Amount Of Milk Fat Research Articles

Analysis of dairy productivity of cows of ukrainian brown dairy breed of different genotypes by kappa-casein

In the herd of cattle of the Ukrainian Brown Dairy breed studies were conducted, the purpose of which was to study the influence of the genotype of cows by kappa-casein on the indicators of their milk productivity. Genotyping of 29 heads of cattle. Determination of the polymorphism of the kappa-casein gene was performed in the genetic laboratory of the Institute of Physiology n.a. Bogomolets of NAS using molecular biological analysis of allele recognition by polymerase chain reaction (PCR) in real time. Allele A had a slightly higher frequency - 0.517 compared to allele B - 0.483 at the locus of the kappa-casein gene, although it was not significant. As a result, the proportions of AA and BB genotypes were high (38 and 34%, respectively). The performed genetic-statistical analysis revealed an excess in the kappa-casein locus of homozygous variants AA and BB and a lack of heterozygous AB. The degree of homozygosity, which is 50.1%, indicates a sufficient level of consolidation in the studied population of cattle. The number of effective active alleles in the kappa-casein locus of cows of the Ukrainian Brown Dairy breed is 1.99, with the maximum value of the level of polymorphism possible at a two-allele locus of 2. A negative heterozygosity test (HT) indicates a lower proportion of actual heterozygotes relative to the proportion of theoretical heterozygotes. The reason for the existing genetic structure of the herd of Ukrainian Brown Dairy breeds by the kappa-casein locus was the use of Swiss cattle breeders, most of which were not evaluated by the genotype of the kappa-casein gene. Studies of the level of milk productivity of cows of different genotypes by kappa-casein in the first lactation did not reveal a significant difference. At the same time, heterozygous (AB) animals were inferior to homozygous (AA and BB) in terms of milk yield, and animals with AA and AB genotypes were preferred in terms of quality. For the best lactation, a significant difference was found in the amount of milk yield and the amount of milk fat. Homozygous animals (AA and BB) significantly (p <0.05) outperformed heterozygous (AB) in milk yield, by 1091 and 922 kg, respectively. Animals with heterozygous AB genotype in terms of the average amount of milk fat were significantly inferior to homozygous AA and BB animals (p <0.05). The small number of experimental animals was one of the reasons for the discrepancy between the results of research and the data of other scientists. Key words: breed, milk yield, fat content, protein content, kappa casein, genotype, allele.

Збереження генофонду та підвищення продуктивності худоби білоголової української породи

Goal. To determine the level of homozygosity of the active part of the population of the white-headed Ukrainian breed for one generation and 50 years of reproduction, as well as the possibility of using inbreeding to preserve the gene pool of the breed and increase animal productivity. Methods. The study was conducted on animals of the white-headed Ukrainian breed, divided into outbred and inbred. The first series of experiments determined the influence of unrelated and related selections of parental pairs, the second series studied the influence of the origin of the bull (the father of the offspring) on the manifestation of signs of productivity in outbred and inbred cattle. In both experiments, the group of inbred included animals whose inbreeding coefficient was Fx = 0.39–29.7%, and the group of outbred — who had no common ancestors in the pedigrees. In the third series of experiments, the influence of different degrees of inbreeding (moderate, close, and very close) on the milk productivity of cows of a specific origin was determined, for which the descendants of the bull Zlaka UA 673 were divided into 4 groups. Live weight of cows, milk yield for lactation, content and amount of milk fat in milk, age of the 1st insemination were determined. The level of inbreeding growth was calculated for one generation and 50 years of reproduction. Results. The advantage of inbred heifers in live weight in different growing periods compared to outbred individuals was established, especially at the final stage, which accelerated their physiological and economic maturity. The effect of inbreeding on the reduction of milk production in cows of individual bulls without statistically significant difference with outbred animals had been proved. There was a direct, medium and weak connection between milk yield during the 1st lactation with age and live weight at the 1st insemination. It was proved that the increase of the inbreeding coefficient from Fx = 0.78–2.93% to Fx = 12.5–29.7% in the daughter offspring of the bull Zlaka UA 673 significantly increased milk productivity for 1–2 lactations. It was found that in the modern, active part of the population of the white-headed Ukrainian breed, inbreeding can increase by 1.68% in a generation, and by 16.5% in 50 years of reproduction. Conclusions. When breeding Ukrainian white-headed cattle, which currently has 300 cows and 11 bulls, it is impossible to avoid a related selection of parent pairs. With this in mind, inbreeding can be used as a method of preserving the gene pool of white-headed cattle in the context of preserving the biodiversity of wildlife. The use of close inbreeding is preferable to moderate and close.

