Interpretive Summary: Predicting dry matter intake using conceptual models for cattle kept under tropical and subtropical conditions
By: Anne Wallace
Dry matter (DM) intake prediction models are an invaluable tool that can help to increase efficiency and production in cattle. However, there is a need to better predict the voluntary dry matter intake (VDMI) of cattle under tropical and subtropical conditions. Various predictive models exist, including empirical and mechanistic models. The use of such models, which were generally designed with temperate environments in mind, tend to be difficult to apply to (sub)tropical environments – e.g., they have less accuracy and precision. However, conceptual mathematical models (CMM) may be a better alternative to predict VDMI in the (sub)tropics.
Currently, CMM has been well studied in temperate conditions but are lacking for (sub)tropical conditions. In this study published in the September 2019 issue of the Journal of Animal Science, the authors’ objective was to determine if CMM modeling could accurately predict VDMI of cattle in (sub)tropical conditions. They hypothesized that CMM modeling would have the ability to predict VDMI accurately.
The Conrad Conceptual Mathematical Model (C1) and Mertens Conceptual Mathematical Model (M1) were used in this study. Original models and modified models (C2, C3, C4 and M2, M3, and M4) were evaluated for a total of eight studied models. Of these, the C1, C2, and M4 models were found to be the most effective in predicting VDMI of cattle in (sub)tropical conditions.
Overall, this study suggests that CMM models may be more useful in predicting VDMI in cattle in (sub)tropical environments. Further studies into different CMM or with modified Conrad or Mertens CMMs may be warranted to determine which are most ideal to apply to cattle raised under (sub)tropical conditions.
To view the article, visit the Journal of Animal Science.