The maintenance of a functional energy balance in ectothermic fauna could be challenging in a thermally disparate environment. Biochemical adaptations at the enzyme and membrane levels allows for a set compensatory mechanism that allow the individual to maintain an energetic surplus, thus allocating energy for growth and reproduction. The present work describes how the energetic machinery in the cell, particularly the mitochondrion, could be affected by temperature changes. More specifically, this work aimed to determine how environmental temperature affects the mitochondria energetic performance of fishes from disparate thermal regimes. Mitochondrial ATP production efficiency was evaluated in fishes from polar, tropical and subtropical regions. In polar fishes, mitochondria remained functional at temperatures well beyond whole organismal critical temperatures. On the other hand, tropical and subtropical teleosts exhibited a decrease in mitochondrial efficiency at temperatures commonly found during summer seasons. This remarkable variability of mitochondrial thermal sensitivity may restrict the energy allocated for growth and reproduction during the summer months in tropical and subtropical regions. The observed variation in the thermal window of tolerance of mitochondrial function in fishes provides further insight into how the energetic machinery responds to thermal changes, like those associated with warming trends in marine ecosystems. In addition, the reduced efficiency in mitochondrial function among teleosts from latitudinal gradients suggest that warm-adapted species are close to their upper tolerance range, and further warming trends could severely impact the energy budget of fishes.

O desenvolvimento ontogenético em peixes é considerado como uma das etapas mais importantes no fornecimento de informações para biologia do desenvolvimento, aquicultura e estudos taxonômicos. A Proteína Óssea Morfogenética 2 (BMP-2) é considerada uma molécula essencial como regulador no desenvolvimento embrionário e na formação óssea, sendo ainda pouco estudada em peixes. Neste trabalho, foram comparadas todas as fases do desenvolvimento de três espécies de peixes importantes da bacia do rio Pardo, curimbatá (Prochilodus hartii), piabanha (Brycon sp) e piau (Leporinus steindachneri). A superfície ovocitária, estádios e duração do desenvolvimento embrionário/larval foram classificados com a utilização de microscópio estereoscópio, havendo variações entre as espécies no desenvolvimento. A transformação dos alevinos também apresentaram variações, com 16 dias pós-eclosão em P. hartii, 5 dias em Brycon sp e 14 dias em L. steindachneri. Na imunohistoquímica, BMP-2 foi identificada na blastocele nas fases de blástula e gástrula; na formação da vesícula óptica, notocorda e somitos, na fase embrionária das espécies estudadas. Na fase larval e de juvenil, BMP-2 foi identificada na formação de brânquias, olhos, coração, estômago, intestino, fígado, nadadeiras, músculos e na ossificação em todas as espécies estudadas. Indivíduos adultos foram sacrificados, e depois de realizada a biometria, dissecados para mensuração dos órgãos internos e documentação fotográfica. Observou-se que o estômago de P. hartii tem forma de \"U\" com presença de uma estrutura semelhante a uma moela, enquanto em Brycon sp tem forma de \"J\" com presença de cecos pilóricos aderidos no piloro e em L. steindachneri, o mesmo possui forma de \"Y\" sem presença de cecos pilóricos. Esqueletos foram preparados através da técnica de maceração com insetos dermestídeos, sendo observadas diferenças, sendo interessante descrever que em P. hartii foram encontrados 4 ossos infraorbitais, 6 em Brycon sp e 4 em L. steindachneri. Conclui-se que os exemplares de P. hartii possuem hábito alimentar iliófago, enquanto Brycon sp e L. steindachneri são considerdados onívoros, baseado nos achados anatômicos e a expressão de BMP-2 está ligada com a morfogênese e organogênese na embriologia das espécies estudadas. / The ontogenetic development in fish is considered as one of the most important steps in providing information to developmental biology, aquaculture and taxonomic studies. The Bone Morphogenetic Protein 2 (BMP-2) is considered as a molecule essential for regulaton of embryonic development and bone formation, and has been poorly studied in fish. In this work, we have compared all the development phases of three important species of fish from the Pardo River basin, Curimbata (Prochilodus hartii) Piabanha (Brycon sp) and Piau (Leporinus steindachneri). The surface oocyte, stage and duration of embryonic/larval development were classified by using a stereoscopic microscope, and showed variations between the studied species. The