Gabriele Voltareli da Silva, Rolando Pasquini Neto, Mariana Nunes Vieira de Melo, Luiza Budasz de Andrade, Althieres José Furtado, Ester Costa Fabrício, Analisa Vasques Bertoloni, Annelise Aila Gomes Lobo, Flavio Perna Junior, Sérgio Raposo de Medeiros, Alexandre Berndt, R. T. Nassu, André de Faria Pedroso, Patrícia Perondi Anchão de Oliveira, Angélica Simone Cravo Pereira, Paulo Henrique Mazza Rodrigues
• We evaluated Nellore steers’ muscle development and meat quality traits as well as the methane (CH 4 ) emissions intensity per kg of carcass. • Five tropical pasture-based beef cattle production systems were analyzed. • Carcass and meat quality traits observed are positively influenced by well-managed intensified systems. • This increased efficiency allows CH 4 emission intensities, confirming their potential as a viable sustainability system to avoid pasture degradation processes. This study evaluated the effects of five pasture-based production systems on the carcass and meat quality traits, as well as the methane (CH 4 ) emissions intensity of male Nellore steers per kg of carcass under tropical conditions. Over two years (2019-2021), uncastrated male steers (three/year/experimental spatial unit) were randomly assigned to five treatments (with two replicates): 1) degraded pasture without nitrogen (N) fertilization (DP0); 2) silvopastoral with 200 kg N ha -1 (SP200); 3) rainfed pasture with 200 kg N ha -1 (RP200); 4) rainfed pasture with 400 kg N ha -1 (RP400); and 5) irrigated pasture with 600 kg N ha -1 (IP600). Animals grazed exclusively, receiving water and mineral-protein supplement ad libitum until being stunned by the Brazilian-approved method cranial concussion, followed by exsanguination, without electrical stimulation. The carcass and meat quality traits observed are positively influenced by intensification. Specifically, IP600, RP400 and RP200 demonstrate a clear benefit in improving RA, BFT, LCCW, CEP and FT (including HEP, FEP and spareribs), and Bones (expressed as kg carcass -1 and %); while SP200 and DP0 restricted the growth rates and muscle development of the animals due to the competition between the trees and the pasture and lack of fertilization, respectively. For CH 4 emission intensities (per kg of carcass), SP200 and DP0 exhibited the highest emissions without proportional production gains, while IP600, RP400, and RP200 showed the lowest values. Well-managed intensified pasture-based systems consistently achieved lower CH 4 emission per unit of product than those observed in DP0, confirming their potential as a viable sustainability system.