Limits...
Horizontal transmission and phylogenetic analysis of bovine leukemia virus in two districts of Miyazaki, Japan.

Mekata H, Sekiguchi S, Konnai S, Kirino Y, Horii Y, Norimine J - J. Vet. Med. Sci. (2015)

Bottom Line: Among genotype I, genetically distinct strains were spread at each farm, and cattle infected with less than 3 copies/100 cells did not transmit BLV to other cattle for more than thirty months.The data facilitate farmers and veterinarians understanding the status of BLV infected cattle.This research contributes to BLV infection control and the development of effective BLV eradication programs.

View Article: PubMed Central - PubMed

Affiliation: Project for Zoonoses Education and Research, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan.

ABSTRACT
Horizontal transmission is recognized as a major infection route for bovine leukemia virus (BLV), and cattle with high viral loads are considered to be a major infectious source in a herd. However, a correlation between viral loads and the risk of infection has been insufficient to use as a foundation for BLV control strategies. In this report, we examined the epidemiology of BLV infection and the infectious source in a local area. In 2013-2014, BLV infection was investigated in 1,823 cattle from 117 farms in two adjacent districts, Miyazaki, Japan. Seropositive samples for BLV were detected with 88 cattle and in 14 farms. Phylogenetic analysis revealed that 94% of the isolates clustered into genotype I and the remaining isolate into genotype III. Among genotype I, genetically distinct strains were spread at each farm, and cattle infected with less than 3 copies/100 cells did not transmit BLV to other cattle for more than thirty months. This is the first report of concrete data of viral load in relation to viral horizontal transmission under the field condition. The data facilitate farmers and veterinarians understanding the status of BLV infected cattle. This research contributes to BLV infection control and the development of effective BLV eradication programs.

No MeSH data available.


Related in: MedlinePlus

A phylogenetic tree analysis of BLV isolates based on full-length gp51env gene sequences and the viral loads in infected cattle. BLVisolates are represented by the IDs of the infected cattle and the affected farm.GenBank accession numbers of each isolate are listed in Table 2. The viral loads are given in parentheses. Thereference strains are represented by GenBank accession numbers, together with thecountry of isolation. Subgenotypes are indicated by Roman and Arabic numerals withunderline, and genotypes are indicated by Roman numeral [14]. Triangle shapes indicate the subgenotypes observed in only onecattle infected in this study. Out of 88 seropositive cattle, 11 were negative for PCRdetection and not included for phylogenic analysis. Horizontal branch lengths aredrawn to scale. Bootstrap support values (>80% in 1,000 replications) are shown forkey nodes only.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591153&req=5

fig_002: A phylogenetic tree analysis of BLV isolates based on full-length gp51env gene sequences and the viral loads in infected cattle. BLVisolates are represented by the IDs of the infected cattle and the affected farm.GenBank accession numbers of each isolate are listed in Table 2. The viral loads are given in parentheses. Thereference strains are represented by GenBank accession numbers, together with thecountry of isolation. Subgenotypes are indicated by Roman and Arabic numerals withunderline, and genotypes are indicated by Roman numeral [14]. Triangle shapes indicate the subgenotypes observed in only onecattle infected in this study. Out of 88 seropositive cattle, 11 were negative for PCRdetection and not included for phylogenic analysis. Horizontal branch lengths aredrawn to scale. Bootstrap support values (>80% in 1,000 replications) are shown forkey nodes only.

Mentions: Genotypes I and III were identified in this study, and genotype I accounted for 94% (17/18)of isolates. We classified genotype I into 17 subgenotypes depending on a phylogenetic treeanalysis (Fig. 2Fig. 2.


Horizontal transmission and phylogenetic analysis of bovine leukemia virus in two districts of Miyazaki, Japan.

Mekata H, Sekiguchi S, Konnai S, Kirino Y, Horii Y, Norimine J - J. Vet. Med. Sci. (2015)

A phylogenetic tree analysis of BLV isolates based on full-length gp51env gene sequences and the viral loads in infected cattle. BLVisolates are represented by the IDs of the infected cattle and the affected farm.GenBank accession numbers of each isolate are listed in Table 2. The viral loads are given in parentheses. Thereference strains are represented by GenBank accession numbers, together with thecountry of isolation. Subgenotypes are indicated by Roman and Arabic numerals withunderline, and genotypes are indicated by Roman numeral [14]. Triangle shapes indicate the subgenotypes observed in only onecattle infected in this study. Out of 88 seropositive cattle, 11 were negative for PCRdetection and not included for phylogenic analysis. Horizontal branch lengths aredrawn to scale. Bootstrap support values (>80% in 1,000 replications) are shown forkey nodes only.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591153&req=5

fig_002: A phylogenetic tree analysis of BLV isolates based on full-length gp51env gene sequences and the viral loads in infected cattle. BLVisolates are represented by the IDs of the infected cattle and the affected farm.GenBank accession numbers of each isolate are listed in Table 2. The viral loads are given in parentheses. Thereference strains are represented by GenBank accession numbers, together with thecountry of isolation. Subgenotypes are indicated by Roman and Arabic numerals withunderline, and genotypes are indicated by Roman numeral [14]. Triangle shapes indicate the subgenotypes observed in only onecattle infected in this study. Out of 88 seropositive cattle, 11 were negative for PCRdetection and not included for phylogenic analysis. Horizontal branch lengths aredrawn to scale. Bootstrap support values (>80% in 1,000 replications) are shown forkey nodes only.
Mentions: Genotypes I and III were identified in this study, and genotype I accounted for 94% (17/18)of isolates. We classified genotype I into 17 subgenotypes depending on a phylogenetic treeanalysis (Fig. 2Fig. 2.

Bottom Line: Among genotype I, genetically distinct strains were spread at each farm, and cattle infected with less than 3 copies/100 cells did not transmit BLV to other cattle for more than thirty months.The data facilitate farmers and veterinarians understanding the status of BLV infected cattle.This research contributes to BLV infection control and the development of effective BLV eradication programs.

View Article: PubMed Central - PubMed

Affiliation: Project for Zoonoses Education and Research, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan.

ABSTRACT
Horizontal transmission is recognized as a major infection route for bovine leukemia virus (BLV), and cattle with high viral loads are considered to be a major infectious source in a herd. However, a correlation between viral loads and the risk of infection has been insufficient to use as a foundation for BLV control strategies. In this report, we examined the epidemiology of BLV infection and the infectious source in a local area. In 2013-2014, BLV infection was investigated in 1,823 cattle from 117 farms in two adjacent districts, Miyazaki, Japan. Seropositive samples for BLV were detected with 88 cattle and in 14 farms. Phylogenetic analysis revealed that 94% of the isolates clustered into genotype I and the remaining isolate into genotype III. Among genotype I, genetically distinct strains were spread at each farm, and cattle infected with less than 3 copies/100 cells did not transmit BLV to other cattle for more than thirty months. This is the first report of concrete data of viral load in relation to viral horizontal transmission under the field condition. The data facilitate farmers and veterinarians understanding the status of BLV infected cattle. This research contributes to BLV infection control and the development of effective BLV eradication programs.

No MeSH data available.


Related in: MedlinePlus