechnical advantages of P. vannamei, but also corroborated the negative effect that high densities and lack of natural food can exert over native species. The potential for P. schmitti cultivation and the possible impact of the escape of P. vannamei into the natural environment is discussed.
       
  • Population structure of Poecilia mexicana (native) and Poeciliopsis
           gracilis (non-native) in a subtropical river

    • Abstract: ABSTRACT Despite the increase of exotic species in bodies of water, studies on the population structure of coexisting native and exotic fish species are rare. We evaluated the population structure of the native Poecilia mexicana and non-native Poeciliopsis gracilis species in an environmental gradient and its relation to the habitat characteristics in the Jalpan River, located in the state of Queretaro, Mexico. We calculated size structure, sex ratio, gonad stage, and condition factor for both species. Visual-based habitat quality, riparian quality, and physical and chemical characteristics of water were also evaluated. A total of 322 individuals of P. gracilis and 762 of P. mexicana were captured with different fishing nets due to the habitat heterogeneity. Study sites were classified into three categories of habitat conditions: poor, marginal, and sub-optimal. P. mexicana females showed a complete structure of sizes in the poor habitat category. P. gracilis did not show a complete structure in any habitat category. The sub-optimal category of habitat conditions had the lowest number of specimens for both species. Poor category showed a sex ratio of 1:1 (females: males) for P. mexicana while in P. gracilis, females were more abundant than males (sex ratio 5:1). Fulton's factor was higher for P. mexicana than for P. gracilis. Our results showed that habitat quality of the river affected size structure, stages of development, and sex ratio of the two species, but did not show conclusive evidence of favored species or reproductive competition.
       
  • Economic valuation of sportfishing in the surroundings of Cerralvo Island,
           Baja California Sur, Mexico using the travel cost method

    • Abstract: ABSTRACT Los Cabos, Baja California Sur, Mexico, is a reference for sportfishing (SF). In this vein, a significant number of artisanal fishers from the communities surrounding Cerralvo Island-located 215 km from Los Cabos-have opted to offer SF as a tourist service in recent years. The SF has generated unevaluated economic activity in the area. Thus, stakeholders need to know this value to improve their management decision making. Therefore, this research aimed to make a valuation of the recreation service and factors that influence the demand of SF in Cerralvo Island and surrounding areas using the indirect travel cost method (TCM). For this purpose, 275 surveys were performed at the boat ramps in nearby towns. The estimated consumer surplus (EC) was USD 1,886 per visitor. Approximately 28,864 annual recreational sportfishing trips were recorded, so the total annual surplus was USD 54,437,504. The EC outperformed other national sites and was ≈140% higher than the highest valuation made for Los Cabos, which presumably derived from the differences in costs (v. gr., fishing charter, lodging). These values suggest the opportunity for the development of this activity in the study area.
       
  • Gonadal maturity of Crassostrea corteziensis cultivated in the
           Gulf of California

    • Abstract: ABSTRACT The gonadal maturation of the pleasure oyster Crassostrea corteziensis during four cultivation cycles (November 2004-June 2005, N4J5; August 2014-February 2016, A14F16; September 2015-December 2016, S15D16; September 2016-August 2017, S16A17) was studied in the southeastern Gulf of California, Mexico. Although C. corteziensis exhibited the typical reproductive phases (undifferentiated or resting, initial gametogenesis, advanced gametogenesis, maturity, spawning and post-spawning), the intensity of reproduction and the timing of the onset of the different phases of gonadal development varied in each cultivation cycle. Reproductive peaks were observed in different months (N4J5 in May, A14F16 in July, S15D16 in May and S16A17 in June) during spring and summer. Spawning correlated with temperature in the N4J5 and A14F16 cultivation cycles but it showed no correlation with chlorophyll-a concentration in any of the cultivation cycles. C. corteziensis presented an opportunistic continuous reproductive strategy with spawning occurring during several months of the year. The modification of the species' reproduction pattern could contribute to the natural settlement of larvae, increasing the natural production of this native oyster resource in the southeast of the Gulf of California, where it has been fished intensively.
       
