The atypical porcine pestivirus (APPV) belongs to the species Pestivirus K of the genus Pestivirus and the family Flaviviridae, and it has been associated with congenital tremor (CT) type A-II in newborn piglets. Although APPV was discovered in 2015, evidence shows that APPV has circulated in pig herds for many years, at least since 1986. Due to the frequently reported outbreaks of CT on different continents, the importance of this virus for global pig production is notable. Since 2015, several studies have been conducted to clarify the association between APPV and CT. However, some findings regarding APPV infection and the measures taken to control and prevent the spread of this virus need to be contextualized to understand the infection better. This review attempts to highlight advances in the understanding of APPV associated with type A-II CT, such as etiology, epidemiology, diagnosis, and control and prevention measures, and also describes the pathophysiology of the infection and its consequences for pig production. Further research still needs to be conducted to elucidate the host’s immune response to APPV infection, the control and prevention of this infection, and the possible development of vaccines.

Bovine gammaherpesvirus 6 (BoGHV6), previously known as bovine lymphotropic virus, is a member of the Macavirus genus, subfamily Gammaherpesvirinae. Other members of the genus Macavirus include viruses that produce malignant catarrhal fever (MCF) in mammalian hosts, collectively referred to as the MCF virus (MCFV) complex, and the porcine lymphotropic herpesvirus (PLHV). However, the current role of BoGHV6 in the development of diseases and/or disease syndromes remains uncertain and controversial. This paper investigated the participation of BoGHV6 in the development of pulmonary disease in a cow with interstitial pneumonia by histopathology and molecular testing. Tissue antigens of common viral agents of respiratory diseases and Mycoplasma bovis were not identified by immunohistochemistry. Additionally, molecular assays designed to amplify common bacterial and viral pathogens of pulmonary disease did not amplify the nucleic acids of these agents. However, a pan-PCR assay amplified the DNA of the herpesvirus polymerase gene, while the specific BoGHV6 nested-PCR assay amplified the partial fragment of the BoGHV6 polymerase gene derived from the pulmonary tissue with interstitial pneumonia. Phylogenetic analysis revealed that the BoGHV6 strain herein identified had 99.8% nucleotide (nt) sequence identity with reference strains of BoGHV6, but only 72.2–73.5% and 67.9–68.6% nt identity with reference strains of MCFV and PLHV, respectively. Consequently, these results suggest that BoGHV6 was associated with the pulmonary disease observed in this cow.

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. Tucunaré (Cichla ocellaris) e acará (Geophagus brasiliensis) são ciclídeos sul-americanos muito valorizados tanto na indústria de peixes ornamentais como esportivos. Desde 2017, vários surtos do vírus da necrose infecciosa do baço e do rim (ISKNV) foram relatados em produções brasileiras de peixes de espécies alimentares e ornamentais. Neste estudo, relata-se a detecção de ISKNV em tucunarés e acarás cultivados por PCR e análise de sequência parcial do gene principal proteína do capsídeo (major capsid protein - MCP). Tucunarés (n=10) e acarás (2) moribundos provenientes de uma piscicultura com elevada mortalidade entre juvenis e adultos dessas espécies, foram submetidos ao diagnóstico bacteriológicas e molecular. Os tecidos do baço, fígado, cérebro e rim foram semeados em ágar sangue de carneiro a 5% e ágar cistina coração com 1% de glicose e hemoglobina bovina. Nenhuma bactéria foi isolada dos 12 peixes. Além disso, o DNA extraído do fígado e baço de todos os animais foram testados para ISKNV usando dois ensaios convencionais de reação em cadeia da polimerase (cPCR) e dois ensaios de nested PCR (nPCR). O DNA de ISKNV foi amplificado em todos os 12 extraídos de DNA dos peixes testados, em dois ou mais ensaios de PCR. Os amplicons de ISKNV selecionados foram confirmados pelo sequenciamento Sanger. As sequências de nucleotídeos derivadas desses animais eram idênticas às cepas de ISKNV previamente detectadas em espécies alimentares (ex. tilápias e carpas) e espécies ornamentais, incluindo cepas previamente detectadas em peixes do Brasil. Acredita-se que este é o primeiro relato de ISKNV nesses ciclídeos nativos brasileiros.