Modelling ruminant grazing systems based on native grasslands. 2. Evaluation of the animal dynamics module
Abstract
Ecological intensification of beef cow-calf systems on native grasslands requires quantitative tools that link herbage condition, animal physiology, and management at the whole-farm level. We present and evaluate the animal dynamics module of PAmpa Sustainable grAzing Livestock Management (PASpALuM), a farm-scale model developed for high-diversity Pampas grasslands. The module simulates individual animal herbage intake, energy balance, BW, body condition score (BCS), and reproduction as functions of herbage height, management practices, and weather. Herbage height and BCS are used as key, farmer-measurable state variables that integrate sward structure, intake regulation, metabolic status, and reproductive performance. Output is probabilistic as a result of stochasticity in animal input data and the parameters governing pregnancy. Model performance was evaluated using (i) experimental data on herbage intake and daily weight gain of heifers under contrasting herbage allowances during two single seasons (n = 16), and (ii) on-farm data from six cow-calf farms to assess cow BW, BCS and pregnancy, and herbage height during one mating season. Herbage height and mass were simulated by the herbage module presented in an accompanying paper. Simulated herbage intake showed strong agreement with the experimental data, resulting in mean absolute difference (MAD) and RMSE values of 0.44 and 0.52 kg DM/animal per day, respectively. MSD was dominated by 'lack of correlation' (79%), whereas…
Read the paper
Related studies
- Chaos and quantum thermalization
- The Dalton quantum chemistry program system
- Clinical phenotypes of delirium during critical illness and severity of subsequent long-term cognitive impairment: a prospective cohort study
- Cord Blood Leptin and Adiponectin as Predictors of Adiposity in Children at 3 Years of Age: A Prospective Cohort Study
- Quantitative metabolomics by H-NMR and LC-MS/MS confirms altered metabolic pathways in diabetes
- Comparative risk of genital infections associated with SGLT2 inhibitors: A real-world retrospective cohort study
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.