Assessment of gene expression of inflammatory cytokines by qPCR in post-drying dairy cows.

• Grant number: 24/07129-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2024
• End date: June 30, 2025
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Wanderson Adriano Biscola Pereira
• Grantee: Mariana Arnaldi Petrosino
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

During drying, the mammary gland undergoes active involution to return to a non-lactating state. Abrupt drying leads to engorgement of the mammary ducts and changes in the composition of breast secretion, triggering an involution process that involves programmed cell death and inflammation. Thus, the objective of this study is to evaluate gene expression of TNF-±, IL-1² and IL-6 in cows after drying, using the qPCR technique. Clinically healthy cows with milk production greater than 15 kg/day will be used. Samples of 20 mg of liver tissue will be collected through percutaneous biopsies with "Tru-Cut" needles guided by ultrasound. The samples will be immediately placed in cryotubes, placed in liquid nitrogen and transported to the laboratory where they will be stored at -80°C. Total RNA extraction will be carried out from the hepatic fragments, using centrifugation columns and cDNA synthesis for the reactions will then be carried out. To quantify the mRNA expression of acute phase proteins, a TaqMan real-time PCR method with relative quantification will be used. A reference gene (GAPDH) will be processed simultaneously in qPCR for each sample as an endogenous control. One-Way ANOVA analysis of variance (p<0.05) will be performed to determine differences in gene expression between the evaluated moments.