Molecular detection of bovine immunodeficiency virus in water buffaloes (Bubalus bubalis) from the Amazon region, Brazil

Abstract

Bovine immunodeficiency is a chronic progressive disease caused by a lentivirus that affects cattle and buffaloes. Although the infection has been described in cattle in some countries, including in Brazil, there are only two reports of infection in buffaloes: one in Pakistan and one in Cambodia. The aim of the present study was to survey the occurrence of bovine immunodeficiency virus (BIV) in water buffaloes from the Amazon region, Pará state, Brazil. BIV proviral DNA was surveyed in 607 whole blood samples of water buffaloes from 10 farms located in the state of Pará using semi-nested polymerase chain reaction (PCR) (PCR-SN) to amplify the pol region of the viral genome. Of the 607 samples tested, 27 (4.4 %) were positive for BIV proviral DNA. The amplified fragments were confirmed by sequence analysis after cloning and nucleotide sequencing. The sequence obtained had 99 % similarity to the reference strain (R-29). The present study provides important epidemiological data because BIV was detected for the first time in water buffaloes in Brazil. Further, the results suggest the possibility of the virus being a risk factor for herd health because it may be a potential causal agent of chronic disease and, also may be associated to other infectious diseases.

Molecular detection of bovine immunodeficiency virus (BIV) in bovines from the state of Minas Gerais, Brazil

“…These results, when compared to other studies done in the country, showed that the regions tested in the state of Minas Gerais presented a very similar occurrence of BIV infections found by serology and molecular methods in studies carried out in the states of Mato Grosso do Sul and Rio Grande of the South (Meas et al, 2002) and higher than the average found in buffalo in the state of Pará (4.4%) (Albernaz et al, 2015). This percentage was also higher than the values observed by direct detection through PCR in India (8.8%) and moderately similar to the serology studies conducted in Japan (11.7%) (Meas et al, 1998;Patil et al, 2003).…”

“…In Brazil, BIV has been detected in cattle from the states of Mato Grosso do Sul and Rio Grande do Sul using PCR and through the detection of antibodies to the capsid p26 protein by Western Blot (Meas et al, 2002). BIV was also detected using semi-nested PCR in peripheral blood leukocytes of buffaloes from the Amazon region (Albernaz et al, 2015).…”

“…All the extracted samples were submitted to a PCR for the detection of the glyceraldehyde 3phosphate dehydrogenase (GAPDH) normalizing bovine gene (Pinheiro de Oliveira et al, 2013). Detection of proviral DNA present in the field samples was conducted through the SN-PCR (Albernaz et al, 2015). As a positive control for SN-PCR, plasmid BIV127, kindly provided by Dr Charles Wood (Center for Virology, University of Nebraska-Lincoln), containing part of the pol gene was used.…”

“…Epidemiological studies on BIV are difficult to carry out due to the absence of a simple, fast and effective test, especially when the number of animals surveyed is high. In recent years, PCR has become a very important tool in the direct detection of pathogens including BIV, and because it is a rapid and highly sensitive method, it can detect a very small amount of DNA in a relatively short period of time (Orr et al, 2003).There are no previous studies reporting the presence of BIV in Minas Gerais, although the infection has been reported in bovines from Central West and Southern Brazil (Meas et al, 2002), besides buffaloes from the Amazon region of the country (Albernaz et al, 2015).…”

Identification of the membrane-spanning domain of glycoprotein 45 in bovine immunodeficiency virus

“…The BIV genome, similar to human immunodeficiency virus (HIV) and other lentiviruses, contains the structural genes gag, pol, env and several accessory genes tat, rev, vif, vpw, vpy, and tmx. However, although some studies on BIV are focused on tat (Guo et al, 2013), vif (Zhang et al, 2014) rev (Gomez Corredor and Archambault, 2009;Gomez Corredor and Archambault, 2012) and others (Albernaz et al, 2015;Liu et al, 2015), very scarce attention has been paid to env. The Env of BIV is composed of two subunits: gp100, a surface subunit (SU) that binds host cell receptors, and gp45, a transmembrane subunit (TM) that ultimately inserts into the host cell membrane and promotes the fusion.…”