Intake and digestibility of Marandu grass pastures and energy supplementation on F1 Angus-Nelore growing

• Grant number: 20/08154-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): September 01, 2020
• Effective date (End): August 31, 2021
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Ricardo Andrade Reis
• Grantee: Isabela Rita Coletti Micheletti
• Home Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Beef cattle represents a relevant portion of the Brazilian economy, being characterized by extensive cattle production. However, the search for increased productivity demands the incorporation of technologies and an intensive production system by ranchers. In this sense, the energy supplementation associated with Marandu grass pastures fertilized with 180 kg of N/ha/year is an efficient mechanism, as it promotes a greater supply of forage with high nutritional value, enhancing animal performance and promoting greater contribution and digestibility of nutrients. An alternative energy supplement to corn in the nutrition of ruminants is the citrus pulp, which presents high digestibility of the fibrous fraction, improving the efficiency of use of the soluble protein of the forage. The objective of the work is to evaluate the isolated and/or associated effects of two supply times (9 am and 5 pm) of two sources of energy supplements (corn and citrus pulp) in the rearing of F1 Angus-Nelore bulls in Marandu grass pastures, and its implications for nutrient intake and digestibility. The experiment will be conducted in the FCAV / UNESP Forage Sector, during the rearing phase of animals kept in pastures of Urochloa brizantha cv. Marandu (Marandu grass). Eight bulls ½ blood Aberdeen Angus x ½ blood Nellore, cannulated in the rumen, with an initial average weight (PMI) of 280 kg will be used, distributed in a double Latin square 4x4 design. The treatments will consist of: 1 - energy supplementation 0.3% of body weight (BW) with corn supplied at 9:00 am; 2 - energy supplementation 0.3% of the CP with citrus pulp, delivered at 9:00 am; 3 - 0.3% PC energy supplementation with corn supplied at 5:00 pm; 4 - 0.3% PC energy supplement with citrus pulp, delivered at 5 pm.