This experiment was conducted to study the effect of a prolonged hot period on the fatty acid (FA) composition in blood serum of dairy cows. Eighteen multiparous Holstein cows were randomly assigned to the hyperthermia group (HYP, n = 8) in August (summer season) and the control group (CON, n = 10) in October (autumn season). Blood from animals of the HYP group was collected in one heat wave, which was preceded by a long period of heat stress (HS, temperature-humidity index (THI ≥ 72)). Blood from cows of the CON group was collected under thermal comfort conditions (THI < 68). The spectrum of free fatty acids (FFA) in the blood serum was analyzed by gas chromatography. The concentration of FFA increased, including saturated FAs and monounsaturated FAs, in the blood serum of cows under conditions of prolonged HS. This was associated with the mobilization of FA into the bloodstream from adipose tissue, as a consequence of negative energy balance. An increase in the ratio of n-6/n-3 polyunsaturated FAs may indicate biomembrane dysfunction and adversely affect dairy cows. This study showed that prolonged periods of heat can affect the FA composition of blood. How much this leads to changes in the FA composition of milk and the quality of food products remains to be seen in further research.

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Score productive longevity of dairy cattle is an important scientific and practical importance. It is known that among genetic factors, significant effects of linear affiliation of their parents. It is demonstrated that effective breeding subject to strict compliance with the screening system, selection and evaluation of animal breeding values reported by domestic and foreign authors. The purpose of the work was to study the influence of linear membership on productive longevity and lifetime milk productivity of Holstein cattle of European breeding. Studies carried out on cows Holstein breed using data management system dairy cattle breeding "Orsek". Found that targeted breeding work and selection in a herd of imported European cattle breeding Holstein using information systems selection bulls MAR company CRI meets the latest requirements of the ICAR and Subcommittee on the unified international assessment of manufacturers (Interbull) contributed to a change in the number of separate lines among the cows first generation. This has led to an increase in the percentage of manufacturers lines daughters Valiant 1650414.73, Starbuc  352790.79, as well as Cheef 1427381.62. on the basis of the desired economic-useful signs. It is established that the value of productive longevity of cows depending on linear conditioning averaged 3.1 ... 3.9 lactations. By this measure, the daughter of Starbuck's lines were superior animals Holstein breed other lines by the number of lactations: Chevalier – 0.1 or 2.6% (td = 0.25; P ≤ 0.95); Bell – 0.5 or 14.7% (td = 0.95; P ≤ 0.95); Valiant – at 0.8 or 25.8% (td = 1.52; P ≤ 0.95); Eleveyshn – 0.8 or 25.8% (td = 1.91; P ≤ 0.95); Cheef – 0.5 or 14.7% (td = 1.27; P ≤ 0.95). It has been proven that milk productivity and milk quality of the imported Holstein cows and their offspring of domestic generation attributable to linear. The highest lifetime yield of Holstein breed cows had Starbuck lines, which outnumbered their import contemporaries other lines: Chevalier – 2818.7 kg or 8.2% (td = 0.46; P ≤ 0.95); Bell – 3404.5 kg or 10.1% (td = 0.61; P ≤ 0.95); Valiant – 5553.8 kg or 17.5% (td = 1.26; P ≤ 0.95); Eleveyshn – 7368.9 kg or 24.6% (td = 1.78; P ≤ 0.95); Cheef – 5500.5 kg or 17.3% (td = 1.38; P ≤ 0.95). The father's genotype had a significant impact on the quality of the milk. It should be noted that cows Starbuck's line differed relatively high fat content in the milk. By this measure the superiority of animals this line over imported cows other lines: Chevalier – 0.5% (td = 2.38; P ≥ 0.95); Bell – 0.2% (td = 1.38; P ≤ 0.95); Valiant – 0.6% (td = 2.78; P ≥ 0.95); Eleveyshn – 0.4% (td = 3.23; P ≥ 0.99); Cheef - 0.2% (td = 1.44; P ≤ 0.95). However, large protein content in milk cows belonging to different lines of Bella, who on this indicator had superiority over animals other lines: Chevalier – 0.2% (td = 1.03; P ≤ 0.95); Starbuck – 0.1% (td = 0.59; P ≤ 0.95); Valiant – 0.5% (td = 2.31; P ≥ 0.95); Eleveyshn – 0.2% (td = 1.85; P ≤ 0.95); Cheef – 0.1% (td = 1.15; P ≤ 0.95). It should be noted that only the cows first generation Valiant lines and Eleveyshn marked positive relationship between life and the content of cows in milk fat and protein (r = +0.17 ... +0.40), which may indicate the possibility of holding breeding work to improve these symptoms. So in the breeding work it is advisable to use manufacturers of prominent lines that combine high breeding value on productivity of daughters with improving effect on the duration of their use. The results of the research show that the effective use of well-known manufacturers and imported Holstein breed brood in breeding work with dairy cattle of Ukraine. However, shortening the productive use of animals in conditions of industrial technology should serve as a stimulus to study and find ways to solve this problem.

The aim of the research was to evaluate the influence of the type of the nervous system on the productive and reproductive qualities of animals. The type of nervous system (strong, weak) of cows of the Ukrainian red dairy breed was determined by the index of the nervous system, which is based on the variability of the fat content in the morning milk yield after changing the conditions of cows keeping. Under the new conditions of keeping cows with a strong type of nervous activity, the coefficients of variability of the morning milk yield and the fat content in milk practically remained at the same level (their slight increase was noted at the level of 4.5 and 3.1%). In cows of a weak type under similar conditions of keeping, a significant increase in the variability of milk yield (by 53.6%) and fat content in milk (by 266.7%) was found. In animals of both types, in the first days of summer-camp keeping, in comparison with winter-stall keeping, there was an increase in milk yield and a decrease in fat content in milk. In cows of the strong type, the fat content decreased by 0.08% and of the weak type by 0.12%. The average index of the nervous system type in animals of the strong type is 1.18, and in cows of the weak type 2.71 (P> 0.999). Before and during milking, the pulse rate in the cows of weak type was higher by 8.0 and 10.8 beats / min. (P> 0.999), compared with the strong type. The animals of strong type of the nervous system, in comparison with the weak type, had a smaller thickness of the concha and skin, a higher pulse and respiratory rate, and a lower rectal body temperature. In cows of a strong type of the nervous system in postnatal ontogenesis, the formation of productive traits took place more rapidly and they better adapted to the conditions of the external environment. This is evidenced by their high coefficient of relative decline in the growth at the age of one (85.0) than in animals with a weak type of nervous system (78.5). The advantage of cows with a strong type of nervous activity over a weak one in milk yield was 348 kg (P>0.95) and in milk fat 8.0 kg. The service period in animals with a strong type of nervous activity was 6.3 days shorter. The animals with a strong type of nervous activity during the first lactation had a higher adaptation index compared with animals of a weak type. The difference for this indicator is 0.49 (or 3.7%). They also had a higher productivity index for the first (3.1%) and second (4.0%) lactation. Thus, the typological features of the nervous activity of cows affect the formation of the most important functions of the body, which can be used in breeding work to improve the herd.