Features of lactation and quality of milk of different breeds of goats

Abstract

Milk productivity during the lactation period (305 days) and evaluation of milk according to different quality indicators in periods of the year were studied. The experiments were carried out on 3 groups of goats of Zaanen, Alpine, and Anglo-Nubian breeds at 3–4 years old. Milk productivity was evaluated from the 1st to the 11th month of lactation, and milk quality indicators (fat, protein, SOMO, density) were analyzed using the Lactan 1-4 milk analyzer. It was established that the most incredible intensity of lactation in goats occurs during the 4–5th month after farrowing; the exceptional dynamics of the lactation curve is that it increases from the 1st to the 4th month and decreases from the 5th to the 10th. An interbreeding difference in milk yield was established (Р < 0.001, Р < 0.05) in the 4th, 5th, and 7th months of lactation, where the Anglo-Nubian, Alpine, and Zaanen breeds were arranged in the order of decreasing milk yield. The total lactation rate was maximum in Zaanen animals, and in Anglo-Nubian and Alpine goats, it was lower by 16.4 % (Р < 0.001) and 5 % (Р < 0.001), respectively. It was found that the average daily fertility of goats was in Zaanen animals, and the minimum and maximum in Anglo-Nubian and Alpine breeds about the season of the year, correspondingly spring – 15.9 %, 6.5 %; summer – 16.04 %, 3.74 %; autumn – 23.2 %, 8 %. The study of the physicochemical parameters of goat milk of various species revealed that, according to qualitative parameters, in the spring, summer, and autumn periods, there is an interspecies difference in the content of protein and fat, with the highest content in Anglo-Nubian animals, respectively by 5% (Р < 0.001), 38.6 % (P < 0.01), 36.1 % (P < 0.01). According to indicators of consistency and smell of milk, the three breeds of goats did not have a probable difference. The following discrepancies were established regarding taste qualities: a sweet taste in Anglo-Nubian animals, a rich one in Alpine animals, and no extraneous aftertaste in Zaanen animals. A light cream color is noted in the Anglo-Nubian circles, and a color variation from white to light cream is present in the Alpine and Zaanen peoples.