The current methods of preventing calcium deficiency during the periparturient period are based primarily on a diet low  in calcium and acidifying the rumen content before parturition, as well as on oral administration of liquid preparations or boluses. The available literature does not provide information on whether these forms of prevention are effective only immediately after the parturition, or whether they also affect an organism throughout the initial lactation period. The aim of the study was to examine the effects of three methods for the prevention of postpartum hypocalcaemia on selected indicators of mineral and energy metabolism, as well as on functional parameters of the parenchymal organs during the two week period following parturition in dairy cows diagnosed with low calcium concentrations before parturition, induced by a lower dietary mineral content. The study was conducted in 60 HF cows, aged 3-6 years old, fed TMR. The animals were divided into three groups: the first group received only a mineral preparation contained in the feed, adjusted to the physiological stage and milk production level; the second group received three additional doses (directly before the parturition, then 24 hours and 48 hours after the delivery) of an oral fluid preparation containing 62.5 g of Ca; while the third group received an intraruminal bolus containing 43 g of pure calcium (immediately after parturition). This research showed that physiological hypocalcaemia occurred at the beginning of lactation in the groups which had received additional calcium preparations (groups II and III), whereas in group I blood collection one week and two weeks after the parturition demonstrated subclinical hypocalcaemia. A statistically significant increase in magnesium and a decrease in phosphorus concentrations were also observed in the latter group, as well as an excessive GGTP activity and high bilirubin concentrations. Using only one complex mineral supplement in high yielding milk cows after parturition does not ensure the expected prophylactic effects, especially in the long term.   .

21.1.2016