Orientador: Alessandra Melchert / Resumo: O estudo teve por objetivo avaliar a preferência alimentar e as dietas oferecidas a tatus de nove bandas mantidos sob cuidados humanos, enfatizando a ação das dietas sobre o desempenho, avaliação clínica e metabolismo animal, assim como o aproveitamento dos nutrientes de cada dieta. Foram utilizados para a avaliação da preferência alimentar 10 tatus de nove bandas (D. novemcinctus) adultos, sendo oito machos e duas fêmeas; seis tatus de nove bandas (D. novemcinctus) adultos, sendo cinco machos e uma fêmea, para o ensaio de digestibilidade; e oito tatus de nove bandas (D. novemcinctus) adultos machos para a avaliação clínica e metabólica. Para o teste de preferência alimentar foram testadas quatro dietas que diferiram quanto ao seu teor de proteínas e inclusão de frutos em sua composição. Para o ensaio de digestibilidade e avaliação clínica e metabólica foram testadas duas dietas com ou sem inclusão de frutos em sua composição. O teste de preferência alimentar foi conduzido utilizando a observação em três pontos: frequência de consumo, ingestão alimentar e razão da ingestão. O ensaio de digestibilidade foi realizado após 70 dias de tratamento. A avaliação clínica e metabólica ocorreu antes e ao final de 90 dias de fornecimento de cada uma das dietas, sendo que 60 dias antes do fornecimento de cada dieta foi realizado um período preparatório. Durante o período preparatório os animais receberam uma dieta constituída por ração canina e carne, para que ao início dos tratamentos ap... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aims of the study was to evaluate the dietary preference and the diets offered to the nine-banded armadillos kept under human care, emphasizing the action of the diets on the animal performance, as well as the use of the nutrients of each diet. Ten adult nine-banded armadillos (D. novemcinctus) were used for the evaluation of the food preference, being eight males and two females; and six adults nine-banded armadillos (D. novemcinctus), being five males and one female, for digestibility assay. and eight males adults nine-banded armadillos (D. novemcinctus) for clinical and metabolic evaluation. Food preference test, tested four diets that differed in their protein content and fruit inclusion in their composition. For the digestibility assay and clinical and metabolic evaluation were tested two diets with or without fruit inclusion in its composition. The food preference test was conducted using three-point observation: consumption frequency, food intake and intake ratio. The digestibility assay was performed after 70 days of treatment. Clinical and metabolic evaluation occurred before and the end of 90 days of supply of each diet, and 60 days before the supply of each diet a preparatory period was performed. During the preparatory period, the animals received a diet consisting of dog food and meat, so that at the beginning of the treatments presented similar body and metabolic conditions. The diet with the highest protein inclusion, obtained the highest preference in all ... (Complete abstract click electronic access below) / Doutor

Einleitung: Wohlbefinden und Tierschutzaspekte spielen in der modernen Zootierhaltung eine entscheidende Rolle und werden von vielen Seiten diskutiert und kritisiert. Die Überwachung des Wohlbefindens ist eine Herausforderung, da nicht alle in menschlicher Obhut gehaltene Tiere leicht untersucht werden können. Probenentnahmen zur Gesundheitsüberwachung stellen zusätzlichen Stress dar. Dass Stress maßgeblich das Wohlbefinden tangiert, ist umfassend bereits beschrieben. Möglichkeiten des Einsatzes nicht invasiver Methoden bieten zoologischen Einrichtungen den Handlungsspielraum, eine Überwachung ihrer Tiere, ohne sie fangen zu müssen, möglich zu machen. Das bedeutet weniger Stress für die Tiere, weniger Gefährdungspotential für das Pflegepersonal und den Tierarzt. Im Rahmen der nicht invasiven Überwachung