Meat quality and differential gene expression of pigs from different genetic lines

• Grant number: 23/02067-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: June 01, 2023
• End date: February 28, 2025
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Principal Investigator: Aline Silva Mello Cesar
• Grantee: Julia Dezen Gomes
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Crossbreeding between breeds or lines of pigs can be used as an important tool for the efficiency of animal production and improvement in meat quality characteristics in order to meet the demands of the production chain and pork consumers. The main factors that influence the quality of the meat are: age, sex, nutrition, management, welfare and genetics of the animals. The quality attributes of pork, such as juiciness, tenderness, flavor, pH and color can influence the consumer positively or negatively at the time of purchase, and genetics is a very relevant factor for these attributes. However, the knowledge of the biological mechanisms associated with these genetic differences, lines selected for different production attributes and meat quality, still have many gaps and little is known about the expression level of the main genes associated with the quality attributes of pork meat in different commercial crossbreeds. Thus, this study aims to evaluate performance and consumption characteristics, as well as carcass and meat quality attributes and the gene expression level of genes related to biological mechanisms associated with these attributes among different genetic lines of pigs. A total of 528 crossbred pigs of different genetic lines will be used: (1) F1 x pure Duroc crossbreed (n=176); (2) F1 x hybrid male (50% Duroc x 50% Pietrain) crossbreed (n=176); and (3) F1 x commercial line male crossbreed (n=176), which will receive commercial basal diets formulated to meet the minimum nutritional requirements for growing and finishing pigs. Throughout the experiment, the animals will be submitted to weekly individual weighings to obtain growth curves, in addition to evaluations of lard thickness, loin depth and loin eye area by ultrasonography. Performance and consumption measurements will be obtained weekly per stall. At the end of the experimental period, blood samples will be collected. At the moment of the slaughter, Longissimus lumborum muscle samples will be collected for gene expression studies and 24 hours after the slaughter, carcass and meat quality analyses will be performed, such as loin eye area, hot and cold carcass weight, fat thickness, pH, color, cooking loss, dripping loss, tenderness and intramuscular fat percentage. Through the results obtained in this study it is expected to identify differences in performance attributes, consumption, carcass and meat quality and the level of expression of genes related to important biological mechanisms that will contribute to a better biological understanding of these traits of economic interest and the better direction of pork production worldwide.