Monitoring of blood metabolic profile and milk quality of ewes during lactation in organic farming

The aim of this research was to monitor the metabolic profile of blood and the quality of ewes’ milk during lactation in organic farming. Biological investigations were carried out on 32 clinically healthy Merinolandschaf ewes during the 3th lactation on the 20th, 60th and 100th day of lactation. Ewes’ milk was analyzed for the non fat dry matter, milk fat, protein, lactose, urea, the somatic cells count (SCC) and te total viable cell number (CFU), as well as for the concentration of fatty acids, atherogenic (AI), thrombogenic (TI) and Δ9-desaturase activity index. Concentrations of minerals (Ca-calcium, P-phosphorus-inorganic, Mg-magnesium, and Fe-iron), biochemical parameters (urea, glucose, cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, total protein, albumin, globulin, NEFA-non-esterified fatty acids, BHBA-beta-hydroxybutyrate) and enzyme activity (ALT-alanine aminotransferase, AST-aspartate aminotransferase, ALP-alkaline phosphatase, CK-creatine kinase and GGT-γ-glutamyl transferase) were analyzed in blood serum. Chemical composition of milk differed among different stages of lactation, which was marked by the increased content of milk fat, the decreased urea concentration, as well as by numeorus changes of fatty acid concentration observed along with lactation progression. Number of SCC and CFU in milk increased during lactation. AT and TI were appropriate in all stages of lactation, which resulted in satisfactory quality of ewes’ milk from organic farming. Determined concentrations of certain biochemical parameters (NEFA, triglycerides, VLDL-cholesterol, Ca and Fe) in blood of ewes originating from organic farming indicated lower deficit of energy during the 20th day of lactation, as well as a lack of Ca and Fe concentrations in blood, which most likely occurred due to higher loss through milk. Accordingly, the blood metabolic profile can be considered as an indicator for feeding and health status of ewes during lactation in organic farming.