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En los peces, al igual que en los mamíferos, se ha visto una íntima comunicación entre los sistemas nervioso, endocrino e inmune. Esta comunicación bi-direccional es posible gracias a que las señales moleculares sintetizadas por células y tejidos de los tres sistemas son similares y en algún caso idénticas. Esta estrecha interrelación es fundamental, entre otras cosas, para hacer frente de manera coordinada y eficaz a las situaciones de estrés. El estrés se puede definir como cualquier situación que somete al organismo a unas condiciones fuera del rango fisiológico estable o normal (enfermedades, cambios extremos en las condiciones medio ambientales, etc.). El conjunto de cambios en los tres sistemas orgánicos que genera la situación de estrés como respuesta a dicha situación se conoce genéricamente como síndrome de adaptación general (SAG). Las situaciones de estrés en los peces y los mamíferos guardan gran similitud, aunque existen diferencias en cuanto a los órganos implicados y el tiempo de respuesta, siendo éste un factor importante para la recuperación de la homeostasis. Los parámetros utilizados para identificar los peces estresados son los relacionados con las diferentes fases de la respuesta al estrés: respuesta primaria (adrenalina y cortisol), secundaria (glucosa, lactato y iones del plasma) y las proteínas de fase aguda (APP); además de indicadores inmunes como los indicadores fagocíticos, las enzimas líticas del sistema alternativo del complemento, las aglutininas y los precipitinas (opsoninas, sobre todo lectinas), los anticuerpos naturales, los citoquinas, los quimiomoquinas y los peptidos anti-bacterianos. Todo ello cobra gran relevancia desde el punto de vista económico, por cuanto la producción industrial de recursos pesqueros (piscifactorías) muestra cada vez mayor importancia económica en todo el mundo debido al crecimiento de su demanda y a la creciente calidad del producto comercial. In fish, like in mammals, an intimate communication between the nervous, endocrine and immune systems has been observed. This bidirectional communication is possible thanks to the molecular signals synthesized by cells and tissues of the three systems are similar or in some cases identical. This intimate interrelation is fundamental, among other factors to cope, in coordinated and effective manner, with the stress situations. Stress can be defined as any situation that puts the organism under the conditions outside the stable or normal physiological range (extreme diseases, changes in the environmental conditions, etc.). The changes in the three regulatory systems that the stress situation generates as a response to this situation is known generically as the general adaptation syndrome (GAS). The stress situations in fish and the mammals keep great similarities, although there exist differences in terms of the organs involved and the response time, being this, an important factor for the recovery of the homeostasis. The parameters used to identify a stressed fish are the ones related to the different response phases after stress: primary response (adrenalin and cortisol), secondary (glucose, lactate and ions of the plasma) and the proteins of acute phase (APP). In addition, immune parameters like phagoctytosis indicators, lytic enzymes of the alternative system of the complement, the aglutinines and precipitines (opsonines, mainly lectines), the natural antibodies, the antibacterial cytokines, chemokines and peptides, may be indicative of stress episodes. All of it sows great relevance from the economic point of view, inasmuch as the industrial production of fishing resources (fish farms) anywhere in the world shows greater economic importance due to the growth of their demand and to the increasing quality of the commercial product.

The purpose of this booklet is to develop a functional prototype for an aquaponic system based on the conditions of the Las Quinchas village in the municipality of Otanche. This is done with the aim of contributing to the processes of the area's new rural development. La presente cartilla tiene como objetivo Formular un prototipo funcional para un sistema acuapónico a partir de las condiciones de la vereda las Quinchas del municipio de Otanche, a fin de aportar en los procesos de nueva ruralidad del territorio.

