BackgroundCaseous lymphadenitis (CL) is a contagious infectious disease of small ruminants caused by Corynebacterium pseudotuberculosis. Is characterized by the formation of abscesses in the lymph nodes and intestines of infected animals, induced by inflammatory cytokines. The production of cytokines, such as IL-10, TNF-α, IL-4 and IFN-γ, is regulated by mitogen-activated protein kinase (MAPK) pathway activation. The present study investigated the involvement of MAPK pathways (MAPK p38, ERK 1 and ERK 2) with respect to the production of cytokines induced by antigens secreted by C. pseudotuberculosis over a 60-day course of infection. CBA mice (n = 25) were divided into three groups and infected with 102 colony forming units (CFU) of attenuated strain T1, 102 CFU of virulent strain VD57 or sterile saline solution and euthanized after 30 or 60 days. Murine splenocytes were treated with specific inhibitors (MAPK p38 inhibitor, ERK 1/2 inhibitor or ERK 2 inhibitor) and cultured with secreted antigens obtained from pathogenic bacteria (SeT1 or SeVD57).ResultsThe MAPK pathways evaluated were observed to be involved in the production of IL-10, under stimulation by secreted antigens, while the MAPK p38 and ERK 1 pathways were shown to be primarily involved in TNF-α production. By contrast, no involvement of the MAPK p38 and ERK 1 and 2 pathways was observed in IFN-γ production, while the ERK 2 pathway demonstrated involvement in IL-4 production only in the mouse splenocytes infected with VD57 under stimulation by SeT1.ConclusionThe authors hypothesize that MAPK p38 and ERK 1 pathways with respect to TNF-α production, as well as the MAPK p38 and ERK 1 and 2 pathways in relation to IL-10 production under infection by C. pseudotuberculosis are important regulators of cellular response. Additionally, the lack of the MAPK p38 and ERK 1/2 pathways in IFN-γ production in infected CBA murine cells stimulated with the two secreted/excreted antigens, in IL-4 production showing involvement only via the ERK 2 pathway under stimulation by SeT1 antigen during 60-day infection period with the virulent strain, suggests that these pathways regulated the production of pro-inflammatory and regulatory cytokines in the splenic cells of CBA mice.

This paper describes the identification of an outbreak of fowlpox in backyard chickens in two villages the state of Bahia, the intervention strategy to control the disease by adopting health measures and vaccination, as well as the impact of the intervention. The diagnosis was based in clinical and laboratory data. After the diagnosis was confirmed, control measures and the vaccination of non-infected birds were recommended. Finally, the impact of the intervention on reincidence of the disease was evaluated. A number of 700 chickens was vaccinated, after which only 9% of the farmers reported the occurrence of new cases, and 70% informed the acquisition of new birds after vaccination. The information reported in this paper can be useful to design strategic plans to control fowlpox in backyard chickens.

RESUMO Estudos sorológicos em Avestruzes (Struthio camelus) são ferramentas úteis para analisar os riscos relacionados à Doença de

Este estudo teve como objetivo determinar a frequência de anticorpos contra o metapneumovírus aviário (AMPV) em criações, não vacinadas, de frangos de corte e galinhas de quintal no polo avícola do Estado da Bahia. Coletaram-se 622 amostras de soro de criações de frangos de corte e 268 amostras de galinhas de quintal. A sorologia foi realizada por meio do kit comercial de ELISA indireto. Na análise estatística utilizou-se o teste t de Student com intervalo de confiança de 95%. Detectaram-se aves soropositivas para o AMPV tanto nos frangos de corte (144; 23,15%) quanto nas galinhas de quintal (187; 69,78%) (p = 0,1). Os lotes de frangos de corte tiveram frequência de anticorpos contra o AMPV de 77,14% e as propriedades de aves caipiras de 94,12%. No grupo de frangos de corte evidenciaram-se anticorpos contra o vírus em 66,67% e 33,33% das aves com e sem sintomas respiratórios, respectivamente. Já nas aves caipiras foram encontradas frequências elevadas de soropositivas tanto nas aves com sintomas respiratórios (60,43%) quanto naquelas sem sintomas (39,57%). Os resultados demonstram que houve infecção pelo vírus nas criações de frangos de corte e de galinhas de quintal, sugerindo a presença do AMPV no polo avícola da Bahia. PALAVRAS-CHAVES: ELISA indireto, frangos de corte, galinhas de quintal, metapneumovírus aviário.