Characterization of Several Milk Proteins in Domestic Balkan Donkey Breed during Lactation, Using Lab-on- -a-chip Capillary Electrophoresis

Domestic Balkan donkey (Equus asinus asinus) is a native donkey breed, primarily found in the northern and eastern regions of Serbia. The objective of the study was to analyze proteins of Domestic Balkan donkey milk during the lactation period (from the 45 to the 280 day) by applying lab-on-a-chip electrophoresis. The chip-based separations were performed on the Agilent 2100 Bioanalyzer in combination with the Protein 80 Plus lab chip kit. The protein content of domestic Balkan donkey milk during the lactation period of 280 days ranged from 1.40 to 1.92% and the content of αs1-casein, αs2-casein, β-casein, α-, β-lactoglobulin, lysozyme, lactoferrin and serum albumin was relatively quantified. Lysozyme (1040-2970 mg/L), α-lactalbumin 12 kDa (1990-2730 mg/L) and α-lactalbumin 17.7 kDa (2240-3090 mg/L) were found to be the proteins with the highest relative concentrations.