  • Production of Penaeus vannamei in low salinity, using diets formulated
           with different protein sources and percentages

    • Abstract: ABSTRACT The present study was focused on assessing the effect of diets formulated with different sources and levels of protein on the production response of white leg shrimp Penaeus vannamei farmed at low salinity (3 g L-1). The protein sources were: soy meal (SM) and fish meal (FM), included at three levels: low (22-25%), medium (32-35%), and high (41-45%). A bioassay of 49 days was done in experimental tanks of 100 L (three tanks per treatment). Juvenile P. vannamei having a mean weight of 1.41 ± 0.30 g were stocked at a density of 100 ind m-3. Shrimp fed diets formulated with FM recorded significantly higher weight gain, specific growth rate (SGR), and protein assimilation efficiency rate (PER). Additionally, it showed a higher concentration of essential amino acids like methionine and threonine, and higher ash, calcium, iodine, phosphorous, and sodium content, which could favor the growth and survival of shrimp. Regression analysis showed that the optimum protein levels for diets formulated with SM and FM were 34.8 and 29.3%, respectively. These findings may help shrimp farmers to implement better feeding strategies for P. vannamei farmed at low salinity and on the use of alternative ingredients to substitute fish meal in the formulated feed.
       
  • Diet shifts of Rhizoprionodon terraenovae from the southern Gulf of
           Mexico: possible scenario by temperature changes

    • Abstract: ABSTRACT The current study examined the stomach contents of the Atlantic sharpnose shark (Rhizoprionodon terraenovae) in the southern Gulf of Mexico during 2015 to understand the relationship between diet and changes in sea surface temperature (SST). Prey-specific index of relative importance (%PSIRI), diet breadth (Bi), trophic level (TrL), and trophic overlap (PERMANOVA) were calculated between sexes, body size, and climatic seasons (dry, rainy and winter storm). The lowest temperature recorded in the area was during February (23.9°C), and the highest was during August (29.1°C). A total of 124 stomachs were analyzed, with 54.84% containing food. The trophic spectrum was composed of 32 identified prey, with demersal fish (Haemulon plumierii; %PSIRI = 22.82) and pelagic fish (Sardinella aurita; %PSIRI = 12.83) being the most important. According to the diet breadth (Bi= 0.002), Costello's graph, and trophic level (TrL = 4.2), R. terraenovae is a specialist tertiary consumer. PERMANOVA indicated significant trophic differences between sexes (F = 32.22; P < 0.05), body size (F = 13.68; P < 0.05), and among climatic seasons (F = 23.86; P < 0.05). Spearman's correlation indicated a negative relationship between the diversity of prey consumed by R. terraenovae and sea surface temperature (r = −0.75; P < 0.05). Therefore, diet for R. terraenovae is associated with SST, allowing for the development of possible scenarios related to climatic phenomena like climate change.
       
  • Compensatory growth in Nile tilapia Oreochromis niloticus: feed conversion
           ratio, size heterogeneity, and proximal composition

    • Abstract: ABSTRACT A feeding test was performed to evaluate compensatory growth in the Nile tilapia (Oreochromis niloticus) and to assess changes in feed conversion ratio (FCR), body condition, and carcass composition associated with the imposed feeding strategy. The experiment was carried out under two different stages, restricted (RS) and compensated (CS), with six weeks long each other. Three hundred juveniles of Nile tilapia (average weight of 16.4 ± 0.2 g) were divided into three treatments and one control. The control group was fed to apparent satiation four times a day in both stages. The RS treatments were based on 100% (RS100), 80% (RS80), and 60% (RS60) of a feeding chart, respectively. In the next six weeks, fishes from the CS treatments (CS100, CS80, and CS60) were then fed to apparent satiation four times a day. In the RS, the control group displayed the most considerable weight gained, but with a significant FCR. Nevertheless, in the CS, the previous restricted treatments (RC80 and RC100) showed a compensatory growth, with a smaller FCR than the control group. The restricted-compensated rations did not have a significant effect on the size heterogeneity; when the food is restricted, fish use to moisturize their tissue to compensate for the muscle loss until they receive more food. However, when the food restriction levels are too high, the weight gain, lipid, and protein levels do not recover as they were before. Thus, restricted (marginally) and compensatory feeding strategies provide evidence that growth rates of fishes can be regulated.
       
