Magdalena Krauze
The possibility of using selected enzymatic indicators in the assessment of stress response turkey hens for fattening neutralized by the addition L-carnitine or choline 
zeszyt 377, ss. 103
Change in the level of biochemical and morphological blood markers and enzyme activity reflects undergoing changes of metabolic status and suggests the outcomes, such as physiological and morphological cellular alterations, impaired immunity, decrease in productivity, incidence of pathological symptoms, and even death. 
The aim of this study was to determine whether it was possible to used rarely used biochemical markers along with traditional indicators to diagnose environmental stress. In addition, it was reasonable to assess the impact of L-carnitine and choline as factors mitigating stress in rearing turkey hens. 
In two experiments, each by 480 female turkeys intended for slaughter 
(5 groups of 16 individuals in 6 replicates). In the experiment 1, L-carnitine and choline were administered in two different doses. In the experiment 2, caffeine was treated as an intermittent stress, and  was used both as a separate experimental factor as well as in combination with L-carnitine or choline. The collected blood from turkeys and pectoral muscle tissue and the liver, the activity/concentration of biochemical markers (enzymatic and non-enzymatic) and haematological indices. Also analyzed the effectiveness of selected rearing parameters.
The results of the experiment 1 indicate that a higher dose of L-carnitine and a lower dose of choline. It has been observed that caffeine adversely affects the activity of marker enzymes, and the way indicators of lipid, energetic and mineral transformations fluctuate, which may be correlated with a negative impact of this factor on metabolism and the state of cellular membranes. It may be presumed that a much better effect visible in the picture of biochemical transformations in the experiment 2, achieved after the application of L-carnitine and choline might have been the result of their beneficial effect on these processes, especially lipid metabolism under stress.  
It was found that L-carnitine administered at a dose of 25 mg/dm3 and choline – 200 mg/dm3 of water are able to reduce the level of GLU, TG, FFA fraction increases HDL cholesterol, and decrease the ratio of H: L Caffeine induces stress birds, which is manifested to increase the proportion of H : L ratios and an increase in protein-tional changes, GLU, FFA, TG and reduced CHOL content and share their HDL. The studies revealed that rarely analyzed enzymatic indicators may be used in the diagnosis of stress in the animals, as reliable markers for assessing the stress response, and the L-carnitine and choline may be used as factors mitigating the effects of stress.