Comparative histological and biochemical studies were conducted with the flight muscles and mitochondria of several insect species to determine any correlation which exists between muscle structure and the metabolic activity of their mitochondria. Light microscopic examinations were used in the subcellular observations of these muscles. These included direct observations of freshly isolated material (wet mounts), as well as permanent preparations of transverse sections of some muscle fibers. Histological results were presented in a table which includes the muscle type, as well as the fiber, fibril, and mitochondria sizes of several insect species. The presence and abundance of mitochondria and their arrangement in straight rows between the fibrils, was shown to be common in the flight muscles of all insects investigated (except in the female cockroach, Periplaneta americana). In support of these results, a series of microphotographs showing a comparison of the features studied is presented. / Ph. D.

Two age factors were studied: the age of the roach at the time of testing, and the age of the female parent at the time reproduction occurred. Age groups from 1-3 days to 25-28 days were used to test the first factor and the first three egg eases were used to test the latter. Age was found to be a statistically significant factor when malathion, aldrin, and DDT were tested on both sexes of the normal strain. However, because of inconsistencies and a lack of differences of any great magnitude, it is believed that the differences in all but the aldrin tests were of no biological significance. In the aldrin tests it appeared that as the age of the roach increased, susceptibIlity gradually increased. The tests using aldrin on the Aldrin-resistant strain were significant for the females. Resistance in this strain appeared to increase from the 1-3 day age group until it reached a peak in the 10-12 day age group, then decreased to a level equal to or lower than that of the younger age groups. Statistical significance was found for the parental age factor in about one-half of the tests. However, it was of little biological significance because the variations were of a small magnitude and inconsistencies between the males and females occurred of ten. / Master of Science

1. Reciprocal crosses were made between a DDT-resistant and a nonresistant strain of the German cockroach. 2. The techniques employed in rearing the roaches and obtaining toxicological data on the different strains, as well as the genetical and statistical procedures, are described. 3. The toxicological data are presented in the form of regression lines with appropriate statistical analyses. 4. A table showing the relative resistance to DDT of the various strains involved in this study is included. 5. Several conclusions are drawn relative to the inheritance of resistance to DDF in the German cockroach. / Master of Science

German cockroach, Blattella germanica L., females of resistant and non-resistant strains carrying oothecae were exposed to filter paper impregnated with propoxur, malathion, and diazinon. Premature oothecal drop was monitored during the exposure period and for 24 hours thereafter. Determinations of female mortality were also made 72 h post-exposure. Oothecae from exposed females were observed for percentage egg hatch, time from exposure to hatch, percentage nymphal emergence, nymphal survival, and the percentage of nymphs able to move about freely 24 hours post-emergence. The comparisons of these factors were made not only on prematurely dropped oothecae but also on oothecae retained by females, and oothecae that were manually detached from females. Premature oothecae dropped and those manually detached were hatched on an insecticide treated surface. Premature oothecal drop occurred in all experiments, but was delayed 24 h in experiments with organophosphates. The mortality of treated females which prematurely dropped their oothecae was higher than females retaining them (73% vs. 53%). Percentage nymphal emergence and survival were reduced when oothecae were placed on an insecticide treated surface. The significantly higher survival of resistant strain nymphs (Carver, 60%, and Lynn Haven, 99%) in a comparison to nymphs of a susceptible strain (VPI, 45%) on insecticide treated surfaces provides evidence for resistance in first instar nymphs. A procedure for the quantitative comparison of the effects of different insecticides on oothecal-bearing females has been developed. Insecticides which cause a higher percentage of premature oothecal drop may reduce regrowth of a cockroach population when compared to materials which do not, even if the insecticides cause similar mortality. The extent to which population regrowth occurs depends on whether oothecae hatch on a treated surface, oothecal age, and environmental conditions. / Master of Science

This research concerns the effects that harborage limitation and habitat isolation have on German cockroach control in urban housing apartments. Standard Mason jar traps were used to survey cockroach populations, trap cockroaches for marking and population census, and detect cockroaches that moved from the original capture sites. Focus apartments (ie. apartments with large cockroach populations) were located and used for the two studies. Five focus apartments were used for the harborage limitation study. All harborage and harborage access in the kitchen and bathroom areas were sealed in three treatment apartments. These areas were not sealed in the two control apartments. Eight focus apartments were used for the habitat isolation study. Three treatment apartments had all accessways (holes and cracks) between the focus and the adjacent apartments sealed. Five control apartments were not sealed. Cockroaches in the three treatment apartments were captured, marked and released at the point of capture. Harborage limitation focus apartments were sprayed with 0. 5% chlorpyrifos in water and habitat isolation focus apartments were sprayed with a 0.25% synergized pyrethrin aerosol. Percentage control for the harborage limitation study was determined and no significant differences (P<0.1%) between treatment and control apartments were found. Percentage movement for the habitat isolation study was determined and no significant differences (P<0. 1%) between treatments and controls were noted. Neither harborage limitation nor habitat isolation would be recommended as a cockroach control technique unless they are used in concert with other control techniques. / Master of Science

