Rat thermal and behavioural respones to food reward magnitudes

I used infrared thermography (IRT) to collect continuous surface temperature measurements of 18 male and 18 female rats (Rattus norvegicus) to investigate the possible application of IRT in positive animal welfare assessments ( whether IRT can identify as well as quantify positive welfare states). Three groups of rats were given increasing magnitudes of rewards (zero, one and three sweet cereal pallets or Cheerios) to determine a potential proportionality thermal response of rats to the increasing intensity of a positive stimuli. Rats were placed in a test arena to which they were habituated and filmed for 30 seconds before and 30 minutes after being exposed to the designated treatments, to obtain individual baseline temperatures and changes in surface temperature as well as concurrent behaviours in response to food reward.本研究采用红外热成像（infrared thermography, IRT）技术，对18只雄性与18只雌性褐家鼠（Rattus norvegicus）开展连续体表温度数据采集，旨在探究IRT在动物正向福利评估中的潜在应用价值——即IRT能否识别并量化动物的正向福利状态。实验设置三组大鼠，分别给予递增剂量的奖励刺激（0块、1块及3块甜味谷物零食或Cheerios），以分析大鼠的热响应是否与正向刺激强度呈比例关系。将大鼠放置于预先适应的测试场域中，在接受指定处理前30秒与处理后30分钟分别进行录像，以此获取个体基础体表温度、体表温度变化数据，并同步记录其针对食物奖励的行为反应。