The ADH (alcohol dehydrogenase) system is one of the earliest known models of molecular evolution, and is still the most studied in Drosophila. Herein, we studied this model in the genus Anastrepha (Diptera, Tephritidae). Due to the remarkable advantages it presents, it is possible to cross species with different Adh genotypes and with different phenotype traits related to ethanol tolerance. The two species studied here each have a different number of Adh gene copies, whereby crosses generate polymorphisms in gene number and in composition of the genetic background. We measured certain traits related to ethanol metabolism and tolerance. ADH specific enzyme activity presented gene by environment interactions, and the larval protein content showed an additive pattern of inheritance, whilst ADH enzyme activity per larva presented a complex behavior that may be explained by epistatic effects. Regression models suggest that there are heritable factors acting on ethanol tolerance, which may be related to enzymatic activity of the ADHs and to larval mass, although a pronounced environmental effect on ethanol tolerance was also observed. By using these data, we speculated on the mechanisms of ethanol tolerance and its inheritance as well as of associated traits.

O objetivo deste trabalho foi avaliar alterações histomorfológicas na região do osso cortical de frangos de corte alimentados, nas fases de crescimento e engorda, com rações contendo cinco diferentes fontes de fósforo - fosfato dicálcico, superfosfato simples, superfosfato triplo, fosfato monoamônio e fosfato de rocha de Araxá. Imagens histológicas foram digitalizadas, segmentadas em regiões de interesse (ROI) e analisadas por meio de algoritmos desenvolvidos no ambiente de programação SCILAB. Consideraram-se onze características para descrição das imagens: porcentagem de osso por área, área da ROI, perímetro da ROI, alongamento da ROI, ângulo da ROI, os respectivos desvios-padrão dessas medidas, a entropia dos ângulos das ROI e uma medida orientada de textura (lacunaridade). A substituição do fosfato dicálcico, nas rações de crescimento e engorda, por qualquer uma das outras fontes de fósforo testadas, causou mudanças significativas na histomorfologia do córtex ósseo dos frangos de corte, tais como: menor porcentagem de osso por área, aumento da área das lacunas e menor homogeneidade da matriz. As alterações foram mais pronunciadas nos tratamentos que receberam fosfato de rocha de Araxá, fonte de maior nível de flúor, do que nos tratamentos com superfosfato simples, superfosfato triplo e fosfato monoamônio, os quais foram semelhantes entre si.

The objective of this work was to identify alterations in the histomorphology of the cortical bone tissue of broilers submitted to growing and finisher rations formulated with five different sources of phosphorus: dicalcium phosphate, simple superphosphate, triple superphosphate, monoammonium phosphate and Araxá rock phosphate. Histological images had their components segmented, and were called regions of interest (ROI). Images were analyzed through developed algorithms, using the SCILAB mathematical environment. Eleven features were considered in order to obtain a complete description of the bone images: percentage of bone by area, ROI area, ROI perimeters, ROI elongation, ROI angle and their respective standard deviations, besides entropy of ROI angles and a texture-oriented measure (lacunarity). The substitution of dicalcium phosphate in growing and finisher rations for any other tested source of phosphorus caused significant changes on the hystomorphology of the cortical broilers bones, for example: diminution of bone percentage by area, increase of lacuna area and worse matrix homogeneity. Changes were more pronounced in the Araxá rock phosphate treatments, with the highest fluorine content, than in simple superphosphate, triple superphosphate and monoammonium phosphate treatments, which were similar.

Partial cytochrome b and 12S rDNA mitochondrial DNA sequences of eight representatives of the Ramphastidae family were analyzed. We applied the linearized tree method to identify sequences evolving at similar rates and estimated the divergence times among some of the taxa analyzed. After excluding Ramphastos tucanus and Capito dayi from our data set, the remaining taxa presented a constant rate of DNA substitution, and branch lengths could be re-estimated with a clock constraint using the maximum likelihood method. Branch lengths were calibrated assuming that Galliformes and Piciformes split around 100 million years ago (mya). Our results indicate that Ramphastinae, and probably Capitoninae, diverged from other Piciformes in the Late Cretaceous (~82 mya), suggesting that Piciformes is another avian order that survived the mass extinction event occurred 65 mya at the Cretaceous/Tertiary (K/T) boundary. The divergence times estimated within the Ramphastinae genera cover the period from the Middle Eocene (around 47 mya) through the Late Miocene (9.5 mya). Our estimate of divergence time is coincidental with the split of the African and the South American continents and other intense geologic activities and modifications of the areas which correspond to the current Neotropics. These events might have influenced the diversification of Ramphastinae in South America.