This investigation represents the first thorough examination of chiasma frequency in the primitive orthopteroid insect, <u>Blattella germanica </u> (L.). The data obtained are useful both in advancing our knowledge of cockroach genetics and in stimulating comparative cytogenetic studies. A pilot study was conducted to ascertain appropriate sample sizes and to assess the feasibility of more extensive investigations. Experimental animals were reared in a constant temperature and humidity chamber and segregated according to whether they emerged from a first, second, or third ootheca. The testes of third to fourth instar male nymphs were removed, stained with acetic orcein, and examined for suitable numbers of cells at diplotene-diakinesis. Analysis of the chiasma frequency data showed a decrease in mean chiasmata per bivalent: 1.3325 ± 0.0184 for the first oothecal group, 1.2999 ± 0.0165 for the second oothecal group, and 1.2525 ± 0.0113 for the third oothecal group. The variances decline with the means. The chiasma frequency of a stock heterozygous for a reciprocal translocation involving two mid-sized chromosomes, eight and nine, was compared to the wild-type freq9encies. In comparison with the first oothecal group, an elevated chiasma frequency, 1.4176 ± 0.0062 chiasma per bivalent, was found. The translocation had the effect of raising chiasma frequency in the two bivalents involved. No interchromosomal effect on chiasma frequency was observed, due to the presence of the translocation. It was noted that in B. germanica, chiasma frequency is probably not positively correlated with bivalent length. / Master of Science

In an attempt to demonstrate the role of insects as possible carriers of pathogenic bacterial organisms this investigation has been concerned with the determination of the microbial population associated both internally and externally with the common house fly and three species of the cockroach.

During recent years most of the successful developments in pyrethroids have been primarily concerned with structural or compositional variations. As a part of our continuing interest in pyrethroid insecticides, nitrogen-containing compounds having pyrethroid-like structures were synthesized. Seven prolinate compounds, N-(substituted)-phenyl-prolinates and N-carbobenzoxy-prolinates were coupled with known pyrethroid alcohols. These structural variations which "locked in" a specific conformation between the nitrogen and chiral a-carbon in the acid moiety of fluvalinate were studied to determine the influence of certain conformations on insecticidal toxicity. The toxicity data for the prolinate compounds showed intermediate mortality against nonresistant cockroaches. It was concluded that the conformation imposed by the proline ring portion of the esters was probably close to the favored conformation for interaction of fluvalinate-like pyrethroids with the insect receptor site. A second series of nitrogen-containing compounds, twenty-five carbamate esters resulting from the condensation of N-isopropyl-(substituted)-anilines and N-alkyl-(substituted)-benzylamines with appropriate pyrethroid alcohols were studied for insecticidal activity. These studies were conducted on pyrethroid-susceptible houseflies. Some of the carbamate esters exhibited high toxicity when synergized by piperonyl butoxide. For example, the toxicity ( LD 50 ) of O-a-cyano-3-phenoxyfaenzyl-N-a,a-dimethyl-4-bromo-benzyl carbamate was 0.012 ug/g, which is significantly greater than that reported for the potent pyrethroid, fenvalerate. Correlations of insecticidal activity with respect to structure and conformational factors of the carbamate esters have been made. The N-isopropyl substituent decreases insecticidal activity in the N-benzyl-derived compounds, while the N-isopropyl substituent enhances activity in the N-phenyl-derived compounds. Certain substituents on the phenyl ring of both analogs greatly affect insecticidal potency of the carbamate esters. Also, some alkyl substituents (especially, a,cx-dimethyl and a-cyclopropyl groups) on the benzylic carbon of the benzylamine series enhance toxicity. The a,a-dimethyl branching of the N-benzyl carbamate approximates the steric shape given by the gemdimethyl group for conventional cyclopropane ring-containing pyrethroids. The N-benzyl compounds are significantly synergized by piperonyl butoxide, particularly those in which the carbamate nitrogen atom is mono-substituted.

