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Kohara J, Bai L, Takeshima SN, Matsumoto Y, Hirai T, Aida Y. Correlation between the Biodistribution of Bovine Leukemia Virus in the Organs and the Proviral Load in the Peripheral Blood during Early Stages of Experimentally Infected Cattle. Pathogens 2023; 12:130. [PMID: 36678478 PMCID: PMC9867250 DOI: 10.3390/pathogens12010130] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/27/2022] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis. However, the propagation and distribution of BLV after primary infection still need to be fully elucidated. Here, we experimentally infected seven cattle with BLV and analyzed the BLV proviral load (PVL) in the blood and various organs. BLV was first detected in the blood of the cattle after one week, and the blood PVL increased for three weeks after infection. The PVL was maintained at a high level in five cattle, while it decreased to a low or medium level in two cattle. BLV was distributed in various organs, such as the heart, lung, liver, kidney, abomasum, and thymus, and, notably, in the spleen and lymph nodes. In cattle with a high blood PVL, BLV was detected in organs other than the spleen and lymph nodes, whereas in those with a low blood PVL, BLV was only detected in the spleen and lymph nodes. The amount of BLV in the organs was comparable to that in the blood. Our findings point to the possibility of estimating the distribution of BLV provirus in organs, lymph nodes, and body fluids by measuring the blood PVL, as it was positively correlated with the biodistribution of BLV provirus in the body of BLV infection during early stages.
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Affiliation(s)
- Junko Kohara
- Animal Health Group, Animal Research Center, Hokkaido Research Organization, Shintoku 081-0038, Japan
| | - Lanlan Bai
- Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan
- Graduate School of Science and Engineering, Iwate University, Morioka 020-8551, Japan
| | - Shin-nosuke Takeshima
- Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan
- Department of Food and Nutrition, Jumonji University, 2-1-28 Sugasawa, Niiza 352-8510, Japan
| | - Yuki Matsumoto
- Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan
| | - Tsunao Hirai
- Animal Health Group, Animal Research Center, Hokkaido Research Organization, Shintoku 081-0038, Japan
| | - Yoko Aida
- Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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2
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Yang Y, Gong Z, Lu Y, Lu X, Zhang J, Meng Y, Peng Y, Chu S, Cao W, Hao X, Sun J, Wang H, Qin A, Wang C, Shang S, Yang Z. Dairy Cows Experimentally Infected With Bovine Leukemia Virus Showed an Increased Milk Production in Lactation Numbers 3–4: A 4-Year Longitudinal Study. Front Microbiol 2022; 13:946463. [PMID: 35898913 PMCID: PMC9309534 DOI: 10.3389/fmicb.2022.946463] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/20/2022] [Indexed: 11/29/2022] Open
Abstract
Bovine leukemia virus (BLV) is widespread in global cattle populations, but the effects of its infection on milk quantity and quality have not been clearly elucidated in animal models. In this study, 30 healthy first-lactation cows were selected from ≈2,988 cows in a BLV-free farm with the same criteria of parity, age, lactation number, as well as milk yield, SCS, and composition (fat, protein, and lactose). Subsequently, these cows were randomly assigned to the intervention (n = 15) or control (n = 15) group, and reared in different cowsheds. Cows in the intervention group were inoculated with 1 × phosphate-buffered solution (PBS) resuspended in peripheral blood mononuclear cells (PBMC) from a BLV-positive cow, while the controls were inoculated with the inactivated PBMC from the same individual. From June 2016 to July 2021, milk weight (kg) was automatically recorded by milk sensors, and milk SCS and composition were originated from monthly performed dairy herd improvement (DHI) testing. Fluorescence resonance energy transfer (FRET)–qPCR and ELISA showed that cows in the intervention group were successfully infected with BLV, while cows in the control group were free of BLV for the entire period. At 45 days post-inoculation (DPI), the numbers of whole blood cells (WBCs) (P = 0.010), lymphocytes (LYMs) (P = 0.002), and monocytes (MNCs) (P = 0.001) and the expression levels of IFN-γ (P = 0.013), IL-10 (P = 0.031), and IL-12p70 (P = 0.008) increased significantly in the BLV infected cows compared to the non-infected. In lactation numbers 2–4, the intervention group had significantly higher overall milk yield (P < 0.001), fat (P = 0.031), and protein (P = 0.050) than the control group, while milk SCS (P = 0.038) and lactose (P = 0.036) decreased significantly. Further analysis indicated that BLV infection was associated with increased milk yield at each lactation stage in lactation numbers 3–4 (P = 0.021 or P < 0.001), but not with SCS and milk composition. Together, this 4-year longitudinal study revealed that artificial inoculation of BLV increased the milk yield in cows in this BLV challenge model.
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Affiliation(s)
- Yi Yang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
- *Correspondence: Yi Yang
| | - Zaicheng Gong
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Yi Lu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Xubin Lu
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Jilei Zhang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ye Meng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Yalan Peng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Shuangfeng Chu
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Wenqiang Cao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Xiaoli Hao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Jie Sun
- Shenzhen Academy of Inspection and Quarantine Sciences, Shenzhen, China
| | - Heng Wang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Aijian Qin
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
| | - Chengming Wang
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Shaobin Shang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- International Corporation Laboratory of Agriculture and Agricultural Products Safety, Yangzhou University, Yangzhou, China
- Shaobin Shang
| | - Zhangping Yang
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
- Zhangping Yang
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Marawan MA, Alouffi A, El Tokhy S, Badawy S, Shirani I, Dawood A, Guo A, Almutairi MM, Alshammari FA, Selim A. Bovine Leukaemia Virus: Current Epidemiological Circumstance and Future Prospective. Viruses 2021; 13:v13112167. [PMID: 34834973 PMCID: PMC8618541 DOI: 10.3390/v13112167] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/23/2021] [Accepted: 10/24/2021] [Indexed: 11/23/2022] Open
Abstract
Bovine leukaemia virus (BLV) is a deltaretrovirus that is closely related to human T-cell leukaemia virus types 1 and 2 (HTLV-1 and -2). It causes enzootic bovine leukosis (EBL), which is the most important neoplastic disease in cattle. Most BLV-infected cattle are asymptomatic, which potentiates extremely high shedding rates of the virus in many cattle populations. Approximately 30% of them show persistent lymphocytosis that has various clinical outcomes; only a small proportion of animals (less than 5%) exhibit signs of EBL. BLV causes major economic losses in the cattle industry, especially in dairy farms. Direct costs are due to a decrease in animal productivity and in cow longevity; indirect costs are caused by restrictions that are placed on the import of animals and animal products from infected areas. Most European regions have implemented an efficient eradication programme, yet BLV prevalence remains high worldwide. Control of the disease is not feasible because there is no effective vaccine against it. Therefore, detection and early diagnosis of the disease are essential in order to diminish its spreading and the economic losses it causes. This review comprises an overview of bovine leukosis, which highlights the epidemiology of the disease, diagnostic tests that are used and effective control strategies.
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Affiliation(s)
- Marawan A. Marawan
- The State Key Laboratory of Agricultural Microbiology, Huazhong Agriculture University, Wuhan 430070, China; (I.S.); (A.D.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Benha University, Toukh 13736, Egypt;
- Correspondence: (M.A.M.); (A.G.); (A.S.)
| | - Abdulaziz Alouffi
- King Abdulaziz City for Science and Technology, Riyadh 12354, Saudi Arabia;
- The Chair of Vaccines Research for Infectious Diseases, King Saud University, Riyadh 11495, Saudi Arabia;
| | - Suleiman El Tokhy
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Tanta University, Tanta 31111, Egypt;
| | - Sara Badawy
- Department of Pathology, Faculty of Veterinary Medicine, Benha University, Toukh 13736, Egypt;
- Natural Reference Laboratory of Veterinary Drug Residues (HZAU), MAO Key Laboratory for Detection of Veterinary Drug Residues Huazhong Agricultural University, Wuhan 430070, China
| | - Ihsanullah Shirani
- The State Key Laboratory of Agricultural Microbiology, Huazhong Agriculture University, Wuhan 430070, China; (I.S.); (A.D.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Para-Clinic Department, Faculty of Veterinary Medicine, Jalalabad 2601, Afghanistan
| | - Ali Dawood
- The State Key Laboratory of Agricultural Microbiology, Huazhong Agriculture University, Wuhan 430070, China; (I.S.); (A.D.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Infectious Diseases, Medicine Department, Faculty of Veterinary Medicine, University of Sadat City, Sadat City 32897, Egypt
| | - Aizhen Guo
- The State Key Laboratory of Agricultural Microbiology, Huazhong Agriculture University, Wuhan 430070, China; (I.S.); (A.D.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China
- Correspondence: (M.A.M.); (A.G.); (A.S.)
| | - Mashal M. Almutairi
- The Chair of Vaccines Research for Infectious Diseases, King Saud University, Riyadh 11495, Saudi Arabia;
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 22334, Saudi Arabia
| | - Fahdah Ayed Alshammari
- College of Sciences and Literature Microbiology, Nothern Border University, Arar 73211, Saudi Arabia;
| | - Abdelfattah Selim
- Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Benha University, Toukh 13736, Egypt;
- Correspondence: (M.A.M.); (A.G.); (A.S.)
