The study included a total of 127 sheep milk samples from two different areas (Livno and Travnik) in summer feeding period (July, August and September). Fatty acids in milk were determined by gas chromatography (GC). The animals were marked with the appropriate number of ear tags on the basis of which we always took samples from the same animals through different periods. Fatty acids in milk were determined by gas chromatography and the following fatty acids composition: butyric acid, caproic acid, caprylic acid, capric acid, stearic acid, oleic acid, linoleic acid, arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, rumenic acid. The fatty acid content of sheep's milk in this study showed a tendency of variation, both within and between sampling areas, and characterized by its relatively high content of saturated fatty acid (SFA) during the period of harvest.

Scientific knowledge about the predispositions of Bosnian native breeds of sheep (Dubska) for the production of milk and milk products until recently were quite sparse and very scarce. Therefore, the aim of this study was to investigate the biochemical indicators and serum minerals, for monitoring the nutritional status. Until now subject research did not include testing of the effect of biochemical parameters and hormonal status of the blood of sheep on the quality of milk and milk products. Persistence of this connection is justified by the fact that most of the ingredients of milk just derived from the blood. The main objective of this research was to explore metabolic parameters of sheep’s blood, and their relative importance on the quality and quantity of milk components. The study included a total of 127 sheep blood samples from two different areas (Livno and Travnik) in summer feeding period (July, August and September). The animals were marked with the appropriate number of ear tags on the basis of which we always took samples from the same animals through different periods. In sheep blood serum, the concentration of biochemical parameters (glucose, cholesterol, triglycerides, total protein, albumin, urea, AST, ALT, AP, GGT, LDH, calcium, phosphorus and magnesium) and metabolic hormones (triiodothyronine, thyroxine, and insulin cortisol), and samples of milk: milk parameters (milk fat, lactose and protein) as well as fatty acid composition of the milk. The concentrations of blood biochemical parameters were determined by spectrophotometry with automated analysis with ready-made package of slides. Concentrations of metabolic hormones (T3, T4, cortisol and insulin) in the serum were determined by ELISA method. The percentages of fat, protein and lactose in milk were determined by infrared spectrophotometry. Fatty acids in milk were determined by gas chromatography (GC). Our research showed hypoglicemia, mild hypoproteinemia and hypoalbuminemia probably due to nutritional deificiencies during lactation period. Negative energy balance could be responsabile for changes found in the cholesterol concentration as well as in the activity of ALT, AST, GGT, LDH. Significant differences in milk fat and milk protein, as well as fatty acids composition were determined between localities and season sampling. In general, our results showed varriation of blood biochemistry and milk quality. Due to differencies in climate, botanical differences of soil and pasture these variations are considered to be acceptable. Statistical analysis was performed using the software package SPSS 15.00 (for biochemical paramters and parameters of milk) and 21.00 (for metabolic hormones and fatty acid composition of the milk).

The aim of this study was to investigate liver function in dairy sheep during summer and consequences made by heat stress. The experiment was performed on 117 Pramenka sheep at two different locations (Travnik and Livno) during summer grazing period (July, August and September). Levels of serum enzymes were determined for alanine aminotransferase (ALT), aspartate aminotransferase (AST)), gamma-glutamyl transferase (GGT), alkaline phosphatase (AP) and lactate dehydrogenase (LDH). Enzyme activities resulted in significant (P<0.05) variation except GCT and a moderate increase followed by dcrease in activity, which is likely to be correlated with the energy balance of animals. Values of serum profile above reference range may indicate intense metabolic processesasaliver response toa negative energy balance. The results of this research couldbeused for the determination ofhealth status.