Milk productivity of cows of different ages under the conditions of the dairy complex «Ryzhovo»

Abstract

When production of milk in industrial volumes it is necessary to monitor all processes aff ecting its quantity and quality: animal feeding, breeding, mode and method of milking, herd reproduction, labour organization in the dairy complex, creating favorable conditions for cows that correspond to physiological characteristics. The dairy industry continues to impose higher and higher demands on milk, so in addition to improving the milk productivity of cows, we must not forget about the quality of the product. The issues of milk yield of cows, fat and protein, yield of milk fat and protein, somatic cells in milk of cows of Black-and-White breed for a number of lactations in terms of the dairy complex “Ryzhovo” have been considered in the article. It has been noted be researches that in the 1st and 2nd lactations milk yield of animals was 10 621 and 10 553 kg, respectively. The highest productivity of the cows has reached in the 3rd and 4th lactations 11 365 and 11 655 kg, respectively, after which, in the 5th lactation there was a decrease in milk yield to 10 592 kg. When considering fat content for diff erent lactations, positive dynamics up to the 4th lactation inclusive has been revealed. Thus, the fat content in milk for the 1st lactation was 3,61 %, for 2nd – 3,68 %, for 3rd – 3,93 % and 4th – 4,00 %. In the 5th lactation fat content decreased to 3,78 %. It has been found when calculating the yield of milk fat in experimental cows for lactation that up to the 4th lactation inclusive the indicator increases: for the 1st lactation received 383 kg of milk fat, 2nd – 388 kg, 3rd – 447 kg, 4th – 466 kg, and for the 5th lactation, the decrease in the index to 400 kg. At the same time the yield of milk fat for the 5th lactation exceeds the 1st and 2nd. The protein content in the milk of cows of diff erent ages during the fi rst four lactations increases from 3,18 to 3,43 %. Then, in the 5th lactation there is the decrease in protein content to 3,35 %, however, this fi gure is second only to the highest the 4th lactation. It has been established that before the 3rd lactation the number of somatic cells in milk increases, then in the 4th lactation this indicator decreases (151,25 thousand/cm3 ) and in the 5th lactation reaches a maximum (242,27 thousand/cm3).