können bereits erste Hinweise zu weiterführenden Untersuchungen veranlassen und helfen den zoologischen Einrichtungen bei der Überwachung und Verbesserung des Wohlbefindens. Ziel der Untersuchung: Ziel war es, nicht invasive Methoden zur Beurteilung des Wohlbefindens in menschlicher Obhut gehaltener Wildtiere retrospektiv zu betrachten. Hierzu wurden Tierarten, als Wildformen und domestizierte Formen, aus fünf Säugetierordnungen, die in Zoos gehalten werden, untersucht. Evaluierte und erprobte Verfahren wurden zusammengetragen und vergleichend aufgezeigt. Dabei wurden stets der Body Condition Score, Cortisolmetabolite und Verhaltensstudien betrachtet. Wesentlich war es Parallelen und Möglichkeiten zwischen den Tierartengruppen darzustellen und die Praktikabilität der Kombination der Methoden zu betrachten. Weiterhin war es Ziel, Grenzen und Lücken aufzuzeigen und weiterführende Untersuchungen anzuregen. Material und Methoden: In einer Literaturrecherche wurden ca. 1200 Literaturstellen auf die Nutzbarkeit für nicht invasive Überwachung von Wohlbefinden und Tierschutzaspekten sondiert. Im Rahmen der Fokussierung und Eingrenzung wurden fünf Säugetierordnungen mit ausgewählten Familien betrachtet, dafür wurde ein Suchkatalog angelegt. Dieser wurde in den Datenbanken Pub Med, Web of Sciene und dem Leibniz Institut für Zoo und Wildtierforschung recherchiert. Ergebnisse: Rüsseltiere (Proboscidea), Herrentiere (Primates), Raubtiere (Carnivora), Unpaarhufer (Perissodytyla) und Paarhufer (Artiodactyla) mit weit über 60 Vertretern wurden betrachtet. Um eine Vereinheitlichung zur Bewertung des Wohlbefindens bei genannten Wildtieren aufzustellen habe ich das BBC-Schema (Body Condition Score, Behavior und Cortisolmetabolite) entworfen. Somit können bei den Proboscidea alle Bereiche der BBC angewendet werden. Hingegen bei den Primates scheinen besonders Cortisolmetabolite und Verhaltensanalysen zielführend zu sein. Bei den Carnivora bieten BBC-Betrachtungen gute Ansätze, jedoch bedarf es weiterer Body Condition Score Erweiterungen für kleinere Vertreter. Bei den Perissodytyla sind BBC in allen Bereichen anwendbar, jedoch sind bisher für die Tapiridae keine Ethogramme zur Verhaltensevaluierung beschrieben. Für Artiodactyla ist das BBC-Schema eine gute Möglichkeit zur Beurteilung von Wohlbefinden und Stress. Der Unterbereich der Bovidae bedarf bei vielen Vertretern weiterer Evaluierungen von Cortisolmetaboliten und Verhaltensaufnahmen. Mit dem BBC-Schema konnte für jede Gruppe eine geeignete Kombination zur nicht invasiven Beurteilung von Wohlbefinden und Tierschutzaspekten aufgezeigt werden. Darüber hinaus war es möglich tierartübergreifende Parallelen, Unterschiede, Lücken, als auch Vor- und Nachteile herauszuarbeiten. Schlussfolgerung: Die Untersuchungen zeigen, dass eine einzelne Methode nicht immer eine absolute Aussagekraft hat. Desto wichtiger ist eine tierartspezifische, nach Fragestellung und Untersuchungsmöglichkeiten angepasste Auswahl zu nutzen. Anhand meiner betrachteten Methoden lassen sich die ,,5 Domains“ (Ernährung, Umwelt, Gesundheit, Verhalten, und geistige Gesundheit) mit den nachfolgend genannten Methoden als Bestandteil des BBC Schemas überwachen und beurteilen. Body Condition Scores bieten die Möglichkeit zur langfristigen Überwachung des Ernährungszustandes. Verringerungen oder Steigerungen des BCS, können Ausdruck von Faktoren, die das Wohlbefinden beeinflussen, sein. Ausgewählte Verhaltensweisen (Behavior) sind pathognomonisch für mangelndes Wohlbefinden und lassen sich mit Verhaltensaufnahmen beurteilen und quantifizieren. Analysen helfen, Verbesserungen nach Anpassungen der Haltungsbedingungen und/oder Elimination eines Stressors aufzuzeigen. Ebenfalls kann abnormales Verhalten Hinweise auf Erkrankungen geben. Das Stresshormon Cortisol, welches bei Stress vermehrt ausgeschieden wird, kann kurzfristig in Speichel und Harn, mittelfristig im Kot und langfristig in den Haaren nachgewiesen werden. Es