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Fonseca Júnior AA, Ferreira LR, Laguardia-Nascimento M, Rivetti Júnior AV, Bueno BL, Dos Reis JKP, Camargos MF. Evaluation of three different genomic regions for detection of bovine leukemia virus by real-time PCR. Braz J Microbiol 2021; 52:2483-2488. [PMID: 34595727 DOI: 10.1007/s42770-021-00613-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 09/19/2021] [Indexed: 11/26/2022] Open
Abstract
Bovine leukemia virus (BLV) is an oncogenic member of the genus Deltaretrovirus. BLV infects cattle worldwide and is responsible for significant economic losses. The objective of this study was to validate real-time quantitative PCR (qPCR) for the detection of BLV. After identification of the most efficient qPCR, the limits of detection, repeatability, and reproducibility were determined. The results indicate that qPCR can be easily reproduced between laboratories with high sensitivity. The test variation was low in samples from lesions suggestive of bovine leukosis or whole blood.
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Affiliation(s)
- Antônio Augusto Fonseca Júnior
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Avenida Rômulo Joviano, Centro, Pedro Leopoldo, Minas Gerais, 33600-000, Brazil.
- Centro Universitário de Sete Lagoas, UNIFEMM, Sete Lagoas, Brazil.
| | - Luciana Rabello Ferreira
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Avenida Rômulo Joviano, Centro, Pedro Leopoldo, Minas Gerais, 33600-000, Brazil
| | - Mateus Laguardia-Nascimento
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Avenida Rômulo Joviano, Centro, Pedro Leopoldo, Minas Gerais, 33600-000, Brazil
| | - Anselmo Vasconcelos Rivetti Júnior
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Avenida Rômulo Joviano, Centro, Pedro Leopoldo, Minas Gerais, 33600-000, Brazil
| | | | | | - Marcelo Fernandes Camargos
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Avenida Rômulo Joviano, Centro, Pedro Leopoldo, Minas Gerais, 33600-000, Brazil
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Bartlett PC, Ruggiero VJ, Hutchinson HC, Droscha CJ, Norby B, Sporer KRB, Taxis TM. Current Developments in the Epidemiology and Control of Enzootic Bovine Leukosis as Caused by Bovine Leukemia Virus. Pathogens 2020; 9:E1058. [PMID: 33352855 PMCID: PMC7766781 DOI: 10.3390/pathogens9121058] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 01/29/2023] Open
Abstract
Enzootic Bovine Leukosis (EBL) caused by the bovine leukemia virus (BLV) has been eradicated in over 20 countries. In contrast, the U.S. and many other nations are experiencing increasing prevalence in the absence of efforts to control transmission. Recent studies have shown that BLV infection in dairy cattle has a greater impact beyond the long-recognized lymphoma development that occurs in <5% of infected cattle. Like other retroviruses, BLV appears to cause multiple immune system disruptions, affecting both cellular and humoral immunity, which are likely responsible for increasingly documented associations with decreased dairy production and decreased productive lifespan. Realization of these economic losses has increased interest in controlling BLV using technology that was unavailable decades ago, when many nations eradicated BLV via traditional antibody testing and slaughter methods. This traditional control is not economically feasible for many nations where the average herd antibody prevalence is rapidly approaching 50%. The ELISA screening of cattle with follow-up testing via qPCR for proviral load helps prioritize the most infectious cattle for segregation or culling. The efficacy of this approach has been demonstrated in at least four herds. Breeding cattle for resistance to BLV disease progression also appears to hold promise, and several laboratories are working on BLV vaccines. There are many research priorities for a wide variety of disciplines, especially including the need to investigate the reports linking BLV and human breast cancer.
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Affiliation(s)
- Paul C. Bartlett
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (V.J.R.); (B.N.)
| | - Vickie J. Ruggiero
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (V.J.R.); (B.N.)
| | | | - Casey J. Droscha
- CentralStar Cooperative, East Lansing, MI 48910, USA; (C.J.D.); (K.R.B.S.)
| | - Bo Norby
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (V.J.R.); (B.N.)
| | - Kelly R. B. Sporer
- CentralStar Cooperative, East Lansing, MI 48910, USA; (C.J.D.); (K.R.B.S.)
| | - Tasia M. Taxis
- Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA;
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6
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Bovine leukemia virus detection and dynamics following experimental inoculation. Res Vet Sci 2020; 133:269-275. [PMID: 33039878 DOI: 10.1016/j.rvsc.2020.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/27/2020] [Accepted: 09/21/2020] [Indexed: 12/13/2022]
Abstract
Bovine leukemia virus (BLV) infects more than 40% of the United States cattle population and impacts animal health and production. Control programs aiming to reduce disease prevalence and incidence depend on the ability to detect the BLV provirus, anti-BLV antibodies, and differences in blood lymphocyte counts following infection. These disease parameters also can be indicative of long-term disease progression. The objectives of this study were to determine the timing and to describe early fluctuations of BLV-detection by qPCR, ELISA, and lymphocyte counts. Fifteen Holstein steers were experimentally inoculated with 100 μL of a blood saline inoculum. Three steers served as in-pen negative controls and were housed with the experimentally infected steers to observe the potential for contract transmission. Five additional negative controls were housed separately. Steers were followed for 147 days post-inoculation (DPI). Infections were detected in experimentally infected steers by qPCR and ELISA an average of 24- and 36 DPI, respectively. Significant differences in lymphocyte counts between experimentally infected and control steers were observed from 30 to 45 DPI. Furthermore, a wide variation in peak proviral load and establishment was observed between experimentally infected steers. The results of this study can be used to inform control programs focused on the detection and removal of infectious cattle.
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7
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Korniienko LY, Pyskun AV, Tsarenko TM, Ukhovskyi VV, Kyivska GV, Moroz OA, Kovalenko VL, Aliekseieva GB. Retrospective analysis of the epizootic situation of enzootic bovine leukosis in Ukraine in 1994–2019. REGULATORY MECHANISMS IN BIOSYSTEMS 2020. [DOI: 10.15421/022057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
In Ukraine, prevention and control measures of bovine leukosis were regulated by relevant legislation, regulations and instructions developed in the period 1960–1992. Currently, the instruction on prevention and rehabilitation of this disease in cattle is used (approved in 2007). According to it, the identification of infected animals is carried out from 6 months of age by serological (first scheme in AGID or another in ELISA) and genomic (PCR) methods. The infected animals are removed from the herd or slaughtered. In general, because of the diagnostic and preventive measures carried out during the analyzed period (26 years) 10 519 farms were rehabilitated from leukosis (2 346 affected farms remained from previous years). At the same time, more 4 million infected cattle were slaughtered. The majority of affected farms (more than 1 000) were registered in the period between 1994 (2 346 farms) and 2003 (1 247 farms). Since 2014, the number of affected farms has remained mostly below 10 and the number of infected cattle has decreased to 2 000 animals per year. At the same time, the number of rehabilitated farms also decreased (from 1 307 farms in 1998 to 4 farms in 2014). The same trend was registered with the dynamics of the number of animals that were removed from the herd due to leukosis. Thus, in 1995 and 1997 their numbers were 321 178 and 558 649 animals, respectively, and in 2014 it was 1 124. The obtained indicators of intensity and extensiveness of the epizootic process show that the incidence rate was maximal during 1998–2000 and amounted to 3.7–4.3%. The maximum indicators of the coefficient of affection were recorded in 1997–2000 and equal 11.8–15.3%. The rate of foci remained on the level of 90–270 throughout the all analyzed period. During 2008–2019, specialists of the Ukrainian veterinary laboratories investigated more than 47 million samples of cattle blood sera for enzootic bovine leukosis by AGID and ELISA. However, despite the significant diagnostic work, the important factor in the decrease of the number of affected farms and infected animals is the decrease in the total number of cattle in Ukraine (almost 22 million animals in 1994 against 3 million in 2019). Graphic trends of these indicators are comparable and agree with the decrease in the number of cattle in our country by analyzed period. After 2014, the number of affected farms ranged 10–17 per year (mostly in private households). However, the full recovery of cattle in Ukraine from bovine leukosis has not taken place, although our country is closer than ever to this.
