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Caracterización del perfil bioquímico del salmón del atlántico salmo salar sanos, y serovariación ante desafío con virus isa y piscirickettsia salmonis
(Universidad de Chile, 2018)
mayores amenazas para la industria acuícola nacional son las pérdidas producidas principalmente por enfermedades, disponer de herramientas complementarias a las de rutina, que puedan detectar precozmente alteraciones en la condición sanitaria de los peces...
Aquaculture production has grown at an accelerated rate in recent decades, but this rapid growth has facilitated the increase in the prevalence and incidence of infectious and contagious diseases in aquaculture. If we consider that one of the greatest threats for the national aquaculture industry are the losses produced mainly by diseases, to have complementary tools to those of routine, that can detect early alterations in the sanitary condition of the fish that are being cultivated. The exploration of blood biochemistry is a tool that allows us to detect early alterations, since it reveals changes that are previous to an organic deterioration, being an excellent predictor of the physiological state of the fish, alterations of the metabolism and the presence or absence of a pathological condition. The objective of this work was to determine normal reference ranges for blood biochemical parameters in Atlantic salmon. Also, to investigate the variations in the circulating levels of the analytes contemplated in this study, when the fish deal with diseases such as, for example, infectious anemia virus of the salmon and the bacterium of the Piscirickettsia salmonis. The biochemical variables considered in this study were total proteins, albumin, cholesterol, triglycerides, glucose, urea, creatinine, calcium, phosphorus, magnesium, aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine kinase (CK). A Wiener Lab Metrolab 2300 auto-analyzer was used for its determination. Through this study it was possible to establish variations in the circulating levels of blood biochemical parameters between healthy and sick fish. Therefore, the evaluation of the biochemical profiles provides valuable information on the health status of the fish and allows to investigate changes in the circulating levels of the analytes prior to an evident clinical deterioration....
Aquaculture production has grown at an accelerated rate in recent decades, but this rapid growth has facilitated the increase in the prevalence and incidence of infectious and contagious diseases in aquaculture. If we consider that one of the greatest threats for the national aquaculture industry are the losses produced mainly by diseases, to have complementary tools to those of routine, that can detect early alterations in the sanitary condition of the fish that are being cultivated. The exploration of blood biochemistry is a tool that allows us to detect early alterations, since it reveals changes that are previous to an organic deterioration, being an excellent predictor of the physiological state of the fish, alterations of the metabolism and the presence or absence of a pathological condition. The objective of this work was to determine normal reference ranges for blood biochemical parameters in Atlantic salmon. Also, to investigate the variations in the circulating levels of the analytes contemplated in this study, when the fish deal with diseases such as, for example, infectious anemia virus of the salmon and the bacterium of the Piscirickettsia salmonis. The biochemical variables considered in this study were total proteins, albumin, cholesterol, triglycerides, glucose, urea, creatinine, calcium, phosphorus, magnesium, aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine kinase (CK). A Wiener Lab Metrolab 2300 auto-analyzer was used for its determination. Through this study it was possible to establish variations in the circulating levels of blood biochemical parameters between healthy and sick fish. Therefore, the evaluation of the biochemical profiles provides valuable information on the health status of the fish and allows to investigate changes in the circulating levels of the analytes prior to an evident clinical deterioration....
Análisis comparativo de variables biométricas y estimación de la abundancia de Orestias ascotanensis Parenti, 1984 en dos vertientes con estructura de hábitat diferente en el salar de Ascotán
(Universidad de Chile, 2016)
sistema. En este estudio se escogieron dos vertientes (6 y 11) con estructura de hábitat y efecto antrópico diferente, en las cuales se eligieron tres sectores relativamente comparables. Para la captura de los peces, se dispuso de trampas de botellas o...
Ascotán salar (21º30'37''S; 68º16'31"0), is located at 3720 meters above sea level, close to the city of Calama. In this high Andean habitat, lives the native endemic fish Orestias ascotanensis Parenti in the springs of this system. In this study we selected two springs (6 and 11) with different habitat structure and anthropic influence. In both we selected three relatively comparable sites. For the fish capture, we used bottle traps or "minnow traps" and gill net enclosures of 25 m2 for the relative abundance estimation, biometrics variables analysis (total weight and standard length and Orestias population density. In relation with the relative abundance in the bottle traps, we obtained a total of 41 fish in spring 6 and 61 at spring 11. A nested analysis of variance (ANOVA) did not show significative differences between both springs (p=0,58), and also among sectors (p=0,27). Among the analysis of biometric variables, we compared the standard length (by ANOVA), of the measured fish (156 at spring 6 and 129 at spring 11). This also did not show differences between springs (p=0,79). But when comparing "total weight" between springs, using the standard length as a covariable, the analysis indicated contrasting weights, greater in the fish of the spring 6 in relation to the fish of spring 11 (p<0,001). We used diverse methods to estimate the population density of Orestias in the three 25 m2 corresponding nets quadrants (maximum likelihood, Leslie estimator and the general remotion Otis method). At spring six there were obtained similar results with both methods. It was obtained around 380 Orestias by 25 m2, meanwhile at spring 11; we obtained a value of 100 Orestias at 25 m2. It can be concluded that there are xiv differences between these springs since they present different anthropic influence and have different habitat. Although we did not find differences in relative abundance neither at the standard length, the difference was shown when comparing the total weight in relationship with a specific longitude....