The relationship of economic and useful traits in the Ural type cows of the black-and-white breed

In the Sverdlovsk region, holsteinized black-and-white cattle of the Ural type are bred. All cows have high productivity indicators; the best milk yields are distinguished by the animals of the Vis Back Ideal line, which surpass their peers by 99 (Reflection Sovering line) and 1477 kg (Montwick Chieftain line) or by 0.9 – 13.7%. In the second case, the difference is significant at P≤0.01. According to the FMF in milk, higher values were observed in cows of the Montwick Chieftain line – 4.03±0.003%. They significantly surpass cows from other lines by 0.04 – 0.07% at P≤0.01, which did not affect the output of nutrients with milk. There is a stable high correlation between cow milk yield and milk fat yield with milk. The correlation coefficients approach one. A negative correlation was found between milk yield and fat mass fraction, which ranged from low (-0.03, Montwick Chieftain line) to medium (-0.34, Vis Back Ideal line). The average positive relationship between the fat mass fraction in milk and the amount of milk fat was found in cows of the lines of the Reflection Sovering and Vis Back Ideal

EFFECT OF PROLACTIN (PRL) AND BETA-LACTOGLOBULIN (BLG) GENES ON INDICATORS OF DAIRY PERFORMANCE IN COWS OF RED BELARUSIAN BREED GROUP

Studies show that according to the prolactin gene (PRL), the highest milk yield was determined in the first-calf heifers with the PRLAB genotype by 2.5%, and in cows of the second and third lactations – with the PRLAA genotype by 0.8-7.0%. In terms of fat and milk protein content, animals with the PRLAB genotype had higher rate than those with the PRLAA genotype by 0.1-0.2 pp, the second and especially third lactation animals having the most noticeable changes. For the beta-lactoglobulin (BLG) gene, animals with the BLGBB genotype had the higher rate of milk yield for 305 days of lactation, as well as the amount of milk fat and lactoprotein. With an increase in the lactation ordinal number, the difference in these indices between the BLGAB and BLGAA herdmates increased.

Impact of the Tirsana BSC energy supplement on the productivity of Ayrshire cows

Nowadays, a new science-based approach to animal feeding is required to create conditions for the full realization of their potential with intensive use of livestock. This research was an experimental test that aimed to evaluate effective feed intake of energy supplements TirsanaBSC by high-yield Ayrshire cows in the transit period. As a result of the supplement application the daily milk yield increased during 100 days of milking cows. The amount of milk fat and protein increased as well. There was an increase in carotene, glucose, pyruvic acid in the blood of experimental cows and reducing non-esterified fatty acids (NEFA). Adding the supplement Tirsana BSC to the diet of highly productive Ayrshire cows improved the quality of their colostrum.

ВЗАИМОСВЯЗЬ ГЕНОТИПОВ СОМАТОТРОПИНА И ЛЕПТИНА С ХОЗЯЙСТВЕННО-ПОЛЕЗНЫМИ ПРИЗНАКАМИ КРУПНОГО РОГАТОГО СКОТА В УСЛОВИЯХ ПАВЛОДАРСКОЙ ОБЛАСТИ

The article studies the polymorphism of BGH, LEP marker genes in Simmental cows. The association of polymorphism of the studied candidate genes with indicators of milk productivity and qualitative composition (protein content, amount of milk fat and protein) was studied. The desired genotypes of marker genes in association with economically useful features of Simmental cattle have been established. The interrelationships of economically useful features in animals of the Simmental breed were studied depending on the genotypes BGH, LEP. During the research, the results were obtained indicating a significant effect of different genotypes of genes BGH, LEP, exerted on the milk productivity of Simmental cows. The data obtained supplement and expand the already existing information about the forms of associative-useful features with different genotypes of BGH, LEP genes. The results can introduce into the program of selection and breeding activities for improving the genetic potential of Simmental cattle.

