RESUMO
Classical swine fever (CSF), caused by CSF virus (CSFV), is a highly contagious swine disease with high morbidity and mortality, which has caused significant economic losses to the pig industry worldwide. Biosecurity measures and vaccination are the main methods for prevention and control of CSF since no specific drug is available for the effective treatment of CSF. Although a series of biosecurity and vaccination strategies have been developed to curb the outbreak events, it is still difficult to eliminate CSF in CSF-endemic and re-emerging areas. Thus, in addition to implementing enhanced biosecurity measures and exploring more effective CSF vaccines, other strategies are also needed for effectively controlling CSF. Currently, more and more research about anti-CSFV strategies was carried out by scientists, because of the great prospects and value of anti-CSFV strategies in the prevention and control of CSF. Additionally, studies on anti-CSFV strategies could be used as a reference for other viruses in the Flaviviridae family, such as hepatitis C virus, dengue virus, and Zika virus. In this review, we aim to summarize the research on anti-CSFV strategies. In detail, host proteins affecting CSFV replication, drug candidates with anti-CSFV effects, and RNA interference (RNAi) targeting CSFV viral genes were mentioned and the possible mechanisms related to anti-CSFV effects were also summarized.
RESUMO
Senecavirus A (SVA), formerly known as Seneca Valley virus (SVV), causes vesicular symptoms in adult pigs and acute death of neonatal piglets. This pathogen has emerged in major swine producing countries around the world and caused significant economic losses to the pig industry. Thus, it is necessary to develop strategies to prevent and control SVA infection. Herein, an SVA strain (named GD-ZYY02-2018) was isolated from a pig herd with vesicular symptoms in Guangdong province of China in 2018. The present study aimed to carry out the phylogenetic analysis of the GD-ZYY02-2018 strain, determine its pathogenicity in finishing pigs, and assess the protective efficacy of the inactivated GD-ZYY02-2018 strain against virus challenge. The results of phylogenetic analysis showed that the SVA GD-ZYY02-2018 strain belonged to the USA-like strains and had a close genetic relationship with recent Chinese SVA strains. Animal challenge experiment showed that 100-day-old pigs inoculated intranasally with SVA GD-ZYY02-2018 strain developed vesicular lesion, low fever, viremia, and virus shedding in feces. The immunization challenge experiment showed that pigs vaccinated with inactivated GD-ZYY02-2018 strain could produce a high titer of anti-SVA neutralizing antibody and no vesicular lesion, fever, viremia, and virus shedding in feces was observed in vaccinated pigs after challenge with GD-ZYY02-2018 strain, indicating that inactivated GD-ZYY02-2018 could protect finishing pigs against the challenge of homologous virus. In conclusion, preliminary results indicated that inactivated GD-ZYY02-2018 could be used as a candidate vaccine for in-depth research and might be conducive to the prevention and control of SVA infection.
RESUMO
Heat stress has a negative impact on dairy cow productivity. In order to reveal the mechanisms of heat-stress response, the mRNA and miRNA expression profiles of five cows under chronic heat-stress and thermoneutral conditions were assayed in blood by high-throughput sequencing technology. A total of 540 mRNAs and 9 miRNAs were expressed differently under heat-stress and thermoneutral conditions. Functional analyses revealed that MAPK signaling pathway, cellular senescence, circadian entrainment, aldosterone synthesis and secretion, and pathways in cancer were enriched for differently expressed mRNAs; meanwhile cGMP-PKG signaling pathway, thermogenesis, and protein digestion and absorption were enriched for differently expressed miRNAs. In addition, GADD45G, TGFB2, and GNG11 may play roles in the heat stress, and bta-miR-423-5p might be one of the regulators of heat-stress response in cows as potential mediators of chronic heat-stress response. In conclusion, the present study described the mRNA and miRNA expression patterns in blood extracted from cows during the transition from heat-stress to thermoneutral conditions. The results provide new data that could help in identifying mechanisms that mediate cows' response to chronic heat stress.
