Ruminal bacterial communities and characterization of intramuscular fat regulating genes of Nellore cattle submitted to different nutritional strategies to improve marbling

• Grant number: 19/23979-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2022
• End date: December 31, 2025
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Danilo Domingues Millen
• Grantee: Johnny Maciel de Souza
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated scholarship(s): 22/15250-1 - Microbial metaproteome and metagenome from rumen and cecum of Nellore cattle supplemented with narasin, BE.EP.PD

Abstract

The objective of the present study is to evaluate the proteome of the Longissimus dorsi muscle (LD) in Nellore cattle, associated with marbling characteristics, in order to find differentially expressed proteins, co-expression networks and metabolic pathways that regulate these characteristics, and correlate with the expression of genes in the gastrointestinal tract and rumen and cecum microbiome. 64 non-castrated Nellore cattle will be used. The finishing diets will contain 87% concentrate and the treatments will be: 0 and 20 ppm of narasin. The experimental design will be in completely randomized blocks. Fat thickness, rib eye area and LD marbling will be measured. The animals will be slaughtered in a commercial slaughterhouse after 112 days of confinement. LD samples (between the 12th and 13th ribs), as well as fragments of the ruminal and cecal epithelia will be collected immediately after slaughter for further analysis of proteome. Samples of ruminal and cecal epithelia will also be analyzed for morphometry and histology. Samples of rumen and cecal content will be collected and destined for sequencing of microbial community, metaproteome and metabolome. (AU)