No description available.

The American cockroach, Periplaneta americana, is an abundant and globally distributed species. Much of its success is attributed to its remarkable ability to alter rates and utilization efficiencies of behavioural and physiological processes so as to maintain growth and reproduction within nutritionally variable environments. This study utilized artificial diets diluted with cellulose to investigate the impact of food quality on the life history tactics of this species and the compensatory mechanisms involved in offsetting these impacts. To investigate the impact of diet quality on the life history tactics of the American cockroach, seven dietary regimes were implemented. The control condition consisted of an unaltered 100% quality diet. The remaining six treatments were diluted with cellulose resulting in diet qualities of 50%, 25%, 10%, 5%, 2.5%, and 0%. The parameters examined included mortality, longevity, instar number, instar durations, growth, maturation dates, maturation sizes, dry mass budgets, and reproduction. The dry mass budgets involved observations of growth rate, feeding rate, assimilation rate, respiration rate, assimilation efficiency, efficiency of conversion of ingested food into biomass, and efficiency of conversion of digested food into biomass. Reproductive studies entailed observations of oothecal production, oviposition intervals, inter-oviposition intervals, mass of oothecae, oothecal dimensions, egg number, oothecal cannibalism, and hatching dates. Strongly canalized development was achieved by resilient compensatory responses indicative of altered physiological and behavioural features. Cockroaches developed and reproduced adequately even when nutrient concentration was reduced to 25% of the controls. The declines in various key parameters were considerably less than expected from the degree of dietary dilution. In addition, elevated consumption and enhanced conversion efficiencies strongly suggest that cockroaches normally function at submaximal levels. The applied relevance of this research entails possible ramifications into the regulation and control of cockroaches. Furthermore, such knowledge enhances our understanding of not only diverse lifestyles but also the degree of variability to which insects may modify life history features in response to resource supply. / Thesis / Master of Science (MS)

Selective feeding in response to depletion of particular reserves was examined in the American cockroach, Periplaneta americana. Animals deprived of specific nutrients and subsequently provided with dietary choices, responded so as to restore their altered reserves. Since two foods of differing energy content were used, the fundamental hypothesis of optimality theory could be tested (i.e. do cockroaches behave so as to maximize energy intake?). Adult male cockroaches were placed in a computer-monitored artificial habitat containing routes to shelter, water, protein and carbohydrate. Measures of behaviour were compared over treatments. Treatments included control cockroaches (no starvation), cockroaches fed agar (originally fed protein and sugar), protein-starved cockroaches (originally fed sugar only) and starved cockroaches (no food in the pre-treatment). In all treatments, more time was spent feeding than drinking. In controls, feeding on carbohydrate took precedence over protein (for intake and duration). Protein-starved cockroaches showed increased intake (over controls) for protein, as expected, but also increased intake for both carbohydrate and water. Starved and agar-fed cockroaches displayed decreased carbohydrate and water intake while protein consumption increased. The compensatory responses showed large initial peaks that gradually approached control behaviour. The results indicate that feeding behaviour is strongly responsive to reserve state and reserves act as an integral part of a dynamic system which operates homeostatically. The fact that depletion of the protein reserve resulted in increased ingestion of both protein and carbohydrate strongly suggests that reserves are linked. Considerable variation in daily feeding was observed which may be related to overshoot/undershoot responses typical of homeostatic systems where time lags exist. The results are strongly at variance with the predictions of optimal foraging theory. Cockroaches appear to feed to homeostatic set points, largely regulated by reserves. Reserves are largely ignored in optimal foraging theory. Furthermore, the animals regulate intake of nitrogen (protein) and/or energy, and do not simply maximize energy intake. / Thesis / Master of Science (MS)

No description available.

