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This project focused on improving the in vitro rearing methods of Toxoneuron nigriceps, an important biological control agent of Heliothis virescens, by supplementing the rearing media with the host hemolymph. T. nigriceps larvae of different ages were incubated in the artificial rearing media. The growth (increase in length and width), development (molting), and survival of the incubated larvae were observed. Changes in osmotic pressure of the rearing media before and after incubation were evaluated. The protein profiles of day 1, 3 and 5 hemolymph samples of the parasitized and unparasitized H. virescens fifth instar larvae, used in the artificial rearing media, were determined. Host hemolymph improved the growth and development of T. nigriceps larvae in the artificial rearing media except in the case of new and early first instar larvae. Osmotic pressure of all media showed a significant decrease after the incubation of the larvae except media incubated with the new first instar larvae indicating that the older larvae absorbed and utilized more of the nutrients from the rearing media than the younger larvae. Growth and development was higher in the semisolid media than in the liquid media. In the artificial rearing media, the late first instar T. nigriceps larvae molted to second instars and a few of them molted to third instars. The early and late second instar larvae incubated in the artificial media also grew well and molted to third instars. Some of the in vitro reared third instar larvae demonstrated behavioral changes that could be expressed as the preparation for cocoon formation or pupation, however neither a cocoon nor pupation occurred. No qualitative differences in the protein titers were detected between hemolymph of the parasitized and unparasitized fifth instar H. virescens larvae. There was a significant increase in the protein concentration in both unparasitized and parasitized H. virescens larvae as the age increased. This increase in the protein concentration showed a positive effect on the growth and development of T. nigriceps larvae indicating that availability of nutrients was an important factor for the growth of T. nigriceps larvae in vitro.

Artificial rearing of infant rats is a useful method for studying the role of early experiences in neural and behavioural development because it permits precise control over key features of the early environment without maternal influence. The present thesis examined the behavioural response of artificially reared rats towards natural and drug-mediated rewards, as well as novel environments. Male Sprague-Dawley rats were separated from their mother and litter-mates starting on post-natal day five and reared artificially (AR, n = 39), or they were reared naturally with a foster mother and litter (MR, n = 43). On post-natal day 21, half the rats from each rearing group were housed in isolation and the other half were group-housed with 3-4 rats per cage. Following three weeks in their respective housing conditions, all rats were exposed to three behavioural tests in the following order: open field, elevated plus-maze and sucrose preference. Additionally, one of the two cohorts used in adolescent behavioural testing was later tested in adulthood for conditioned place preference in response to morphine injection (intraperitoneal, 10 mg/kg). Adolescent AR rats were found to be more active in the open field and in the elevated plus-maze than MR rats. Furthermore, although there were no differences between the groups in fearfulness in the open field, in their first experience on the elevated plus-maze AR rats were more anxious than MR rats in exploring the open arms. AR rats also showed increased preference for sucrose consumption relative to chow, although their overall caloric intake during the 1h test was lower than that of MR rats. In adulthood, AR rats displayed a stronger conditioned place preference response to morphine. There were no significant effects of housing condition on any of these outcome measures. These findings support the potential of this model to contribute to the understanding of the role of early experience in the development of behavioural motivation.

Social interactions in early life influence the organization of neural and behavioural systems of developing mammalian young. Deprivation of social interactions with the primary caregiver and other immediate conspecifics (early social deprivation) has lasting consequences on behavioural functioning in later life. The purpose of this thesis was to investigate how early social deprivation affects the motivational aspects of behaviour in the context of appetitive stimuli. Rats were reared in complete isolation from the mother and litter using the method of artificial rearing (AR). Control rats were maternally reared (MR). In adulthood, rats were tested in a series of behavioural paradigms designed to assess the motivational impact of primary food reward and reward-related cues on food-seeking behaviour. AR increased the behavioural responsiveness of rats to the motivational impact of reward-related cues, but not to primary rewards themselves. Specifically, there were no significant effects of AR on food consumption or goal-directed instrumental responding for food. However, AR enhanced instrumental responding triggered by a previously conditioned reward cue. AR also increased the expression of approach behaviour towards a localizable conditioned reward cue and instrumental responding when the same cue was used as a reinforcer. An assessment of the mediating factors during development revealed that the lack of tactile stimulation normally received from the mother, but not sustained exposure to the stress hormone corticosterone, contributed to the long-term effects of AR. These findings represent a potential link between early-life social adversity and vulnerability to the development of problems with behavioural inhibition and attention in the presence of appetitive environmental cues.

