Surcingle the withers area. It usually has padding to relieve pressure on the horse's spine. A variation of this design is used for equestrian vaulting. Many trainers first teach a young horse to accept girth pressure by strapping on a surcingle before a saddle and girth. The surcingle is commonly used for longeing, often as a base from which to attach training equipment such as side reins, overcheck, lauffer reins (sliding side reins), or chambons. A surcingle is also important in long lining or ground driving, as it provides rings for the long reins to run through. Double longeing, using two
Animal testing on invertebrates Animal testing on invertebrates Most animal testing involves invertebrates, especially "Drosophila melanogaster", a fruit fly, and "Caenorhabditis elegans", a nematode. These animals offer scientists many advantages over vertebrates, including their short life cycle, simple anatomy and the ease with which large numbers of individuals may be studied. Invertebrates are often cost-effective, as thousands of flies or nematodes can be housed in a single room. With the exception of some cephalopods, invertebrate species are not protected under most animal research legislation, and therefore the total number of invertebrates used remains unknown. Research on invertebrates is the foundation for current understanding of