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Ruggiero VJ, Norby B, Benitez OJ, Hutchinson H, Sporer KRB, Droscha C, Swenson CL, Bartlett PC. Controlling bovine leukemia virus in dairy herds by identifying and removing cows with the highest proviral load and lymphocyte counts. J Dairy Sci 2019; 102:9165-9175. [PMID: 31378496 DOI: 10.3168/jds.2018-16186] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 06/05/2019] [Indexed: 01/30/2023]
Abstract
The objective of this field trial was to reduce bovine leukemia virus (BLV) transmission and prevalence in commercial dairy herds using proviral load (PVL) and lymphocyte count (LC) measurements as indicators of the most infectious animals for culling or segregation. Bovine leukemia virus causes lymphoma in <5% of infected cattle, and increased lymphocyte counts (lymphocytosis) in about one-third. Recent research has shown that dairy cows infected with BLV have altered immune function associated with decreases in milk production and lifespan. Recent findings show that a minority of infected cattle have PVL concentrations in blood and other body fluids of over 1,000 times that of other infected cattle. In combination with a high LC, these animals are thought to be responsible for most transmission of BLV in a herd. Milk or blood samples from adult cows in our 3 Midwestern dairy farm field trials were tested semiannually with ELISA for BLV antibodies, and ELISA-positive cattle were then retested using a blood LC and a quantitative PCR test for PVL to identify the animals presumed to be most infectious. Herd managers were encouraged to consider PVL and LC status when making cull decisions, and to segregate cows with the highest PVL and LC from their BLV ELISA-negative herd mates where possible. After 2 to 2.5 yr of this intervention, the incidence risk of new infections decreased in all 3 herds combined, from 13.8 to 2.2, and the overall herd prevalence decreased in all 3 herds combined from 62.0 to 20.7%, suggesting that this approach can efficiently reduce BLV transmission as well as prevalence. This is encouraging, because a very low prevalence of BLV infection would make it economically feasible to cull the remaining ELISA-positive cattle, as was achieved in national eradication programs in other countries decades ago.
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Affiliation(s)
- V J Ruggiero
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824.
| | - B Norby
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824
| | - O J Benitez
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824
| | - H Hutchinson
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824
| | - K R B Sporer
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824; NorthStar Cooperative, Lansing, MI 48910
| | - C Droscha
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824; NorthStar Cooperative, Lansing, MI 48910
| | - C L Swenson
- Department of Pathobiology and Diagnostic Investigation and Veterinary Diagnostic Laboratory, Michigan State University, East Lansing 48824
| | - P C Bartlett
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824
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9
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Ruggiero VJ, Bartlett PC. Control of Bovine Leukemia Virus in Three US Dairy Herds by Culling ELISA-Positive Cows. Vet Med Int 2019; 2019:3202184. [PMID: 31341609 PMCID: PMC6614971 DOI: 10.1155/2019/3202184] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 06/03/2019] [Accepted: 06/10/2019] [Indexed: 01/12/2023] Open
Abstract
The objective of this trial was to evaluate a test-and-cull approach to controlling bovine leukemia virus (BLV) in US dairy herds with a low BLV prevalence. Despite worldwide distribution of the virus, 21 nations have eradicated BLV from their dairy cattle and are currently considered 'BLV-free.' In contrast, the US has attempted no industry-wide BLV control programs and has experienced an increase in BLV prevalence among dairy cows to about 40%. This raises concerns about production efficiency, herd health, and sustainability. In a pilot field trial with three Midwestern-US dairy herds, a test-and-cull approach using ELISA screening of milk samples was successful in reducing BLV prevalence in two herds. In the third herd, BLV prevalence increased following the introduction of infected heifers that were raised at an out-of-state calf raising facility. This trial demonstrated that a test-and-cull approach to BLV control can be successful in US dairy herds with low BLV prevalence, but ongoing surveillance is necessary to prevent reintroduction of the virus.
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Affiliation(s)
- Vickie J. Ruggiero
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48823, USA
| | - Paul C. Bartlett
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48823, USA
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10
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Lack of Bovine leukemia virus transmission during natural breeding of cattle. Theriogenology 2019; 126:187-190. [DOI: 10.1016/j.theriogenology.2018.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 11/16/2018] [Accepted: 12/01/2018] [Indexed: 11/20/2022]
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Saushkin NY, Samsonova JV, Osipov AP, Kondakov SE. Strip-dried blood sampling: applicability for bovine leukemia virus detection with ELISA and real-time PCR. J Virol Methods 2018; 263:101-104. [PMID: 30412721 DOI: 10.1016/j.jviromet.2018.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/23/2018] [Accepted: 11/05/2018] [Indexed: 11/18/2022]
Abstract
We recently proposed a new so-called strip-dried format aimed for convenient use of dried biomaterial in diagnostic purposes. In this work, 334 blood samples obtained in strip-dried form were used for bovine leucosis analysis with ELISA and real-time PCR methods. High percentage of seropositive animals (18.3%) let us estimate both indirect (serological) and direct methods applicability for the analysis of strip-dried blood samples and also to compare them (PCR results concurred with ELISA in 93.4% cases). Parallel analysis of native and corresponding strip-dried samples approved the proposed format as a reliable analytical way of sampling being in 100% concordance with conventional serum/whole blood ELISA and PCR analysis. Even distribution of antibodies against bovine leukemia virus along the membrane carrier was demonstrated by square-to-square analyzing of the sample strip (CV not exceeded 7%). Also, strip-dried blood samples showed enhanced stability at elevated temperatures comparing to liquid serum. The proposed strip-blood format is a promising way of sampling, storage and transportation and can find application in veterinary practice for infectious disease monitoring.
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Affiliation(s)
- Nikolay Yu Saushkin
- Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119991, Moscow, Russia.
| | - Jeanne V Samsonova
- Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119991, Moscow, Russia; National University of Science and Technology "MISiS", 119049, Moscow, Russia
| | - Alexander P Osipov
- Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119991, Moscow, Russia; National University of Science and Technology "MISiS", 119049, Moscow, Russia
| | - Sergey E Kondakov
- Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119991, Moscow, Russia; National University of Science and Technology "MISiS", 119049, Moscow, Russia
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12
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Ruiz V, Porta NG, Lomónaco M, Trono K, Alvarez I. Bovine Leukemia Virus Infection in Neonatal Calves. Risk Factors and Control Measures. Front Vet Sci 2018; 5:267. [PMID: 30410920 PMCID: PMC6209627 DOI: 10.3389/fvets.2018.00267] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/05/2018] [Indexed: 11/13/2022] Open
Abstract
Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL). Although efficient eradication programs have been successfully implemented in most European countries and Oceania, BLV infection rates are still high worldwide. BLV naturally infects cattle, inducing a persistent infection with diverse clinical outcomes. The virus infects lymphocytes and integrates a DNA intermediate as a provirus into the genome of the cells. Therefore, exposure to biological fluids contaminated with infected lymphocytes potentially spreads the virus. Vertical transmission may occur in utero or during delivery, and about 10% of calves born to BLV-infected dams are already infected at birth. Most frequently, transmission from dams to their offspring occurs through the ingestion of infected colostrum or milk. Therefore, although EBL is not a disease specific to the neonatal period, during this period the calves are at special risk of becoming infected, especially in dairy farms, where they ingest colostrum and/or raw milk either naturally or artificially. Calves infected during the first week of life could play an active role in early propagation of BLV to susceptible animals. This review discusses the main factors that contribute to neonatal BLV infection in dairy herds, as well as different approaches and management practices that could be implemented to reduce the risk of BLV transmission during this period, aiming to decrease BLV infection in dairy herds.