transformation of the juveniles also showed variations, with 16 days post-hatching in P. hartii, 5 days in Brycon sp and 14 days in L. steindachneri. In immunohistochemistry, BMP-2 was identified in the blastocoel of the blastocyst and gastrula stages; forming the optic vesicle, notochord and somites on embryo of the ivestigated species. In larval and juvenil stages, BMP-2 has been identified in the formation of gills, eyes, heart, stomach, intestine, liver, fins, muscle and ossification in the species studies. Adults were sacrificed, dissected for biometrics measurements of the internal organs and photo documentation. The stomach of P. hartii showed a \"U\" shape with the presence of a structure similar to a gizzard, whereas in Brycon sp it was shaped like a \"J\" with the presence of pyloric caeca and in L. steindachneri it presented a \"Y\" form without the presence of pyloric caeca. Skeletons were prepared by retting technique with Dermestides beetles, interesting differences were observed between numbers of bones, where 4 infraorbital bones were found in P. hartii, 6 in Brycon sp and 4 in L. steindachneri. It is concluded that the specimens of P. hartii show ilyophagous eating habits while Brycon sp and L. steindachneri were considered omnivorous based on anatomical findings and that expression of BMP-2 is linked with morphogenesis and organogenesis of the studied species.

Orientador: Ivanira Jose Bechara / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T09:34:23Z (GMT). No. of bitstreams: 1 Bockelmann_PetraKarla_D.pdf: 29179947 bytes, checksum: 8c02cdd38976a29e54d61610a6bfd9fe (MD5) Previous issue date: 2008 / Resumo: As nadadeiras caudais de teleósteos, quando parcialmente amputadas, passam por um rápido processo de regeneração chamado de regeneração epimórfica, caracterizado pela formação de uma massa de células indiferenciadas, diferenciação dessas células, síntese e deposição de matriz extracelular e restauração morfológica. A regeneração da nadadeira é extremamente sensível a fatores físicos e químicos externos, tais como variações na temperatura, intensidade da luz, ação de alguns agentes contaminantes ambientais e ação de algumas drogas que podem interferir na capacidade regenerativa das nadadeiras dos peixes teleósteos. Existem relatos na literatura, que drogas anti-inflamatórias não esteróides, podem interferir de alguma forma na restauração tecidual de diversos organismos, uma vez que inibem a ação da enzima ciclooxigenase e, conseqüentemente, a conversão do ácido araquidônico em prostaglandina, elementos que desempenham funções importantes na proteção celular, crescimento, angiogênese e produção de matriz extracelular. Em vista disso, este trabalho teve como objetivo avaliar os efeitos de drogas antiinflamatórias não esteróides, naproxeno e indometacina, durante o processo regenerativo da nadadeira caudal de peixe teleósteo Cyprinus carpio (carpa). Para isso, foram montados experimentos com cinco grupos: grupo formado com peixes que serviram como controle, grupo formado com peixes que entraram em contato com o naproxeno, na dose de 15,6 mg/L, e três grupos formados por peixes que tiveram contato com a indometacina nas doses 10, 20 e 30 mg/L cada. Os peixes foram anestesiados e suas nadadeiras caudais foram amputadas transversalmente e, após a amputação os peixes foram divididos entre os cinco grupos e permaneceram nos aquários até que a regeneração ocorresse. Os animais foram anestesiados, sacrificados e as nadadeiras em regeneração foram excisadas e fixadas em intervalos de 1, 2, 4, 5, 6, 8, 10 e 12 dias após a amputação. As amostras foram processadas para permitir uma análise histoquímica, ultra-estrutural e morfométrica das possíveis alterações no processo regenerativo da nadadeira caudal de teleósteo em contato com as drogas em questão. Os grupos tratados com o naproxeno e a indometacina utilizada na dose de 10 mg/L apresentaram o processo de regeneração de forma semelhante ao grupo controle, ou seja, não afetaram a formação da capa epidermal, a formação do blastema, a diferenciação das células blastemais, bem como a síntese, deposição, organização e mineralização dos componentes da matriz lepidotriquial e a síntese das actinotriquias durante o processo regenerativo da nadadeira caudal. No entanto, os peixes tratados com a indometacina nas doses de 20 e 30 mg/L apresentaram um atraso no processo de regeneração da lepidotriquia e da actinotriquia quando comparados com os peixes do grupo controle. Estudos mais detalhados sobre os mecanismos de ação das drogas anti-inflamatórias não esteróides e a ação dessas drogas sob a expressão ou a inibição da expressão de alguns genes envolvidos no processo de regeneração da nadadeira caudal de teleósteo talvez