Threatened arthropods United States, and IUCN Red List for international purposes. Only a tiny fraction of the planet's endangered arthropods are formally recognized as such, as no one has ever evaluated the conservation status of the vast majority of arthropod species. It is difficult to estimate the total number of endangered arthropod species, since many of the taxa themselves have not been recorded. For example, in North America the estimated number of insect species exceeds 163,000, of which only about two thirds are taxonomically known. An even greater discovery awaiting, over 72 percent of North American arachnids are yet to be named
Organ replacement in animals cats, have high enough blood component values, and have no infectious diseases. One donation could be used by up to two animals. Policy regarding how donor animals are treated varies. In April, 2014, a veterinarian office in Fort Worth Texas, was accused of keeping dogs that had been presumed to have been euthanized, and using the animals for blood withdrawal. Open-heart surgery for dogs requires a six- to eight-person team to carefully monitor the patient before and during the invasive surgery. The entire surgery lasts five hours, during which time the dog is connected to a blood oxygenator and the