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Affiliation(s)
- Vanesa Ruiz
- Instituto Nacional de Tecnología Agropecuaria-Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Natalia Gabriela Porta
- Instituto Nacional de Tecnología Agropecuaria-Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Marina Lomónaco
- Instituto Nacional de Tecnología Agropecuaria-Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Buenos Aires, Argentina
| | - Karina Trono
- Instituto Nacional de Tecnología Agropecuaria-Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Irene Alvarez
- Instituto Nacional de Tecnología Agropecuaria-Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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13
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Ruggiero VJ, Benitez OJ, Tsai YL, Lee PYA, Tsai CF, Lin YC, Chang HFG, Wang HTT, Bartlett P. On-site detection of bovine leukemia virus by a field-deployable automatic nucleic extraction plus insulated isothermal polymerase chain reaction system. J Virol Methods 2018; 259:116-121. [DOI: 10.1016/j.jviromet.2018.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 05/08/2018] [Accepted: 06/10/2018] [Indexed: 12/12/2022]
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14
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Kuczewski A, Orsel K, Barkema HW, Kelton DF, Hutchins WA, van der Meer FJUM. Short communication: Evaluation of 5 different ELISA for the detection of bovine leukemia virus antibodies. J Dairy Sci 2017; 101:2433-2437. [PMID: 29274963 DOI: 10.3168/jds.2017-13626] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/01/2017] [Indexed: 11/19/2022]
Abstract
Although Canadian dairy herds have been infected with bovine leukemia virus (BLV) for years, recent research has put new emphasis on the potential negative effects of this infection. Consequently, BLV control is becoming more favorable; however, BLV control cannot be successful without identifying infected animals. Bovicheck BLV (Biovet, Saint-Hyacinthe, QC, Canada) is currently the only assay licensed by the Canadian Centre for Veterinary Biologics. The first goal of this study was, therefore, to determine the reproducibility of the Bovicheck BLV assay for serum samples derived from Canadian cattle. The second goal was to evaluate and compare 5 different ELISA and determine their test characteristics using serum samples from Canadian herds. The considered ELISA were Bovicheck BLV, ID Screen BLV Competition (IDvet, Grabels, France), Idexx Leukosis Serum X2 Ab Test (Idexx Europe B.V., Hoofddorp, the Netherlands), Svanovir BLV gp51-Ab (Svanova, Uppsala, Sweden), and the Serelisa BLV Ab Mono Indirect (Synbiotics, Lyon, France). Eighty serum samples from Canadian cattle provided by Prairie Diagnostic Services (PDS; Saskatoon, SK, Canada) and an additional 80 serum samples from Canadian dairy and beef herds were used for the study. The Bovicheck BLV assay yielded the same results for all PDS-derived samples, implying a high level of reproducibility and robustness of this assay. Additionally, the comparison of the assays' results showed high agreement between assays, with Cohen's kappa values between κ = 0.91 and κ = 1. Furthermore, using original test results of the field samples as true status, relative diagnostic sensitivity and specificity were calculated. Relative diagnostic sensitivity of all tests was 100%. False-positive results were probable; therefore, the following relative diagnostic specificities were determined: 100% for Bovicheck BLV, Idexx Leukosis Serum X2, and Svanovir BLV; 95% for ID Screen BLV; and 97% for Serelisa BLV. When considering other test characteristics, ID Screen BLV is exceptional due to considerable practical advantages.
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Affiliation(s)
- Alessa Kuczewski
- Department of Ecosystem and Public Health, University of Calgary, Calgary, Alberta, Canada T2N 1N4.
| | - Karin Orsel
- Department of Production Animal Health, University of Calgary, Calgary, Alberta, Canada T2N 1N4
| | - Herman W Barkema
- Department of Production Animal Health, University of Calgary, Calgary, Alberta, Canada T2N 1N4
| | - David F Kelton
- Department of Population Medicine, University of Guelph, Guelph ON, Canada N1G 2W1
| | - Wendy A Hutchins
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada T2N 1N4
| | - Frank J U M van der Meer
- Department of Ecosystem and Public Health, University of Calgary, Calgary, Alberta, Canada T2N 1N4
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15
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Choi KY, Monke D, Stott JL. Absence of Bovine Leukosis Virus in Semen of Seropositive Bulls. J Vet Diagn Invest 2016; 14:403-6. [PMID: 12296392 DOI: 10.1177/104063870201400507] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A polymerase chain reaction (PCR)-based detection system was established to identify the presence of bovine leukosis virus (BLV) DNA in bovine semen. Seventy-nine bulls were included in the study. Serum, peripheral blood leukocytes, and semen were collected from each of the 79 bulls. The BLV-specific antibody was detected in serum by agar gel immunodiffusion and viral DNA in blood and semen by PCR. Serologically, 29 of the 79 bulls were BLV positive. Twenty-seven of the 29 seropositive bulls and 1 of the seronegative bulls had BLV DNA in peripheral blood leukocytes. All 79 bulls tested PCR negative for the presence of BLV in semen. This data is strong evidence that properly collected semen from BLV seropositive bulls will not contribute to dissemination of this viral infection.
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16
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Bojarojć-Nosowicz B, Kaczmarczyk E, Stachura A, Kubińska M. Tumor necrosis factor-alpha (TNFα) gene polymorphism and expression of membrane-bound TNFα protein on CD11b+ and IgM+ cells in cows naturally infected with bovine leukemia virus. Pol J Vet Sci 2015; 18:533-9. [PMID: 26618585 DOI: 10.1515/pjvs-2015-0069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to determine whether SNP at position -824 (promoter region) of the TNFα gene significantly differentiates the size of IgM+, CD5+ and CD11b+ cell subpopulations and affects the expression of membrane-bound TNFα protein (mTNFα) on these cells and their susceptibility to BLV infections. In this study, significant differences were determined for the first time between TNFα genotypes and the percentage of cells with the CD11b+TNFα+p24+ immunophenotype. Furthermore, greater expansion of lymphocytes with the IgM+TNFα+p24+ immunophenotype was reported in cows with the G/G genotype than in A/A homozygotes. Cells with the above immunophenotype were more frequently observed in cows with persistent leukocytosis than in aleukemic cattle. Our results suggest that polymorphism of the TNFα-824 A>G gene and mTNFα protein expression play an important role in the pathogenesis of enzootic bovine leukosis.
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18
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Mekata H, Sekiguchi S, Konnai S, Kirino Y, Honkawa K, Nonaka N, Horii Y, Norimine J. Evaluation of the natural perinatal transmission of bovine leukaemia virus. Vet Rec 2014; 176:254. [PMID: 25510867 DOI: 10.1136/vr.102464] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The perinatal transmission of bovine leukaemia virus (BLV) plays a critical role in the spread and persistence of BLV infection in cattle herds. The purpose of this study was to examine the frequency of perinatal infections in an area in Japan and investigate some risk factors associated with infection. Altogether, 129 calves born to BLV-infected cows in a herd in Japan were tested for infection immediately after birth and again at one month of age using nested PCR. Twenty-four calves (18.6 per cent) were infected with BLV, of which 14 (10.8 per cent) and 10 (7.7 per cent) calves were infected via the transplacental and the birth canal routes, respectively. Maternal viral loads, breed, the presence or absence of assistance during parturition and the number of births per dam were evaluated to investigate risk factors associated with infection. Maternal viral load was significantly correlated with the frequency of perinatal infection, and more than 40 per cent of newborn calves born to dams with high viral loads were infected with BLV. The results of this study could contribute towards developing effective eradication programmes by providing necessary data for replacement of breeding cow in the field.
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Affiliation(s)
- Hirohisa Mekata
- Project for Zoonoses Education and Research, Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Satoshi Sekiguchi
- Laboratory of Animal Infectious Disease and Prevention, Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Satoru Konnai
- Laboratory of Infectious Diseases, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18 Nishi 9, Sapporo 060-0818, Japan
| | - Yumi Kirino
- Project for Zoonoses Education and Research, Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan Laboratory of Veterinary Parasitic Diseases, Interdisciplinary Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Kazuyuki Honkawa
- Laboratory of Veterinary Parasitic Diseases, Interdisciplinary Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Nariaki Nonaka
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan Laboratory of Veterinary Parasitic Diseases, Interdisciplinary Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Yoichiro Horii
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan Laboratory of Veterinary Parasitic Diseases, Interdisciplinary Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
| | - Junzo Norimine
- Laboratory of Animal Infectious Disease and Prevention, Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, Miyazaki 889-2192, Japan
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de Castro CC, Nunes CF, Finger PF, Siedler BS, Dummer L, de Lima M, Leite FPL, Fischer G, Vargas GD, Hübner SDO. Peroxidase-linked assay for detection of antibodies against bovine leukosis virus. J Immunoassay Immunochem 2013; 34:376-83. [PMID: 23859788 DOI: 10.1080/15321819.2012.747442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A peroxidase linked assay (PLA) was designed to screen bovine sera for the presence of specific antibodies against bovine leukosis virus (BLV). Out of 201 samples of bovine sera analyzed, 52.2% were considered positive by PLA, 26.4% by AGID, and 38.9% by ELISA. Western blotting analyses excluded 27 samples found to be positive by PLA. PLA showed 100% of sensitivity when compared with AGID and ELISA. Specificity was 64.8% and 78%, respectively (kappa coefficients were 0.70 and 0.83). These findings indicate that PLA can be used as an alternative method for the diagnosis of BLV infection in cattle.
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Affiliation(s)
- Clarissa C de Castro
- Laboratory of Virology and Immunology, Universidade Federal de Pelotas, Pelotas, Brazil
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20
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Rola-Łuszczak M, Finnegan C, Olech M, Choudhury B, Kuźmak J. Development of an improved real time PCR for the detection of bovine leukaemia provirus nucleic acid and its use in the clarification of inconclusive serological test results. J Virol Methods 2013; 189:258-64. [PMID: 23499259 DOI: 10.1016/j.jviromet.2013.02.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 02/21/2013] [Accepted: 02/27/2013] [Indexed: 10/27/2022]
Abstract
With the aim to erradicate Enzootic Bovine Leukosis from Poland, a more sensitive real-time polymerase chain reaction was required and developed to detect proviral Bovine leukaemia virus (BLV) DNA, the causative agent of Enzootic Bovine Leukosis (EBL). This new method proved more sensitive for our needs, than the current protocols available in the public domain. DNA was extracted from peripheral blood leukocytes of 51 cattle, which had given rise to doubtful serological test results by ELISA, and from mesenteric lymph nodes of six cattle that were slaughtered as EBL suspect cases. Additionally, fourteen DNA samples were obtained from animals with a strong BLV antibody response by ELISA. All real-time data were compared to results obtained from three different nested PCR methods. All 14 strongly positive ELISA samples were positive in all PCR tests. The real-time assay in comparison to the conventional PCR methods detected 7.8% (4/51) more specimens positive for BLV nucleic acid and showed a detection limit down to one copy. These observations represent the first report in the value of using a real-time method to help elucidate the disease status of animals when inconclusive ELISA results are obtained in the diagnostic laboratory. Thus, this method should be recommended for use in countries which have implemented an EBL-eradication programme, where a low level of BLV infection is evident.
