Improvement of elements of cultivation of milk heifers on farms and complexes for milk production

Abstract

The article examines the problem of forming groups of heifers in the dairy period in order to obtain cows with high milk productivity, as increasing milk production is an important and complex problem of agricultural science and practice.
 The results of a study on improving the breeding of heifers of the Ukrainian black-and-white dairy breed in the conditions of the State Enterprise "Kutuzivka" of Kharkiv region are presented.Scientific and economic research was focused on substantiating the effectiveness of the influence of different numbers of heifers in the technological group on their growth and development in the milk period of ontogenesis. It was found that the actual difference in feed consumption in each series of experiments between animals in each group of 5-10-15-20 heads and a den area of 1.8 m2-2.2 m2 on deep straw litter was not. And when comparing technological groups of 5-20, 10-20, 15-20 heads, differences were revealed.
 In the production conditions of the dairy complex of SE Kutuzivka of Kharkiv region, the experiment was conducted in the spring-summer period. The experimental groups were formed as follows: for research, four technological groups of heifers with a population of 5, 10, 15 and 20 heads in each were selected, which were kept on a deep straw litter with a den area of one head 1.8–2.0 – 2.2 m2.
 It is experimentally proven that the use of growing heifers from 10 days of age to 6 months. loose on a deep straw litter in group sections of 5, 10 and 15 heads compared to the counterparts of 20 heads, contributed to an increase in live weight gain on average during the experiment by 20.5-22.5 % (P <0.05) . It is established that the technology of cultivation in the spring-summer period in the premises of light type contributes to the increase of the average daily increase from 27.2% to 30.3 % (P <0.05).
 Under these conditions of growing heifers in the technological groups of 5, 10 and 15 heads in comparison with the analogues of the group of 20 heads there was a reduction in feed consumption per 1 kg of live weight gain by 20.4 –26.5 %.
 Analysis of the results on the formation of technological groups of heifers in the production conditions of the dairy complex showed that the maintenance of heifers in the technological group of 15 heads and an area of 1.8 m2 per head is the best. Since the results of the comparative analysis of the complex efficiency of each of the options N(Ck)compared to the idealized, showed a significant advantage of this option, for which the target function according to the considered criteria was lower and was 0.0894. Other options were 1.0381 – 3.5839 times worse.

An Investigation on the Effects of Partial Replacement of Rapeseed Cake in Ayrshire Dairy Heifers’ Diets with By-Product Source of Animal Protein on Body Weight Dynamics, Nutrient Balancing, and Blood Biochemical Markers

“…These results are primarily due to the fact that up to 6 months the calves' rumen does not fully function and calves mainly produce digestion in the abomasum and the small part of the gastrointestinal tract. So, some authors indicated that for the development of a fully-fledged highly productive cow from a calf, it is necessary to pay attention, first of all, to the amount of protein in the diet and its amino acid composition [47,51,52].…”

“…The rearing of heifers is a key issue on dairy farms, because these animals ensure the maintenance and renewal of the herd [47,59]. Thus, heifer rearing is a necessary process on which the high productivity of cows programmed at the beginning of heifer rearing depends [51,52]. Thus, the assessment of blood metabolic profiles is necessary to monitor the health, reproduction and physiological conditions of the animal, which can prevent metabolic disorders in animals [60,61].…”