Masataka Akagami's research while affiliated with National Institute of Animal Health and other places

... Although almost all BLV-infected animals remain clinically asymptomatic throughout their lifespan, less than 5% of the infected cattle develop EBL [2]. Due to the lengthy latency period required by BLV, EBL is commonly seen in cattle older than 3 years [3], while onset of EBL in cattle under 3 years old has also been observed in Japan [4][5][6]. Although some factors related to onset of EBL in young cattle have been reported [6][7][8], the mechanism of early EBL onset is not fully understood. ...

... The tax and AS1-S genes were obtained from the BLV genome derived from FLK-BLV cells. The tax gene was amplified from a plasmid into which the BLV genome had been inserted (BLV infectious clone) in an earlier study [17], using PrimeSTAR Max DNA Polymerase (TaKaRa). The PCR conditions were as follows: 35 cycles of 98°C for 10 s, 55°C for 5 s, and 72°C for 1 min. ...

... Therefore, natural candidates for milk serological testing are dairy cattle and dairy small ruminants. Whilst in dairy cattle this approach has been intensively developed and widely applied in routine veterinary practice both at individual-and bulk tank milk-level (Akagami et al., 2020;Evermann et al., 2019), milk serological testing is relatively rarely used in dairy goat veterinary practice. To date, only one commercial ELISA for SRLV infection has been officially approved for diagnostic use on individual milk samples (ID Screen® MVV-CAEV Indirect Screening test, ID.vet Innovative Diagnostics, France), and another one is approved for research use only (Elitest MVV/CAEV ELISA, MV Diagnostics Ltd., UK). ...

... In Japan, chronic infectious diseases of cattle causing low productivity, such as enzootic bovine leukosis (EBL) and bovine viral diarrhea (BVD), endemically occur each year (24). Transmission of EBL and BVD is mainly caused by cohabitation with infected cattle, and thus the introduction of cattle from other farms has been reported as a risk factor for disease introduction (25,26). For example, summer grazing has been reported to be an important risk factor for the transmission of BVD (26,27). ...

... These are porcine stool-associated RNA viruses with a positive-sense single-stranded RNA genome [54]. They have been reported in swine populations in various age groups causing diarrhoea; however, infections may also be subclinical [55][56][57]. ...

... mo apart requirement for the determination of PL, using a reference value of 7500 cells/mL in accordance with reference values for second and third pregnancy cows(1,(32)(33)(34)(35)(36). ...

... phylogenetic analysis of a partial VP1 gene sequence has been used for classification of PSV isolates [21]. Due to the absence of classification criteria, PSV have long been contained only one genotype PSV-1 [42]. In contrast, novel PSV strains (SZ1M-F and EF9-F) were recently described in Hungary. ...

... The genome of porcine enterovirus G detected in feces of diarrheal pigs in farms of China, South Korea, Japan, United States, and Belgium was demonstrated inserting with a gene encoding a papain-like cysteine protease of ToV at the junction site of 2C and 3A genes (Conceição-Neto et al., 2017; 1 https://talk.ictvonline.org/taxonomy/ Knutson et al., 2017;Shang et al., 2017;Tsuchiaka et al., 2018;Wang et al., 2018;Lee and Lee, 2019). ...

... They all share a common genome organization, with a length of 8. 2-8.4 kb. The genome consists of a 5 ′ untranslated region (UTR), a single open reading frame (ORF) that encodes a large polyprotein of 2,400-2,500 amino acids which is divided into a leader (L) protein, three structural proteins (VP0, VP3, and VP1), seven non-structural proteins (2A−2C and 3A−3D), a 3 ′ UTR, and a poly(A) tail (2). Of these, the VP1 protein is the most variable, whereas the 3D gene is highly conserved (3). ...

... Recombination events of AstVs inter-or intragenotypic have been increasingly reported in recent years, which is the major mechanism contributing to the emergence of novel AstV lineages (7,12,13,30). In this study, intragenotypic recombination events were predicted in five of 19 strains in the Caprine Astrovirus G3.1 genotype (Fig. 2a to d), which was in accordance with previous reports on the intragenotypic recombination between BoAstVs (8) and between porcine AstVs (PoAstVs) (31). Interestingly, five recombination events occurred in different regions of ORF2, which can diversify viral capsid proteins, thus affecting the antigenicity of the virus and enabling it to escape host immunity (8,32). ...