Doppler ultrasonography and the expression of interferon-tau stimulated genes for early diagnosis of gestation in heifers and dairy cows

• Grant number: 19/16040-8
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2019
• End date: March 31, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Pietro Sampaio Baruselli
• Grantee: Priscila Assis Ferraz
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 15/10606-9 - Innovations in the early pregnancy diagnosis in cattle, AP.JP

Abstract

Early diagnosis of gestation is an important tool to increase the reproductive efficiency and profitability of dairy herds. Interferon-tau is a glycoprotein secreted by the embryo and essential for the maternal recognition of the embryo. Secretion of IFN-tau during embryo implantation stimulates the expression of genes (ISGs) in peripheral blood immune cells in blood females and can be used as a method for the early diagnosis of gestation. A better accuracy in the identification of the expression of interferon-tau stimulated genes in mononuclear cells (PBMCs) and polymorphonuclear cells (PMNs) in peripheral blood, whole blood and milk of dairy cows, and the definition of the best methods for early detection of gestation in dairy females should be explored. Thus, the objectives of this study are to evaluate the accuracy of the use of ISGs expression in blood /milk samples compared to the use of Doppler ultrasonography to diagnose gestational status early in dairy females. Therefore, will be realized in Study 1, characterization and comparison of ISGs expression in PMNs and PBMCs, evaluation of the use of immune cells isolated from milk and the use of mRNA extracted from whole blood will be performed to determine the expression of ISGs in dairy cows and heifers. In Study 2, the best method to determine the expression of ISGs compared to US Doppler for the early diagnosis in dairy cows and heifers will be made. Thus, it is expected that this project will develop new methods for the early diagnosis of gestation in dairy females that will contribute to the increase of reproductive efficiency and improvement in the productivity of dairy herds.