Studies on the use of different doses of propylene glycol in dairy cows during the periparturient period

The study was performed on 24 high-yield dairy cows divided into three groups (n=8) by the method of analogy: control group I. which did not receive propylene glycol, group II receiving propylene glycol in quantities of 250 ml/day/per head, and group III receiving propylene glycol in quantities of 500 ml/day/per head. The mixture was administered to the cows beginning from 2 weeks before parturition to day 21 of lactation. Selected parameters of carbohydrate and lipid metabolism, total bilirubin concentration as well as AST, ALT and GGT activity were marked in the blood serum, whereas the acid base equilibrium parameters were marked in the entire blood. All the tests were undertaken 2 weeks before parturition as well as 7, 21 and 42 days after parturition. A growth of FFA levels in all the groups of cows was confirmed at the beginning of lactation. Applying propylene glycol limited the growth of P-hydroxybutyrate acid concentration as well as decreasing the glucose concentration in the blood serum of the cows in the first period after parturition, thus reducing the risk of ketosis. Long-term administration of various doses of the preparation had a similar impact on the carbohydrate-lipid metabolism of the dairy cows and there was no negative effect on liver function.