kann Rückschlüsse auf die Stressoren, Erkrankungen oder mangelndes Wohlbefinden im Allgemeinen geben.:Inhaltsverzeichnis: 1. Einleitung 1 2. Literaturübersicht 2 2.1 Tierschutzaspekte, Wohlbefinden und die ,,Five Domains“ 2 2.2 Nicht-invasive Methoden zur Beurteilung von Wohlbefinden und Stress 5 a) Body Condition Score: 5 b) Cortisolmetabolitebestimmung aus Kot, Harn, Speichel und Haaren: 5 c) Verhaltensanalysen: 8 3. Material 11 4. Methoden 11 5. Ergebnisse 14 5.1 Elefanten (Elphantidae) 14 5.2 Herrentiere (Primates) 19 5.2.1 Menschenaffen (Hominidae) 19 5.2.2 Krallenaffen & Totenkopfaffen (Cebidae) 24 5.2.3 Paviane & Rhesusaffen (Cercopithecidae) 27 5.3 Raubtiere (Carnivora) 32 5.3.1 Felidae: Großkatzen (Pantherinae) und Kleinkatzen (Felinae) 32 5.3.2 Hyänen (Hyaenidae) 39 5.3.3 Hunde (Canidae) 40 5.3.4 Bären (Ursidae) 45 5.4 Unpaarhufer (Perissodytyla) 51 5.4.1 Pferde (Equidae) 51 5.4.2 Tapire (Tapiridae) 55 5.4.3 Nashörner (Rhinocerotidae) 59 5.5 Paarhufer (Artiodactyla) 63 5.5.1 Schweine (Suidae) und Pekaris (Tayassuidae) 63 5.5.2 Hirsche (Cervidae) 70 5.5.3 Hornträger (Bovidae) 75 5.5.4 Giraffen und Okapis (Giraffidae). 81 6. Diskussion 84 7. Zusammenfassung 91 8. Summary 93 9. Literatur 95 10. Danksagung 123

A novel clinical assay for the assessment and subsequent treatment of Haemonchus infection in sheep to slow down the development of anthelmintic resistance – the FAMACHA / Dissertation (MSc)--University of Pretoria, 2001. / Veterinary Tropical Diseases / unrestricted

Populations of many European bird species have decreased in recent years. Of seabird species, roughly 25 % are classified as threatened or as species of future concern. In the Baltic Sea, an entire ecosystem faces the aftermath of anthropogenic changes, which might be one of the reasons behind the decreasing population of Caspian terns (Hydroprogne caspia). In this paper, an attempt was made to shed light upon nestling survival in Caspian terns in breeding colonies on islets outside of Gotland, Sweden, by using bird ringing data as well as re-sightings of post-fledged terns. Based upon literature from other species, I expected a higher survival probability with earliness of breeding time, and improved survival probability with higher nestling body condition. Significant study results showed that re-sighted Caspian terns had slightly earlier hatching day (150 ± 6.55) compared to never-again seen Caspian terns (153 ± 8.08), implying that early breeding time might be of benefit in the species. However, no significant result could confirm that high body condition in nestling terns was correlated with general survival probability, indicating that a myriad of other factors is likely at play. / Många fågelarter har under de senaste åren minskat drastiskt i Europa. Inom gruppen havsfåglar har konstaterats att omkring 25 % av alla arter tilldelats hotstatus eller bedömts vara av framtida mål för bevarande. I Östersjön hotas idag ett helt ekosystem av de effekter som genererats genom antropogena processer. Av populationer som påverkats i området med en kritisk tillbakagång under 2000-talet, inräknas den kolonihäckande arten skräntärna (Hydroprogne caspia). I denna studie användes ringmärkningsdata och återfyndsinformation från gotländska skräntärnor, i syfte att undersöka artens generella överlevnadschans i relation till födelseperiod och kroppskondition som ungfågel. Till resultatet förväntades att ungar födda tidigt under säsongen hade högre överlevnadschans än ungar födda sent.  En längre livslängd i dagar antogs höra ihop med högre kroppskondition hos ungfåglar på häckplatsen. Mitt resultat visade med signifikans att återsedda tärnor från Gotland hade lite tidigare födelsedatum i genomsnitt (dag 150 ± 6.55) än ej återsedda skräntärnor (dag 153 ± 8.08). Samband mellan tärnornas överlevnad och kroppskondition kunde ej påvisas, vilket indikerar att en mängd andra faktorer med all förmodan inverkar på skräntärnors överlevnadschanser.