possam responder a razão das diferenças de efeitos entre essas duas drogas / Abstract: The fins of teleosts, when partially amputated, they pass for a quick regenerative process called epimorphic regeneration, characterized by the formation of a mass of undifferentiated cells, by the differentiation of these cells, by the synthesis and the deposition of the extracellular matrix and morphological restoration. The regeneration of the fin is extremely sensitive to external physical and chemical factors such as temperature variations, light intensity, the action of some environmental contaminants and the action of some drugs that can interfere in the regenerative capacity of teleost fins. There are some studies that show that nonsteroids anti-inflammatory drugs can interfere somehow in the tissue restoration of many organisms, as they inhibit the action of ciclooxygenase enzyme and, consequently, the conversion of arachidonic acid in prostaglandins, elements that execute important roles in cell protection, growth, angiogenesis and in the production of extracellular matrix. In this sense, this study aimed to evaluate the effects of nonsteroid anti-inflammatory drugs, naproxen and indomethacin, during the regenerative process of the teleost tail fin Cyprinus carpio (carp). Therefore, experiments were undertaken in five groups: the control group fish, group of fish in touch with naproxen in doses of 15.6 mg/L, and three groups of fish in contact with indomethacin in doses of 10, 20 and 30 mg/L each. The fish were anesthetized and their fins transversally amputated and, after amputations the fish were divided among the five groups described above and were left in the aquaria until the occurrence of regeneration. The animals were anesthetized, sacrificed and the regenerating fins excised and fixed in intervals of 1, 2, 4, 5, 6, 8, 10 and 12 days after amputation. The samples were processed in order to permit a histochemical, ultra-structural and morphometric analysis of the possible alterations in the regenerative process of the tail fin of the teleosts in contact with the drugs mentioned above. The group treated with naproxen and indomethacin in a 10 mg/L dose showed a regenerative process similar to the control group, thus, it did not affect the formation of the epidermal layer, the formation of blastema, and the differentiation of blastemal cells, as well as its synthesis, deposition, organization and mineralization of the lepidotrichial matrix and the synthesis of actinotrichia during the process of regeneration of the tail fin. However, the fish treated with indomethacin in doses of 20 and 30 mg/L presented a delay in the regenerative process of the lepidotrichia and actinotrichia when compared to the control group fish. Detailed studies about the mechanisms of nonsteroids anti-inflammatory drugs action and the action of these drugs under the expression or inhibition of expression of some genes involved in the teleost tail fin regenerative process could explain more precisely the reason of the differences of effect between these two drugs / Doutorado / Histologia / Doutor em Biologia Celular e Estrutural

A diet study of swordfish, Xiphias gladius, was conducted in the Straits of Florida from April 2007 to December 2008. The stomachs of 131 swordfish were analyzed. Thirteen species of teleosts, three species of cephalopods, and one species of crustacean were observed in the diet. Cephalopods dominated the swordfish diet by weight (73.38%), number (69.90%), and occurrence (80.91%) and ranked highest in importance in the diet when calculating the index of relative importance (IRI). Teleosts followed by weight (25.16%), number (26.34%), occurrence (68.18%), and IRI (3,510.97). The prey species with the greatest dietary importance was Illex sp followed by unidentifiable ommastrephids. Stomach fullness index (SFI) was calculated ranging from 0 (empty stomachs) to 3.57. Additionally, correlations for juvenile male swordfish length and prey length (r²=0.647) as well as female adult swordfish weight and prey weight (r²=-0.327) were found to be significant. Overall feeding seasonality showed that swordfish primarily fed on teleosts (58%) in the spring, cephalopods (70%) in the summer, and cephalopods (75%) in the winter. When considered individually, female, male, and adult swordfish followed this pattern; however juveniles did not follow the overall feeding trend according to season. They fed regularly on cephalopods during spring (57%) and summer (61%) consuming the highest abundance of cephalopods during the winter (85%). Overall, swordfish appeared to be opportunistic feeders altering its food choices when abundance of prey may have changed or when food items were present.

