Trace elements as related to growth and health in chickens

Abstract

This review summarizes the interest and the role oftrace element factors favouring body weight or bone growth and the immune response in poultry. The aim isto analyse consequences of supplementation in diets at levels corresponding or higher than the growth requirement for optimising performance of broilers; especially as the use of high dietary levels of trace elements is currently questioned to protect the environment. Cushows a slight growth promoting effect on chick growth when added at high concentrations, but Zn, Fe or Mndo not. However, such high dietary level can be deleterious for the environment in areas of intensive production. Zn, Se, Cu and Fe are essential elements for theimmune system but there is no clear evidence that high dietary levels stimulate the immune response Infection and coccidios is affect trace mineral metabolism and, therefore, may need nutritional adjustment. Ultra-traceelement (Al, Se, Bo, Cd, Cr, F, I, Si, V..) can be of nutritional importance for chicks submitted to some nutritional stress or, when in excess, can be toxic.