El trabajo se realizó en la Ciénaga Grande de Santa Marta en cuatro estaciones de muestreo en el período de febrero 1993 a enero 1994. Se capturaron en total 890 individuos de Bairdiella ronchus (Cuvier), en su gran mayoría con atarraya mediante el método de corral. Los rangos de tallas variaron entre 66 y 231 mm de longitud total y 3.5 a 156.2 g de peso total. Esta especie es típica estuarina, se distribuye en salinidades comprendidas entre 7.3 y 37.3 y se caracteriza como carnívora, y consumidor de tercer orden, pues se alimenta principalmente de peces y crustáceos (decápodos). De acuerdo con el índice de importancia relativa los peces son el alimento principal y los crustáceos el alimento secundario; durante la época seca consume principalmente peces y en época de lluvia crustáceos. Los juveniles y adultos se alimentan tanto de peces como de crustáceos. The work was carried out in the Ciénaga Grande de Santa Marta in four sampling stations in the period from February 1993 to January 1994. A total of 890 individuals of Bairdiella ronchus (Cuvier) were captured, the vast majority with cast nets using the corral method. . Size ranges varied between 66 and 231 mm in total length and 3.5 to 156.2 g in total weight. This species is typical estuarine, it is distributed in salinities between 7.3 and 37.3 and is characterized as carnivorous, and a third-order consumer, as it feeds mainly on fish and crustaceans (decapods). According to the relative importance index, fish are the main food and crustaceans are the secondary food; During the dry season it mainly consumes fish and in the rainy season crustaceans. Juveniles and adults feed on both fish and crustaceans.

La variabilidad genética del bagre rayado Pseudoplatystoma fasciatum fue estudiada a través del análisis de isoenzimas en 15 loci codificadores de proteínas en muestras de tejido hepático tomadas en tres localidades del río Magdalena. La distancia genética estándar D (0.00006-0.00041) y el índice de Fijación FST (0.006) sugieren que son muestras de un mismo linaje. Los valores promedio de heterocigocidad fueron muy bajos y no se encontró polimorfismo en ningún sistema enzimático. Los resultados soportan la idea de la existencia de una población panmictica favorecida por el aislamiento reproductivo generado por eventos geológicos durante la formación de la cuenca, por la ausencia de barreras geográficas infranqueables y el carácter migratorio de P. fasciatum. Sin embargo, debido a los sostenidos niveles de sobreexplotación que enfrenta el recurso y al evidente deterioro de la cuenca, surge el cuestionamiento en torno al impacto que puede estar ejerciendo la reducción en el tamaño poblacional sobre la pérdida de variabilidad genética. Se identificaron dos marcadores que pueden ser de gran utilidad para el monitoreo de la salud poblacional. The genetic variability of the striped catfish Pseudoplatystoma fasciatum was studied through isoenzyme analysis at 15 protein-coding loci in liver tissue samples taken in three locations of the Magdalena River. The standard genetic distance D (0.00006-0.00041) and the FST Fixation index (0.006) suggest that they are samples of the same lineage. The average heterozygosity values ​​were very low and no polymorphism was found in any enzyme system. The results support the idea of ​​the existence of a panmictic population favored by the reproductive isolation generated by geological events during the formation of the basin, by the absence of impassable geographical barriers and the migratory nature of P. fasciatum . However, due to the sustained levels of overexploitation faced by the resource and the evident deterioration of the basin, the question arises about the impact that the reduction in population size may be having on the loss of genetic variability. Two markers were identified that can be very useful for monitoring population health.

A core challenge in ecology is identifying the factors that determine species distribution and functional diversity of species assemblages. Reef fish are the most diverse group of vertebrates, form taxonomically rich and functionally diverse communities and represent a key source of food for humans. We examine regional distribution patterns of reef fish species richness and functional diversity and investigate how these are determined by historical, biogeographic, energetic, and anthropogenic factors. We compiled data from 3,312 underwater visual censuses performed at 122 locations comprising rocky and coral reefs along the Eastern Tropical Pacific (ETP). We used generalized linear mixed‐effects models (GLMMs) implemented in a Bayesian framework to investigate whether distance from quaternary refugia, distance from mainland, shelf area, primary productivity, sea surface temperature (SST), human population gravity, and conservation status influence reef fish species richness and functional diversity in the ETP. Species richness and functional richness (FRic) peaked towards the center of the ETP and our null model suggests that FRic followed a spatial pattern that would be predicted by species richness. Additionally, functional evenness (FEve) was highest at higher latitudes whereas functional dispersion (FDis) was homogeneous throughout the ETP. Species richness was negatively influenced by shelf area and distance from mainland, but positively influenced by SST and conservation status. FEve was influenced by human population gravity and FDis by shelf area. Reef fish species richness and functional diversity in the ETP exhibited a strong division within the region mainly mediated by SST and human population gravity. Our results also suggest that dominant species within small shelf areas share more common traits than dominant species in large areas. This study uncovers previously unknown regional patterns of reef fish functional diversity and provides new insights into how historical, biogeographic, energetic, and anthropogenic factors influence complementary biodiversity facets.

