Advancing a causal loop diagram of ruminant feeding behavior: a step forward in modelling intake regulation
Description
Daily feeding behavior (FB) in ruminants emerges from interacting physiological, dietary, managerial, and environmental drivers (Albright, 1993). Systems thinking (ST) provides a methodological base to conceptualize this complex biological phenomenon by identifying the interaction between variables (Tedeschi et al., 2025). A preliminary causal loop diagram (CLD) had previously identified the main feedback structures underlying FB, but several dynamic structures were not fully explicated, particularly those linking FB with nutrient inflow, nitrogen efficiency, and nitrogen dynamics as well as recycling (Canossa et al., 2025). This limitation is relevant to move toward a mathematical formulation of the conceptual model. A systems thinking approach was applied through problem articulation, system boundary definition, literature review, and extraction of variables and causal relationships from more than 90 publications. The previous CLD was refined by integrating short-term ingestive regulation with medium-term metabolic responses and external constraints. Where available, variables and causal links were specified using literature-derived quantitative evidence, so that the feedback structure is aligned with measurable relationships among key variables. The refined CLD highlights that FB is a determinant of nutrient inflow, because meal pattern and eating rate regulate the timing and quantity of substrates entering rumen fermentation. This is relevant for nitrogen dynamics, since dietary N intake, ruminal ammonia production, microbial N synthesis, urea-N recycling, and urinary and fecal N excretion depend on nutrient entry and absorption/transformation within the digestive system (Li et al., 2019). Thus, the expanded CLD provides a conceptual basis for linking feeding behavior to intake dynamics and for developing a quantitative model of nutrient inflow and nitrogen flows, supporting the evaluation of strategies to improve nitrogen use efficiency and reduce N excretion.
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Institutions
- Università Cattolica del Sacro CuoreLombardy, Milan
Categories
Additional Metadata for UCSC Datasets
| Campus | Piacenza |
| Scientific Disciplinary Area (until 2024) | AGR/18 - Nutrizione e alimentazione animale |
| Scientific Disciplinary Area (after 2024) | AGRI-09/B - Animal Nutrition and Feeding |
| Keywords | Modeling and Simulation, Agricultural and Biological Sciences |