Saddle Saddle The saddle is a supportive structure for a rider or other load, fastened to an animal's back by a girth. The most common type is the equestrian saddle designed for a horse. However, specialized saddles have been created for oxen, camels and other creatures. It is not known precisely when riders first began to use some sort of padding or protection, but a blanket attached by some form of surcingle or girth was probably the first "saddle", followed later by more elaborate padded designs. The solid saddle tree was a later invention, and though early stirrup designs predated the
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