Researchers have found that laboratory mice moved by tail handling rather than by tunnel are less responsive to reward which has implications for designing and interpreting scientific studies. Here is the original research https://www.nature.com/articles/s41598-018-20716-3  and here is the original press release https://www.ncl.ac.uk/press/articles/archive/2018/02/mousehandling/ Today the UK government releases its statistics listing the tapes of animals used in research and the types of work (procedures) done with them. http://www.understandinganimalresearch.org.uk/news/communications-media/animal-research-numbers-in-2018/