CONTEXT

Drivers of change in farming systems are not static, they evolve. Yet, there is an underlying assumption in the literature that drivers of change are static.

OBJECTIVE

This paper seeks to understand how drivers of change in Ghana's backyard poultry farming system evolve within a calendar year and examine how different production strategies contribute to the incomes of farm households.

METHODS

A system dynamics model, comprising production, financial, consumption, and epidemiological modules, was developed, validated, and simulated for a 52-week period using a weekly timestep.

RESULTS AND CONCLUSIONS

Results of the loops that matter analysis showed that from the onset of the poultry production, disease prevention at different growth stages of the chicken (especially for day-old chicks) via vaccination is a critical driver of change that has a high but short-lived dominance. Beyond the grower stage, the changes in the unit price of eggs have a relatively higher and longer influence on production dynamics than changes in the unit price of poultry meat. Moreover, the results suggest that a focus only on meat production is the most profitable strategy compared to production strategies that focus only on egg production or a mix of egg and meat production.

SIGNIFICANCE

The findings of this paper extend the literature on drivers of change in the farming system by stressing the need to assess how these drivers evolve. The application of the loops that matter analysis in system dynamics modelling provides a framework for analysing the evolution of drivers of change in farming system.

中文翻译：

---

了解后院家禽养殖系统变化驱动因素的系统思维方法

语境

农业系统变化的驱动力不是静态的，而是不断发展的。然而，文献中有一个基本假设，即变革的驱动力是静态的。

客观的

本文旨在了解加纳后院家禽养殖系统变化的驱动因素如何在一个日历年内演变，并研究不同的生产策略如何为农场家庭的收入做出贡献。

方法

使用每周时间步长开发、验证和模拟了为期 52 周的系统动力学模型，包括生产、财务、消费和流行病学模块。

结果和结论

重要循环的结果分析表明，从家禽生产开始，通过疫苗接种在鸡的不同生长阶段（尤其是日龄雏鸡）预防疾病是变化的关键驱动力，这种变化具有高但寿命短支配地位。在种植者阶段之外，与禽肉单价的变化相比，鸡蛋单价的变化对生产动态的影响相对较高且持续时间较长。此外，结果表明，与仅关注鸡蛋生产或鸡蛋和肉类混合生产的生产策略相比，仅关注肉类生产是最有利可图的策略。

意义

本文的研究结果通过强调评估这些驱动因素如何演变的必要性，扩展了有关农业系统变化驱动因素的文献。循环关系分析在系统动力学建模中的应用为分析农业系统变化驱动因素的演变提供了一个框架。