Characterization of the Fecal Microbiota of Pigs before and after Inoculation with “Brachyspira hampsonii”

“Brachyspira hampsonii” causes disease indistinguishable from swine dysentery, and the structure of the intestinal microbiome likely plays a role in determining susceptibility of individual pigs to infection and development of clinical disease. The objectives of the current study were to determine if the pre-inoculation fecal microbiota differed between inoculated pigs that did (INOC MH) or did not (INOC non-MH) develop mucohaemorrhagic diarrhea following challenge with “B. hampsonii”, and to quantify changes in the structure of the microbiome following development of clinical disease. Fecal microbiota profiles were generated based on amplification and sequencing of the cpn60 universal target sequence from 89 samples from 18 pigs collected at −8, −5, −3 and 0 days post-inoculation, and at termination. No significant differences in richness, diversity or taxonomic composition distinguished the pre-inoculation microbiomes of INOC MH and INOC non-MH pigs. However, the development of bloody diarrhea in inoculated pigs was associated with perturbation of the microbiota relative to INOC non-MH or sham-inoculated control pigs. Specifically, the fecal microbiota of INOC MH pigs was less dense (fewer total 16S rRNA copies per gram of feces), and had a lower Bacteroidetes:Firmicutes ratio. Further investigation of the potential long-term effects of Brachyspira disease on intestinal health and performance is warranted.     

Comparative Efficacy of Nucleoside Analogues Against African Swine Fever Virus “in Vitro”

Abstract

A comparative study on the “in vitro” activity of various nucleoside analogues has been carried out on the Lisbona 60 strain of ASFV adapted to VERO cells. β-D-xylofuranosyl-adenine and β-D-lyxofuranosyl-guanine emerged as the compounds endowed with the most favourable selectivity index.     

Inoculation of cyprinid herpesvirus 3 (CyHV-3) on common carp brain cells—influence of process parameters on virus yield

Research of cyprinid herpesvirus 3 (CyHV-3) is focused on the infection mechanism and disease development in animals using genetic and immunological approaches to improve treatments and diagnostics. In contrast, only few tried to investigate the CyHV-3 replication behaviour in available cell cultures. Whereas, obtaining high virus yields by in vitro replication enables achieving of the mentioned above goals easier and more reliable. The following work presents an attempt to illuminate the KHV replication in common carp brain (CCB) cell cultures from the engineering point of view. The isolate KHV-TP30 was used testing the influence on process parameters, such as multiplicity of infection (MOI), time of infection (TOI) and time of harvest (TOH). Virus concentrations and infectivity at different time points of infection were examined using hydrolyzed probe qPCR (Gilad et al. 2004) and 50% tissue culture infectivity dose (TCID₅₀). The data obtained show that while the amount of the virus DNA remains constant after reaching its maximum, the infectivity of the virus decreases. Thus, especially, TOH can be crucial for generating a high-quality virus stock. Applying optimized parameters improved the infectivity of the harvested virus and reached a robust titre as high as 1.9 × 10⁸ TCID₅₀/mL. To our knowledge, so far, there is no information in the peer-reviewed literature showing comparably high virus titres. Such virus yields not only facilitate conduction of further studies, including stability tests of the virus stock under various supplementation or disinfection trails, but also provide enough virus material to perform more detailed examinations of the infection mechanism.     

Synthesis of Branched Oligoribonucleotides (“Lariat”)

Abstract

Four different strategies for the synthesis of branched oligoribonucleotides, from trimers to heptamer, are described.     

The “sapucaia” group of Lecythis (Lecythidaceae)

Four previously much confused species of Lecythis, which form a coherent group of species collectively known in Brazil as “sapucaias,” are described and differentiated in a key. A summary of their pollination and dispersal is presented as well as of their present-day distributions in relation to past geological and climatological events. Fruit variability, the cause of name proliferation in this group, is described and related to the problem of species concepts in the Lecythidaceae.