Ascotán salar (21º30'37''S; 68º16'31"0), is located at 3720 meters above sea level, close to the city of Calama. In this high Andean habitat, lives the native endemic fish Orestias ascotanensis Parenti in the springs of this system. In this study we selected two springs (6 and 11) with different habitat structure and anthropic influence. In both we selected three relatively comparable sites. For the fish capture, we used bottle traps or "minnow traps" and gill net enclosures of 25 m2 for the relative abundance estimation, biometrics variables analysis (total weight and standard length and Orestias population density. In relation with the relative abundance in the bottle traps, we obtained a total of 41 fish in spring 6 and 61 at spring 11. A nested analysis of variance (ANOVA) did not show significative differences between both springs (p=0,58), and also among sectors (p=0,27). Among the analysis of biometric variables, we compared the standard length (by ANOVA), of the measured fish (156 at spring 6 and 129 at spring 11). This also did not show differences between springs (p=0,79). But when comparing "total weight" between springs, using the standard length as a covariable, the analysis indicated contrasting weights, greater in the fish of the spring 6 in relation to the fish of spring 11 (p<0,001). We used diverse methods to estimate the population density of Orestias in the three 25 m2 corresponding nets quadrants (maximum likelihood, Leslie estimator and the general remotion Otis method). At spring six there were obtained similar results with both methods. It was obtained around 380 Orestias by 25 m2, meanwhile at spring 11; we obtained a value of 100 Orestias at 25 m2. It can be concluded that there are xiv differences between these springs since they present different anthropic influence and have different habitat. Although we did not find differences in relative abundance neither at the standard length, the difference was shown when comparing the total weight in relationship with a specific longitude....
Plan de negocio vacunadora automática de peces para la industria acuícola
(Universidad de Chile, 2017)
permitirá aumentar la capacidad de vacunación, reducir los costos, y mejorar el proceso de vacunación.
Dentro de los objetivos generales para desarrollar el proyecto es elaborar un plan de negocios orientado a la vacunación automática de peces en los centros...
Cuantificación de la alteración hidrológica y recomendación de régimen hidrológico, favorecer el servicio ecosistémico de producción de peces, en la parte alta del río Paraná, Brasil
(Universidad de Chile, 2020)
logren mantener, en algún grado, un régimen de caudales que permita sostener la diversidad del hábitat acuático aguas abajo. Este trabajo tiene como fin favorecer específicamente el servicio ecosistémico de producción de peces, debido a que su pesca es el...
Exploración de los mecanismos genéticos involucrados en la evolución de la dentición faríngea en peces óseos.
(Universidad de Chile, 2021)
esta diversidad, se pueden encontrar dientes no solo en la región oral, sino también en la región faríngea, como el sistema de mandíbulas faríngeas en teleósteos y otros peces de aleta radiada (Actinopterygii). Estas mandíbulas faríngeas poseen dientes...
