Situations Leading to Oxidative Stress in Dairy Cattle

Free radicals are normally produced by living organism, at controlled production rate they perform physio-logical functions as signal transduction molecules. However, situations leading to an overproduction that surpasses antioxidant capacity creates oxidative stress. Consequently, damage to the cell membrane, pro-tein, DNA and cell death are observed. Dairy cattle are susceptible to oxidative stress. Situations such as infections, metabolic disorders and heat stress are known to cause oxidative stress in cattle by depleting body antioxidants concentrations or by increasing endogenous free radical production. The organism re-sponse to oxidative stress by activating cell factors that after evaluating the damage to cell, a repair or death signal will be programmed. The objective of this review is to empower the reader with knowledge related to oxidative stress and to provide information on the situations leading to this type of stress and the cellular response to it in dairy cattle.