Social interactions in early life influence the organization of neural and behavioural systems of developing mammalian young. Deprivation of social interactions with the primary caregiver and other immediate conspecifics (early social deprivation) has lasting consequences on behavioural functioning in later life. The purpose of this thesis was to investigate how early social deprivation affects the motivational aspects of behaviour in the context of appetitive stimuli. Rats were reared in complete isolation from the mother and litter using the method of artificial rearing (AR). Control rats were maternally reared (MR). In adulthood, rats were tested in a series of behavioural paradigms designed to assess the motivational impact of primary food reward and reward-related cues on food-seeking behaviour. AR increased the behavioural responsiveness of rats to the motivational impact of reward-related cues, but not to primary rewards themselves. Specifically, there were no significant effects of AR on food consumption or goal-directed instrumental responding for food. However, AR enhanced instrumental responding triggered by a previously conditioned reward cue. AR also increased the expression of approach behaviour towards a localizable conditioned reward cue and instrumental responding when the same cue was used as a reinforcer. An assessment of the mediating factors during development revealed that the lack of tactile stimulation normally received from the mother, but not sustained exposure to the stress hormone corticosterone, contributed to the long-term effects of AR. These findings represent a potential link between early-life social adversity and vulnerability to the development of problems with behavioural inhibition and attention in the presence of appetitive environmental cues.

Artificial rearing of infant rats is a useful method for studying the role of early experiences in neural and behavioural development because it permits precise control over key features of the early environment without maternal influence. The present thesis examined the behavioural response of artificially reared rats towards natural and drug-mediated rewards, as well as novel environments. Male Sprague-Dawley rats were separated from their mother and litter-mates starting on post-natal day five and reared artificially (AR, n = 39), or they were reared naturally with a foster mother and litter (MR, n = 43). On post-natal day 21, half the rats from each rearing group were housed in isolation and the other half were group-housed with 3-4 rats per cage. Following three weeks in their respective housing conditions, all rats were exposed to three behavioural tests in the following order: open field, elevated plus-maze and sucrose preference. Additionally, one of the two cohorts used in adolescent behavioural testing was later tested in adulthood for conditioned place preference in response to morphine injection (intraperitoneal, 10 mg/kg). Adolescent AR rats were found to be more active in the open field and in the elevated plus-maze than MR rats. Furthermore, although there were no differences between the groups in fearfulness in the open field, in their first experience on the elevated plus-maze AR rats were more anxious than MR rats in exploring the open arms. AR rats also showed increased preference for sucrose consumption relative to chow, although their overall caloric intake during the 1h test was lower than that of MR rats. In adulthood, AR rats displayed a stronger conditioned place preference response to morphine. There were no significant effects of housing condition on any of these outcome measures. These findings support the potential of this model to contribute to the understanding of the role of early experience in the development of behavioural motivation.

