Metalloproteomic approach of macro and microminerals in Nelore cattle finished in feedlot with different levels of corn gluten feed

Author(s)

Wellington Luiz de Paula Araújo

• Document type: Doctoral Thesis
• Press: Botucatu. 2022-03-04.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Medicina Veterinária e Zootecnia. Botucatu
• Defense date: 2022-02-12
• Advisor: Pedro de Magalhães Padilha; Mário De Beni Arrigoni; José Cavalcante Souza Vieira

Abstract

Although the proteomic profile of the longissimus thoracis muscle has been reported in studies in Brazil and in other countries, the data available in the literature on alterations in the bovine proteome are still few, mainly on alterations in the protein profile and in the interaction with minerals in beef cattle. In the Nelore breed these difficulties become even greater. Manuscript 1 (Chapter II): the goal of the present study was to evaluate the effects of different levels of Corn Gluten Flour (DCGF – “Dry Corn Gluten Feed”) in the finishing diet of uncastrated male Nellore cattle on beef quality and the metalloproteome of muscle tissue and meat. Manuscript 2 (Chapter III): aimed to evaluate the inclusion of different levels of DCGF in the mineral and protein (metalloproteomic) profile of the liver tissue of Nellore cattle in feedlot finishing and in the expression of important proteins in animal metabolism. For this, 120 bovines, not castrated males, of the Nelore breed, with an average initial weight of 361 kg, coming from pasture, from the same herd, were used. The experimental diets were composed of different levels of inclusion of DCGF (0%, 18%, 36% and 54%) in replacement of corn grain. After the collection of biological samples, the proteome was obtained by 2D PAGE, and using ImageMaster 2D Platinum 7.0, analyzes of expression of protein spots. Protein identification was performed by liquid chromatography-mass spectrometry (LC-MS/MS). Then, the minerals were determined by flame atomic absorption spectrometry (FAAS) and graphite furnace (GFAAS). Finally, bioinformatics studies were identified using specific software, functional levels, metabolic pathways and metal-protein interactions. The results showed differences in the expression of muscle tissue and meat proteins. However, corn gluten meal (DCGF) was not shown to be harmful to liver health, with iron and zinc being the main minerals in the study, appearing more frequently in protein spots. The inclusion of DCGF in finishing diets increased dry matter intake, daily weight gain and final body weight of Nellore cattle. Therefore, the use of dry corn gluten meal is indicated as a viable alternative for inclusion in the diet when it comes to these parameters, since it did not negatively affect the final product, nor did it harm animal health. (AU)

• FAPESP's process: 18/25969-8 - Characterization of macro and micro minerals biomarkers in muscle and liver tissues of Nelore beef cattle finished in the feedlot using metalloproteomic strategies
• Grantee: Wellington Luiz de Paula Araújo
• Support Opportunities: Scholarships in Brazil - Doctorate