Orientador: Antonio Carlos Busoli / Banca: Arlindo Leal Boiça Junior / Banca: Marcos Doniseti Michelotto / Resumo: O objetivo do trabalho foi gerar informações sobre alguns parâmetros biológicos de Chrysomya megacephala sob diferentes situações, como tipos de dietas, densidades larvais e quantidades de dietas. Foi adotado um delineamento fatorial de 4x3x3 (4 tipos de dietas, 3 densidades larvais e 3 quantidades de dietas). Estas informações são importantes para o planejamento da produção comercial de larvas, como alternativa na alimentação de peixes, rãs e pássaros. O incremento da porcentagem de farelo de arroz nos tipos de dietas prolongou a duração do período larval, além da diminuição na viabilidade larval e no peso total médio de larvas. No parâmetro densidade larval, a duração do período larval foi relativamente estável, a maior viabilidade larval foi atingida pela densidade de 5 larvas/g de dieta e o maior peso total médio de larvas foi obtido na densidade de 10 larvas/g de dieta. O incremento das quantidades de dietas provoca estabilização da duração do período larval e da viabilidade larval, além da diminuição constante do peso total médio de larvas. Na análise de interação de fatores, os parâmetros biológicos estudados apresentam a mesma tendência encontrada nos tipos de dietas indicando diminuição da duração do período larval e peso total médio de larval com aumento da viabilidade larval conforme incrementam as densidades larvais e quantidades de dietas. No geral, os parâmetros biológicos estudados são afetados pelo incremento da porcentagem de farelo de arroz na dietas mesmo nas diferentes densidades larvais e quantidades de dietas. / Abstract: The objective was to get information about larval period, larval viability and total weight of larvae rearing on different situations, such as diet, larval densities and quantities of diet. Foi adotado um delineamento fatorial de 4x3x3 (4 tipos de dietas, 3 densidades larvais e 3 quantidades de dietas). It was used a factorial design 4x3x3 (4 diets, 3 larval densities and 3 quantities of diets). These information are important in the planning of larval production, as alternative food of animals, like fish, frogs and birds. The increase of percentage of rice ban increased the duration of larval period, and decreased the larval viability and the average total weight of larvae. In the larval densities, the duration of larval period was stable; the major viability was reached in the larval density of 5 larvae/g of diet and the major average total weight of larvae was in 10 larvae/g of diet. The increase in the quantity of diet, promoted stabilization in the duration of larval period and larval viability, and the constant decrease of the average total weight of larvae. In the analyses of factorial interaction, the biological parameters in study showed the same trend found in the diets suggesting decrease of the duration of larval period and average total weight with increase of larval viability when increase the larval densities and quantities of diets. In general, the biological parameters are affected for the increase in the percentage of rice ban in the diets, even in different larval densities and quantities of diets. / Mestre

Orientador: Teresa Cristina Goulart de Oliveira Sequeira / Resumo: O presente trabalho foi desenvolvido com o objetivo de caracterizar os produtos de excreção/secreção (PE/S) de larvas de Dermatobia hominis, especialmente, no que se refere à atividade proteolítica desses produtos. Os PE/S foram obtidos de larvas de primeiro estágio (L1) cultivadas em laboratório e de larvas de segundo (L2) e terceiro (L3) estágios colhidas de bovinos parasitados. O perfil das proteínas foi obtido pela eletroforese dos PE/S em gel de poliacrilamida contendo sódio dodecil sulfato (SDS-PAGE) e a atividade proteolítica foi investigada utilizando gelatina, azocaseína e N-a-benzoil-arginina-nitroanilida (BAPNA) como substratos. Para caracterização das proteases foram realizados ensaios utilizando estes mesmos substratos, nos quais as amostras foram tratadas com os inibidores: PMSF, TPCK, TLCK, DCI, E-64, EDTA, Elastatinal, Leupeptina, Fenantrolina e Antipaína. Nos PE/S de L1 foram detectadas exclusivamente proteases com peso molecular aparente acima de 168 kDa, cuja inibição revelou pertencerem aos grupos das metalo-proteases e serina-proteases. Os zimogramas dos PE/S de L2 e L3 em géis copolimerizados com gelatina revelaram uma ampla faixa de atividade proteolítica, na qual estavam presentes proteases de alto, médio e baixo pesos moleculares aparentes. Nos ensaios realizados com inibidores de proteases, utilizando os três substratos, as proteases presentes em L2 e L3 foram identificadas como pertencentes ao grupo das serina-proteases, sendo em L3, predominantemente, do tipo tripsina. As alterações nos padrões de proteólise e nas características bioquímicas das proteases presentes nos três estágios larvais discuti- se à atividade das larvas em cada fase do seu desenvolvimento. / Abstract: In the present investigation the biochemical characteristics of the Dermatobia hominis larvae secretory/excretory products (PE/S) were analyzed mainly regard to their proteolytic activities. The PE/S of first-instar larvae were collected from larvae reared in the laboratory and of the second and third instars from larvae removed from infested cattle.The PE/S were tested in a sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to identify their proteic profiles and the proteases activity were investigated using gelatine, azocasein, and N-a-benzoil-arginine-nitroanilide (BAPNA) as substrates. The proteases characterizations were performed by treating PE/S samples by the following proteases inhibitors: PMSF, TPCK, DCI, E-64, EDTA, Elastatinal, Leupeptine, Phenatroline, and Antipain. SDS-PAGE-Gelatin profiles of L1 PE/S revealed only proteases with molecular weight above 168 KDa whereas profiles from L2 and L3 PE/S revealed a high range of proteolytic activity, including high, medium and low molecular weight proteases. The assays performed with the protease inhibitors, and gelatin and azocasein as substrates, revealed that metalloprotease is the major class of proteases present in the PE/S of L1 besides the low content of serine-proteases. The major class of proteases present in the PE/S of L2 and L3 was characterized as serine-proteases, being in L3 predominantly of trypsin type. The changes in the proteolytic patterns and biochemical characteristics of the proteases found in all three instar larvae of D. hominis were with the larval activity in each phase of their development. / Mestre