Selection shapes genetic diversity around target mutations, yet little is known about how selection onspecific loci affects the genetic trajectories of populations, including their genome-wide patterns of diversityand demographic responses. Here we study the patterns of genetic variation and geographic structure in aneotropical butterfly,Heliconius numata, and its closely related allies in the so-called melpomene-silvaniformclade. H. numata is known to have evolved an inversion supergene which controls variation in wing patternsinvolved in mimicry associations with distinct groups of co-mimics whereas it is associated to disassortativemate preferences and heterozygote advantage at this locus.We contrasted patterns of genetic diversity andstructure 1) among extant polymorphic and monomorphic populations of H. numata, 2) between H. numataand its close relatives, and 3) between ancestral lineages.We show that H. numata populations which carrythe inversions as a balanced polymorphism show markedly distinct patterns of diversity compared to allother taxa. They show the highest genetic diversity and effective population size estimates in the entireclade, aswell as a lowlevel of geographic structure and isolation by distance across the entire Amazon basin.By contrast, monomorphic populations of H. numata as well as its sister species and their ancestral lineagesall show lower effective population sizes and genetic diversity, and higher levels of geographical structureacross the continent. One hypothesis is that the large effective population size of polymorphic populationscould be caused by the shift to a regime of balancing selection due to the genetic load and disassortativepreferences associated with inversions. Testing this hypothesis with forward simulations supported theobservation of increased diversity in populations with the supergene. Our results are consistent with thehypothesis that the formation of the supergene triggered a change in gene flow, causing a general increasein genetic diversity and the homogenisation of genomes at the continental scale. International audience

Mangrove forests provide valuable ecosystem services to coastal communities across tropical and subtropical regions. Current anthropogenic stressors threaten these ecosystems and urge researchers to create improved monitoring methods for better environmental management. Recent efforts that have focused on automatically quantifying the above-ground biomass using image analysis have found some success on high resolution imagery of mangrove forests that have sparse vegetation. In this study, we focus on stands of mangrove forests with dense vegetation consisting of the endemic Pelliciera rhizophorae and the more widespread Rhizophora mangle mangrove species located in the remote Utría National Park in the Colombian Pacific coast. Our developed workflow used consumer-grade Unoccupied Aerial System (UAS) imagery of the mangrove forests, from which large orthophoto mosaics and digital surface models are built. We apply convolutional neural networks (CNNs) for instance segmentation to accurately delineate (33% instance average precision) individual tree canopies for the Pelliciera rhizophorae species. We also apply CNNs for semantic segmentation to accurately identify (97% precision and 87% recall) the area coverage of the Rhizophora mangle mangrove tree species as well as the area coverage of surrounding mud and water land-cover classes. We provide a novel algorithm for merging predicted instance segmentation tiles of trees to recover tree shapes and sizes in overlapping border regions of tiles. Using the automatically segmented ground areas we interpolate their height from the digital surface model to generate a digital elevation model, significantly reducing the effort for ground pixel selection. Finally, we calculate a canopy height model from the digital surface and elevation models and combine it with the inventory of Pelliciera rhizophorae trees to derive the height of each individual mangrove tree. The resulting inventory of a mangrove forest, with individual P. rhizophorae tree height information, as well as crown shape and size descriptions, enables the use of allometric equations to calculate important monitoring metrics, such as above-ground biomass and carbon stocks.

Following global trends, research to determine the presence and abundance of microplastics (MPs) in environmental matrices in Colombia has focused on the coastal and marine environments. However, little scientific information is available on the impact of this pollutant on wetlands and fish. In this study, we provided scientific data on the occurrence and abundance of MPs in water and fish from Tocagua Lake, an important wetland in the Colombian Caribbean, and the unique habitat of wild cotton-top tamarins (Saguinus oedipus). Water (72) and fish (228 individuals of six species) samples were collected during four sampling events and two climatic seasons (wet and dry). A total of 1174 microplastic particles were collected in water with an average abundance of microplastics at the six stations sampled during four sampling events of 0.96 ± 0.40 MPs/L, and 648 MPs were identified in the gastrointestinal tract of 191 individuals, corresponding to a frequency of occurrence of 83.7%. Black- and blue-colored fiber MPs were particles that predominated in both matrices (water and fish), and seven types of polymers were identified through attenuated total reflectance Fourier transform infrared spectroscopy analysis. The abundance, type, and color of MPs in water and fish were not significantly different between seasons.