<p> Per- and polyfluoroalkyl substances (PFAS) are a class of persistent environmental contaminants that have become ubiquitous, resulting in widespread exposure among humans and wildlife. Amphibians are regularly exposed in the field, making them susceptible to sublethal effects of PFAS exposure. In amphibians exposed to PFAS, deleterious effects have been observed, including reduction in body condition measured using the scaled mass index (SMI) and degraded hepatic condition, among others. PFAS may dysregulate lipid metabolism by altering signaling cascades regulated by peroxisome proliferator activated receptors (PPAR), but whether changes in energy stores can explain changes in amphibian SMI and/or hepatic condition remain underexplored. Since lipids are a critical energy reserve for anurans, understanding whether lipid metabolism is being perturbed is critical. The central objective of this thesis was to investigate the effect of PFAS on lipid homeostasis in <em>Xenopus laevis </em>tadpoles within the context of a PPAR mechanism of action (MOA), considering apical, molecular, and lipidomic endpoints. I conducted three studies: (a) a study to characterize SMI and the relative expression of the hepatic xPPARα/β/γ during metamorphosis, (b) a pharmaceutical exposure to assess the <em>in vivo</em> effects of xPPARα/β/γ agonism on hepatic gene expression for select downstream targets (<em>apoa5, fabp1, acox1,​ pck1</em>), and (c) a chronic PFAS exposure to investigate the effects of environmentally relevant concentrations (PFOS, PFHxS, PFOA, PFHxA at 0.5 ppb; binary mixture of PFOS:PFHxS at 1 ppb) on lipid homeostasis through apical endpoints (mass, snout vent length, SMI, hepatic condition), relative hepatic gene expression, and Multiple Reaction Monitoring (MRM) profiling of the hepatic lipidome for changes in relative class abundance. In study (a), I identified SMI and hepatic expression of <em>xPPARα/β/γ</em> is dynamic during late metamorphosis, indicating the potential for heightened susceptibility. However, in study (b), pharmaceutical agonists had no effect on <em>X. laevis</em> at high doses. For study (c), I did not observe effects on a majority of apical endpoints, including SMI, but detected a significant sex-specific reduction in hepatic condition for male<em> X. laevis</em> tadpoles exposed to single-chemical perfluorosulfonic acid (PFSA) treatments. For gene expression, I observed a transient downregulation for apolipoprotein-V (<em>apoa5</em>) at Nieuwkoop and Faber (NF) stage 62 for <em>X. laevis</em> tadpoles exposed to single-chemical perfluorocarboxylic acid (PFCA) treatments. Lipid profiling detected transient dysregulation of predominantly membrane lipids in-response to short-chain PFAS treatments at NF 58. Overall, our findings indicate PFAS may exert toxicity during anuran metamorphosis through multiple mechanisms of action (MOA) with sex-specific and developmental-stage specific outcomes.</p>

No description available.

