Rhinos existed back in prehistoric times and when flourished in thousands, moving into diverse habitats across Africa, Asia, Europe and North America. Today, due to poaching and habitat loss, few remain. Since 1970 alone, the rhinoceros population has declined by approximately 90 percent, in line with the American Wildlife Foundation. As of 2010, you can find five type of rhinos totaling approximately 24,500 within the wild and 1,250 in captivity, reports the International Union for Conservation of Nature (IUCN). The White Rhino is under threat of extinction and also the other four species are saved to the verge of extinction. The five remaining species are: Enteric Arthritis - a form of chronic inflammatory arthritis associated with inflammatory bowel disease (IBD), the two most famous of which are ulcerative colitis and Crohn's disease. About one in five patients with Crohn's or ulcerative colitis develop enteric arthritis. The most common site affected by inflammation is the peripheral (limbs) joints and spine. A cortisol blood test is carried out to discover the cortisol hormone level in the blood. Cortisol assists one's body in metabolic process and stress management. The levels of cortisol inside the blood may vary as a consequence of several factors like stress, infection, injury and strenuous activities. The levels of cortisol usually vary throughout the length of the afternoon. In the morning, it can be generally increased, at night and during sleep, its level is often low. Its level, however, may continue with the person's sleeping habits. Those who sleep within the daytime and therefore are awake during the night, might have reversed cortisol level patterns also.