Ethanol fuel improves pitfall traps through rapid sinking and death of captured orthopterans.

The choice of killing solutions for pitfall traps can influence sampling and is highly dependent on the objectives of each study. It is becoming increasingly common, however, and is more environmentally friendly, to use the same organisms to extract information for different kinds of studies. The killing solution should, therefore, be able to sample local active organisms, as well as maintain the integrity of their organs, tissues, and macromolecules. In a previous work, we showed that using ethanol fuel as a killing solution maintains the integrity of the specimens and enhances the Orthoptera richness and abundance of samples. In the current study, we evaluated two explanations for this pattern. We set up a field experiment to test whether ethanol fuel is attractive for orthopterans, and we investigated in the laboratory whether individuals of Gryllus sp. sink or die faster in ethanol fuel than in other killing solutions. Our results allowed us to refute the hypotheses of attraction caused by ethanol fuel and showed that the higher sampling efficiency of ethanol fuel is directly linked to the specimens sinking and dying faster than in other killing solutions. Thus, in addition to taxonomic, anatomical, and molecular studies, we recommend ethanol fuel for sampling organisms active in the litter in ecological studies.

Classification and putative origins of Brazilian porcine circovirus 2 inferred through phylogenetic and phylogeographical approaches.

Porcine circovirus 2 (PCV2) is the major causative agent of postweaning multisystemic wasting syndrome (PMWS) and is associated with different syndromes affecting pigs. The PCV2 genome has three main open reading frames (ORFs) among which the ORF2 encodes the capsid protein. In this study, the ORF2 nucleotide sequences of 30 Brazilian isolates were analyzed. The sequences were compared to other GenBank sequences using phylogenic and phylogeographic approaches. Our results show high sequence variability in Brazil, since, in this work, the Brazilian isolates were classified into subgroup 1AB, 2D and 2, which reveals that the virus was introduced in Brazil more than once. On the other hand, most of Brazilian isolates seem to be derived from only one introduction. According to the data from the Pig Breeders' Association, the multiple introductions of the virus probably occurred through the import of animals with the asymptomatic form of the virus or through the import of contaminated semen. The results point to the necessity of implementing programs aimed at selecting sows in order to avoid the import of animals infected by Group 1 PCV2.

Molecular characterization of Hepatozoon sp. from Brazilian dogs and its phylogenetic relationship with other Hepatozoon spp.

To characterize phylogenetically the species which causes canine hepatozoonosis at two rural areas of Rio de Janeiro State, Brazil, we used universal or Hepatozoon spp. primer sets for the 18S SSU rRNA coding region. DNA extracts were obtained from blood samples of thirteen dogs naturally infected, from four experimentally infected, and from five puppies infected by vertical transmission from a dam, that was experimentally infected. DNA of sporozoites of Hepatozoon americanum was used as positive control. The amplification of DNA extracts from blood of dogs infected with sporozoites of Hepatozoon spp. was observed in the presence of primers to 18S SSU rRNA gene of Hepatozoon spp., whereas DNA of H. americanum sporozoites was amplified in the presence of either universal or Hepatozoon spp.-specific primer sets; the amplified products were approximately 600bp in size. Cloned PCR products obtained from DNA extracts of blood from two dogs experimentally infected with Hepatozoon sp. were sequenced. The consensus sequence, derived from six sequence data sets, were blasted against sequences of 18S SSU rRNA of Hepatozoon spp. available at GenBank and aligned to homologous sequences to perform the phylogenetic analysis. This analysis clearly showed that our sequence clustered, independently of H. americanum sequences, within a group comprising other Hepatozoon canis sequences. Our results confirmed the hypothesis that the agent causing hepatozoonosis in the areas studied in Brazil is H. canis, supporting previous reports that were based on morphological and morphometric analyses.