<p>Recently, the focus of metal toxicity has shifted from concentrations within the aqueous environment to bioaccumulation within the organism. In this regard, the Biotic Ligand Model (BLM) relates the binding of metal at specific toxic sites (“ligands”) to eventual toxicity, whereas the Tissue Residue Approach (TRA) relates metal burdens at whole body, tissue, or subcellular levels to eventual toxicity. However, much less is currently known regarding Ni in comparison to other metals. This thesis addresses this knowledge gap by evaluating the use of Ni bioaccumulation as a predictor of toxicity in a number of fish and invertebrate species; bioaccumulation endpoints examined included Michaelis-Menten uptake parameters (K_d, B_max), a BLM parameter (log K_NIBL values) and critical body residues (CBR50 values)</p> <p>More sensitive species exhibited higher binding affinities and lower binding capacities for Ni. In invertebrates, a strong overall correlation was observed between log K_NiBL values for whole organism binding and acute toxicity to the extent that measurement of toxicity was an acceptable alternative to measurement of binding affinity, and vice versa. However, in two teleosts, the same comparison showed that a Ni BLM built on bioaccumulation would be more protective than one built on toxicity. The results further validated a central concept of the BLM - that short term metal bioaccumulation is predictive of longer term toxicity. Acute (96-h) Ni bioaccumulation predicted chronic (15 or 30-day) mortality in both salt and fresh water. In the latter, acute (96-h) sub-cellular bioaccumulations of Ni in either biologically active (BAM) or biologically inactive metal pools (BIM) of one fish species (round goby) were also predictive of 30-d mortality. However, goby were more sensitive to Ni bioaccumulation in the BAM versus BIM fraction.</p> <p>This thesis advances the use of bioaccumulation as a predictor of Ni toxicity and may have implications for metal toxicity frameworks such as the BLM and TRA.</p> / Doctor of Philosophy (PhD)

<p> The origin of terrestrial vertebrates from water-dependent fish involved numerous morphological and physiological modifications (Benton, 1990). Interest in the adaptive mechanisms involved in the transition from aquatic to terrestrial environments has led to research involving lungfish. African lungfish are obligatory air breathers and have a primitive lung and characteristically underdeveloped gills compared to freshwater teleosts. The gills are thought to play an important role in CO2 excretion and possibly in water and ionic exchange while in aquatic conditions. At present, little is known about the basic ionoregulatory physiology of lungfishes; the aim of this thesis was to describe the basic principles of ion and water balance in two species of African lungfish, Protopterus dolloi and Protopterus annectens. Patterns and rates are very similar in the two species, apart from differences in water handling at the kidney. In aquatic conditions, plasma ion (Na+, Cl-, Ca2+) levels are lower than in teleost fish. The major site of diffusive water exchange appears to be the gills. The skin is well vascularized and also serves as site of water exchange, and likely Cl- and Ca2+ uptake as well. However, water and ion exchange rates are lower than in freshwater teleosts, probably due to the reduced gill area, though glomerular filtration, urine flow rates (an index of osmotic permeability), and urinary ion excretion rates are comparable to those of teleosts. Water exchange rates increase immediately after feeding, likely associated with specific dynamic action, and decrease with prolonged terrestrialization, likely due to disturbances in gill function. A budget analysis of ion balance indicates that both unidirectional uptake from the water and net uptake from the food (especially for Cl-) are important, whereas unidirectional efflux across the gills and/or skin is a larger route of ion loss than are feces or urine. Despite many physiological differences between freshwater teleosts and the African lungfish, water and ion balance are maintained in a broadly similar fashion and are achieved by compensating for the reduced gill area by ion acquisition via the skin and by greater ion reabsorption by the kidneys.</p> / Thesis / Master of Science (MSc)