Thesis ( (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2019 / A lack of energy and water in livestock production limit the performance of the animal. Therefore, the objective of this study was to determine the effect of spineless cactus as a source of energy and water on feed intake, feed digestibility and milk production of Holstein cows. Cactus serves as fresh forage or stored as silage for later feeding in livestock. However, there is limited information about cactus nutrients, their proportions in different species and the variability of these proportions with season. A total of four multiparous lactating Holstein cows with an average of 650 ± 80kg live weight were used and assigned to four dietary treatments with four replicates. Each animal was used four times. A cross-over design was used. The four dietary treatments were 0%, 4%, 8% and 12% of spineless cactus meal inclusion levels. The study period was 21 days of adaptation period and 6 days of collection period. Higher digestibility and energy supply (P<0.05) were observed with spineless forage diets compared to the control diet. Inclusion of spineless in the diets improved (P<0.05) diet intake and milk production in Holstein cows. However, an improved performance in milk production was observed with spineless cactus meal inclusion levels of 4%, 8% and 12%. Amongst the diets, 0% inclusion level had lower dry matter intake of 22.7kg (P<0.05) compared to those which had spineless cactus meal. High dry matter intake resulted in higher (P<0.05) milk production of 22.7, 24.7, 23.4 and 23.8 litres for 0, 4, 8 and 12% spineless cactus meal inclusion levels, respectively. However, cows on 4% inclusion level had higher milk yield than the other diets. Milk quality (butter fat, protein, lactose, somatic cell count and milk nitrogen urea) of Holstein cows was not (P>0.05) affected by the level of spineless cactus meal inclusion in the diet. Dry matter intake, neutral detergent fibre intake, acid detergent fibre intake and metabolisble energy intake of the cows were optimized at different spineless cactus meal inclusion levels of 19.427% (r2 = 0.992), 16.375% (r2 = 0.974), 14.0% (r2 = 0.984) and 22.909% (r2 = 0.994), respectively. Spineless cactus meal inclusion had no effect (P>0.05) on ADF intake and crude protein intake. Apparent digestibility values (0.73, 0.76 and 0.76) were not significantly different at 4%, 8% and 12% of spineless cactus meal inclusion levels, respectively. v It is concluded that spineless cactus meal inclusion level in the diet affected (P<0.05) diet intake and milk production of the Holstein cows. However, these variables were optimized at different spineless cactus meal inclusion levels. It could be recommended that spineless cactus can fit perfectly in livestock rations with attention given to their low crude protein content. These opuntia species can be fed to livestock mainly cattle and sheep during any season but are needed the most during drought as supplements when forages are scarce or expensive to feed. It is, therefore, concluded that 8% of spineless cactus inclusion level can be used to maintain productivity of the animals. / National Research Foundation (NRF)

L’évaluation de la condition corporelle des carcasses des bélugas du Saint-Laurent contribue au diagnostic de cause de mortalité du pathologiste. La méthode actuelle repose sur une évaluation visuelle subjective. Notre projet visait à chercher un outil objectif d’évaluation de la condition corporelle. L’indice de masse mise à l’échelle (M̂ i) est objectif puisqu’il est calculé à partir de la masse et de la taille de chaque individu. M̂ i doit être calculé avec des constantes différentes pour les bélugas mesurant plus ou moins de 290 cm. Il produit des résultats en accord avec l’évaluation visuelle. Comme il est parfois logistiquement impossible de peser un béluga, nous avons évalué des indices basés sur d’autres mesures morphométriques. Les indices basés sur la circonférence à hauteur de l’anus pour les bélugas de moins de 290 cm et la circonférence maximale pour ceux de plus de 290 cm représentent des indices de condition corporelle alternatifs intéressants. / Evaluation of the body condition of beluga carcasses from the Estuary of the St. Lawrence contributes to the diagnosis of the cause of death by the pathologist. The current method relies on a subjective visual evaluation. Our project aimed at developing an objective tool for the evaluation of body condition. The Scaled Mass Index (M̂ i) is an objective figure since it is obtained from individual masses and lengths. M̂ i has to be calculated with different constants for belugas under and above a length of 290 cm. M̂ i yielded results consistent with visual evaluation. Since weighing belugas can be logistically impossible, we evaluated indices based on several other morphometric measurements. Indices based on girth at the level of the anus and maximal girth for animals under and above 290 cm, respectively, were deemed useful as alternative body condition indices.