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Affiliation(s)
- Marzena Rola-Łuszczak
- OIE Reference Laboratory for EBL, Department of Biochemistry, National Veterinary Research Institute, Pulawy, Poland.
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Mohammadabadi M, Soflaei M, Mostafavi H, Honarmand M. Using PCR for early diagnosis of bovine leukemia virus infection in some native cattle. GENETICS AND MOLECULAR RESEARCH 2011; 10:2658-63. [DOI: 10.4238/2011.october.27.2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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23
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Sledge DG, Maes R, Wise A, Kiupel M, Fitzgerald SD. Coinfection of a Cow with Bovine Leukemia Virus and Mycobacterium Bovis. J Vet Diagn Invest 2009; 21:878-82. [PMID: 19901295 DOI: 10.1177/104063870902100621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Bovine leukosis associated with infection with the delta retrovirus Bovine leukemia virus (BLV) is endemic in many cattle herds in the United States. Infection has been associated with immunosuppression and decreased productivity. Cases of tuberculosis in cows due to infection with Mycobacterium bovis reemerged in Michigan in 1998, and despite intensive eradication attempts, new cases of bovine tuberculosis are sporadically identified. The present report details a coinfection with BLV and M. bovis in a Holstein cow from Michigan that presented as part of a bovine tuberculosis screening program. Peripheral and visceral lymph nodes of this animal were markedly enlarged, homogeneously pale white, and bulged on the cut surface. The submandibular, mesenteric, and caudal mediastinal lymph nodes contained multifocal to coalescing caseogranulomas that ranged from 1 to 5 cm in diameter. Histologically, dense sheets of monomorphic populations of neoplastic lymphocytes obliterated the normal architecture of all lymph nodes. Caseogranulomas were characterized by central pools of amorphous degenerate eosinophilic and occasionally mineralized granular debris surrounded by thick rims of epithelioid macrophages, occasional Langhan's type giant cells, and fibrosis. Polymerase chain reaction assay was positive for BLV. Cultures of affected lymph nodes yielded growth of M. bovis.
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Affiliation(s)
- Dodd G. Sledge
- Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI
| | - Roger Maes
- Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI
| | - Annabel Wise
- Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI
| | - Matti Kiupel
- Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI
| | - Scott D. Fitzgerald
- Michigan State University, Diagnostic Center for Population and Animal Health, Lansing, MI
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Acaite J, Tamosiunas V, Lukauskas K, Milius J, Pieskus J. The eradication experience of enzootic bovine leukosis from Lithuania. Prev Vet Med 2007; 82:83-9. [PMID: 17640751 DOI: 10.1016/j.prevetmed.2007.05.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Revised: 05/11/2007] [Accepted: 05/15/2007] [Indexed: 11/26/2022]
Abstract
Before 1985 the situation regarding enzootic bovine leukosis (EBL) in Lithuanian cattle was described only haphazardly. In 1986 serological investigations were initiated together with an eradication programme. The EBL bovine leukosis virus (BLV) situation was monitored by the Institute of Immunology Vilnius University, national and regional veterinary laboratories. Starting in 1986 all EBL-positive cattle were separated from negative cattle into BLV-infected and BLV-free herds. To create the latter, calves were fed pasteurized milk. The seroprevalence in 1990 was 7.29%, but it steadily declined to 0.32% in 2006.
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Affiliation(s)
- J Acaite
- Institute of Immunology Vilnius University, Moletu pl 29, LT-08409 Vilnius-21, Lithuania
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25
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Nagy DW, Tyler JW, Kleiboeker SB. Decreased Periparturient Transmission of Bovine Leukosis Virus in Colostrum-Fed Calves. J Vet Intern Med 2007. [DOI: 10.1111/j.1939-1676.2007.tb03071.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Nagy DW, Tyler JW, Kleiboeker SB. Timing of seroconversion and acquisition of positive polymerase chain reaction assay results in calves experimentally infected with bovine leukemia virus. Am J Vet Res 2007; 68:72-5. [PMID: 17199421 DOI: 10.2460/ajvr.68.1.72] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the interval to provirus and serum antibody detection (via PCR assay and ELISA, respectively) in calves after experimental inoculation with bovine leukemia virus (BLV). ANIMALS 8 colostrum-deprived, BLV-negative Holstein bull calves (> or = 6 weeks old). PROCEDURES Via IM injection, each calf received a fresh whole-blood inoculum (day 0) calculated to contain 2 x 10(6) lymphocytes. Blood samples for the ELISA and PCR assay were collected from calves immediately prior to inoculation and weekly thereafter for 7 weeks. Mean and median number of weeks to PCR-detected conversion of BLV status and seroconversion were calculated. Point sensitivity and cumulative sensitivity of the 2 assays were calculated at each sample collection. At each sampling time, the proportion of calves identified as infected by the cumulative weekly ELISA and PCR assay results was compared by use of a Fisher exact test. RESULTS In 5 calves, conversion of BLV status was detected via PCR assay before seroconversion was identified. However, seroconversion preceded PCR-detected conversion in 2 calves. In 1 calf, both assays yielded positive results at the same test date. These differences were not significant. CONCLUSIONS AND CLINICAL RELEVANCE In experimentally inoculated BLV-negative calves, conversion of BLV status was detected via PCR assay more quickly than via ELISA; this difference was not significant and probably not clinically important. The PCR assay may be useful as a confirmatory test in animals of exceptional value; tests based on viral identification may become critically important if vaccines against BLV infection are developed and marketed.
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Affiliation(s)
- Dusty W Nagy
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
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Monti GE, Frankena K, Engel B, Buist W, Tarabla HD, de Jong MCM. Evaluation of a new antibody-based enzyme-linked immunosorbent assay for the detection of bovine leukemia virus infection in dairy cattle. J Vet Diagn Invest 2006; 17:451-7. [PMID: 16312236 DOI: 10.1177/104063870501700507] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The objective of this study was to validate a new blocking enzyme-linked immunosorbent assay (ELISA) (designated M108 for milk and S108 for serum samples) for detecting bovine leukemia virus (BLV) infection in dairy cattle. Milk, serum, and ethylenediaminetetraacetic acid-blood samples were collected from 524 adult Holstein cows originating from 6 dairy herds in Central Argentina. The M108 and S108 were compared with agar gel immunodiffusion (AGID), polymerase chain reaction and a commercial ELISA. Because there is currently no reference test capable of serving as a gold standard, the test sensitivity (SE) and specificity (SP) were evaluated by the use of a latent class model. Statistical inference was performed by classical maximum likelihood and by Bayesian techniques. The maximum-likelihood analysis was performed assuming conditional independence of tests, whereas the Bayesian approach allowed for conditional dependence. No clear conclusion could be drawn about conditional dependence of tests. Results with maximum likelihood (under conditional independence) and posterior Bayes (under conditional dependence) were practically the same. Conservative estimates of SE and SP (with 95% confidence intervals) for M108 were 98.6 (96.7; 99.6) and 96.7 (92.9; 98.8) and for S108 99.5 (98.2; 99.9) and 95.4 (90.9; 98.1), respectively. The ELISA 108 using either milk or serum to detect BLV-infected animals had comparable SE and SP with the official AGID and a commercial ELISA test, which are currently the most widely accepted tests for the serological diagnosis of BLV infection. Therefore, ELISA 108 can be used as an alternative test in monitoring and control programs.