One of the most distinct characteristics of jawed vertebrates (Gnathostomata) is the presence of teeth. Teeth display enormous morphological diversity in different groups arising from common ancestral structures. Within this diversity, teeth can be found not only on the oral region, but also in the pharyngeal region, such as the pharyngeal jaw apparatus of teleosts and other ray finned fishes (Actinopterygii). These pharyngeal jaws possess large teeth comparable to those on the oral jaws and also share specific molecular markers of tooth development. Changes in the developmental expression patterns of morphogens are an important source of morphological evolution. In turn, these patterns of expression are driven by transcription factors and regulatory sequences in the genome. Thus, exploring the link between morphological changes throughout vertebrate dentition evolution with the distribution of certain genetic elements in genome databases is an interesting endeavor. However, there is currently no consensus on the point of origin of these pharyngeal teeth, with the idea that they may predate even oral teeth being prevalent. To shed light on this subject, a review of the morphological literature was undertaken, to establish analyses in a comparative phylogenetic context. This review revealed the origin of pharyngeal dentition, in the form of tooth plates with small teeth on the pharyngeal arches towards the origins of crown Osteichthyes. Later, these teeth enlarged in size on the posteriormost arches in some Actinopterygii lineages, forming the teeth of the pharyngeal jaw apparatus. To evaluate the correspondence of these morphological changes with the appearance of genetic mechanisms, a survey on genome databases of elements involved in both oral and pharyngeal tooth development in teleosts was undertaken. For this analysis, a conserved region within an enhancer for the dlx2 gene and the presence of the eve1 gene were considered. It was found that these genetic elements originated towards the origin of crown Osteichthyes, coinciding with the appearance of pharyngeal teeth. Furthermore, the phylogenetic distribution of the dlx2 enhancer region supports a late origin of the gene’s odontogenic role, starting in Osteichthyes as opposed to an ancestral origin in Gnathostomata. On the other hand, the presence of a previously undescribed eve1 gene was found on the coelacanth Latimeria chalumnae, changing the most likely position of the loss of this gene in the lineage leading to tetrapods, allowing for the possibility that it may have been present in early tetrapodomorphs. In conclusion, pharyngeal teeth and novel odontogenesis mechanisms involving dlx2 and eve1 originated towards the origin of crown Osteichthyes, at a much later time than previously suggested. Using a dual comparative and bioinformatic approach, interesting hypotheses regarding the evolution of pharyngeal teeth were established and can be tested through experimental methods in the future....
One of the most distinct characteristics of jawed vertebrates (Gnathostomata) is the presence of teeth. Teeth display enormous morphological diversity in different groups arising from common ancestral structures. Within this diversity, teeth can be found not only on the oral region, but also in the pharyngeal region, such as the pharyngeal jaw apparatus of teleosts and other ray finned fishes (Actinopterygii). These pharyngeal jaws possess large teeth comparable to those on the oral jaws and also share specific molecular markers of tooth development. Changes in the developmental expression patterns of morphogens are an important source of morphological evolution. In turn, these patterns of expression are driven by transcription factors and regulatory sequences in the genome. Thus, exploring the link between morphological changes throughout vertebrate dentition evolution with the distribution of certain genetic elements in genome databases is an interesting endeavor. However, there is currently no consensus on the point of origin of these pharyngeal teeth, with the idea that they may predate even oral teeth being prevalent. To shed light on this subject, a review of the morphological literature was undertaken, to establish analyses in a comparative phylogenetic context. This review revealed the origin of pharyngeal dentition, in the form of tooth plates with small teeth on the pharyngeal arches towards the origins of crown Osteichthyes. Later, these teeth enlarged in size on the posteriormost arches in some Actinopterygii lineages, forming the teeth of the pharyngeal jaw apparatus. To evaluate the correspondence of these morphological changes with the appearance of genetic mechanisms, a survey on genome databases of elements involved in both oral and pharyngeal tooth development in teleosts was undertaken. For this analysis, a conserved region within an enhancer for the dlx2 gene and the presence of the eve1 gene were considered. It was found that these genetic elements originated towards the origin of crown Osteichthyes, coinciding with the appearance of pharyngeal teeth. Furthermore, the phylogenetic distribution of the dlx2 enhancer region supports a late origin of the gene’s odontogenic role, starting in Osteichthyes as opposed to an ancestral origin in Gnathostomata. On the other hand, the presence of a previously undescribed eve1 gene was found on the coelacanth Latimeria chalumnae, changing the most likely position of the loss of this gene in the lineage leading to tetrapods, allowing for the possibility that it may have been present in early tetrapodomorphs. In conclusion, pharyngeal teeth and novel odontogenesis mechanisms involving dlx2 and eve1 originated towards the origin of crown Osteichthyes, at a much later time than previously suggested. Using a dual comparative and bioinformatic approach, interesting hypotheses regarding the evolution of pharyngeal teeth were established and can be tested through experimental methods in the future....
Modificación de las condiciones de crianza y crecimiento en etapa larval y juvenil en pez cebra (Danio rerio)
(Universidad de Chile, 2011)
donde los resultados podrían aplicarse a peces de importancia acuícola. Un requisito indispensable para utilizar el pez cebra como modelo en acuicultura es generar un gran número de peces adultos, sin embargo, no se han establecido los protocolos...