  • Incidental catch of marine organisms registered in the Chilean Antarctic
           krill fishery, years 2012-2016

    • Abstract: ABSTRACT Krill (Euphausia superba) catch is currently the most relevant fishery industry in Antarctic waters. This resource is a keystone species in the Antarctic food web, sustaining the contribution to the trophic ecology of many invertebrate and vertebrate species. To catch krill, part of the fleet in this fishery uses large mid-water nets that also retain a diversity of other organisms like plankton, meroplankton, and fish species as bycatch. Therefore, it is necessary to understand and evaluate the magnitude of this incidental catch, as well as the potential interactions between krill fishing gear with seabirds and mammals. To estimate the composition and extent of bycatch for this fishery included 784 samples of 25 kg and an equal number of 1 kg sub-samples obtained from Antarctic krill catches in Subarea 48, between years 2012 and 2016. A total of 15 fish species were identified along with the record of five other taxa and other unidentified specimens. The most relevant fish species bycaught by weight were mackerel icefish Champsocephalus gunnari, South Georgia icefish Pseudochaenichthys georgianus, and painted notie Lepidonotothen larseni. Additionally, 20 interactions with seabirds and nine interactions with Antarctic fur seals (Arctocephalus gazella) were registered. In the five years of operations, only three seabirds died, and only two individuals of A. gazelle caught by the net were killed.
       
  • Capturing, induced spawning, and first feeding of wild-caught
           Pseudopimelodus mangurus, an endangered catfish species

    • Abstract: ABSTRACT This study aimed to describe a procedure for sampling, reproduction, and first feeding of the Neotropical catfish Pseudopimelodus mangurus, an endangered fish species. Wild adult P. mangurus specimens were collected in the Mogi Guassu River and subsequently induced to spawn in laboratory conditions. After hand-stripping, the females, the average weight of the oocytes was 143 ± 1.6 g, with a fecundity of 718 ± 49.8 oocytes g-1. The diameter of the oocytes non-hydrated was 1226.3 ± 47.7 μm to 1761.2 ± 26.4 μm after hydration. The fertilization rates were 98.00 ± 0.63%, and the hatching rate was 68.94 ± 11.83%. The first feeding was made three days post-hatching with six different treatments, in which the best results arose with sequential feeding with Artemia nauplii, Astyanax altiparanae and Prochilodus lineatus larvae. This condition resulted in a final length of 2,012.7 ± 44.8 μm by the 10th day of the experiment, higher survival (65 ± 0.9%) and lower cannibalism rate (14 ± 0.3%). The data obtained in this study is important for the establishment of reproductive biotechniques, mass production of P. mangurus, and future establishment of ex-situ GenBank.
       
  • Trialing net illumination as a bycatch mitigation measure for sea turtles
           in a small-scale gillnet fishery in Ecuador

    • Abstract: ABSTRACT In Ecuador, one of the main hazards for threatened marine species, such as sea turtles, is small-scale fisheries bycatch. At a global scale, currently, bycatch reduction technologies (BRTs) are being tested in many coastal nations to mitigate this issue. Despite some advances in Ecuadorian efforts for wildlife protection, BRTs to reduce bycatch have yet to be assessed. The purpose of this study was to test the BRT of net illumination using violet light-emitting diodes (LEDs) as a mitigation measure to reduce sea turtle interactions in the small-scale driftnet fishery operating from the ports of Santa Rosa, Puerto Lopez and Jaramijo. A total of 146 pairs of experimental sets (control and illuminated panes) were deployed in all ports. A generalized linear mixed-effect model (GLMM) was employed to analyze the bycatch per unit of effort (BPUE) for sea turtles, and the catch per unit of effort (CPUE) for target species; for both control and illuminated panes. Thirty-two sea turtles from three species were observed captured: olive ridley Lepidochelys olivacea (n=18), green Chelonia mydas (n=13) and leatherback turtles Dermochelys coriacea (n=1). Turtle species-specific modeling showed bycatch of green turtles declined by 93% in illuminated nets compared with control, non-illuminated nets, whereas no significant difference between control and illuminated nets was observed for olive ridley turtles. The catch per unit effort of the pelagic fish species including skipjack tuna, yellowfin tuna, mahi-mahi, thresher shark and smooth hammerhead shark was not affected by net illumination. Our results represent the first evaluation of the effects of net illumination using LEDs on reducing marine turtle bycatch in Ecuadorian small-scale driftnet fisheries. Despite its relatively small sample size, these results could be used by fisheries managers to support the implementation or further testing of this BRT in gillnet fisheries along the Ecuadorian coast.
       
