Longeing piece of twine or rope, though for a very skittish young horse they also can be thrown up over the top of the saddle and tied down in that fashion. A surcingle or roller is a padded band that straps around the horse's girth area, and has rings around on its side for side reins, or long reins or other training equipment, such as an overcheck. It may also be used on a young horse to get it used to girth pressure. It may be used with or without an English saddle underneath. Side reins are usually used for more
Animal testing on frogs which reaches its reproductive age in five months rather than one to two years (as in "X. laevis"), facilitating faster studies across generations. The genome sequence of "X. tropicalis" was scheduled to be completed by 2015 at the latest. Frogs are widely used in classroom dissections and teaching exercises. Animal testing on frogs Frogs have been used in animal tests throughout the history of biomedical science. Eighteenth-century biologist Luigi Galvani discovered the link between electricity and the nervous system through studying frogs. The African clawed frog or platanna, "Xenopus laevis", was first widely used in laboratories in pregnancy assays in