Department of Animal Science, University of California, Davis, CA 95616, USA.
J Anim Sci. 2011 Dec;89(12):3973-82. doi: 10.2527/jas.2011-3913. Epub 2011 Aug 5.
The overall objective of this work was to develop empirical equations from a meta-analysis study to be used to implement initial values in a mechanistic heat balance model. The meta-analysis was conducted to 1) develop prediction equations for sweating and respiration rate (SR, g·m(-2)·h(-1) and RR, breaths·min(-1), respectively) based on skin and body temperature (T(s) and T(b), °C, respectively) for different breed types: Bos indicus, Bos taurus, and their crossbreds, and 2) evaluate the fit of existing SR equations and the SR and RR equations (from objective 1) against independent data sets. Fourteen studies were collected for the SR analysis, 12 for fitting and 2 for evaluation. The fitted SR equations (Thompson model) for the 3 breeds types were B. indicus, SR = 0.085e(0.22·T(s)); B. taurus, SR = 0.75e(0.15·T(s)); and crossbreds, SR = 0.015e(0.25·T(s)). Twenty-three studies were collected for the RR analysis, 20 for fitting and 3 for evaluation. The fitted RR equations for the 3 breed types were B. indicus, RR = -1,660 + 43.8·T(b); B. taurus, RR = -1,385 + 37·T(b); and crossbreds, RR = -2,226 + 59·T(b). Three SR equations (Maia, McArthur, and Gatenby models) from the literature were evaluated against the Thompson model using the 14 studies. The McArthur model predicted SR within the correct range, but with an increased slope bias because the equation was linear and not the correct shape. The Maia model overpredicted SR for all breed types with the greatest overprediction being for crossbreds. The Gatenby model overpredicted SR for B. taurus (root mean square error of prediction = 506 g·m(-2)·h(-1)), but was the best predictor for B. indicus. The Thompson model overpredicted SR for B. indicus (root mean square error of prediction ranged from 134 to 265 g·m(-2)·h(-1)), but was the best predictor for B. taurus and crossbreds. The Thompson model was a good predictor for RR across all breed types. The meta-analysis showed that the Thompson model outperformed previous models for both RR and SR with the exception of the SR of B. indicus, which was best predicted by the Gatenby model.
这项工作的总体目标是从荟萃分析研究中开发经验方程，以便在机理热平衡模型中使用初始值。进行荟萃分析以 1）根据皮肤和体温（分别为 T(s)和 T(b)，°C）为不同品种类型：印度牛、瘤牛及其杂种牛开发出汗和呼吸率（SR，g·m(-2)·h(-1)和 RR，呼吸·min(-1)）的预测方程，以及 2）评估现有 SR 方程和 SR 和 RR 方程（来自目标 1）对独立数据集的拟合效果。为 SR 分析收集了 14 项研究，为拟合收集了 12 项，为评估收集了 2 项。为 3 个品种类型拟合的 SR 方程（Thompson 模型）为：印度牛，SR = 0.085e(0.22·T(s)); 瘤牛，SR = 0.75e(0.15·T(s)); 杂种牛，SR = 0.015e(0.25·T(s))。为 RR 分析收集了 23 项研究，为拟合收集了 20 项，为评估收集了 3 项。为 3 个品种类型拟合的 RR 方程为：印度牛，RR = -1,660 + 43.8·T(b); 瘤牛，RR = -1,385 + 37·T(b); 杂种牛，RR = -2,226 + 59·T(b)。使用 14 项研究，对文献中的三个 SR 方程（Maia、McArthur 和 Gatenby 模型）进行了与 Thompson 模型的评估。McArthur 模型在正确范围内预测了 SR，但斜率偏差较大，因为该方程是线性的，而不是正确的形状。Maia 模型对所有品种类型的 SR 都存在过高预测，对杂种牛的过高预测最大。Gatenby 模型对瘤牛的 SR 预测过高（预测均方根误差=506 g·m(-2)·h(-1)），但对印度牛是最佳预测模型。Thompson 模型对印度牛的 SR 预测过高（预测均方根误差范围为 134 至 265 g·m(-2)·h(-1)），但对瘤牛和杂种牛是最佳预测模型。Thompson 模型对所有品种类型的 RR 都是一个很好的预测模型。荟萃分析表明，Thompson 模型在 RR 和 SR 方面均优于以前的模型，但印度牛的 SR 除外，Gatenby 模型对其预测效果最佳。