  • High-throughput sequencing of the 16S rRNA gene to analyze the gut
           microbiome in juvenile and adult tropical gar (Atractosteus tropicus)

    • Abstract: ABSTRACT Tropical gar (Atractosteus tropicus) is freshwater and estuarine fish, inhabiting the Earth since the Mesozoic era and undergoing limited physiological variation ever since. Besides its recognized cultural and scientific relevance, the species has seen remarkable growth in its economic impact due to pisciculture. In this study, we present the first report of the whole taxonomic composition of microbial communities in gut contents in juveniles and adults of A. tropicus, by sex and origin (wild and cultivated). For this study, 508 genera were identified, with the most and least abundant being Cetobacterium and Paludibacter, respectively. Fusobacteria, Proteobacteria, Firmicutes, and Bacteroidetes phyla are the core gut microbiome of A. tropicus juvenile and adult by sex and origin. Deinococcus-Thermus phylum sequence was only identified in wild-type males. In the phylogenetic trees reconstruction Lactococcus lactis strains CAU929 and CAU6600, Cp6 and CAU9951, Cetobacterium strain H69, Aeromonas hydrophila strain P5 and WR-5-3-2, Aeromonas sobria strain CP DC28 and Aeromonas hydrophila were identified, some of them with probiotic potential within the three dominant phyla in core gut microbiome in A. tropicus adults, especially in wild-type organisms. Myroides genus was recognized in microbiota gut of the cultivated juvenile A. tropicus. Nevertheless, Alpha diversity indicated that the highest gut microbiota abundance and richness is found in cultivated juvenile and wild-type adult A. tropicus female, rather than adult wild-type males and the least gut microbiota abundance and richness is found in a cultivated adult of A. tropicus for both sexes.
       
  • The effects of acute oxygen changes on heart rate in the freshwater crab
           Poppiana dentata ()

    • Abstract: ABSTRACT Heart rate is a key physiological feature that can be used to assess the response of organisms to changing environmental conditions in aquatic habitats, such as acute fluctuations in oxygen levels and hypoxic conditions. This experiment, therefore, investigated cardiac responses in a freshwater brachyuran species, Poppiana dentata, exposed to low oxygen levels. Heart rate was derived from beats per minute (bpm) signals (n = 576) using an infrared, non-invasive technique over a 96 h period, under different dissolved oxygen (DO) conditions. These involved three regimes: normoxic (6.8 ± 0.1 mg L-1), decreasing DO to hypoxic levels (6.2 to 1.7 mg L-1), and recovery with normoxic levels (6.3 ± 0.1 mg L-1). Changes in heart rates among the three regimes were significant (P < 0.05); reflecting the shift in heart rate during different conditions of oxygen availability, normoxic (59 to 61 bpm), declining DO (54 to 62 bpm) and recovery DO (53 to 64 bpm). Additionally, the normal rhythmicity of heart rates under the normoxic condition was not maintained throughout most of the declining DO and recovery periods. P. dentata has demonstrated cardiac compensations in heart rate during low oxygen levels, providing insight into the species cardiac physiology.
       