A quitosana é um biopolímero funcional com grande potencial de desenvolvimento, podendo gerar diferentes tipos de materiais com variadas funções. Conforme modificações na sua estrutura, a quitosana tem encontrado aplicações nas mais diversas áreas, possuindo um grande leque de aplicações. Apesar do crescente uso da quitosana e do aumento das pesquisas por novas aplicações, a prospecção de outras opções de fontes (que não crustáceos) de quitosana não têm sido consistentemente apresentadas. O objetivo do presente projeto é realizar a prospecção quantitativa e qualitativa de uma nova fonte renovável de quitosana. Temos como uma fonte alternativa para a produção de quitosana, os blatódeos que são comumente conhecidos como baratas. Eles são organismos terrestres que apresentam uma reprodução consideravelmente rápida, se adaptam aos mais variados ambientes e tem o custo de criação baixíssimo devido à sua fácil adaptação ao ambiente e alimentação. Além disso, os blatódeos não possuem sazonalidade, e ainda realizam ecdises, podendo-se utilizar as exúvias para a produção de quitosana. Foram determinados o processo e o rendimento do processo de obtenção de quitosana a partir de blatódeos (Phoetalia pallida). Os blatódeos foram submetidos a tratamento com solução de hidróxido de sódio 50% (p/v) em temperatura de 120 ºC por sete tempos diferentes (1, 2, 3, 6, 10 e 20 horas). As quitosanas obtidas foram caracterizadas mediante técnicas de espectroscopia no Infravermelho (FTIR), comportamento térmico (TG/DTG e DSC), difração de raios-x, viscosimetria e teste de solubilidade. A obtenção de quitosana a partir de blatódeos apresentou vantagens em relação à produção a partir de crustáceos: reduzido número de etapas do processo e dispensa o tratamento com HCl, que é um poluente. O processo de obtenção de quitosana teve rendimento de aproximadamente 15%, variando de acordo com o tempo de reação. De uma maneira geral, as quitosanas de barata apresentaram características semelhantes à quitosana de camarão. / Chitosan is a functional biopolymer with great development potential, which can generate different types of materials with several purposes. Depending on changes in its structure, chitosan has found applications in several areas, having a wide range of applications. Despite the increasing use of chitosan and the increase in research for new applications, the exploration of other options as sources of chitosan (other than shellfish) have not been consistently shown. The goal of this project is to conduct a quantitative and qualitative exploration of a new renewable source of chitosan. Blattaria, commonly known as cockroaches, are an alternative source for the production of chitosan. They are terrestrial organisms that present a considerably fast reproduction, adapt to many different environments and have a very low cost of growing, due to its easy adaptation to the environment and food. Moreover, the cockroaches don´t present seasonality and still perform ecdysis, where the exuvia can be used to produce chitosan. The process and the efficiency of the process of obtaining chitosan from the cockroaches, Phoetalia pallida, were determined: they were treated with a solution of sodium hydroxide 50% (w / v) at a temperature of 120 °C for seven different time periods (1, 2, 3, 6, 10 and 20 hours). Chitosans obtained therefrom were characterized by Infrared spectroscopy (FTIR), thermal behavior (TG / DTG and DSC), x-ray diffraction, viscosimetry and solubility test. Obtaining chitosan from cockroaches showed advantages over the production from shellfish: reduced number of process steps and not requiring treatment with HCl, which is a pollutant. The process of obtaining chitosan showed an efficiency of approximately 15%, depending upon the reaction time. In general, the cockroach chitosan showed characteristics similar to shrimp chitosan.

Cockroach salivary glands are innervated by dopaminergic and serotonergic neurons. Both transmitters elicit saliva secretion. We studied the distribution pattern of neurons containing gamma-aminobutyric acid ( GABA) and their physiological role. Immunofluorescence revealed a GABA-immunoreactive axon that originates within the subesophageal ganglion at the salivary neuron 2 (SN2) and this extends within the salivary duct nerve towards the salivary gland. GABA-positive fibers form a network on most acinar lobules and a dense plexus in the interior of a minor fraction of acinar lobules. Co-staining with anti-synapsin revealed that some putative GABAergic terminals seem to make pre-synaptic contacts with GABA-negative release sites. Many putative GABAergic release sites are at some distance from other synapses and at distance from the acinar tissue. Intracellular recordings from isolated salivary glands have revealed that GABA does not affect the basolateral membrane potential of the acinar cells directly. When applied during salivary duct nerve stimulation, GABA enhances the electrical response of the acinar cells and increases the rates of fluid and protein secretion. The effect on electrical cell responses is mimicked by the GABA(B) receptor agonists baclofen and SKF97541, and blocked by the GABAB receptor antagonists CGP52432 and CGP54626. These findings indicate that GABA has a modulatory role in the control of salivation, acting presynaptically on serotonergic and/or dopaminergic neurotransmission.

