Blood metabolic profile and complete blood count of sheep during late pregnancy and lactation

The research was performed on 30 adult clinically healthy Lika Pramenka sheep, aiming to determine the influence of late pregnancy and lactation on blood metabolic profile and complete blood count. Sheep were, on average, 5 years old, in the fourth lactation. The sheep were fed meadow hay at an amount of 1.8 $\mathrm{kg}{d}^{-1}$ and oat at an amount of 800 $g{d}^{-1}$ . Blood was sampled during the late-pregnancy stage of the sheep (on the 20th day before lambing) and during the lactation period on the 40th, 70th and 100th days. Complete blood counts determined in this research were the blood cell counts; hemoglobin (HGB), hematocrit (HCT) and erythrocyte constants; and differential blood count. Biochemical analyses in sheep blood serum determined concentrations of minerals, metabolites and enzyme activities. This research proved that the late pregnancy and lactation had a significant influence on the indicators of the sheep's blood metabolic profile and complete blood count. Significant changes in complete blood count were particularly expressed in late-pregnancy and lactating sheep in the first measurements, especially in terms of values of RBCs (red blood cells), HGB, HCT, PLTs (platelets), lymphocytes and neutrophils; indicators of energy (NEFAs or non-esterified fatty acids, glucose and triglycerides), protein (TP or total protein, ALB or albumin, urea) and mineral status (Ca, P-inorganic); and liver status (changes in most liver enzymes). Moreover, the quality of feed (protein and mineral content) plays an important role in the determination of the blood metabolic profile and complete blood count of sheep during late pregnancy and lactation. Therefore, this research suggests that studies should include late pregnancy and lactation and feed quality in the determination of the metabolic profile and complete blood count of sheep's blood in order to obtain the best possible information on the herd.