Identification of Bovine Leukemia Virus (BLV) in Milk: Scoping review

Abstract

Introduction: Since 2019, there has been a growing interest in assessing the potential risks of animal viral infections mutating into a form dangerous for humans. Research in the field of livestock product safety is being conducted in several directions, including the analysis and assessment of the impact of the most common cattle diseases on the quality and safety of the raw materials obtained. Of particular interest is the identification of Bovine Leukemia Virus (BLV) in milk. Monitoring this virus will not only allow for the timely tracking of its presence in farmsteads, but also to evaluate the quality and safety of raw milk used for further dairy product production.Purpose: To analyze the main research directions in the field of molecular-genetic approach to the detection of bovine leukemia virus in cow's milk.Materials and Methods: This scoping review was carried out according to the  protocol PRISMA-ScR. The articles were selected from the SCOPUS and ScienceDirect databases. The main criterion for including a publication in the review was the presence of information about the detection of BLV in milk by PCR method. Acceptance criteria also included document language (English), its type and status (published, peer-reviewed, review, and empirical articles) with no limitations on years.Results: In total, 3688 documents were extracted, among which a screening for duplicates was carried out, resulting in the extraction of 2905 search results for further analysis. At the stage of selecting publications by title and abstract, 2601 articles that did not match the context of the subject field review and the type of publication were excluded. Upon studying the full text of 38 articles, 23 were excluded. As a result of the analysis of the selected sources, 15 publications were included in the review. The studies analyzed were based both on simple and multi-stage methods of BLV identification. The source of biomaterial were blood, colostrum, raw milk, and meat from different animal samples.Conclusion: This scoping review is the first to summarize molecular-genetic approaches to the detection of BLV in milk. The presented results indicate the presence of a scientific base of methods for identifying BLV for further development of methods for controlling the presence of the virus and its proviral load in products, tightening control over the spread of economically harmful infectious diseases, potentially directly or indirectly dangerous for any consumer of dairy products.