RESUMEN
@#Porcine circovirus type 4 (PCV4) is the newest member in the porcine circovirus family, first reported in 2020. To date, the presence of PCV4 has only been reported in China, South Korea and most recently in Thailand. Detection of PCV4 have been reported in various production stages of pigs from piglets, finishers to sows; associated with a myriad of clinical manifestations including porcine dermatitis and nephropathy syndrome (PDNS), postweaning multisystemic wasting syndrome (PMWS), respiratory, enteric and neurological diseases. While successful virus isolation and culture has yet to be reported, pathogenicity of PCV4 has been demonstrated through infectious clone studies. The objective of this study is to investigate the presence of PCV4 in Malaysian porcine population to update the epidemiology of porcine circoviruses in Malaysia. A total of 49 samples from commercial intensive pig farms, abattoir and wild boar population were subjected to conventional polymerase chain reaction assay to detect PCV4 capsid (cap) genome. Resulting cap nucleotide sequences were analyzed for maximum likelihood phylogeny relationship. Results revealed that PCV4 is present in Peninsular Malaysia at a molecular prevalence of 4.08% (2 / 49 samples). Both PCV4 positive samples originated from clinically healthy finishers. Malaysian PCV4 strains were classified as genotype PCV4b, and were found to be phylogenetically distinct from the China, South Korea and Thailand strains. With this latest update of the novel PCV4 in Malaysia, it is clear that more attention needs to be given to the investigation of novel porcine circoviruses (PCV) and management of PCV diseases.
RESUMEN
Neste trabalho, foi estudada a ocorrência e a bacteriologia das otites purulentas em suínos apresentando três condições clínico-patológicas distintas: síndrome multissistêmica do definhamento dos suínos (SMDS), crescimento retardado (porém sem apresentação de sinais clínicos da SMDS) e crescimento normal. No total, foram examinados 385 animais com idade de 60-130 dias, sendo a confirmação do diagnóstico da SMDS obtida pelos sinais clínicos e achados patológicos e pela detecção de antígenos virais por imunoistoquímica. De 242 animais com a SMDS, 57 (23,5 por cento) apresentaram lesões purulentas no ouvido médio. Entre os 119 animais de baixo desenvolvimento, apenas 1 (0,7 por cento) apresentou a lesão. Não foram detectadas lesões macroscópicas no ouvido médio dos 24 animais com crescimento normal. Os agentes isolados com maior freqüência foram Arcanobacterium pyogenes (43 por cento), Streptococcus α-hemolíticos (37,2 por cento) e Pasteurella multocida (27,9 por cento) dos 86 ouvidos submetidos à bacteriologia. A alta ocorrência de lesões purulentas no ouvido médio de animais com a SMDS sugere que a infecção pelo PCV2 pode tornar o suíno mais suscetível às otites bacterianas. A ocorrência reduzida dessas lesões em suínos de baixo desenvolvimento, sem a manifestação clínica da SMDS, sugere que a otite média não representa uma causa importante de mau desempenho em leitões nas fases de crescimento e terminação. O envolvimento de A. pyogenes, Streptococcus α-hemolíticos e P. multocida na maioria das lesões apontam a importância desses organismos como agentes causais de otite média em suínos.(AU)
The occurrence and bacteriology of purulent otitis in groups of pigs affected by three different clinical conditions are described: postweaning multisystemic wasting syndrome (PMWS), depressed growth (attrition) and normal growth (control). A total of 385 animals, 60-130 days of age, were examined. Diagnosis of PMWS was confirmed by the presence of clinical signs and pathological findings compatible with the disease, and through detection of viral antigens in tissues by immunohistochemistry. From 242 pigs with PMWS, 57 (23.5 percent) showed purulent lesions in the middle ear. Among 119 pigs with attrition, only 1 (0.7 percent) presented the lesion. In 24 control pigs, middle ear lesions were not detected. The most frequently isolated agents from the lesions were Arcanobacterium pyogenes (43 percent), á-hemolytic Streptococci (37.2 percent) and Pasteurella multocida (27.9 percent) out of 86 materials. The frequent occurrence of purulent lesions in the middle ear of PMWS affected pigs suggests that PCV2 infection may increase the susceptibility to bacterial otitis. The low occurrence of this disease in piglets with attrition suggests that otitis does not represent a significant cause for depressed growth in pigs from growing and finishing age. The isolation of A. pyogenes, á-hemolytic Streptococci and P. multocida from most of the lesions emphasizes the importance of these organisms as causal agents of otitis media in swine.(AU)