Title:	From empirical evidence to canonical modeling: an agent-based model of the Brazilian cattle trade network.
Authors:	SILVA, R. F. M. da OLIVEIRA, S. R. de M. BERGIER, I.
Affiliation:	ROOSEVELT FABIANO MORAES DA SILVA, UNIVERSIDADE ESTADUAL DE CAMPINAS; STANLEY ROBSON DE MEDEIROS OLIVEIRA, CNPTIA, UNIVERSIDADE ESTADUAL DE CAMPINAS; IVAN BERGIER TAVARES DE LIMA, CNPTIA.
Date Issued:	2026
Citation:	Agriculture, v. 16, n. 12, 1254, June 2026.
Description:	The beef production chain plays a strategic role in Brazilian and global agri-food systems and faces growing demands for sustainability, transparency, and traceability. Building on official Animal Transit Guide (GTA) records from Mato Grosso do Sul, Brazil, this study examines whether a parsimonious agent-based model (ABM) can generate the main structural signatures of an observed cattle-trade network. The empirical benchmark is a directed and weighted network with 20,827 nodes and 258,120 weighted edges. The ABM represents producers and slaughterhouses as spatial agents connected by trade decisions based on three mechanisms: destination attractiveness, defined as the accumulated pull of a slaughterhouse based on previous simulated throughput; geographic distance, representing spatial friction; and relational memory, representing the tendency to repeat previous commercial ties. Producer choice is formalized through a local utility function that combines attractiveness, distance penalty, and relational memory under capacity, sourcing-radius, and saturation constraints. In the simulated scenarios, the top-five slaughterhouses accounted for 38.49 ± 2.56% of throughput at reduced scale and 14.40 ± 0.65% at intermediate scale, while weighted mean distances were 11.94 ± 0.56 and 9.07 ± 0.39 model units, respectively. The model reproduced, in structural and mechanistic terms, the emergence of dominant hubs, the concentration of flows, and the bounded increase in transaction distance with connectivity around the empirical threshold of kw ≈ 256. Sensitivity analyses indicated that attractiveness increases concentration, distance localizes transactions, and relational memory can stabilize repeated ties when recurrent activation is represented. Rather than reconstructing individual transactions, estimating policy impacts, or identifying a unique parameter vector, the model provides a generative explanation of how local trade rules can produce macro-level network patterns consistent with the observed cattle-trade regime. These findings support future prospective analyses of cattle governance, traceability, and sustainability within the broader context of Livestock 4.0.
Keywords:	Comercialização de gado Polos de abate Fricções espaciais Persistência relacional Rastreabilidade digital Governança da cadeia de suprimentos Conectividade ponderada Sistemas complexos Livestock commercialization Slaughterhouse hubs Spatial frictions Relational persistence Digital traceability Supply-chain governance Weighted connectivity Complex systems
ISSN:	2077-0472
DOI:	10.3390/agriculture16121254
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CNPTIA)