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Peacock bass (syn.: tucunaré, Cichla ocellaris) and the pearl cichlids (syn.: acará, Geophagus brasiliensis) are South American cichlids that are highly valued in both the ornamental and sport fish industries. Since 2017, a number of outbreaks of infectious spleen and kidney necrosis virus (ISKNV) have been reported on Brazilian food and ornamental fish farms. In this study, we detected ISKNV in farmed peacock bass and pearl cichlid by PCR and sequence analysis of the partial major capsid protein (MCP) gene. Moribund peacock bass (n=10) and pearl cichlids (2) from a farm experiencing elevated mortality among juveniles and adults of these species, were submitted for bacteriological and molecular diagnostics. Spleen, liver, brain, and kidney tissues were cultured on 5% sheep blood agar and cystine heart agar with 1% glucose and bovine haemoglobin. No bacteria were isolated from the 12 fish. Additionally, DNA extracts from the liver and spleen of all animals were tested for ISKNV using two conventional polymerase chain reaction (cPCR) assays and two nested PCR (nPCR) assays. ISKNV DNA was amplified in all 12 fish DNA extracts tested, in two or more of the PCR assays. Selected ISKNV amplicons were confirmed by Sanger sequencing. The nucleotide sequences derived from these animals were identical to ISKNV strains previously detected in food (e.g., tilapia and carp) and ornamental species, including strains previously detected in fish from Brazil. To the authors’ knowledge, this is the first report of ISKNV in these native Brazilian cichlids.

Bovine gammaherpesvirus 6 (BoGHV6), formerly known as bovine lymphotropic virus, belongs to the genus Macavirus, which includes the porcine lymphotropic herpesviruses (PLHV) and members collectively referred to as malignant catarrhal fever virus (MVFV) group. This study investigated the possible participation of BoGHV6 in the development of intestinal and pulmonary diseases of buffaloes. Intestinal and pulmonary fragments were obtained from 19 buffaloes from Goiás, Central-western Brazil. Histopathology revealed interstitial pneumonia in all pulmonary fragments evaluated, while two of these had suppurative bronchopneumonia. Furthermore, all intestinal fragments demonstrated atrophic enteritis. BoGHV6 DNA was amplified from 31.6% (6/19) of the buffaloes with interstitial pneumonia and in 26.3% (5/19) with atrophic enteritis. The phylogenetic evaluation revealed that the strain of BoGHV6 amplified from these buffaloes had 100% nucleotide (nt) sequence identity with the reference strains of BoGHV6, but only 69.5 to 73.7% and 65.8 – 69.5% nt sequence identity with members of the MCFV and the PLHV, respectively. Additionally, molecular assays to detect important pathogens of ruminants did not amplify the respective nucleic acids in the tissues evaluated. These results demonstrated that BoGHV6 was amplified from tissues of buffaloes with histopathologic diagnoses of interstitial pneumonia and atrophic enteritis, suggesting the possible participation of this virus in the development of the intestinal and pulmonary lesions herein identified.

This study aimed to determine the antimicrobial susceptibility profile and to assess the presence of mechanisms of antimicrobial resistance in Staphylococcus spp. (n=36) isolated from mastitis in sheep’s Chapecó-SC. The potential for biofilm production was determined by phenotypic tests of Congo Red Agar, DAPI and Gentian Violet and by PCR for the detection of icaD gene. To evaluate the antimicrobial resistance testing was performed disk diffusion and detection of resistance genes blaZ, mecA, ermA, ermB and ermC and msrA also performed by PCR.The pump test was conducted by efuxo crop growth Muller Hinton agar containing ethidium bromide. The results showed that 1 (2,78%), 36 (100%) and 10 (27,78%) isolates were considered to produce a biofilm on Congo Red Agar test, Gentian Violet and DAPI, respectively, while the gene icaD was observed in only 2 (5.55%) isolates. The lowest percentage of sensitivity was observed for ampicillin (58.33%) and penicillin (58.33%). All strains tested were negative for the mecA, ermA, ermB and ermC genes. However, the isolates were positive for other resistance genes, being the blaZ and the msrA, with percentages of positivity of 58.33% and 11.11% respectively. Only one sample was positive for efflux pump test.O presente trabalho teve como objetivos determinar o perfil de sensibilidade aos antimicrobianos e avaliar a presença de mecanismos de resistência antimicrobiana em Staphylococcus spp. (n=36) isolados de mastite em ovelhas do município de Chapecó-SC. O potencial para produção de biofilme foi determinado pelos testes fenotípicos de Agar Vermelho Congo, DAPI e Violeta de Genciana e por teste molecular pela técnica de PCR para a detecção do gene icaD. Para determinar o perfil de resistência aos antimicrobianos, foi realizado o teste de difusão em disco e detecção dos genes de resistência blaZ, mecA, erm (A, B e C) e msrA. O teste da bomba de efuxo foi realizado através do crescimento das culturas em Agar Muller Hinton contendo brometo de etídio. Os resultados mostraram que 1 (2,78%), 36 (100%) e 10 (27,78%) isolados foram considerados produtores de biofilme pelos testes de Agar Vermelho Congo, DAPI e Violeta de Genciana, respectivamente, enquanto que o gene icaD foi observado em apenas 2 (5,55%) isolados. O menor percentual de sensibilidade foi observado para ampicilina (58,33%) e penicilina (58,33%). Os isolados avaliados foram positivos para os genes de resistência blaZ (58,33%) e msrA (11,11%). Nenhum isolado apresentou os genes de resistência erm (A, B, C) e apenas uma amostra foi positiva para o teste da bomba de efluxo.