Diarrhoeas in calves pose one of the most serious risks of calf management and cause economic losses. This is the reason why the objective of this paper was to evaluate in operation conditions the effect of selected dietary supplements on the frequency of diarrhoea occurrence in calves in the first stages of the period after weaning for milk nutrition. An agricultural enterprise where the workers were willing to cooperate and provide the biological material was selected: ZEFA Volary. In 2005 {--} 2008 calves were examined from 3 to 6 weeks of age on average. After filling the facility, the calves were divided into a control and experimental group. Blood and faeces samples were taken in selected calves of both groups and subsequently they were evaluated. The calves were treated with dietary supplements and their effect on the frequency of diarrhoeas was subsequently evaluated on the basis of the results of blood examination and recorded data (diarrhoea occurrence, diarrhoea duration, length of treatment, method and length of treatment, date of filling the facility and date of calf load-out, weight at the time of filling and load-out). The results were summarised and evaluated by a statistical programme (STATISTICA 7.0.). No statistically significant difference was proved between the particular calves of the control and experimental group. Based on our observations the effects of the treatment with dietary supplements on the frequency of diarrhoea occurrence in calves were not satisfactory in the first stages of the period after weaning for milk nutrition. But it is to state that some tendencies to reach a higher average weight gain were observed in calves of the experimental group in applied dietary supplements even though these results were statistically insignificant.

It is important to take care of calves and their health for good results in beef-raising. The aim of the work was to evaluate the effect of dietary supplements Lactovita and Biopolym on the frequency of diarrhoea occurrence in calves in the first stages of the period after weaning for milk nutrition. The experiment was conducted in farmers' cooperation Staré Hobzí, where Holstein Cattle are bred. Two groups of calves were made ? control and experimental group. In an experimental group dietary supplements to support active immunity were served according to the guideline. In case of diarrhoea occurrence the calves from experimental group were cured in the same way as the calves from control group. The occurrence of disorders during the period of experiment, method and length of treatment were recorded. Recorded data were summarised and statistically evaluated. The calves were examined from 29th February to 20th December. The results proved positive effect of dietary supplements Lactovita and Biopolym, but these results were statistifically insignificant. It is assumed that in case of studying bigger groups the proof of statistical significance will be more probable.

Diarrheal diseases of calves are one of the most serious risks of rearing calves and cause economic losses. For this reason, the objective of this work was to assess the influence of means of support in operating conditions for the incidence of diarrheal disease in calves in the early post-weaning stages. A company was chosen for this work in which both the company employees and an external veterinarian were willing to collaborate and provide not only information about the breed in question, but also biological material. This company was JINOS - AGRO Veselí nad Lužnicí. The calves were observed in the period of April - June 2009. The calves were housed in separate boxes the second day after birth until the average age of 56 days. After storage, they were divided into 5 groups: 4 based on the chosen means of support, and a single control group. Faeces samples were collected from the calves and subsequently evaluated. The calves to whom were administered means of support were then evaluated to assess the effect thereof on the incidence of diarrhea, the duration of diarrhea, the method of treatment, and the duration of treatment. The results were summarized and analyzed using a statistical program (STATISTICA 7.0.). There was no statistically significant difference found between the individual groups and the experimental group. An evident and statistically significant difference was found only in the case of a difference between the drugs of the 2 experimental groups, specifically between Lactovita and Homeopatika. Based on this observation, it can be stated that there was no evidence supporting the effectiveness of administered means of support for the incidence of diarrheal disease in calves in the early post-weaning stages.