En aquest treball de tesi doctoral es descriu l'estructura gonadal, gametogènesi i cicle anual de Scorpaena porcus, S. scrofa i S. elongata per tal d'aprofundir en el coneixement dels diferents graus d'especialització dins l'oviparisme en peixos. Es pretén fer èmfasi en aquells trets inusuals que difereixen del què s'ha descrit fins ara per la majoria de les espècies ovípares de teleostis, i relacionar-los amb l'estratègia reproductiva de les espècies que els presentenEl mostreig s'ha dut a terme de forma intensiva entre l'any 2000 i 2002, tot i que s'ha continuat recol·lectant mostres fins a l'agost de 2004, amb més o menys freqüència segons la necessitat. En total s'han obtingut 258 exemplars de S. porcus, 119 de S. scrofa i 46 de S. elongata.S'ha pogut veure com S. porcus, S. scrofa i S. elongata són espècies ovípares ovulípares especialitzades, ja que la seva estructura ovàrica presenta tot una sèrie de trets molt particulars i poc comuns a la resta de peixos ovípars estudiats fins ara: posició central del raquis musculo-connectiu que es troba envoltat completament pel lumen i la paret ovàrica; presència de peduncles en oòcits en fase de creixement secundari; escassetat i mida petita dels alvèols corticals; poc gruix de la zona radiata; i secreció d'una massa gelatinosa que engloba els ous en el moment de la posta. Totes aquestes característiques també s'han observat en Scorpaena notata, suggerint que l'especialització de l'oviparisme ovulípar es dóna en tot el gènere Scorpaena.L'estructura testicular i l'espermatogènesi d'aquestes espècies també és força particular. Per una banda els testicles són del tipus lobular no-restringit, tot i que presenten algunes característiques com la ordenació parcial dels cists segons l'estadi de maduració de les cèl·lules germinals que contenen i l'absència de lumen central, que actualment només s'ha observat en testicles del tipus lobular restringit de les espècies de la sèrie Aterinomorpha. Per l'altre banda, l'espermatogènesi és del tipus semicística, és a dir, els cists s'obren abans d'acabar tot el procés i les cèl·lules germinals s'acaben de desenvolupar a la llum del lòbul fins a espermatozoides.La posta d'aquestes espècies és múltipla i constisteix en una massa gelatinosa d'ous pelàgica, que en el cas de S. porcus s'alliberen entre els mesos de juny i agost, i en S. scrofa, a partir del mes de juliol. S'ha relacionat la presència d'aquesta massa amb un aparellament mascle-femella, de manera que el mascle alliberaria l'esperma directament sobre la massa d'ous, assegurant així la fartilització total dels mateixos. / The present work describes gonadal structure, gametogenesis and annual cycle of Scorpaena porcus, S. scrofa and S. elongate, to go more deeply into the knowledge of different degree of oviparity specialization in fishes. We pretend to emphasize unusual features that diverge from those that have been described until now for oviparous teleosts.Sampling was performed intensively between years 2000 and 2002. However, collection of specimens was continued until August 2004 sporadically according to experimental needs. We obtained a total of 258 specimens of S. porcus, 119 of S. scrofa and 46 of S. elongata.S. porcus, S. scrofa and S. elongata are specialized ovuliparous species. The ovary showed many characteristics that are not typical for oviparous fishes: central ovarian stroma, pedunculate oocytes, scarcity and small size of cortical alveoli, thinness of the zona radiata, and a gelatinous matrix secreted during the maturation. All these features also were observed in Scorpaena notata suggesting that specialized ovuliparity probably occurs in the entire genus Scorpaena.Testicular structure and spermatogenesis are unusual too. On one hand, these three species have an unrestricted lobular testis. However, they present a partial arrangement of cists according to the stage of development of germinal cells, and they don't have central lumen, two features that currently have only been described for the restricted lobular testes of aterinomorph fishes. On the other hand, spermatogenesis is semicystic: cysts open before the end of spermatogenesis, which is then completed in the lobule lumen.These species are multiple spawning fishes, and they release a pelagic gelatinous mass of eggs. Spawning in S. porcus occurs between June and August, and in S. scrofa begins in July. The presence of the gelatinous mass of eggs has been related to a mating behaviour between male and female that guarantees the fertilization of the whole pond.

