Hekman Jessica P, Karas Alicia Z, Dreschel Nancy A
Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, USA 01536.
Department of Animal Science, Pennsylvania State University, University Park, PA, USA 16802.
Appl Anim Behav Sci. 2012 Nov;141(3-4):149-157. doi: 10.1016/j.applanim.2012.08.007.
Identification of severe stress in hospitalized veterinary patients may improve treatment outcomes and welfare. To assess stress levels, in Study 1, we collected salivary cortisol samples and behavioral parameters in 28 healthy dogs hospitalized prior to elective procedures. Dogs were categorized into two groups; low cortisol (LC) and high cortisol (HC), based on the distribution of cortisol concentrations (< or ≥ 0.6 µg/dL). We constructed a stress research tool (SRT) based on three behaviors, (head resting, panting and lip licking) that were most strongly related to salivary cortisol concentrations. In Study 2, we collected salivary cortisol samples from 39 additional dogs, evaluated behavior/cortisol relationships, assigned each dog to an LC or HC group, and tested the ability of the SRT to predict salivary cortisol. Median (interquartile range) salivary cortisol concentrations were not different between Study 1 (0.43 µg/dL, 0.33 to 1.00 µg/dL) and Study 2 dogs (0.41 µg/dL, 0.28 to 0.52 µg/dL). The median salivary cortisol concentration was significantly lower (P ≤ 0.001) in LC versus HC dogs in each study; (Study 1 LC: 0.38 µg/dL, (0.19 to 0.44), n = 19, HC: 2.0 µg/dL, (1.0 to 2.8), n = 9, and Study 2 LC: 0.35 µg/dL, (0.25 to 0.48), n = 28, HC: 0.89 µg/dL, (0.66 to 1.4), n = 7). In Study 1, three behaviors were found to be associated with salivary cortisol concentrations. Duration of head resting was negatively associated with salivary cortisol (ρ = -0.60, P = 0.001), panting and lip licking were positively associated with cortisol (ρ = 0.39, P = 0.04, and 0.30, P = 0.05, respectively), Head resting (p = 0.001) and panting (p = 0.003) were also associated with LC/HC group assignment. In Study 2 dogs, the three behaviors correlated (but not significantly) with salivary cortisol concentration; of the three, only head resting was significantly associated with LC/HC group assignment (P = 0.03). The SRT derived from Study 1 was effective at prediction of salivary cortisol concentrations when applied to 20 min but not 2 min of behavioral data from Study 2. Additionally, we note that dexmedetomidine and butorphanol sedation more than 6 h prior to measurement was found to be significantly (P = 0.05) associated with lower salivary cortisol concentrations when compared to unsedated dogs. Our work offers support for eventual construction of a rating tool that utilizes the presence or absence of specific behaviors to identify higher salivary cortisol concentrations in dogs subjected to hospitalization, which may be tied to greater psychogenic stress levels. Future work to investigate the effects of stress on dogs and its mitigation in clinical situations may be approached by studying a combination o f parameters, and should consider the possible beneficial effects of sedatives.
识别住院兽医患者的严重应激状况可能会改善治疗效果和福利。为了评估应激水平，在研究1中，我们收集了28只择期手术前住院的健康犬的唾液皮质醇样本和行为参数。根据皮质醇浓度的分布（<或≥0.6µg/dL），将犬分为两组；低皮质醇（LC）组和高皮质醇（HC）组。我们基于与唾液皮质醇浓度最密切相关的三种行为（头部休息、喘气和舔唇）构建了一种应激研究工具（SRT）。在研究2中，我们从另外39只犬收集了唾液皮质醇样本，评估行为/皮质醇关系，将每只犬分配到LC或HC组，并测试SRT预测唾液皮质醇的能力。研究1的犬（0.43µg/dL，0.33至1.00µg/dL）和研究2的犬（0.41µg/dL，0.28至0.52µg/dL）的唾液皮质醇浓度中位数（四分位间距）没有差异。在每项研究中，LC组犬的唾液皮质醇浓度中位数显著低于HC组犬（P≤0.001）；（研究1，LC组：0.38µg/dL，（0.19至0.44），n = 19，HC组：2.0µg/dL，（1.0至2.8），n = 9；研究2，LC组：0.35µg/dL，（0.25至0.48），n = 28，HC组：0.89µg/dL，（0.66至1.4），n = 7）。在研究1中，发现三种行为与唾液皮质醇浓度相关。头部休息的持续时间与唾液皮质醇呈负相关（ρ = -0.60，P = 0.001），喘气和舔唇与皮质醇呈正相关（分别为ρ = 0.39，P = 0.04和0.30，P = 0.05），头部休息（p = 0.001）和喘气（p = 0.003）也与LC/HC组分配相关。在研究2的犬中，这三种行为与唾液皮质醇浓度相关（但不显著）；在这三种行为中，只有头部休息与LC/HC组分配显著相关（P = 0.03）。当将研究1得出的SRT应用于研究2的20分钟行为数据而非2分钟行为数据时，它能有效预测唾液皮质醇浓度。此外，我们注意到，与未镇静的犬相比，在测量前6小时以上使用右美托咪定和布托啡诺镇静与较低的唾液皮质醇浓度显著相关（P = 0.05）。我们的工作为最终构建一种评级工具提供了支持，该工具利用特定行为的有无来识别住院犬中较高的唾液皮质醇浓度，这可能与更高的心理应激水平相关。未来研究应激对犬的影响及其在临床情况下的缓解措施的工作，可以通过研究多种参数的组合来进行，并且应该考虑镇静剂可能产生的有益效果。
