GROWTH AND DEVELOPMENT OF HEIFERS OF THE CREATED SIMМENTAL MEAT BREED
Authors: Dedova L. O. , Bashchenko M. I. , Vdovychenko Yu. V. 
Published: July 2021

Introduction. When creating the Simmental beef breed of cattle during many years carried out researches to study the effectiveness of the use of meat Simmentals of foreign selection in crossbreeding with cows of Simmental breed of domestic selection. Were created the herds of the desirable type by breeding "in themselves" animals, that meet the requirements of the target standard, formed a genealogical structure.
Now carry out the work with related groups of cattle of the created Simmental meat breed, which are the basis for the creation of further lines, but the growth and development of animals of different related groups have not been sufficiently studied. Therefore, the study problems of growth and development of repair heifers of different related groups has not only theoretical, but also practical importance.
The purpose of our researches was to study the dynamics of linear growth and weight development of heifers of different related groups of the created Simmental meat breed.
Research materials and methods. The researches was carried out on heifers of different related groups of the created Simmental meat breed in PJSC "Dniprovske" of Boryspil district of Kyiv region. To analyze the growth and development of heifers were formed groups of animals depending on their belongings to related groups of 15 heads in each: I Group – Metz 5290; II – Achilles 369; III – Abricot 58311; IV – Huxla 19223; V – Hercules 8942 and VI – Signal 120.
Research results. It was determined, that heifers of the II group, which belong to the related group of Achilles 369, by live weight at all ages of periods surpass to peers. Thus, at 18 months of age the advantage of heifers of the II group by live weight in comparison with to peers of the I, III, IV, V and VI groups was 4.1; 3.0; 5.0; 14.1 and 11.4 kg.
In heifers of related groups Hercules 8942 and Signal 120, the coefficients of variability of live weight at birth in which were the lowest, and in the following age periods they little changed, therefore at 18 months of age in these heifers they were the highest, comparison with analogues, and was to 8.4 and 9.2%, respectively.
When studying the exterior of heifers of different related groups it was determined, that newborn heifers of the I group, which belong to the related group of Metz 5290, surpass their peers in height indicators. Their the height at the withers and the height at the sacrum were 74.0 and 79.1 cm, which is 0.6; 1.3; 2.1; 3.2 and 2.6 cm and is 0.3; 1.2; 2.9; 3.6 and 3.2 cm more than in analogues of the II, III, IV, V and VI groups, respectively.
The best indicators of latitudinal measurements had the heifers of the III group, which belong to the related group Abricot 58311. In heifers of this group the width of the chest was 17.6 cm, width in the hip joints – 21.8 cm, width in the hips – 18.1 cm, and width in the ischial tubercles – 12.6 cm.
The depth of the chest and the girth of the chest behind the shoulder blades were the highest in heifers of the I group, which belong to the related group of Metz 5290. They were 32.2 and 79.6 cm, respectively.
When analyzing the measurements of heifers at 18 months of age, it was determined, that the height indicators had advantage by heifers of the II group, which belong to the related group of Achilles 369. Their, the height at the withers and height at the sacrum were 124.5 and 129.8 cm, which is 0.3; 1.3; 2.5; 5.3 and 4.2 cm and is 0.9; 2.2; 4.1; 6.6 and 5.9 cm more than in analogues of the I, III, IV, V and VI groups, respectively.
The best indicators of latitudinal measurements had the heifers of the III group, which belong to the related group of Abricot 58311, since they had increases of measurements width of the chest, width in the hip joints, width in the hips and width in the ischial tubercles for the period from birth to 18 months of age the highest comparison with peers.
Such indicators as depth of the chest and the girth of the chest behind the shoulder blades were highest in heifers of the II group, which belong to the related group of Achilles 369. Their increases of measurements depth of the chest and the girth of the chest behind the shoulder blades for the period from birth to 18 months of age also were highest comparison with peers and were 35.5 and 94.2 cm, respectively.
Conclusions. It was determined, that the animals of the related group of Achilles 369 at all ages of periods had a large live weight in comparison with their analogues. The lowest coefficient of variability of live weight at 18 months of age was in heifers of the related group Abrikot 58311 and amounted to 6.5%. Heifers of the related group of Achilles 369 had the highest indicators of the following measurements: height at the withers (124.5 cm), height at the sacrum (129.8 cm), depth of the chest (67.4 cm), girth of chest behind the shoulder blades (173.1 cm) and oblique length of body (146.4 cm). The highest latitudinal measurements were observed in the heifers of the related group Abrikot 58311. Thus, the width of the chest was 49.9 cm, the width in the hip joints was 42.2 cm, the width in the hips was 43.3 cm, and the width in the ischial tubercles was 29.2 cm. Heifers of the related group Metz 5290 had the highest half-girth croup (110.2 cm) and girth of metacarpus (18.4 cm). In general, heifers of all groups showed good energy of growth and a typical for beef cattle exterior.