Abstract
This article shows the results of scientific research on raising the Holstein-Friesian heifers from birth to 12 months of age, with the introduction to their feeding regimen of "Neomilk" whole milk replacer, as well as the "Gavryusha" commercial prestarter and starter during the preweaning period and the extruded feed called "NFT KATU," produced by S. Seifullin Kazakh Agrotechnical Research University during the preweaning and postweaning periods. Three groups of calves were formed using a pair-matching method for the main research. Studies on body weight dynamics were conducted at the Aina Dairy Farm LLP with the calculation of daily average, relative, and absolute weight gains. At three months of age, the body weight of heifers in the second test group exceeded that of the control and the first test group by 7.8 kg (8.8%) and 6.8 kg (7.7%), respectively. At six months of age, the difference increased to 34.4 kg (30.7%) and 23.4 kg (19.2%). By 12 months of age, the gap widened to 106 kg (47.3%) and 77 kg (33.4%). Outline characteristics were also analyzed by taking measurements and calculating body condition indexes of the heifers. An analysis of the feeds used in animal feeding was conducted. The chemical composition analysis of the feeds revealed that the extruded feed had the highest protein content reaching 12.9%, which was 2.8% and 1.5% more than bran and "Gavryusha" prestarter, respectively.