英语翻译mounting empirical evidence suggests that many animal experiments are performed callously without any heed to the discomfort or pain that laboratory mammals endure.
问题描述：
英语翻译
mounting empirical evidence suggests that many animal experiments are performed callously without any heed to the discomfort or pain that laboratory mammals endure.
答
整句话书面一点的说法是：
越来越多的经验证据表明,动物实验是在无视动物所承受的不适或痛苦中冷酷地进行的.
直白一点就是说：越来越多的经验证据表明,做动物实验是很冷酷的,根本不能留意（不会在意）哺乳动物作为实验对象所需要承受的不适或者痛苦.
perform的意思是“施行,做”,被动语态
heed to的意思是“留意到,在意”
整句话到底想说“做动物实验的人是非常残忍的”呢,还是想说“人必须要非常残忍才能做的了动物实验”呢,要看上下文而定.估计应该想说的是前者.