Study of digestive system tight junctions and inflammatory markers of feedlot nellore cattle fed diets for high performance

• Grant number: 20/11555-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2021
• End date: February 28, 2022
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Danilo Domingues Millen
• Grantee: Breno Leite Demartini
• Host Institution: Faculdade de Ciências Agrárias e Tecnológicas. Universidade Estadual Paulista (UNESP). Campus de Dracena. Dracena , SP, Brazil

Abstract

Diets formulated to promote high performance in feedlot beef cattle often promote lesions in the digestive epithelium, which result in increased inflammation, without nutritionists or feeders being able to identify or measure this impact. However, the adjustments we believe can be made in these diets in order to maintain the high performance of feedlot cattle without promoting inflammation. Therefore, the hypothesis of this study is that nutritional protocols properly formulated to promote high performance in feedlot cattle can mitigate the impact of injuries on the digestive tract as a whole and reduce inflammatory markers in the blood. This project aims to evaluate the effect of different ways of processing the corn grain in diets with or without inclusion of rumen-protected fat, as well as zinc and organic chromium, on the morphometry and integrity of the epithelium of the gastrointestinal tract, which includes rumen, jejunum and cecum, blood inflammation markers, and fecal starch content in feedlot Nellore cattle. 150 Nellore bulls, with an initial body weight of 380 kg, blocks by weight. On day 0 of the experimental period, one animal per pen (n = 30) will be slaughtered as a reference; and in this way the study will continue with 120 animals, randomly divided into 30 pens (n = 4 per pen). The experimental period will be 112 days, which will include 14 days of adaptation and 98 days of finishing with different high-performance diets according to the treatments: 1) Finely-ground corn; 2) High-moisture corn; 3) Finely-ground corn + rumen-protected fat; 4) High-moisture corn + rumen-protected fat; 5) High-moisture corn + rumen-protected fat + Zn and Cr. Sodium monensin will be added at 25 ppm in all treatments. Blood and feces samples will be collected during the study for analysis of inflammatory markers in the blood and fecal starch content, respectively, at the beginning and at the end of the study. After slaughter, fragments of the rumen, jejunum and cecum will be collected for future analysis of morphometry and immunohistochemistry of the tight junctions. This master's scholarship proposal is part of the Regular Research Grant 2019 / 24747-4 granted by FAPESP. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

DEMARTINI, Breno Leite. Nutritional protocols to preserve cell tight junctions of the gastrointestinal tract and to decrease blood inflammatory markers of feedlot cattle. 2022. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Medicina Veterinária e Zootecnia. Botucatu Botucatu.