Effects of hydrocortisone on substrates of energy metabolism in alpacas

Principal investigators:

Cebra, C.K., S.J. Tornquist and S.A. McKane
American Journal of Veterinary Research 63: 1269-1274, 2002

High levels of blood sugar are sometimes found in alpacas under stress. The release of corticosteroids in response to stress is thought to be one factor which contributes to elevated blood sugar. Stress hormones may also increase blood lipids and may result in fatty liver disease. However the influence of stress hormones on blood sugar and lipids in alpacas and the ability of alpacas to control rising blood sugar and lipids by release of insulin has not been adequately investigated. In this study the stress hormone hydrocortisone was injected into alpacas to mimic a condition of stress. The investigators measured blood sugar, blood lipids and insulin before and after injection of hydrocortisone. They found that blood lipids were adequately controlled by a rise in the alpacas' own insulin level. By contrast, the insulin produced by the alpacas was not sufficient to control the rise in blood sugar that occurred in response to administration of the stress hormone cortisol. Injection of insulin was required to successfully reduce blood sugar suggesting that insulin treatment would probably be helpful in lowering blood sugar in stressed alpacas.