Sex-biased genes are expressed at higher levels in one sex and contribute to phenotypic differences between males and females, as well as overall phenotypic variation within and among populations. Venom has evolved primarily for predation and defense, making venom expression a highly variable phenotype as a result of local adaptation. Several scorpion species have shown both intraspecific and intersexual venom variation, and males have been observed using venom in courtship and mating, suggesting the existence of venom-specific, sex-biased genes that may contribute to population divergence. We used reversed-phase high-performance liquid chromatography (RP-HPLC), Agilent protein bioanalyzer chips, nano-liquid chromatography mass spectrometry (nLC/MS/MS), and median lethal dose (LD) assays in fruit flies (Drosophila melanogaster) and banded crickets (Gryllodes sigillatus) to investigate proteomic and functional venom variation within and among three Florida populations of the Hentz striped scorpion (Centruroides hentzi). We found significant venom variation among populations, with females, not males, being responsible for this divergence. We also found significant variation in venom expression within populations, with males contributing more to within population variation than females. Our results provide evidence that male and female scorpions experience different natural and sexual selective pressures that have led to the expression of sex-biased venom genes and that these genes may be consequential in population divergence.

Toxoplasmosis is a worldwide zoonotic disease but information regarding domestic animals in Central America is scarce and fragmented. The aim of this study was to determine the seroprevalence of Toxoplasma gondii in domestic cats and dogs in different metropolitan regions of Panama. A total of 576 samples were collected; sera from 120 cats and 456 dogs were tested using a commercial indirect enzyme-linked immunosorbent assay (ELISA). The overall seroprevalence of IgG antibodies was 30.73%. There is high seroprevalence of T. gondii in cats and dogs in the metropolitan regions around the Panama Canal; however, differences between these species were not significant. Statistical analysis indicated that there are relevant variables, such as the age of animals, with a direct positive relationship with seroprevalence. None of the variables related to animal welfare (veterinary attention provided, type of dwelling, and access to green areas and drinking water) were associated with seropositivity.

RESUMO:Aedes aegypti é uma espécie de ampla distribuição geográfica, e sua presença foi registrada nas ilhas de Cabo Verde. Pelo fato de a sua bioecologia estar sendo atualmente estudada em várias partes do mundo, e também por ter sido realizado o primeiro registro de uma epidemia de dengue no país, decidiu-se pela realização deste levantamento. O trabalho foi realizado entre fevereiro e março de 2010, quando foram inspecionadas seis das dez ilhas que compõem o arquipélago. Os fatores avaliados durante o levantamento foram número, tipo e localização dos recipientes, assim como a presença das formas larvais de Ae. aegypti. Os resultados demonstraram a presença de 2,4 recipientes/residência inspecionada, registrando-se um total de 118 criadouros, sendo estes mais frequentes nas residências abandonadas. A condição de risco foi significativamente diferente entre as ilhas, sendo superior para Boa Vista. Todas as ilhas avaliadas demonstraram tendência significativa à diminuição do número de criadouros, com exceção da ilha de Fogo (GLM; p ≤ 0.05). Os recipientes mais frequentemente registrados foram os barris (> 50 L) (42.6%), localizados tanto no interior quanto no exterior das residências. Como criadouros, foram registrados com mais frequência os barris (> 50 L), tanques (> 200 L) e tanques plásticos (> 50 L) (Teste t; p ≤ 0.05). PALAVRAS-CHAVE:Aedes aegypti; Cabo Verde; larva; insetos vetores. ABSTRACT:Aedes aegypti is a species of wide geographical distribution, and its presence is registered on the islands of Cape Verde. Because its bioecology is being currently studied in several parts of the world, and since the first record of a dengue epidemic has been accomplished in the country, we decided to conduct this survey. The study was carried out between February and March, 2010, when six out of the ten islands of the archipelago were inspected. The factors evaluated during the survey were number, type and location of containers, as well as the presence of larval forms of Ae. aegypti. Results showed the existence of 2.4 containers/inspected houses, registering a total of 118 breeding sites, which are more common among abandoned buildings. The risk condition was significantly different between islands, being higher for Boa Vista. All evaluated islands showed a significant decreasing tendency of breeding sites, except for Fogo island (GLM; p ≤ 0.05). The barrels were the containers most frequently recorded (> 50 L) (42.6%), located both inside and outside the houses. As breeding sites, barrels (> 50 L), tanks (> 200 L) and plastic tanks (> 50 L) were more common (t test; p ≤ 0.05).

Foi determinada a prevalência de Ehrlichiose canina entre animais atendidos no Complexo Hospitalário Veterinário do Corozal da Faculdade de Medicina Veterinária da Universidade de Panamá. O levantamento foi realizado de forma retrospectiva com dados obtidos no período de janeiro de 2004 a dezembro de 2009. Para o trabalho, foram utilizados os registros dos casos clínicos de ehrlichiose canina, confirmados através de esfregaço sanguíneo, a raça e os aspectos demográficos (idade, sexo e local de origem) de cada animal. Os resultados revelaram que 10,12% dos animais atendidos (n = 1.452) mostraram-se positivos para o problema no período em análise. Esses animais eram de ambos os sexos com idade media de aproximadamente 3,6 anos. A prevalência mensal registrada foi de 9,98%, com taxa de infecção significativamente superior em 2008 (14,83%). O número de casos positivos foi significativamente superior nos meses de março, maio e setembro e menor no mês de fevereiro, destacando-se haver densidade de casos igual ou superior à média de maio a outubro. A raça e o local de origem dos animais foram identificados como fatores de risco.