Made available in DSpace on 2016-06-02T19:26:21Z (GMT). No. of bitstreams: 1 PERESSIN_Alexandre_2013.pdf: 3061472 bytes, checksum: c6d89398da14de75e2b51d1412049dd6 (MD5) Previous issue date: 2013-04-05 / Universidade Federal de Minas Gerais / Aquatic ecosystems have suffered strong anthropogenic pressure, through the construction of dams, water exploitation, chemical pollution, destruction of the surrounding environment, especially riparian vegetation, and structural changes such as channeling and siltation. Fish assemblages may respond in different ways to these environmental changes, because species exhibit different constraints, e.g., habitat demands, physiological tolerance. Thus, some species may be favored in detriment of others. Aware of the need to understand and identify the patterns response of fish assemblages and individual organisms to impact factors, this study aimed to investigate how fish biodiversity (i.e., assemblages and population-scale) respond to urbanization. Fish samples were collected in four stretches located in urban areas and six located in non-urban areas of the upper Paranapanema river basin. Chapter I focused on detecting changes in physical habitat variables, structure and composition of the fish assemblage. Multivariate analyses ordered stretches in a urbanized non urbanized gradient. Non urbanized stretches exhibited greater values of shading, vegetated surronding and coarser substrate. Assemblage structure, i.e., Shannon diversity index, Pielou evenness and Margalef richness, did not change in response to urbanization, as well as the relationship between abundance and biomass. In contrast, assemblages composition was different, as well as richness estimates based on rare species, which was lower in urban stretches. The patterns herein obtained illustrate the process of species replacement, already demonstrated in disturbed environments, in which species pre-adapted to the new conditions increase in abundance, while otherspreviously absent establish successfully. Therefore, diversity values maintain, but composition varies. In general, midwater omnivorous species were more abundant in urban areas, while loricarids and benthic invertivores presented higher average abundance in nonurban stretches. Chapter II aimed to identify changes in the trophic structure, substrate composition and its influence on trophic structure and body condition. For this, species diet was quantified according to the Degree of Food Preference (DFP) method, based on six items: plant material, algae, detritus, invertebrates, insects and fish. According to the items consumed, species were classified in trophic groups. Fourteen species were considered invertivorous/detritivorous, seven herbivorous/detritivorous, seven omnivorous and one piscivorous. Four invertivores/insectivores were exclusive of nonurban stretches and one species exclusive of urban stretches. Three herbivores/detritivores were exclusive of the nonurban stretches, whereas three omnivores were exclusive to urban stretches. Trophic structure richness, abundance and biomass were compared between urban and nonurban stretches. Abundance was not affected by urbanization, whereas richness and biomass varied between stretch groups. Substrate composition differed according to stretch type, and was positively related to invertivores/insectivores and herbivore/detritivores richness, whereas negatively related to omnivore biomass. These results suggest complex relationships between food availability, trophic plasticity and species foraging habits. It is known that coarser substrates such as rocks, branches and trunks are useful as surface for periphyton algae growth as well as shelters for aquatic macroinvertebrates. Thus, changes in substrate may alter resources availability for certain species. Omnivores, in turn, can find other sources of food items due to its trophic plasticity. In general, almost all species absent from urban stretches exhibit some trophic specialization and often depend on heterogeneous substrate for foraging. Moreover, species exclusive to urban stretches are mid-water foragers that do not depend on substrate and present high trophic plasticity. Our conclusions were supported by Astyanax fasciatus body condition analysis, an omnivorous nektonic species which demonstrated higher mean weight in urban stretches, when discounted length. / Ecossistemas aquáticos têm sofrido forte pressão antropogênica, que se manifesta na construção de barragens, captação de água, poluição química, destruição do ambiente de entorno, principalmente