The installation of marine renewable energy devices (MREDs) is progressing rapidly along many coastlines. It has been suggested that MRED arrays could provide stepping-stones for larval dispersal, mediating species range expansions or invasions. As common members of hard-substrate fouling communities and likely colonisers of MREDs, the larval dispersal processes of barnacles (Cirripedia: Thoracia) in the Firth of Lorn (Scotland) are assessed at scales ranging from mm to 10s – 100s km. At the scale of the organism itself, significant differences in larval mass densities and sinking velocities were observed between species of cirripedes, suggesting that larval physiology and morphology play an important role in water column vertical positioning. The importance of vertical positioning to horizontal transport and dispersal of larvae was identified in field surveys of the horizontal and vertical distributions of cirripede larvae, which revealed the interplay of wind-driven and tidally-oscillating currents in determining transport distances. Numerical simulations of larval dispersal based on a threedimensional hydrodynamic model then demonstrated that larvae with shallower abundance distributions often experienced greater horizontal transport, but that net dispersal distances were often greater for larvae deeper in the water column. Overall, simulated transport and dispersal distances were greatest for particles released at habitats further from the coast, such as MREDs, suggesting that the connectivity of these adult populations may be enhanced. Together, larval morphology, vertical positioning, and the coastal proximity of adult habitat could serve as useful indicators of larvae capable of reaching nearby newly installed offshore structures. For locations designated for MRED development in the Firth of Lorn, it is suggested that species with dispersal abilities similar to the cirripedes in this study could feasibly use these structures as stepping-stones for dispersal and range expansion, which could have important consequences when fouling communities are comprised of commercially important or invasive species.

The overall aim of this study was to gain a better understanding of the feeding mechanisms of the larvae and early juveniles of the sole, Dagetichthys marginatus (Soleidae), with which to assess the suitability of current feeding protocols and to facilitate the development of an appropriate pelleted feed. This was achieved by examining the ontogeny of the cranium of laboratory reared sole, with particular emphasis on those elements associated with feeding and by comparing the cranium of juvenile fish with that of adult fish. At 4 dah (days after hatch) Dagetichthys marginatus larvae develop the first rudimentary branchial arches that facilitates the capture and ingestion of food items. Subsequent development of cranial structures, such as the oral jaws, suspensorium, neurocranium, hyoid and branchial arches and the opercular apparatus enables the larvae, at 16 dah, to switch from ram feeding to suction feeding on live prey. The use of live Artemia nauplii from 4 to 16 dah is therefore appropriate. The first morphological asymmetries developed at 16 dah in the dentaries and at 22 dah the maxillae and the premaxillae began to show asymmetries. Teeth were present only on the blind side of the oral jaw elements and during this period (16 to 22 dah) the existing elements began to ossify. From 16 to 35 dah the standard feeding protocol consists of a combination of pelagic (Artemia metanauplii) and benthic prey (dead, frozen Artemia nauplii) and from 25 dah onwards a sinking pellet is provided. The time (dah) at which frozen Artemia and sinking pellets were provided, appropriately corresponded to the initiation of benthic feeding behaviour. However at this stage the use of pelagic Artemia metanauplii is inappropriate and unnecessary. At 31 dah the cranial morphology resembled that of adult fish. Adult D. marginatus display extreme asymmetries among the elements of the oral jaws, the suspensorium and certain elements of the neurocranium. Elements on the blind side are larger and more robust than those on the ocular side and are adapted for feeding, while those on the ocular side appear to have a respiratory function. From 31 dah the cranial elements are identical to those of adult fish, suggesting that no further feeding behavioural changes occurred and that a sinking pellet, of which the nutrient composition meets the requirements of the fish, would be appropriate for ongrowing.