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Affiliation(s)
- Gustavo E Monti
- Universidad Austral de Chile, Instituto de Medicina Preventiva, Facultad de Ciencias Veterinarias, Valdiva, Chile
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Felmer R, Muñoz G, Zúñiga J, Recabal M. Molecular analysis of a 444 bp fragment of the bovine leukaemia virus gp51 env gene reveals a high frequency of non-silent point mutations and suggests the presence of two subgroups of BLV in Chile. Vet Microbiol 2005; 108:39-47. [PMID: 15885933 DOI: 10.1016/j.vetmic.2005.04.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 04/06/2005] [Accepted: 04/07/2005] [Indexed: 11/17/2022]
Abstract
With the aim of achieve a better understanding of the epidemiology and distribution of bovine leukaemia virus (BLV) infection in Chile, we assessed the suitability of using DNA isolated from the leukocyte fraction of bulk milk samples to carry out PCR-RFLP and DNA sequence analysis. The env fragment of BLV was successfully amplified from 33 serologically positive bulk milk samples collected from different geographical areas in the south of Chile. Restriction analysis allowed to classify 17 isolates within the Australian subgroup and 16 within the Belgium subgroup. DNA sequence and multiple alignment analysis of eight Chilean isolates showed a significantly higher frequency of single and double nucleotide substitutions. Most of these mutations were non-silent, resulting in changes at the protein level in several important epitopes of gp51. The Chilean sequences and 59 BLV env sequences available at GenBank, were subjected to a phylogenetic analysis, resulting in four different clusters. The groups identified were not related to those previously defined by restriction analysis. Chilean isolates were included in two different clusters and were genetically not related to isolates collected from neighbouring countries. Considering our results we can conclude: (i) bulk milk samples are suitable to identify the presence of BLV allowing epidemiological and genetic studies to be conducted on large geographical areas; (ii) at least four different genetic groups of BLV were identified by phylogenetic analysis, with Chilean isolates included in two different sub clusters.
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Affiliation(s)
- R Felmer
- Unidad de Biotecnología, Instituto de Investigaciones Agropecuarias, INIA-Carillanca, Casilla 58-D, Temuco, Chile.
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Monti GE, Frankena K. Survival analysis on aggregate data to assess time to sero-conversion after experimental infection with Bovine Leukemia virus. Prev Vet Med 2005; 68:241-62. [PMID: 15820118 DOI: 10.1016/j.prevetmed.2005.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2004] [Revised: 01/07/2005] [Accepted: 01/07/2005] [Indexed: 11/16/2022]
Abstract
Bovine Leukemia virus (BLV) is a ubiquitous retrovirus that affects mainly cattle. Knowledge of the precise moment of infection is fundamental for identification and evaluation of factors related to BLV transmission. Systematic reviews and meta-analyses provide good evidence on the effects of medical interventions. The objectives were to estimate time to sero-conversion after experimental infection using data from retrieved literature and to detect factors that may influence the length of that interval using survival analysis on pooled data. An analysis using aggregate data from 36 studies totalling 438 observations was performed. From this, four sets were created and analysed by interval-censored accelerated failure time models (AFT) with different distributions (exponential, Weibull, log-logistic, lognormal and generalized gamma), and some variants of the Cox model (Andersen-Gill, smoothing splines) with and without a frailty effect. The AFT gamma model fit best and the estimated median time to sero-conversion in the null model was 57 days (95% confidence interval (CI): 49; 75) using all data and 47 days (95% CI: 39; 55) when only studies using experimental inoculation were considered. Some factors were consistently associated with time to sero-conversion. These included exposure by animal-to-animal contact (resulting in a seven-fold increase in time to sero-conversion compared to direct inoculation), diagnostic method to detect sero-conversion (time to sero-conversion was 1.4 times shorter when AGID was used compared to ELISA), and transmission by insect bites (biological media) delayed sero-conversion 2.3 times compared transmission via needles or other inanimate media. After fitting a frailty Cox model, results showed that sero-conversion in susceptible animals after infection using donors, in which presence of virus before the experiment started was confirmed, increased the hazard of sero-conversion two times in comparison with donors in which virus presence was not confirmed before start of the experiment. Inoculation with blood decreased the hazard 2.5 times in comparison with lymphocyte suspensions. Heterogeneity due to different research groups was also present. Finally, a Cox model with smoothing splines contained three variables: research group, route of inoculation and a non-linear spline for infective dose. In conclusion, it can be stated some factors that influence the time to sero-conversion were identified and quantified and that a moderate influence of research centre existed. These results may contribute to the estimation of the most probable times of infection in field conditions and in a better evaluation of control measures.
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Affiliation(s)
- G E Monti
- Quantitative Veterinary Epidemiology Group, Wageningen Institute of Animal Sciences Wageningen, P.O. Box 338, 6700 AH Wageningen, The Netherlands.
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Lew AE, Bock RE, Molloy JB, Minchin CM, Robinson SJ, Steer P. Sensitive and specific detection of proviral bovine leukemia virus by 5' Taq nuclease PCR using a 3' minor groove binder fluorogenic probe. J Virol Methods 2004; 115:167-75. [PMID: 14667532 DOI: 10.1016/j.jviromet.2003.09.029] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sensitive assays are required to detect proviral bovine leukemia virus (BLV) in donor cattle used for the in vivo preparation of Australian tick fever vaccines. 5' Taq nuclease assays using 3' minor groove binder DNA probes (TaqManMGB) were developed and compared to conventional PCR assays for sensitive detection of Australian BLV. Seven beef and dairy herds were screened using DNA prepared by a variety of protocols to evaluate these tests. Comparative sensitivities of PCR tests were determined by testing log(10) dilutions of plasmids with inserted BLV sequences. Animals were also screened by the BLV standard agar-gel immunodiffusion test (AGID) and commercial enzyme linked immunosorbent assays (ELISA) for antibodies, and an ELISA for detecting viral antigens expressed (VAE) in lymphocyte cultures. The TaqMan MGB assay based on the pol region was the most sensitive and specific for the detection of BLV. This is the first report of a sensitive BLV 5' Taq nuclease assay.
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Affiliation(s)
- Ala E Lew
- Agency for Food and Fibre Sciences, Queensland Department of Primary Industries, c/o Locked Mail Bag No. 4, 4105, QLD, Moorooka, Australia.
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Affiliation(s)
- N. F. Starodub
- Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine
| | - V. M. Starodub
- Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine
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32
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Nagy DW, Tyler JW, Kleiboeker SB, Stoker A. Use of a polymerase chain reaction assay to detect bovine leukosis virus in dairy cattle. J Am Vet Med Assoc 2003; 222:983-5. [PMID: 12685791 DOI: 10.2460/javma.2003.222.983] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the use of a polymerase chain reaction (PCR) assay in detecting bovine leukosis virus (BLV) in adult dairy cows. DESIGN Prospective study. ANIMALS 223 adult dairy cows. PROCEDURE Cows were tested for BLV status by use of an ELISA and a PCR assay. Sensitivity, specificity, predictive values of positive and negative tests, and the percentage of cows correctly classified by PCR assay were calculated. Ninety-five percent confidence intervals were calculated for sensitivity and specificity. RESULTS Sensitivity and specificity were 0.672 and 1.00, respectively. Prevalence of BLV in this herd was 0.807. Predictive value of a positive test was 1.00, and predictive value of a negative test was 0.421. The percentage of cows correctly classified by PCR assay was 73.5%. CONCLUSIONS AND CLINICAL RELEVANCE A positive PCR assay result provided definitive evidence that a cow was infected with BLV. Sensitivity and negative predictive value for PCR assay were low. Consequently, PCR assay alone is unreliable for routine detection of BLV in herds with high prevalence of the disease.
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Affiliation(s)
- Dusty W Nagy
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois, Urbana, IL 61802, USA
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Kuckleburg CJ, Chase CC, Nelson EA, Marras SAE, Dammen MA, Christopher-Hennings J. Detection of bovine leukemia virus in blood and milk by nested and real-time polymerase chain reactions. J Vet Diagn Invest 2003; 15:72-6. [PMID: 12580302 DOI: 10.1177/104063870301500117] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Concerns about retroviruses in livestock and products derived from them have necessitated the development of tests to detect the bovine leukemia virus (BLV) in blood and milk from cattle. Dairy cattle (n = 101) from 5 different geographical areas were used for this study. A nested polymerase chain reaction (PCR) identified 98% of BLV seropositive cattle (n = 80) from blood and 65% from milk, whereas real-time PCR detected 94% of BLV seropositive cattle from blood and 59% from milk. Bovine leukemia virus was also detected by PCR in approximately 10% of seronegative cattle (n = 21), most likely because of early detection before seroconversion.
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Zaghawa A, Beier D, Abd El-Rahim IHA, Karim I, El-ballal S, Conraths FJ, Marquardt O. An outbreak of enzootic bovine leukosis in upper Egypt: clinical, laboratory and molecular-epidemiological studies. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2002; 49:123-9. [PMID: 12019942 DOI: 10.1046/j.1439-0450.2002.00517.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.
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Affiliation(s)
- A Zaghawa
- Department of Animal Medicine and Infections and Fish Disease, Faculty of Veterinary Medicine, Menoufia University, Sadat City, Egypt
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35
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Abstract
A sensitive non-radioactive microplate hybridization assay for the detection of proviral DNA of bovine leukemia virus (BLV)-specific polymerase chain reaction (PCR) product is described. The PCR products are labeled by adding digoxigenin-dUTP to the nested PCR reaction and are captured by a microtitre plate coated with oligonucleotide probe, which is complementary to the inner region of the amplification product. Captured products are reacted with an anti-DIG Fab fragment conjugated to peroxidase, and detected using a colorimetric reaction. The PCR-enzyme linked immunosorbent assay (ELISA), detecting as low as 10(-4) ng of proviral DNA in a background of 1 microg of BLV-negative DNA, was up to 100-fold more sensitive than ethidium bromide staining, and showed equal sensitivity to Southern blot hybridization. Using this method it was possible to monitor the presence of proviral DNA in four sheep infected experimentally with BLV, over a 10 months postinfection period, as well as in 29 cattle infected naturally. The test is rapid and highly sensitive and is a useful additional tool for the detection of BLV-infected animals.
