Zkrmování výlisků ostropestřce mariánského u nosnic na začátku snášky

This thesis is aimed at studying the effect of the addition of milk thistle (Silybum marianum) seed cakes to the diet on metabolism, liver function and performance of laying hens at the beginning of laying. In the experiment, the results were compared between a group of laying hens, which were fed with the basic feed mixture without the addition of milk thistle seed cakes with the experimental group with the addition of milk thistle seed cakes in the feed mixture. It was situated 30 hens breed ISA Brown into the experiment, divided into two groups. The first group was experimental with the addition of milk thistle seed cakes (7 % in the mixture), and the second group was a control. The experiment evaluated egg laying, egg weight, food consumption and the animal weight. During the experiment, blood was twice collected from animals for biochemical examination focusing on the parameters of liver profile. The results of the experiments didn´t show any effects of feeding milk thistle seed cakes on the body weight of laying hens. By evaluating the performance parameters of the laying hens it showed a significantly lower egg laying, but also showed a lower consumption of feed (P < 0.05). At the same time, the data found higher weigh of eggs (P < 0.01) in this group, but the egg production was significantly lower than in the control group. During the examination of biochemical parameters of blood there was a significantly higher concentration of bilirubin, uric acid and cholesterol (P < 0.05) in the blood plasma of laying hens fed by the addition of milk thistle seed cakes. At the second sampling (approximately 2 months) the laying hens that were fed with milk thistle seed cakes have consistently higher concentration of cholesterol (P < 0.05) and lower activity of dehydrogenase, creatine kinase (P < 0.05) and uric acid (P < 0.01) in the blood. In the experiment there was no clear positive or negative effects of the milk thistle seed cakes on the performance parameters and biochemical profile of the blood plasma