Effects of nitrogen fertilization on protein and carbohydrate fractions of Marandu palisadegrass

Author(s)

Leite, Rhaony Goncalves ^[1] ; Cardoso, Abmael da Silva ^[1] ; Boas Fonseca, Natalia Vilas ^[1] ; Curvelo Silva, Maria Luisa ^[1] ; Tedeschi, Luis Orlindo ^[2] ; Delevatti, Lutti Maneck ^[1] ; Ruggieri, Ana Claudia ^[1] ; Reis, Ricardo Andrade ^[1]

Affiliation

^[1] Sao Paulo State Univ, Dept Anim Sci, BR-14884900 Jaboticabal, SP - Brazil

^[2] Texas A&M Univ, Dept Anim Sci, College Stn, TX 77843 - USA

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 11, n. 1 JUL 20 2021.
• Web of Science Citations: 0

Abstract

The effects of nitrogen (N) fertilization levels on protein and carbohydrate fractions in Marandu palisadegrass pasture {[}Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster] were investigated in a pasture over five years. The experimental design was completely randomized with four levels of N (0, 90, 180, and 270 kg N ha(-1), as urea) for five years, and with three replicates. The study was conducted in a continuously stocked pasture during the forage growing season (December to April) in a tropical region. The effects of N fertilization were similar across the five years. With increasing N fertilization, the concentrations of crude protein (CP) increased from 103 to 173 g kg(-1) (P<0.001), soluble fractions (Fraction A+B1) increased from 363 to 434 g kg(-1) of total CP (P=0.006); neutral detergent fiber (NDF) decreased from 609 to 556 g kg(-1) (P=0.037); indigestible NDF (P=0.046), potentially degradable neutral detergent fiber (P=0.037), and acid detergent fiber decreased (P=0.05), and total digestible nutrient (TDN) increased (P<0.001). Increasing N fertilization decreased the concentrations of Fraction C (P=0.014) and total carbohydrates (P<0.0001), and increased CP:organic matter digestibility (P<0.01). Concentrations of neutral detergent fiber free of ash and protein (P=0.003), indigestible neutral detergent fiber (P<0.001), neutral detergent fiber potentially degradable (P=0.11), CP (P<0.001), Fraction A+B1 (P<0.001), Fraction B2 (P<0.001), Fraction B3 (P<0.01), and non-structural carbohydrates differed (P<0.001) across years. Therefore, N fertilization can be used to increase CP, soluble protein, and TDN. (AU)

• FAPESP's process: 17/11274-5 - Decomposition of litter and greenhouse gases emission in Brachiaria grasses with increasing nitrogen fertilizer rates
• Grantee: Abmael da Silva Cardoso
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/16631-5 - Management strategies to reduce environmental impacts of beef cattle production systems
• Grantee: Ricardo Andrade Reis
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants
• FAPESP's process: 16/20485-7 - Use of DDGS in finishing feedlot cattle: intake and digestibility
• Grantee: Natalia Vilas Boas Fonseca
• Support Opportunities: Scholarships in Brazil - Scientific Initiation