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Affiliation(s)
- M Rola
- National Veterinary Research Institute, Al.Partyzantow 57, 24-100, Pulawy, Poland
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36
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Trono KG, Pérez-Filgueira DM, Duffy S, Borca MV, Carrillo C. Seroprevalence of bovine leukemia virus in dairy cattle in Argentina: comparison of sensitivity and specificity of different detection methods. Vet Microbiol 2001; 83:235-48. [PMID: 11574172 DOI: 10.1016/s0378-1135(01)00420-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Bovine leukemia virus (BLV) is a retrovirus that induces a chronic infection in cattle, which develop in three possible pathological forms: asymptomatic course, persistent lymphocytosis (PL) and lymphosarcoma. Once infected, cattle remain virus carriers for life and start to show a serological reaction within a few weeks after infection. Eradication and control of the disease is based on early diagnostic and segregation of the carriers. The agar gel immunodiffusion (AGID) test has been the serological test of choice for routine diagnosis of serum samples. Nevertheless, in more recent years, the enzyme-linked immunosorbent assay (ELISA) has replaced the AGID for large scale testing. Although Argentina has over 60 million cattle population, no nationwide studies have been conducted yet to determine the prevalence of the infection. To estimate the rate of BLV infection in dairy cattle in Argentina, a survey for specific antibodies in >10,000 serum samples from animals over 18 months old, belonging to 363 different herds from the largest dairy production areas of the country, was carried out in our laboratory, along 1999. For this purpose, we developed an ELISA to detect serum antibodies against the BLV virus. The cut-off of the ELISA was established over 339 serum samples, using polymerase chain reaction and southern blot (PCR-SB) as confirmatory test. The sensitivity and specificity of the ELISA was of 97.2 and 97.5%, respectively, while the local official AGID test showed a sensitivity of 79.7% and specificity of 99.0%. To know the seroprevalence of BLV on dairy herds, and also the incidence of the infection within the herd, the serological survey was based on individual serum samples. The results show that the prevalence of infected individuals is of 32.85%, while the percentage of infected herds, harboring one or more infected animals, is of 84%. These results indicate a medium level of seropositive animals when taken individually, but a high prevalence of infected farms, which has been notoriously increased in the last 15 years as shown when compared with previous data from particular geographic areas, indicating that BLV constitutes a serious sanitary problem for dairy producers in Argentina. They also indicate the poor sensitivity of the official AGID test used in the country.
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Affiliation(s)
- K G Trono
- Instituto de Virología, C.I.C.V.yA. INTA Castelar, Morón 1708, Pvcia., Buenos Aires, Argentina
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Gutiérrez SE, Dolcini GL, Arroyo GH, Rodriguez Dubra C, Ferrer JF, Esteban EN. Development and evaluation of a highly sensitive and specific blocking enzyme-linked immunosorbent assay and polymerase chain reaction assay for diagnosis of bovine leukemia virus infection in cattle. Am J Vet Res 2001; 62:1571-7. [PMID: 11592321 DOI: 10.2460/ajvr.2001.62.1571] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To develop a blocking ELISA for detection of bovine leukemia virus (BLV) antibodies that is comparable to a radioimmunoprecipitation (RIP) assay, to evaluate use of this ELISA for identification of BLV-infected herds, and to develop a polymerase chain reaction (PCR) assay for direct diagnosis of infection with BLV. SAMPLE POPULATION Serum samples and pooled bulk-tank milk samples from cattle. PROCEDURE The blocking ELISA was developed, using BLV gp51 as antigen, captured by a selected bovine polyclonal serum. A nested PCR was conducted with primers specific for a segment of the pol region of the BLV genome. RESULTS Sensitivity and specificity of the ELISA were comparable to those of the RIP assay. Use of the ELISA on pooled milk samples allowed identification of herds in which prevalence of BLV infection among lactating cows was as low as 2.5%. Pooled milk samples from BLV-free herds did not react in the ELISA. All cattle that had positive results for the nested PCR had BLV antibodies, but cattle with consistantly low antibody titers required examination of sequential DNA samples to detect viral sequences. None of the 63 antibody-negative cattle had positive results for the PCR. CONCLUSIONS AND CLINICAL RELEVANCE This ELISA is a highly specific and sensitive assay for the detection of BLV antibodies in serum and milk samples of cattle. Examination of pooled milk samples with the ELISA provides a reliable, practical, and economic procedure for identification of BLV-infected herds. The nested PCR also constitutes a specific procedure for direct diagnosis of infection with BLV.
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Affiliation(s)
- S E Gutiérrez
- Departamento de Sanidad Animal y Medicina Preventiva, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Argentina
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38
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Martin D, Arjona A, Soto I, Barquero N, Viana M, Gómez-Lucía E. Comparative study of PCR as a direct assay and ELISA and AGID as indirect assays for the detection of bovine leukaemia virus. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2001; 48:97-106. [PMID: 11315529 DOI: 10.1046/j.1439-0450.2001.00424.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The choice of a diagnostic method depends on the characteristics of the herd to be analysed. Two herds with different prevalences of enzootic bovine leukaemia were chosen to study the concordance between agar gel immunodiffusion (AGID), enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods. PCR, an increasingly used virological method, was performed with four sets of primers, amplifying different genomic regions (env, pol and tax), from DNA extracted either from peripheral blood monocytes (PBMCs) or milk leucocytes. The highest percentage of positive animals was obtained using PCR performed with DNA extracted from PBMCs using primers which amplified either env or pol, followed by PCR using PBMCs and primers which hybridized with tax, then ELISA using serum and finally AGID. The results of PCR were more consistent with PBMCs than when milk leucocytes were used.
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Affiliation(s)
- D Martin
- Departamento Patología Animal I, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
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39
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Gonzalez E, Oliva G, Norimine J, Cid de la Paz V, Echeverría M. Evaluation of western blotting for the diagnosis of enzootic bovine leukemia. ARQ BRAS MED VET ZOO 1999. [DOI: 10.1590/s0102-09351999000400002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A western blotting (WB) procedure has been developed for detecting antibodies to bovine leukosis virus (BLV) in cattle sera. Two hundred and thirty three serum samples from naturally infected cattle with BLV virus and serial bleedings from experimentally BLV infected cows were used. An agar gel immunodiffusion test (AGID) was used for comparing with the results obtained by WB. The AGID positive sera showed a different degree of reactivity by WB test against the two most important viral antigens (gp51 and p24), or against one of them. Other proteins (gp30, p15, p12 and p10) were not detected with any AGID positive sera, being observed occasionally three bands corresponding to the p24 protein. Using sera obtained by BLV experimental inoculation, the antibodies directed to p24 appeared early (between the 2nd and 4th week post inoculation) and thereafter antibodies to gp51were detected in some animals. The analysis of field serum samples by AGID as compared to WB showed an agreement of 90.9%. Only 1.7% of sera were negative by AGID and positive by WB and 7.2% that were not conclusive by AGID and were defined by WB (4.2% as positive and 3.0% as negative).
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Affiliation(s)
| | - G.A. Oliva
- Universidad Nacional de La Plata, Argentina
| | - J. Norimine
- Plant and Animal Biotechnology Laboratory, USA
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40
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González ET, Norimine J, Valera AR, Travería G, Oliva GA, Etcheverrigaray ME. A rapid and sensitive diagnosis of bovine leukaemia virus infection using the nested shuttle polymerase chain reaction. PESQUISA VETERINARIA BRASILEIRA 1999. [DOI: 10.1590/s0100-736x1999000200002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Bovine leukaemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL). In Argentina, where a program to eradicate EBL has been introduced, sensitive and reliable diagnosis has attained high priority. Although the importance of the agar gel immunodiffusion test remains unchanged for routine work, an additional diagnostic technique is necessary to confirm cases of sera with equivocal results or of calves carrying maternal antibodies.Utilizing a nested shuttle polymerase chain reaction, the proviral DNA was detected from cows experimentally infected with as little as 5 ml of whole blood from BLV seropositive cows that were nonetheless normal in haematological terms. It proved to be a very sensitive technique, since it rapidly revealed the presence of the provirus, frequently at 2 weeks postinoculation and using a two-round procedure of nested PCR taking only 3 hours. Additionally, the primers used flanked a portion of the viral genome often employed to differentiate BLV type applying BamHI digestion. It is concluded that this method might offer a highly promising diagnostic tool for BLV infection.