L’alternance de périodes glaciaires et interglaciaires durant les 20 derniers Ma a mené à des changements environnementaux répétés au niveau du plateau continental antarctique. C’est dans ce contexte que les téléostéens de la famille des Nototheniidae se sont adaptés et diversifiés à travers plusieurs vagues de radiations (dont les Trematominae), dominant l’Ichtyofaune australe. Parmi les Nototheniidae, le groupe « Trematomus » (genres Cryothenia, Pagothenia, Trematomus et Indonotothenia) est celui où l’on observe la plus grande diversité chromosomique, avec des nombres diploïdes de chromosomes allant de 24 à 58, impliquant de nombreux réarrangements ayant accompagné les spéciations. Nous avons cherché à caractériser ces remaniements chromosomiques. Avec un caryotype ancestral inféré de 2n = 48, une conservation des unités chromosomiques entre espèces, et une constance des tailles de génome, l’hypothèse de réarrangements structuraux sans polyploïdisation préalable est la plus probable. Afin de reconstruire l’histoire évolutive de ces événements, nous avons recherché les homologies chromosomiques interspécifiques. Ceci nous a permis de reconstituer les remaniements (majoritairement des fusions) que nous avons repositionnés sur la phylogénie résolue des « Trematomus ». Contrairement à ce qui a été publié pour le genre Notothenia, nos résultats suggèrent des acquisitions multiples et indépendantes. Les éléments transposables (ETs) peuvent être impliqués dans les remaniements chromosomiques par le biais de recombinaisons ectopiques. Ils participent alors à la diversification des lignées au cours de l’évolution. En raison de leur régulation épigénétique, leur mobilisation massive peut être induite en cas de variations environnementales importantes. Nous nous sommes intéressés à trois super-familles d’ETs (DIRS, Gypsy and Copia) dans ces génomes. Les DIRS1 ont montré des patrons d’insertions en points chauds dans les régions centromériques et péricentromériques. Etant donné leur mode de transposition décrit et leur propension à s’insérer dans des copies préexistantes, nous proposons un rôle des éléments DIRS1 comme facilitateurs des fusions observées lors de la diversification des « Trematomus ». / In the last 20 My, multiple glacial-interglacial cycles led to strong and repeated environmental changes on the Antarctic continental shelf. In this changing environment, nototheniid fishes diversified through several rounds of species radiation (one of which within Trematominae), and now constitute the dominant group in Antarctic teleosts. Among Nototheniidae, the group « Trematomus » (genera Cryothenia, Pagothenia, Trematomus and Indonotothenia) exhibits the highest chromosomal diversity, with diploid chromosome numbers ranging between 24 and 58, involving many rearrangements probably linked to speciation. We characterized the nature of these chromosomal repatternings. With an inferred ancestral state of 2n = 48 acrocentric chromosomes, a conserved number of chromosomal structural units, and a constancy of the genomes sizes we measured; the hypothesis of structural modifications is favored rather than a whole genome duplication associated to drastic reductions. In order to reconstruct an evolutionary scenario of such chromosomal rearrangements accompanying the trematomine diversification, we identified interspecific chromosomal homologies. This allowed us to reconstruct the rearrangements events (mostly centric and tandem fusions). We plotted them on a phylogeny we reconstructed based on our own ddRAD-seq data. Contrary to what was reported for the Notothenia, our results are in favor of independent acquisitions. Transposable elements (TEs) can lead to chromosomal rearrangements through ectopic recombination events, hinting at a role as drivers of specific-lineage diversification. Moreover, due to their epigenetic regulation, TEs can be mobilized when thermic changes occur. We focused on three retrotransposon superfamilies (DIRS, Gypsy and Copia) in nototheniid genomes. The DIRS1 showed unexpected accumulation patterns of insertion in the centromeric and pericentromeric regions. Given the mechanism of DIRS1 transposition and their tendency to sometimes insert on pre-existing copies (homing), we suggest a role of DIRS1 elements as facilitators of the fusions that occurred during the trematomine radiation.