In bachelor thesis is described how heat stress occurs in chicken. Stress occurs when ambinet temperature increases beyond the termoneutral temperature. There are two types of heat stress – acute and chronic. They differ in duration and intensity. How heat stress affects behavior and metabolism (oxidative stress, acid base imbalance, decreased thyroid hormone activity) is also presented. It was found out that heat stress in broilers causes lose in weight, increased oxidative stress, oxidation of fats and proteins, increased sweating, faster breathing, increased heart rate, less moving, spread wings and shorter shelf life of meat. Furthermore, the process of glycolysis and conversion of muscle into meat is described, which occurs in three stages – before rigor, rigor and stage of meat softening. There are three different qualities of meat (normal, PSE, DFD), which differ in their morphological, microscopic and physico-chemical characteristics. Furthermore, caution is exposed in the preparation and processing of chicken meat. Lastly, different ways of reducing heat stress are presented.
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