  • New records and morphometry of the Atlantic sixgill shark Hexanchus
           vitulus in the Caribbean coast of Guatemala

    • Abstract: ABSTRACT The present study constitutes the first records and morphometry of Hexanchus vitulus on the Caribbean coast of Guatemala. A total of 10 Atlantic six-gill sharks were captured by artisanal fishers during 2015-2019, showing a sex ratio of 2.3:1 (males:females) and a total length that ranges 61-165 cm. Morphometric measurements are provided for future comparisons in other coastal regions. Recorded sharks corresponded mostly to sexually mature individuals, which differs from that reported for different areas of the Caribbean.
       
  • First record and DNA barcode for Ocyurus chrysurus (Lutjanidae) from a
           coastal lagoon in the southwestern Gulf of Mexico

    • Abstract: ABSTRACT A single sub-adult specimen of yellowtail snapper, Ocyurus chrysurus (Bloch, 1791) of 76.08 mm total long (TL) and weighing 4.38 g, was caught on June 7, 2013 over a sandy habitat in the coastal lagoon of La Mancha, Veracruz, Mexico. The capture of O. chrysurus represents a first record for the lagoon and one of the few records for the estuarine systems of the southwestern Gulf of Mexico, even though this species is typical of habitats associated with coral reefs. Similarly, the reported sequence of the mitochondrial COI gene is also the first record of the species for coastal lagoons of this region. Other sequences of the same species were used to evaluate the haplotypic diversity in the western Atlantic Ocean.
       
  • Niche modeling remarks of Luidia senegalensis (Lamarck, 1816) (Asteroidea,
           Luidiidae) after 30 years of its first capture in the northeastern
           Brazilian coast

    • Abstract: ABSTRACT After more than 30 years of species' first capture on the Brazilian northeast coast, we report the second occurrence of the starfish Luidia senegalensis with niche modeling remarks on its distribution. Bottom trawl net collected specimens with artisanal fishery boat in Rio Grande do Norte State, northeast Brazil. It was noted the existence of a large number of regions, with high suitability for the occurrence of this species, in South America taking into account the ecological niche modeling, when compared to North and Central American continents. Benthic salinity range, calcite, and benthic minimum temperature were the most relevant for modeling. The northeastern, eastern, and southeastern Brazil ecoregions showed the most considerable amount of areas with high suitability for L. senegalensis. The niche modeling revealed essential aspects of the species and its distribution, raising concerns with regards to its future stability.
       
  • Length-weight and length-length relationship for three marine fish species
           of commercial importance from southwestern Atlantic Ocean coast

    • Abstract: ABSTRACT Length-weight (LWR) and length-length (LLR) relationships were described for three marine fish species Odontesthes argentinensis (Valenciennes, 1835), Urophycis brasiliensis (Kaup, 1858) and Brevoortia aurea (Spix & Agassiz, 1829) from the southwestern Atlantic Ocean coast, among sampling sites between 36 and 38°S. These species have commercial importance in fisheries. Latitudinal change in LWR could suggest the existence of different subpopulations throughout their distribution ranges. A total of 2,167 specimens were collected between August 2015 and October 2018 using lift nets (mostly 10 mm mesh size) and fishing rods 100-200 m offshore. Both relationships were highly significant (P < 0.0001) for all species and produced robust coefficients of determination (R2 > 0.94). The latitudinal trend of a and b parameters of LWR showed different patterns for each species. This study provides a new maximum length for B. aurea and describes the variation of the regression parameters. New length-length relationships of these species were reported.
       
  • Temporal variation in reproductive success and the effects of differential
           parental care on the progeny of fish with demersal eggs

    • Abstract: ABSTRACT A paternity test based on microsatellite analysis of eggs under the parental care of a bourgeois male Pacific sergeant major, Abudefduf troschelii, included gametes from five females and two parasitic males. The nest area was monitored for five days to evaluate variation in reproductive success, and an approximately 300% increase occurred on the first and second days after new oviposition followed by a more than 300% reduction from the second to fifth days due to predation or filial cannibalism. Finally, the egg area on the last day corresponded to the initial nest area, suggesting selective care by the male.
       
 
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