mata ripária, e alterações estruturais como canalizações e aporte de sedimentos. A assembleia de peixes pode responder de diversas formas a estas alterações ambientais, dado que as espécies possuem diferentes exigências fisiológicas e de habitats. Com isso, algumas espécies podem ser eliminadas e outras favorecidas. Cientes da necessidade de compreender e identificar o padrão das respostas da assembleia e organismos aos vetores de impacto, neste trabalho buscamos investigar como a ictiofauna responde à urbanização. Para isso, os peixes foram coletados em quatro trechos localizados em áreas urbanas e cinco localizados em áreas não urbanas, sempre em riachos da parte superior da bacia do alto rio Paranapanema. O capítulo I buscou detectar alterações nas variáveis físicas do hábitat, na estrutura e na composição da assembléia de peixes. Utilizando as variáveis ambientais, os trechos foram ordenados no sentido urbanizado-não urbanizado, sendo que estes últimos apresentaram valores maiores de sombreamento, área, substrato e vegetação de entorno. Verificamos que a estrutura da assembleia, representada pelos índices de diversidade de Shannon, equabilidade de Pielou e riqueza de Margalef, não sofreu alterações em resposta à urbanização, bem como a relação entre abundância e biomassa. No entanto, a composição da assembleia foi diferente e a riqueza estimada com base nas espécies raras foi menor nos trechos urbanos. Simultaneamente, a variação nos componentes ambientais explicou a variação na composição da assembleia. Estes resultados evidenciam um processo de substituição de espécies descrito para ambientes alterados, no qual espécies pré-adaptadas às novas condições aumentam em abundância e outras antes ausentes se estabelecem. Assim, a diversidade é mantida, porém, alterando a composição. Em geral, espécie onívoras forrageadoras de meia água foram mais abundantes em áreas urbanas, ao passo que loricarídeos e invertívoros bentônicos apresentaram maior abundancia média em trechos não urbanos. No Capítulo II, o objetivo foi identificar alterações na estrutura trófica, composição do substratro, influência deste na estrutura trófica e condição corporal. Para isso, a dieta das espécies foi quantificada de acordo com o método do Grau de Preferência Alimentar (GPA) para seis itens: material vegetal, algas, detrito, invertebrados, insetos e peixe. De acordo com os itens consumidos, as espécies foram classificadas em categorias tróficas. Quatorze espécies foram consideradas invertivoras/detritívoras, sete herbívoras/detritívoras, sete onívoras e uma piscívora. Quatro espécies de invertívoros/insetívoros foram exclusivas de trechos não urbanos e uma dos urbanos. Três espécies herbívoras/detritívoras foram exclusivas de riachos do tipo não urbano, o inverso dos onívoros, com 3 espécies exclusivas de riachos do tipo urbano. A partir da classificação trófica, os trechos urbanos e não urbanos foram comparados quanto à estrutura trófica em relação à riqueza, abundância e biomassa. A abundância não foi alterada pela urbanização, no entanto a riqueza e a biomassa diferiram entre os tipos de riacho. A composição do substrato, que foi diferente entre os tipos de riacho, esteve positivamente relacionada com a riqueza de invertívoros/insetívoros, de herbívoros/detritívoros e negativamente relacionada com a biomassa de onívoros. Estes resultados ilustram um processo intrincado de relações entre a disponibilidade de alimentos, plasticidade trófica e hábitos de forrageamento das espécies. Sabe-se que substratos como rochas, galhos e troncos são úteis como superfície de crescimento de algas do perifíton e também como abrigos para macroinvertebrados aquáticos. Desse modo, alterações na composição do substrato podem modificar a disponibilidade de recursos para determinadas espécies, dependentes de algas e invertebrados aquáticos, especialmente insetos imaturos. Os onívoros, por sua vez, podem encontrar outras fontes de recurso devido a sua conhecida plasticidade trófica. De maneira geral, praticamente todas as espécies ausentes dos trechos urbanos possuem alguma especialização trófica e costumam ser dependentes do substrato para o forrageamento. Por outro lado, as espécies que ocorreram apenas nos trechos urbanos são forrageadoras de meia água, não depedentes do substrato e com alta plasticidade na dieta. Esta conclusão foi amparada pela análise da condição corporal de Astyanax fasciatus, um onívoro nectônico que, quando teve descontado o comprimento do corpo, apresentou maior peso médio nos trechos urbanos.

No description available.