Adaptation to high-energy diets in non-conventional production systems for beef cattle.

• Grant number: 24/07544-0
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2025
• End date: April 30, 2028
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Danilo Domingues Millen
• Grantee: Danilo Domingues Millen
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated researchers: Camila Cesario Fernandes ; Garret Suen
• Associated scholarship(s): 25/09684-7 - Adaptation to non-forage feedlot diets for Nellore cattle., BP.MS

Abstract

This project aims to evaluate different nutritional protocols to adapt beef cattle to high-energy diets in non-conventional production systems: no-forage diets and diets for intensive finishing on pasture (TIP). Three experiments will be conducted, with the following treatments in studies 1 and 2: 1) Control: 14-day adaptation on step-up to the conventional finishing diet containing forage sources; 2) 14-day restriction: adaptation by quantitative restriction to a finishing diet with no forage; and 3) 21-day restriction: adaptation by quantitative restriction to a finishing diet with no forage. In study 3, about TIP, the treatments will be: 1) 21-day adaptation, with an initial concentrate offer at 0.5% of body weight (BW); 2) 14-day adaptation, with an initial concentrate offer at 0.5% of BW; 3) 14-day adaptation, with an initial concentrate offer at 1.0% of BW. The objective is to reach 2,0% of BW, in terms of concentrate intake, at the of the adaptation period. In studies 1 (n=144) and 3 (n=28) variables related to performance, carcass characteristics, feeding behavior, rumen and cecum morphometry, as well as ruminal bacteria and protozoa will be evaluated in Nellore bulls. In study 2, six cannulated Nellore cattle will be used in a duplicated 3x3 Latin square design to evaluate feeding behavior, ruminal nutrient degradability, rumen pH, ruminal fermentation, and ruminal microbiota to study the ruminal metabolism during and after the adaptation period. (AU)