The content of total serum calcium averaged 2.16±0.023 mmol/l, which is 4 % less than the minimum norm (2.25 mmol/l) in dry cows at the beginning of the experiment. Low content of calcium in the blood serum of cows is evidence of hypocalcaemia.

Total calcium content in the experimental cows increased slightly and its average content was 2.23±0.09 mmol/l, which shows only a trend (p<0.5) to its growth after the drug Mehavit.

The concentration of inorganic phosphorus in dry cows had the opposite trend: if at the beginning of the content was 1.88±0.16 mmol/l, at the end – 12.8 % less (1.64±0.15 mmol/l). In total the content of inorganic phosphorus in experimental animals was (1.45–2.2 mg/l).

The best effect of the drug Mehavit gave on vitamin A metabolism in animals. At the beginning of the experiment vitamin A in experimental animals was 29.5±1.25 mg/100 ml, slightly above the lower limit of normal (25 mg/100 ml). For cows repeated blood tests of vitamin A they increased to 37.6–46.2 mg/100 ml (41.0±2.26 mg/100 ml), 39 % more than the previous rate (p <0.01).

The use of dry cows vitamin A in doses of 25–30 ml (375–450 000 IU once every 7 days) contributes to vitamin A in the blood serum.

Experimental blood parameters had a similar trend. In particular, total calcium content in early experiment was within the minimum standards (2.25 mmol/l), and the average value was 2.28±0.04 in dairy cows. The level of total serum calcium, since the mean value (2.37±0.065 mmol/l) was only 3.94 % higher on the previous rate (p<0.1) after the drug was increasing

The content of inorganic phosphorus in dairy cows after the drug Mehavit tended to decrease (to 11.05 %, p<0.1) and the average of the group (1.69±0.12 mmol/l) does not go beyond the norm.

Unlike macroelements, exchange vitamin D in dairy cows had positive changes. In particular, if at the beginning of the experiment, 80 % of cows vitamin A in serum was lower minimum rate (25 mg/100 ml) and averaged 21.9±1.75 mg/100 ml, the Mehavit helped to increase retinol content to 30.8±1.25 mg/100 ml (+ 40.6 %; p<0.01). All cows after the drug concentration of vitamin A was within normal limits.

Total calcium in early experiment was low and averaged 2.15±0.05 mmol/l, well below the minimum rate – 2.4–2.5 mmol/l in calf serum. After the drug content Mehavit macroelements by 11.2 % and averaged 2.39±0.04 mmol/l (p<0.01).

The content of inorganic phosphorus use in calves after Mehavitu did not change (p<0.5): the use of the drug it was 2.5±0.068 mmol/l, and after the experiment – 2.38±0.08 mmol/l.

As in cows in early experiment of vitamin A in all calves were in the normal range (16.7–21.4 mg/100 ml) and averaged 19.3±0.61 mg/100 ml. Four time of Mehavit administration boosted retinol content in the calves 24.9 % (p<0.01).

Thus, the drug Mehavit helped optimization of total calcium and inorganic phosphorus positively affect the concentration of vitamin A in the blood serum of young cattle.

In 60 % of horses before introduction Mehavit average content of total calcium was within minimum standards was 2.6±0.09 mmol/l, the rest – slightly less. At the end of the experiment, all the horses increased calcium levels and average (2.85±0.03 mmol/l) was significantly (p<0.05) higher (9.6 %) than before the introduction of the drug. The content of inorganic phosphorus to the drug was significantly less than normal (1.1±0.04 mmol/l) after it reduced to 0.91±0.02 mmol/l (p<0.01).

The content of serum retinol in 40 % of horses was slightly lower minimum rate (20 mg/100 ml, according to other sources – 15 mg/100 ml). On average, its level was 21.0±0.98 mg/100 ml. After the experiment is set to grow retinol (39.5 %) to 29.3±1.80 mg/100 ml (p<0,01).

In all lactating sows content of total calcium was lower standards (2.5–3.25 mmol/l) and was 2.1±0.04 mmol/l. The level of inorganic phosphorus, unlike calcium was in the normal range (2.08–2.16 mmol/l). After the usage Mehavit drug total calcium content in sows increased on average by 19.0 % and amounted to 2.5±0.09 mmol/l. In contrast, total calcium levels remained stable inorganic phosphorus (2.13±0.05 mmol/l and 2.15±0.063 mmol/l) during the observation period.

In pregnant sows content of total calcium was lower standards (1.83–2.15 mmol/l) was 1.97±0.05 mmol/l, indicating insufficient provision of calcium and vitamin D. The use of Mehavit was very effective because the content of total calcium increased by 39.6 % (2.75±0.11 mmol/l, p<0.001) in all sows were within normal limits.

The content of inorganic phosphorus in pregnant sows before usage of Mehavit was in the normal range (2.35±0.09 mmol/l) and even significantly exceeded it in some animals. The introduction of the drug stimulated the absorption of macronutrients and its level in serum increased to 2.66±0.04 mmol/l (13.2 %; p<0.05).

In most pregnant and lactating sows vitamin A was within the minimum norm (20–50 mg/100 ml) and averaged 21.3±2.00 mg/100 ml and 22.4±2.00 mg/100 ml. Introduction of the Mehavit boosted the content of retinol in pregnant sows to 30.5±2.25 mg/100 ml (+ 43.2 %; p<0.05), lactating – 36.6±3.50 mg/100 ml (+ 63.4 %; p<0.01).

Thus, the drug Mehavit in experiments on pigs showed a positive effect on the calcium content in serum (growth in pregnant sows accounted for 39.6 % of lactating – 19.0 %; p<0.001 and p<0.01), inorganic phosphorus lactating sows by 13.2 % (p<0.05). These changes are due to the positive influence of a metabolite of vitamin D₃ – 1.25(OH)₂D₃ synthesis calcium binding protein in enterocytes, the absorption of calcium and phosphorus in the intestines and its reabsorption in kidneys [5, 14, 15, 18, 20, 25, 26].

The most revealing were the changes in the concentration of vitamin A: its number increased by 43.2 % and 63.4 % in pregnant and lactating sows, respectively (p<0.05 and p<0.01).

Key words: Mehavit, vitamin A, macroelements, total calcium, inorganic phosphorus, metabolism.