The aim of this study was to evaluate the influence of environmental housing conditions on the milk yield of dairy cows. Measurements were taken in the summer period from June to September 2020 and in the winter period during January 2021 on a large-capacity farm of Holstein Friesian cattle. Cows were housed in free stall barn with the lying boxes and selected during the second or third lactations, in the summer period from the 51st day to the 135th day and in the winter period from the 64th day to the 120th day of lactation. The average temperature in the housing was 23 °C in summer, and 7.05 °C in winter. The average THI (thermal humidity index) value in summer was 70.43, but during the day the THI values sometimes reached 75. The dairy cows were therefore exposed to heat stress during summer. Increasing THI and temperature values negatively affected the milk yield, as there was a negative correlation between both THI and milk yield (r = -0.641; p <0.01) and temperature and milk yield (r = -0.637; p <0.01). Milk production in winter was at 58.77 kg per day and in summer at 49.55 kg per day. In the summer, the milk had a significantly lower content of fat (p <0.05), proteins (p <0.001), lactose (p <0.001), minerals (p <0.001) and conversely, a higher number of somatic cells (p <0.01). These results show that worse environmental conditions during the summer negatively affected the level of milk yield and the composition of the cows’ milk.

The aim of the experiment was to assess the pig meat quality in relation to preslaughter conditions and import country. In the experiment, the meat quality of 1980 pigs was evaluated. The animals were divided into three groups according to country of import (Slovakia, Hungary and Netherlands). The following pre-slaughter indicators were evaluated: duration of transport, duration of housing, temperature during housing and transport. The meat quality was judged on the basis of the pH 1 value measured 45 minutes after the slaughter in the musculus longissimus dorsi-pH 1 MLD and in the musculus semimembranosus-pH 1 MSM. The highest frequency of PSE (pale, soft, exudative) meat in the MLD was in the group of pigs imported from Slovakia (24.13 %). These pigs had also statistically significant (P<0.01) the lowest average pH 1 MLD (6.05) in comparison with other imports. The incidence of PSE meat in the MSM was in all evaluated groups above 10 %. Group of pigs from Slovakia had the lowest value of pH 1 MSM (6.23) in comparison with other groups of pigs (P<0.01). Even though the average length of housing in a slaughterhouse was from 11.26 to 15.43 hours high incidence of PSE meat was recorded. However group of pigs with the longest rest period (15.43 hours-Netherlands) had significantly higher pH 1 MLD and pH 1 MSM compared to other imports (P<0.01). From these results can be concluded that the incidence of PSE meat in evaluated groups is relatively high. Prolonging rest period and lower temperatures had positively influence on the incidence of PSE meat and pH value.

The aim of this study was to evaluate the effect of induced training on the horses’ metabolism during an experiment lasting nine weeks where we continually scaled up the load on the horses by three defined stages. Blood was obtained from eighteen horses – two stallions, eight mares and eight geldings. In the experiment, we focused on the biochemical analysis of the blood plasma on multiple mineral profile indicators – Ca, P, Mg, K, Cl and Na, and some other variables (energy, nitrogen, AST, ALT, glucose, urea, creatinine kinase, total proteins). The result showed significant changes between the groups in most indicators. A significant increase in the potassium, phosphorus and calcium and a decrease in the concentrations of magnesium over the course of the experiment were found. For the other indicators, a significant increase in the activities of the AST and ALT out of the other indicators and the fluctuating values in the total proteins were noticed. Summarised, significant changes of multiple indicators were observed in different stages of the experiment. These changes had no visible effect on the horses’ organisms throughout entire duration of the experiment and were most probably caused by the muscular work and possible muscular damage during training.

In the experiment we judged the influence of genetically modified plants on the fattening-, carcass-, and pig quality parameters. We have recorded better fattening parameters in the group fed with the GM crops. We recorded statistically provable differences in the number of the test fattening days (30-100 kg), in the lifelong average daily gains, in the test fodder consumption (30-100 kg). We have recorded better carcass indicators in the group fed without the GM plants, which was statistically confirmed in the valuable meaty parts as well as thigh portions. There were no statistically provable differences found out in the meat quality indicators between the groups.