Metagenomics of rDNA 16S V2-v3 region for identification of bovine mastitis pathogenic microorganisms

• Grant number: 20/15154-7
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2021
• Effective date (End): December 31, 2021
• Field of knowledge: Agronomical Sciences - Animal Husbandry
• Principal researcher: Luiz Lehmann Coutinho
• Grantee: Giovanna Silva Sartori
• Home Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Milk productivity is influenced by several factors, including animal health, where in this case mastitis stands out as the main source of loss in production. Mastitis is an inflammation of the bovine mammary gland and is considered one of the main problems related to financial losses and milk production losses, making the raw material of low quality, directly affecting the food industry and the final consumer. The standard form for identifying pathogenic microorganisms causing mastitis is by culture; however, molecular technologies that can provide faster and more accurate results have been used. Molecular biology and in particular genomics contributes by identifying many microorganisms at once and independently of culture. Studies use the 16S gene to determine which microorganisms are present in certain samples, combining the variants of the 16S sequence by referencing databases as SILVA. But using this gene, there's a limitation to some genera of microorganisms, where you can't get to the species level by sequencing a single region like V4, making it impossible to identify at species level, all important bovine mastitis pathogens. Therefore, the objective of this study is to test whether a region (V2-V3) of the 16S gene classifies mastitis-causing pathogens better in dairy cattle, than the most well-known and currently employed regions V3-V4 and V4. For this purpose, PCR reactions will be used to amplify the V2-V3 region of the 16S rDNA gene from milk samples and bioinformatics sequencing analysis will be performed. The results will be compared with the sequencing already performed for the same samples, but using the V4 region. (AU)