In most mammals, nutritive suckling is critical during the early neonatal period. The genioglossus (GG) muscle in rat plays an important role in protruding the tongue for efficient suckling. The purpose of this study was to examine the contractile properties and myosin heavy chain (MHC) phenotype of the GG following an early period of artificial rearing, which reduced nutritive suckling. Beginning at three days of age Sprague-Dawley rats were fed via implanted gastric cannula until postnatal day 14 (P14). At P14, artificially reared (AR) rat pups were either placed with a lactating dam until the end of the weaning period and allowed to mature until postnatal day 42 (P42), or anesthetized and prepared for physiological experimentation. GG contractile properties at P14 and P42 in AR and dam reared (DR) rats were obtained with a force transducer and digital recording system through stimulation of the medial branch of the hypoglossal nerve. Following physiological experimentation, muscle samples were removed and stored for MHC analysis. Comparisons were made between AR and DR groups at P14 and P42. At P14 maximum tetanic tension and fatigue index were lower in the AR group than the DR group and no differences were found in MHC distribution. By day 42, AR rats had a higher fatigue index that DR rats and DR rats had a higher percentage of MHCIIa than AR rats. The artificial rearing technique employed in this study was adequate to produce chronic changes in fatigue resistance and MHC distribution in GG muscle. GG muscle of premature human infants requiring early artificial feedings may develop similar changes in their contractile characteristics and MHC phenotype.

