Milk yield and chemical composition of sheep milk in Srednostaroplaninska and Tetevenska breeds

The study was conducted from April to July on pastures located at different altitudes and of different sward composition during the milking period of Srednostaroplaninska and Tetevenska sheep. Morning bulk milk was sampled for analysis monthly between April and end of July. The purpose of the study was to establish the milk yield and to investigate the chemical composition of sheep milk obtained from Srednostaroplaninska and Tetevenska breeds reared on pastures at a different altitude and with different sward composition. The Tetevenska breed had a higher daily milk yield and exhibited a high percentage of casein in milk, while the milk from Srednostaroplaninska sheep had a higher content of macro elements - calcium, potassium, magnesium and some trace elements (iron and manganese). The milk fat content, including the percentages of saturated and unsaturated fatty acids in milk obtained from studied breeds, was similar. There was a tendency towards higher percentage of polyunsaturated and long-chain fatty acids in the milk of Srednostaroplaninska sheep, reared on mat grass pastures. Milk casein content was higher in the milk of Tetevenska sheep, as well as the content of non-essential amino acids as compared to Srednostaroplaninska sheep.