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41
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Russo S, Montermini L, Berkovitz-Siman-Tov R, Ponti W, Poli G. Expression of bovine leukemia virus ENV glycoprotein in insect cells by recombinant baculovirus. FEBS Lett 1998; 436:11-6. [PMID: 9771885 DOI: 10.1016/s0014-5793(98)00951-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The gp51-p30 glycoprotein constituting BLV envelope was expressed in Sf-21 insect cells by means of recombinant baculoviruses. Post-infection cell lysates were analyzed, in order to define the immunologic reactivity of recombinant products. Oligosaccharide chains, containing N-acetylglucosamine, mannose, galactose and sialic acid were found on recombinant gp51-p30. In order to investigate the timing of transcription and translation of the glycoprotein, kinetic assays were carried out on cell lysates and directly in situ on Sf-21 cells during the course of baculovirus infection. The use of different solubilizing reagents was also evaluated in order to rescue recombinant glycoprotein from its subcellular location.
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Affiliation(s)
- S Russo
- Institute of Microbiology and Immunology, Faculty of Veterinary Medicine, Milan, Italy
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42
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Reichel MP, Tham KM, Barnes S, Kittelberger R. Evaluation of alternative methods for the detection of bovine leukaemia virus in cattle. N Z Vet J 1998; 46:140-6. [PMID: 16032038 DOI: 10.1080/00480169.1998.36078] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AIM To evaluate commercially available enzyme-linked immunosorbent assays (ELISAs) and the polymerase chain reaction (PCR) for their ability to detect antibodies against or nucleic acid of the bovine leukaemia virus (BLV), the causal agent of enzootic bovine leukosis (EBL), and to assess their usefulness in a national eradication programme. METHODS Eighty-two well-defined sera (including 18 from an OIE reference laboratory) and 399 field sera from New Zealand cattle were tested in five ELISAs and the results compared with the agar gel immunodiffusion (AGID) test and electrophoretic immunoblotting (EIB) results. A polymerase chain reaction-based technique, which could detect BLV-RNA and proviral-DNA, was also evaluated on a subsample of the field cases. RESULTS Two commercial ELISAs classified 99% of the defined sera correctly, with the other three ranging in their correct classification between 88% and 95%. The ELISAs agreed in their general classification on the majority of the 399 blood samples (91.7%), and with the AGID for more than 95 % of the sera. In a dilution series of the international reference serum E4, the highest dilution with a positive (or suspicious) result ranged from 1:80 to 1:5120. A dilution series of 202 field positive samples tested in the preferred ELISA detected 98% of positive sera at a 15 and 1: 10 dilution, reducing to 78% at a 1:80 dilution of the sera. Agreement between serological tests and PCR was poor, mainly due to failure of the PCR to detect a number of serologically positive animals. CONCLUSION ELISA tests detected about 10% more reactors than the AGID and the EIB combined. Some ELISA-positive animals were not detected by PCR, raising doubts about the usefulness of PCR-based technology in EBL eradication programmes.
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Affiliation(s)
- M P Reichel
- Central Animal Health Laboratory, MAF Quality Management, Wallaceville, P.O. Box 40063, Upper Hutt, New Zealand.
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43
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Evermann JF, Jackson MK. Laboratory diagnostic tests for retroviral infections in dairy and beef cattle. Vet Clin North Am Food Anim Pract 1997; 13:87-106. [PMID: 9071748 DOI: 10.1016/s0749-0720(15)30366-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Detection of bovine retroviruses stretches our diagnostic creativity to its limits. The nucleic acid-based, PCR-amplified assays are finding increased clinical use as the veterinary and livestock industry seek earlier detection of infection for eventual corrective management decisions. We are evolving from a point of disease diagnosis by tumor identification through conventional histopathology, to molecular diagnostics for early identification of retroviral nucleic acid (provirus). The clinical use of antibody-based assays lies in the simplicity of testing large numbers of animals, the relative sensitivity of the assays, and the low cost of testing. Although the pathogenicity of bovine leukemia virus (BLV) for cattle has been well documented, the disease potential for bovine immunodeficiency-like virus (BIV) for cattle is still being determined. Nevertheless, pressure to test for retroviral infections of livestock and, when feasible, removal of these infected animals from the herd will be increased.
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Affiliation(s)
- J F Evermann
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, USA
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44
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Klintevall K, Fuxler L, Fossum C. Bovine leukemia virus: early reflections in blood after an experimental infection of calves. Comp Immunol Microbiol Infect Dis 1997; 20:119-30. [PMID: 9208197 DOI: 10.1016/s0147-9571(96)00043-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In order to study early alterations in the blood following infection with bovine leukemia virus (BLV) in the natural host, 15 calves were inoculated with blood from a BLV-positive donor cow. The humoral immunological response was followed by ELISA for 2 months. Seroconversion to BLV was demonstrated at 4-5 weeks post-infection. Total and differential leukocyte counts were performed. Acute lymphocytosis was observed at the time of seroconversion in the majority of the experimental calves. By the aid of monoclonal antibodies (mAbs), the proportion as well as the total number of lymphoid cells were studied in four of the calves, applying analytical flow cytometry. At the time of seroconversion the percentage of B-cells increased from 19.1 +/- 7.5% to 37.9 +/- 15.8%, and the T-cells (CD2+) decreased from 36.7 +/- 7.3% to 22.7 +/- 6.0%, the latter being attributable to decreases in the percentage of CD4+ as well as CD8+ T-cells for the infected calves together. Subsequently, altered B/T ratios were observed. In one of the calves an increase in the absolute number of CD5+ cells coincided with an increase in total B-cells. The early phenotypic alterations in lymphocyte subsets, before and after seroconversion to BLV, were comparable to those of non-lymphocytotic and persistent lymphocytotic cattle, respectively. Sera from 15 calves were tested for the presence of interferon (IFN), as measured by antiviral activity. BLV does not appear to induce the production of IFN.
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Affiliation(s)
- K Klintevall
- National Veterinary Institute, Department of Virology, Uppsala, Sweden
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45
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Fechner H, Kurg A, Geue L, Blankenstein P, Mewes G, Ebner D, Beier D. Evaluation of polymerase chain reaction (PCR) application in diagnosis of bovine leukaemia virus (BLV) infection in naturally infected cattle. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1996; 43:621-30. [PMID: 9011158 DOI: 10.1111/j.1439-0450.1996.tb00361.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The practical application of polymerase chain reaction (PCR) for the diagnosis of bovine leukaemia virus (BLV) infections in naturally infected cattle was evaluated. Compared to serological tests the PCR was definitely found to be a more sensitive method, yielding the highest number of positive results (10% more compared to enzyme-linked immunosorbent assay, (ELISA), and 17.7% more compared to agar-gel immunodiffusion, (AGID)). In testing cattle from herds with BLV incidence under 5%, out of 52 provirus positive cattle only 43 were correctly identified by ELISA. When compared to AGID only 37 of the 52 PCR positive animals were correctly identified. Of 18 cattle imported from the Slovak Republic and kept in a quarantine stable, four were found to be BLV provirus positive by PCR, while serological tests indicated one animal positive and three negative. Therefore, it is impossible to prevent the spread of the infection from one country to another by serological testing only. Moreover, it is feasible to identify animals with changing antibody titres correctly by PCR. Using PCR we were also able to distinguish BLV infected from uninfected calves that were serologically positive due to colostral antibodies. Higher sensitivity of BLV provirus detection by PCR was achieved using env gene rather than tax gene specific primers. Negative results by PCR in cases of positive serological reactions are still possible, as shown in case of one adult animal. These findings indicate that PCR is a highly sensitive method and might be successfully used and economically advantageous for different practical applications in detection of BLV infection in naturally infected cattle.
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Affiliation(s)
- H Fechner
- Institute of Virology, Faculty of Veterinary Medicine, Free University Berlin, Germany
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Pfeffer M, Wiedmann M, Batt CA. Applications of DNA amplification techniques in veterinary diagnostics. Vet Res Commun 1995; 19:375-407. [PMID: 8560754 PMCID: PMC7089009 DOI: 10.1007/bf01839319] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/1995] [Indexed: 01/31/2023]
Abstract
An overview of the principles of the polymerase chain reaction, ligase chain reaction, self-sustained sequence replication and Q beta replicase is given. The application of these methods for the diagnosis of veterinary infectious and hereditary diseases as well as for other diagnostic purposes is discussed and comprehensive tables of reported assays are provided. Specific areas where these DNA-based amplification methods provide substantial advantages over traditional approaches are also highlighted. With regard to PCR-based assays for the detection of viral pathogens, this article is an update of a previous review by Belák and Ballagi-Pordány (1993).
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Affiliation(s)
- M Pfeffer
- Institute for Medical Microbiology, Infectious and Epidemic Diseases, Ludwig-Maximilians University, Munich, Germany
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