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RESEARCH ARTICLE (Open Access)

Effect of diurnal feeding times and sources of energy supplementation to optimise rearing of F1 Angus × Nellore young bulls

Andressa Scholz Berça https://orcid.org/0000-0001-6039-2091 A * , Abmael da Silva Cardoso B , Natália Vilas Boas Fonseca A , Dennis P. Poppi C , Luís Orlindo Tedeschi D , Isabela Rita Coletti Micheletti A , Willi Rocha Meireles A , Ana Cláudia Ruggieri A and Ricardo Andrade Reis A
+ Author Affiliations
- Author Affiliations

A Department of Animal Sciences, Sao Paulo State University, Jaboticabal, SP 14884-900, Brazil.

B Range Cattle Research and Education Center, University of Florida, Ona, FL 33865, USA.

C School of Agriculture and Food Sciences, The University of Queensland, Gatton, Qld 4343, Australia.

D Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USA.

* Correspondence to: dessaberca@yahoo.com.br

Handling Editor: Alex Bach

Animal Production Science 63(6) 579-595 https://doi.org/10.1071/AN22075
Submitted: 26 February 2022  Accepted: 14 November 2022   Published: 11 January 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context: Energy supplementation with highly fermentable carbohydrates can be a strategy to maximise the efficiency of nitrogen use (ENU) from high-nutritional value forages.

Aims: The study aimed to investigate the independent or associated effects of two diurnal feeding times (0900 or 1700 hours) with two sources of energy supplementation (corn or citrus pulp) in the growing of F1 Angus × Nellore young bulls on palisade grass pastures, and their implications on the forage chemical composition, nutrient intake and digestibility, ENU, microbial protein synthesis, animal performance, and gain per area.

Methods: There were 36 bulls used as experimental animals, with initial bodyweight (BW) of 290 ± 5 kg, and 32 similar bulls were used in a put-and-take system to maintain sward characteristics. The experiment was conducted in a complete randomised design with four treatments and three replications (paddocks). The treatments consisted of energy supplementation at 0.3% BW with corn or citrus pulp fed at 0900 or 1700 hours for four periods of 28 days. For evaluation of ruminal and blood parameters, ENU, intake, and nutrient digestibility, eight ruminal cannulated 1/2 Aberdeen Angus × 1/2 Nellore young bulls were used, with 280 ± 7 kg of initial BW, distributed in a 4 × 4 double Latin square design, consisting of four periods and four treatments.

Key results: Supplementation at 0.3% of BW with corn or citrus pulp at 0900 or 1700 hours can reach up to 1.06 kg/day of young bulls reared on palisade grass pastures fertilised with 180 kg nitrogen/ha/year and managed at 25 cm of height compared with corn-based supplements. There were no effects on microbial protein synthesis or its efficiency.

Conclusions: Citrus pulp can be used as an alternative energy source to corn, because it has the same potential for animal performance, ENU and microbial protein synthesis in tropical pastures with a high proportion of soluble protein, and structural and non-fibrous carbohydrates with high dry matter digestibility.

Implications: Supplementing grazing beef cattle at 0.3% BW with corn or citrus pulp in the morning or afternoon is an efficient nutritional strategy to improve animal performance.

Keywords: animal performance, beef cattle, citrus pulp, corn, microbial protein, palisade grass, ruminal parameters, supplementation time.


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