Military working dogs (MWDs) are often required to operate in dangerous or extreme environments, to include hot and humid climate conditions. These scenarios can put MWD at significant risk of heat injury. To address this concern, a two-compartment (core, skin) rational thermophysiological model was developed to predict the temperature of a MWD during rest, exercise, and recovery. The Canine Thermal Model (CTM) uses inputs of MWD mass and length to determine a basal metabolic rate and body surface area. These calculations are used along with time series inputs of environmental conditions (air temperature, relative humidity, solar radiation and wind velocity) and level of metabolic intensity (MET) to predict MWD thermoregulatory responses. Default initial values of core and skin temperatures are set at neutral values representative of an average MWD; however, these can be adjusted to match known or expected individual temperatures. The rational principles of the CTM describe the heat exchange from the metabolic energy of the core compartment to the skin compartment by passive conduction as well as the application of an active control for skin blood flow and to tongue and lingual tissues. The CTM also mathematically describes heat loss directly to the environment via respiration, including panting. Thermal insulation properties of MWD fur are also used to influence heat loss from skin and gain from the environment. This paper describes the CTM in detail, outlining the equations used to calculate avenues of heat transfer (convective, conductive, radiative and evaporative), overall heat storage, and predicted responses of the MWD. Additionally, this paper outlines examples of how the CTM can be used to predict recovery from exertional heat strain, plan work/rest cycles, and estimate work duration to avoid overheating.

中文翻译：

---

一种模拟军用工作犬温度响应的犬热模型

军用工作犬 (MWD) 通常需要在危险或极端环境中作业，包括炎热和潮湿的气候条件。这些情况会使 MWD 面临热损伤的重大风险。为了解决这个问题，开发了一个两室（核心、皮肤）合理的热生理模型来预测休息、运动和恢复期间 MWD 的温度。犬热模型 (CTM) 使用 MWD 质量和长度的输入来确定基础代谢率和体表面积。这些计算与环境条件（气温、相对湿度、太阳辐射和风速）和代谢强度水平 (MET) 的时间序列输入一起使用，以预测 MWD 体温调节反应。核心和皮肤温度的默认初始值设置为代表平均 MWD 的中性值；但是，这些可以调整以匹配已知或预期的个人温度。CTM 的合理原理描述了通过被动传导从核心区室的代谢能量到皮肤区室的热交换，以及对皮肤血流和舌头和舌组织的主动控制的应用。CTM 还在数学上描述了通过呼吸（包括喘气）直接向环境损失的热量。MWD 毛皮的隔热性能也用于影响皮肤的热量损失和环境热量的吸收。本文详细描述了 CTM，概述了用于计算传热途径（对流、传导、辐射和蒸发）的方程，整体储热，以及 MWD 的预测响应。此外，本文还概述了如何使用 CTM 预测从劳累性热应变中恢复、计划工作/休息周期和估计工作持续时间以避免过热的示例。