Made available in DSpace on 2016-04-28T14:57:34Z (GMT). No. of bitstreams: 1 2008 - Alice Teodorio Lixa.pdf: 2009465 bytes, checksum: a5ff9f635d75eab4106b026e084105fb (MD5) Previous issue date: 2008-06-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Among the natural enemies of agriculture pests, the Coccinellidae predators are detached. Some coccinellids only complete their development and produce viable eggs and progenies when they consume their preferred prey. However, when this prey is scarce or in presence of a prey of low quality, certain coccinellids feed on alternative food resources, such as extra floral nectar and pollen, to guarantee their survivorship. Thus, the absence of these floral resources limits the occurrence and abundance of ladybeetles in the agroecosystems. Due to these characteristics, the coccinellids have great potential for being managed by the three strategies of biological control: classic, augmentative and conservation. However, to use the coccinellids as biological control agent, more information about their biology and ecology are still necessary. In this context, the present work was conducted with the general objective of producing information about ecological and biological aspects of the Coccinellidae. These approaches are in the Chapters I and II, respectively. In the Chapter I, the studies aimed to determine if Anethum graveolens (dill), Coriandrum sativum (coriander) and Foeniculum vulgare (sweet fennel) favor the abundance of Coccinellidae; to evaluate the potential of these aromatic plants to provide vital resources for these predators; to determine the species diversity of these insects attracted by these plants; and to characterize their community structure. The experiment was carried out in an integrated crop-livestock organic production area (Seropedica/RJ, Brazil) in a completely randomized design with three treatments (aromatic plants) and three replicates. From September 14th, 2007 to January 21st, 2008, samplings of adults and immature stages of ladybeetles were realized. Besides an unidentified species of Chilocorini, Coleomegilla maculata, Coleomegilla quadrifasciata, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Olla v-nigrum and Hippodamia convergens were collected. The dill provided significant increase in the abundance of coccinellids in relation to the coriander and sweet fennel. These three aromatic vegetal species were used as ovipositon sites and shelter for immature forms and adults of ladybeetles. The dill and sweet fennel were also used as mating sites and proved food resources (pollen and/or alternative prey). The principal species visiting these aromatic plants were C. sanguinea, H. convergens, and E. connexa (more frequent, constant and dominant). In the Chapter II, the studies aimed to determine biology aspects of Coleomegilla maculata and Eriopis connexa feed on two diets: ultraviolet-unviable and frozen eggs of Anagasta kuehniella (Lepidoptera: Pyralidae) and the alive aphids of Lipaphis erysimi (Hemiptera: Aphididae) under laboratory condition (25 ? 1?C, relative humidity of 70 ? 10%, and photophase of 12 hours). The experimental design was complete randomized in a 2x2 split-plot arrangement (two ladybeetle species and two diets). In general, the biological characteristics of C. maculata and E. connexa were similar, when their larvae and adults fed on the two diets. Both diets were suitable for C. maculata and E. connexa, keeping their development and oviposition for a generation, and the eggs of A. kuehniella still maintained the rearing of these ladybeetles for one more generation. / Entre os inimigos naturais de pragas agr?colas, destacam-se os Coccinellidae predadores. Alguns coccinel?deos s? completam seu desenvolvimento e produzem ovos e prog?nie vi?vel quando consomem sua presa preferencial. Todavia, quando esta presa est? escassa ou na presen?a de uma presa de qualidade inferior, certos coccinel?deos alimentam-se de alimentos alternativos, tais como n?ctar extrafloral e p?len, para garantir sua sobreviv?ncia. Desse modo, a aus?ncia desses recursos florais limita a ocorr?ncia e abund?ncia de joaninhas nos agroecossistemas. Devido essas caracter?sticas, os coccinel?deos apresentam grande potencial para serem manejados por meio do controle biol?gico cl?ssico, aumentativo e conservativo. Todavia, para usar os coccinel?deos como agente de controle biol?gico, mais informa??es sobre sua biologia e ecologia s?o ainda necess?rias. Neste contexto, o presente trabalho foi realizado com o objetivo geral de gerar informa??es sobre aspectos ecol?gicos e biol?gicos dos Coccinellidae, sendo esses temas abordados nos Cap?tulos I e II, respectivamente. No cap?tulo I, os estudos foram conduzidos com os seguintes objetivos: determinar se Anethum graveolens (endro), Coriandrum sativum (coentro) e Foeniculum vulgare (erva-doce) favorecem a abund?ncia de Coccinellidae; avaliar o potencial dessas esp?cies arom?ticas como provedoras de recursos vitais para esses predadores; determinar a diversidade de esp?cies desses insetos atra?dos por essas plantas; e caracterizar a estrutura de sua comunidade. O experimento foi conduzido em ?rea de produ??o org?nica integrada animalvegetal (Serop?dica/RJ), em delineamento de blocos casualizados, com tr?s tratamentos (esp?cies arom?ticas) e tr?s repeti??es. De 14 de setembro de 2007 a 21 de janeiro de 2008, foram realizadas amostragens de adultos e formas imaturas de joaninhas. Al?m de uma esp?cie n?o identificada da tribo Chilocorini, coletou-se Coleomegilla maculata, Coleomegilla quadrifasciata, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Olla v-nigrum e Hippodamia convergens. O endro proporcionou aumento significativo na abund?ncia de coccinel?deos em compara??o ao coentro e ? erva-doce. Essas tr?s esp?cies arom?ticas foram usadas como s?tios de oviposi??o e abrigo para formas imaturas e adultas de joaninhas. O endro e a erva-doce tamb?m foram utilizados como s?tios de acasalamento e de alimenta??o pelas joaninhas. As principais esp?cies visitantes das arom?ticas foram C. sanguinea, H. convergens e E. connexa (mais freq?entes, constantes e dominantes). No cap?tulo II, os estudos foram conduzidos com os seguintes objetivos: 1) determinar aspectos biol?gicos de C. maculata e E. connexa alimentadas com duas dietas: ovos de Anagasta kuehniella (Lepidoptera: Pyralidae) inviabilizados com ultravioleta e congelados e pulg?es vivos de Lipaphis erysimi (Hemiptera: Aphididae), em condi??es de laborat?rio (25?1?C, 70?10% UR e fotofase de 12 horas). O delineamento foi inteiramente casualizado em arranjo fatorial 2 x 2 (duas esp?cies de joaninhas e duas dietas). No geral, as caracter?sticas biol?gicas de C. maculata e E. connexa foram bem semelhantes, quando suas larvas e adultos se alimentaram das duas dietas. Ambas as dietas foram adequadas para C. maculata e E. connexa, assegurando seu desenvolvimento e oviposi??o por uma gera??o e os ovos de A. kuehniella permitiram ainda manter a cria??o dessas joaninhas por mais uma gera??o.

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