G. Bonev, R. Slavov, S. Georgieva, P. Badarova, S. Omar
Abstract. The objective of this study was to investigate blood serum levels of Ca, P and protein before hormonal treatment for estrus synchronization in ewes. In the experiment, the average level of calcium in the blood serum of sheep in the performed researches was from 1,905 to 2,28 mmol/l of the serum. Those are the values which can be marked as ordinary and within normal range. The dairy sheep in lactation (Group 2) had the lowest level of calcium (1,905mmol/l) which is below the normal range. In that period, the level of calcium in the blood serum declined to the lower limit of the normal values, under which the state of deficit could be indicated. These adult ewes had the lowest fertility rate (54%). The average level of phosphorus 1,26 mmol/l of the serum in Group 2 was below the normal level of this element in the blood of the sheep (1,4-2,5mmol/l). In Group 1 and 3, the level of phosphorus was 1,57 and 1,86 of the serum, which are the normal values. In the blood serum of the dairy sheep, these values declined to 1,26 mmol which marked the deficit value. Serum total protein showed a significant difference between the experimental groups. The lowest rate (57,3 g/l) was in the ewe lamb group, which is below the normal range. Deficiency of serum protein resuls in decreased reproduction parameters (fertility 40%, fecundity after synchronization 54,28%), and compromised health and it affects reproductive performance.