Inulase had received little attention and there were conflicting statements about its availability in animals.Adapted anthrone-sulfuric acid and Nelson-Somogyi reagents were used for identifying fructose concentration in inulin hydrolyzed by insect and aerobic bacteria extracts as a measure of inulase activity.Bacteria isolated from the insect’s gut were grown in nutrient agar and their extracts were used in hydrolyzing inulin. Aerobic bacteria-free insect extracts were obtained by injecting aureomycin into the gut of the cockroaches.There was no significant aureomycin effect on inulase production by the insects. The greatest inulase activity was around the gastric ceaca region. The major inulase requirement of the insects was met by gastric ceaca region production and not by the bacteria. The assertion that inulase may not be found in animal workd (Bernfeld 1962, Doby 1965, Hoar 1966) is unsupported. Periplaneta americana (Linnaeus) and Blaberus giganteus (Linnaeus) have inulase in their gastric caeca regions.Studies of inulase could lead to better understanding of cockroach physiology and their symbionts. If inulase is eventually synthesized in the laboratory a significant amount of inulin energy would become available to man through the use of synthetic inulase.Honors CollegeBall State UniversityMuncie, IN 47306

No description available.

A quitosana é um biopolímero funcional com grande potencial de desenvolvimento, podendo gerar diferentes tipos de materiais com variadas funções. Conforme modificações na sua estrutura, a quitosana tem encontrado aplicações nas mais diversas áreas, possuindo um grande leque de aplicações. Apesar do crescente uso da quitosana e do aumento das pesquisas por novas aplicações, a prospecção de outras opções de fontes (que não crustáceos) de quitosana não têm sido consistentemente apresentadas. O objetivo do presente projeto é realizar a prospecção quantitativa e qualitativa de uma nova fonte renovável de quitosana. Temos como uma fonte alternativa para a produção de quitosana, os blatódeos que são comumente conhecidos como baratas. Eles são organismos terrestres que apresentam uma reprodução consideravelmente rápida, se adaptam aos mais variados ambientes e tem o custo de criação baixíssimo devido à sua fácil adaptação ao ambiente e alimentação. Além disso, os blatódeos não possuem sazonalidade, e ainda realizam ecdises, podendo-se utilizar as exúvias para a produção de quitosana. Foram determinados o processo e o rendimento do processo de obtenção de quitosana a partir de blatódeos (Phoetalia pallida). Os blatódeos foram submetidos a tratamento com solução de hidróxido de sódio 50% (p/v) em temperatura de 120 ºC por sete tempos diferentes (1, 2, 3, 6, 10 e 20 horas). As quitosanas obtidas foram caracterizadas mediante técnicas de espectroscopia no Infravermelho (FTIR), comportamento térmico (TG/DTG e DSC), difração de raios-x, viscosimetria e teste de solubilidade. A obtenção de quitosana a partir de blatódeos apresentou vantagens em relação à produção a partir de crustáceos: reduzido número de etapas do processo e dispensa o tratamento com HCl, que é um poluente. O processo de obtenção de quitosana teve rendimento de aproximadamente 15%, variando de acordo com o tempo de reação. De uma maneira geral, as quitosanas de barata apresentaram características semelhantes à quitosana de camarão. / Chitosan is a functional biopolymer with great development potential, which can generate different types of materials with several purposes. Depending on changes in its structure, chitosan has found applications in several areas, having a wide range of applications. Despite the increasing use of chitosan and the increase in research for new applications, the exploration of other options as sources of chitosan (other than shellfish) have not been consistently shown. The goal of this project is to conduct a quantitative and qualitative exploration of a new renewable source of chitosan. Blattaria, commonly known as cockroaches, are an alternative source for the production of chitosan. They are terrestrial organisms that present a considerably fast reproduction, adapt to many different environments and have a very low cost of growing, due to its easy adaptation to the environment and food. Moreover, the cockroaches don´t present seasonality and still perform ecdysis, where the exuvia can be used to produce chitosan. The process and the efficiency of the process of obtaining chitosan from the cockroaches, Phoetalia pallida, were determined: they were treated with a solution of sodium hydroxide 50% (w / v) at a temperature of 120 °C for seven different time periods (1, 2, 3, 6, 10 and 20 hours). Chitosans obtained therefrom were characterized by Infrared spectroscopy (FTIR), thermal behavior (TG / DTG and DSC), x-ray diffraction, viscosimetry and solubility test. Obtaining chitosan from cockroaches showed advantages over the production from shellfish: reduced number of process steps and not requiring treatment with HCl, which is a pollutant. The process of obtaining chitosan showed an efficiency of approximately 15%, depending upon the reaction time. In general, the cockroach chitosan showed characteristics similar to shrimp chitosan.

No description available.