The zebrafish (Danio rerio) is one of the most common vertebrates as a model organism in molecular and developmental biology, physiology and toxicology. Recently it has been proposed as a model organism in studies of nutrition and growth. However, have not been established protocols for larval rearing which makes it difficult to generate large numbers of adult fish, a prerequisite for using zebrafish as a model for aquaculture. Recently it has been proposed as a model organism in studies of nutrition and growth where the results could be applied to important fish in aquaculture. A prerequisite for using zebrafish as a model for aquaculture is to generate a large numbers of adult fish, however, have not established appropriate protocols for larval rearing which makes the task of generating plenty of adults. The survival of the larvae depends on both the supply and physicochemical conditions of the environment where they are, however, most of these parameters are relatively established only for the maintenance of adult fish. For example, the level of dissolved oxygen in the water in the larval stage has not been described. The aim of this study was to determine the optimal conditions for rearing larval zebrafish from 8 to 28 days post fertilization (dpf), once the transition occurs from larva to juvenile, and know the growth of the larvae until 98 dpf, prior to sexual maturity. We evaluated the survival of larvae exposed to a condition of no aeration and constant aeration in 24 families of fish during the first 28 dpf. We compared the growth rate of fish under constant aeration from 28 dpf to 98 dpf, fed with two experimental diets differing in protein source (animal v/s plant). Additionally, growth curves were obtained for fish fed with experimental diet based on animal protein and commercial food. The results indicate that increased mortality of fish larvae register under no aeration condition with a mortality 52.81% versus 4.95% in that population under constant aeration. In both trials, the highest mortality was recorded between 12 and 14 dpf, in addition to the treatment without aeration showed an increase in mortality between 22 and 25 dpf, probably due to environmental hypoxic conditions. Moreover, the populations fed diets differing in protein source had significantly higher values in weight and length in those fish fed with animal protein versus those fed plant protein (181.964 ± 62.952 mg and 15.963 ±1.862 mm versus 135.204 ± 55.701 mg versus 14.227 ± 2.340 mm). By comparing the growth curves for fish fed diet based on animal protein and commercial diet were fitted to potential model ( for growth, where that population fed commercial diet that showed greatest increases in weight and length (P > 0.05)....
The zebrafish (Danio rerio) is one of the most common vertebrates as a model organism in molecular and developmental biology, physiology and toxicology. Recently it has been proposed as a model organism in studies of nutrition and growth. However, have not been established protocols for larval rearing which makes it difficult to generate large numbers of adult fish, a prerequisite for using zebrafish as a model for aquaculture. Recently it has been proposed as a model organism in studies of nutrition and growth where the results could be applied to important fish in aquaculture. A prerequisite for using zebrafish as a model for aquaculture is to generate a large numbers of adult fish, however, have not established appropriate protocols for larval rearing which makes the task of generating plenty of adults. The survival of the larvae depends on both the supply and physicochemical conditions of the environment where they are, however, most of these parameters are relatively established only for the maintenance of adult fish. For example, the level of dissolved oxygen in the water in the larval stage has not been described. The aim of this study was to determine the optimal conditions for rearing larval zebrafish from 8 to 28 days post fertilization (dpf), once the transition occurs from larva to juvenile, and know the growth of the larvae until 98 dpf, prior to sexual maturity. We evaluated the survival of larvae exposed to a condition of no aeration and constant aeration in 24 families of fish during the first 28 dpf. We compared the growth rate of fish under constant aeration from 28 dpf to 98 dpf, fed with two experimental diets differing in protein source (animal v/s plant). Additionally, growth curves were obtained for fish fed with experimental diet based on animal protein and commercial food. The results indicate that increased mortality of fish larvae register under no aeration condition with a mortality 52.81% versus 4.95% in that population under constant aeration. In both trials, the highest mortality was recorded between 12 and 14 dpf, in addition to the treatment without aeration showed an increase in mortality between 22 and 25 dpf, probably due to environmental hypoxic conditions. Moreover, the populations fed diets differing in protein source had significantly higher values in weight and length in those fish fed with animal protein versus those fed plant protein (181.964 ± 62.952 mg and 15.963 ±1.862 mm versus 135.204 ± 55.701 mg versus 14.227 ± 2.340 mm). By comparing the growth curves for fish fed diet based on animal protein and commercial diet were fitted to potential model ( for growth, where that population fed commercial diet that showed greatest increases in weight and length (P > 0.05)....
Efectos del cobre en larvas de pez cebra
(Universisdad de Chile, 2007)
El cobre es un ion esencial que participa como cofactor en una variedad de enzimas
metabólicas. Sin embargo un exceso de este metal produce radicales libres que son
tóxicos para las células y el organismo. Los peces han sido ampliamente usados para...
Análisis de la regulación de la actividad pesquera en Chile post Ley N° 20.657 del año 2013
(Universidad de Chile, 2022)
actividad pesquera en Chile, de manera
que antes de entrar de lleno al análisis jurídico, podamos conocer cómo funciona el mercado de la
extracción de peces, cuales son las principales normas que rigen a la pesca tanto en el plano nacional
5
como...