Made available in DSpace on 2016-04-28T20:17:28Z (GMT). No. of bitstreams: 1 2008 - Pablo Waldeck Goncalves de Souza.pdf: 2011389 bytes, checksum: 2d903c70e0f497dfa879d5f386e128c6 (MD5) Previous issue date: 2008-03-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The objective of this paper was determined the presence of Cryptococcus neoformans in cockroach (Periplaneta americana) collected in public places. The motivation for this research was based on the fact that this species of cockroach is synanthropic and vehicle of several pathogenic agents for man and animals. The insect were collected already dead and also collected alive using different traps, at all, were 150 samples. The research of the presence of the agents in the insects was made in Laboratory of Pathogenic and Environmental Yeasts, Department of Microbiology and Immunology Veterinary, Institute of Veterinary, UFRRJ, by the process of the exoskeleton and the internal content of then, sowing in cultivation medium containing dopamine. The confirmations of isolation were made by macromorfology and micromorfology test, realization of auxanographic method and complementally proofs. Was not obtained isolation of Cryptococcus neoformans of exoskeleton. Were obtained 5 isolated (3%), starting by the content of the insects that, after the serogrouping in CGB medium, show them self as belonging to AD serum group. Test show that 80% of the stumps are big producing of phospholipase and 100% big producing of protease. We considerate that the cockroaches of the species Periplaneta americana are,potentially, a vector for the studied yeast. / O objetivo deste trabalho foi determinar a presen?a de Cryptococcus neoformans em baratas (Periplaneta americana) recolhidas de ambientes p?blicos. A motiva??o para esta pesquisa deve-se ao fato desta esp?cie de barata ser sinantr?pica e veiculadora de v?rios agentes patog?nicos para o homem e animais. Os insetos foram recolhidos mortos e tamb?m capturados vivos por meio de duas diferentes armadilhas, totalizando 150 amostras. A pesquisa da presen?a do agente nos insetos foi feita no Laborat?rio de Leveduras Patog?nicas e Ambientais, Depto de Microbiologia e Imunologia Veterin?ria, Instituto de Veterin?ria, UFRRJ, por processamento do exoesqueleto e do conte?do interno dos mesmos, com semeadura em meio de cultivo contendo dopamina. As confirma??es de isolamento foram realizadas por meio de testes de macromorfologia, micromorfologia, realiza??o de auxanograma e provas complementares. N?o foi obtido isolamento de Cryptococcus neoformans de exoesqueleto. Foram obtidos 5 isolamentos (3%) a partir do conte?do interno dos insetos que, ap?s sorogrupagem em meio CGB revelaram-se como pertencentes ao sorogrupo AD. Testes evidenciaram que 80% das cepas s?o forte produtoras de fosfolipase e 100% forte produtoras de protease. Consideramos que as baratas da esp?cie Periplaneta americana s?o um potencial vetor para a levedura estudada.

While the locomotion performance of legged robots over flat terrain or known obstacles has improved over the past few decades, they have yet to equal the performance of their animal counterparts over variable terrain. This work analyzes a multi-legged reduced order model of cockroach locomotion on variable slopes which will be used as an inspiration for a future sprawled posture legged robot. The cockroach is modeled as a point mass, and each leg of the cockroach is modeled as a massless, tangentially rigid, linearly elastic spring attached at the center of mass. All of the springs are actuated to allow changes in energy to the system. This is accomplished by varying the force free length of each leg in a feed-forward manner without reliance on feedback to change the actuation scheme. Fixed points of the model are found using a numerical solver that varies the velocity and phase shift parameters while leaving all other parameters at fixed values selected to match true cockroach motion. Each fixed point is checked for stability and robustness representing how effective the model is at staying on the predetermined gait, and transport cost as a measure of how efficient this gait is. Stable and robust fixed points were successfully found for the range of heading angles encompassing those of representative cockroach motion at each slope. Cockroaches may select the gait used based on stability or efficiency. Thus, additional fixed points were found in combination with a search routine that varies the leg actuation parameters in order to optimize either stability or metabolic efficiency, gaining insights into why cockroaches use the gaits that they do. Optimized fixed points were found based on four different leg functional combination families depending on whether each leg pushes or pulls. Optimized fixed point gaits exist for every incline slope studied between level ground and vertical slopes, at a range of initial heading angles that encompass those typically used by cockroaches. The selected gaits using both a stability based and an efficiency based optimization on the modeled cockroach are very similar. Both are also similar to gaits used by real cockroaches. The forces generated by the model are qualitatively similar to the experimental forces. / Graduation date: 2012