Physical and chemical composition of goat milk during smallholder production in the conditions of the natural and agricultural zone of the Steppe of Ukraine

Abstract

The purpose of the work was to determine the performance of goat milk in smallholder production in optimal climatic conditions of the Donetsk-Dnipro region of the Left Bank province of the natural-agricultural zone of the Steppe of Ukraine. According to the definition of the temperature - humidity index, the climate acceptable for goats is observed in April. Mean values and standard deviations of physico-chemical parameters of milk were found in local goats at lactation: fat 4.32 ± 1.25%, protein 3.22 ± 0.24%, lactose 4.78 ± 0.37%, fat ratio / protein 1.35 ± 0.42, milk solids-not-fat 8.67 ± 0.65%, density 29 ± 300A, freezing point -0.567 ± -0.0390C, electrical conductivity 4.49 ± 0.47 mS / cm, pH 6, 73 ± 0.09, acidity 15.7 ± 1.90T.  At the peak of the lactation curves, local goats showed a decrease in protein and lactose content, instead of an increase in fat. The expressiveness of such a disproportion was manifested in the dynamics of the values of the ratio of fat / protein, milk solids-not-fat and milk density.  Therefore, during the first 2-3 months of lactation, when milk is actually the only source of nutrients for plastic and energy metabolism for goatlings, the concentration of lactose and protein is high. At the age of 3–4 months goatlings have to satisfy most of their needs due to their own search for feed, which is why the composition of goat's milk reflects this process of formation of the young's animal digestive system. The decrease in milk depression (higher freezing point) during the lactation peak probably reflects a change in the total concentration of osmotically active substances, especially lactose, at this time. The gradual increase in the electrical conductivity of milk throughout the lactation is caused by the accumulation of electrolytes coming from the blood of animals. In fact, the stable pH and acidity of milk confirm the high resistance of local animals to breast diseases, especially subclinical mastitis caused by technological stress on animals under conditions of intensive production technology. The presence of 87 % of the population of goats both in Dnipropetrovsk region and in Ukraine as a whole means that it will remain important for a long time to ensure the proper level of servicing of small cattle in individual peasant farms rather than in specialized enterprises.