The primary objective of this study was to examine environmental parameters thought to affect cannibalism in certain fish species. It was found that environmental, behavioural, genetic and physiological factors all affect cannibalism in the species exhibiting the phenomenon. The diversity of factors nfluencing cannibalism served to illustrate the complexity of this behaviour pattern. Feeding to satiation was found to suppress cannibalism in catfish, trout and koi carp. High population densities were found to increase the rate of cannibalism, thereby acting as a population regulation mechanism for catfish, trout and the common and koi carps. Live food, as compared with dry pelletized feed was found to significantly suppress cannibalistic aggression. Catfish grown in total darkness, provided with refuges and living in turbid conditions were found to exhibit lowered cannibalistic and territorial aggression. Various lines of evidence suggested that cannibalism has a genetic basis, as was shown by the differences in cannibalistic behaviour of the two strains of Cyprinus carpio, viz. common and koi carp, with cannibalism being higher in the latter. This finding substantiates the hypothesis that cannibalism is genetically controlled and therefore open to evolutionary change. It is concluded that cannibalism is adaptive in times of food limitation, but that it is merely a by-product of normal feeding behaviour when food is abundant. Since cannibalism is advantageous and thus adaptive, the question arises ai to whether selection is occurring at the individual or the population level (or both). It was concluded that it is acting at the individual level, and that any benefits accruing at the population level iv were simply the effect of the initial cause, viz. individual selection. One of the aims of this study was to determine whether cannibalistic tendencies in fish are influenced by differing life history style trajectories. Based on the results of this study it is hypothesized that cannibalism is an r-selected trait. wi th the understanding gained from the knowl edge of the fundamental principles governing cannibalism, certain recommendations for its control in fish culture could be made. It is, however, imperative that further intensive studies be carried out to understand more fully this complex subject. General "rules" for regulating cannibalism could be helpful for any given cannibalistic species. However, in considering the differing life-history styles of each species, it becomes evident that species-specific guidelines need to be worked out. Until then, any suggestions for cannibalistic control offered to the aquaculturist can only serve as unrefined tools.

Taxonomic studies involving only adult forms of organisms may not necessarily provide complete information about differentiation of species or about the evolutionary relationships between species grouped in higher taxa. The taxonomic importance of embryonic or larval morphology has been limited only by the lack of detailed comparative morphological work on development. Fretter (1967) has shown that larval shell characteristics are reliable for taxonomic identification of some British prosobranchs. Ostergaard (1950) proposed using the structure of egg masses, larval shell type and developmental characteristics to confirm adult taxonomic position. In recent literature reviews of the larval biology of opisthobranch, it has become apparent that a considerable amount of plasticity occurs with respect to patterns for development. Often, closely related species have radically different developmental types. Even different populations of a single species may exhibit different development. Often the ecology of the adults of closely related species is also different. However, it is not possible to make meaningful correlations between the biology of the adults and the larvae unless additional ecological and developmental information is available. There is a clear need for studies of larval development and the ways in which larval characteristics and embryology are correlated with adult biology in marine organisms. Aspects of the larval development and adult ecology of Phyllaplysia taylori Dall, are reported in this study.

The objectives of this study are to identify the larval forms of the two species of smelt, Spirinchus thaleichthys and Hypomesus transpacificus transpacificus, and to better describe their spawning times in the Sacramento-San Joaquin Estuary.

Two genera, Pachyceles and Petrolisthes, and five species of the Porcellaniae occur on the California coast north of San Francisco. Of the five species only one has had its larval development described (Pachycheleas rudis). The purpose of the present study is to describe the remaining four species and to provide a key to the species level for the larvae of northern California Porcellanidae.

In 1910 C. W. Stiles made the following comment as a part of a summary statement to his extensive study of the stigmatal plates of Dermaeentor ticks: "The specific determination of ticks is attended in many cases with con-siderable difficulty."

No description available.