ANALYSIS OF COMPLEX GENOTYPES OF BETA- AND KAPPA CASEIN OF BULLS OF DAIRY BREEDS

Marker-dependent breeding is one of the most relevant areas for improving the dairy productivity of cattle. It allows the selection of parent forms at the gene level. The growing demands of the market for milk quality make it necessary to select dairy herds using genetic markers associated with qualitative characteristics of milk productivity. A topical issue in dairy cattle breeding today is the study of the relationship between hereditary factors that determine the types of proteins in milk. Casein is the main component of milk proteins and is represented by three fractions – alpha (CSN1S1), beta (CSN2) and kappa (CSN3). The content of individual casein fractions depends on the breed of cows. Genetic variants of beta-casein significantly affect human health, while kappa-casein is associated with the quality of milk and the greater suitability of milk for processing and cheese production.
 The aim of this work is to evaluate the genotype of sires approved for use in Ukrainian farms in 2020 based on beta- and kappa-casein genes.
 Materials and methods. The research was conducted by analyzing the catalog of bulls of dairy and dairy-meat breeds for breeding stock reproduction in 2020. Bulls were analyzed according to the genotype of beta – and kappa-casein of Holstein (n = 872), Simmental (n = 17), Montbellard (n = 3), (wro.synel.net; motbeliarde.org) Jersey (n = 59), Red Danish (n = 8), Red Norwegian (n = 7), Schwyz (n = 17), Aishir (n = 8) breeds, evaluated by offspring quality and genomic assessment. The website DairyBulls.com is used to analyze the results of the evaluation of bulls-producers on a set of characteristics. The research results were processed by mathematical statistics methods using the "Statistica-6.1" package in a Windows PC environment.
 It was found that the majority of bulls-producers approved for use were evaluated based on these genotypes. Depending on the breed, the number of bulls estimated by the studied characteristics ranged from 43 to 85%. Depending on the breed, from 2 to 16 different combinations of beta- and kappa-casein genotypes were identified. The frequency of occurrence of the desired complex genotype A2A2/BB, depending on the breed, was in the range of 0.0 to 75.0%. Holstein bulls of the desired A2A2/BB genotype were estimated to be superior to bulls of some other complex genotypes in terms of daughter milk yield, the amount of milk fat, milk protein, lifetime profit indices, cheese profit, and milk profit.
 Therefore, the use of sperm production of bulls with the A2A2/BB genotype will improve the economically useful characteristics of offspring, and will further increase the number of livestock with the desired complex genotype.
 Summary.
 1. Taking into account the data of many domestic and foreign scientists who claim that the genotype of animals by the beta – and kappa-casein polymorphism affects the qualitative composition of milk, it is necessary to have in herds the necessary number of animals carrying the A2 allele of beta-casein and the B allele of the kappa-casein gene. The desired breeding parameters of the herd can be achieved by using bulls with BB genotypes for kappa-casein and A2A2 for beta-casein. Correction of the bulls-producers selection system can only be carried out if the breeding stock of the herd is genotyped according to the polymorphism of the beta-and kappa – casein genotypes. Holding this event will increase the protein content and will improve cheese suitability of milk of cattle of future generations.
 The use of bulls-producers without taking into account their genotypes for the casein fractions described above and the lack of polymorphism control of these genes among cows can lead to a decrease in the frequency of desired genotypes in the herd and a decrease in the technological qualities of milk as raw materials.
 2. The created database of bulls-producers approved for use in Ukraine, evaluated by the beta-and kappa – casein genotypes, allows us to establish a positive perspective on the possibility of forming staffed herds of animals with the desired complex A2A2/BB genotype in Ukraine.
 3. It was found that bulls of dairy breeds have different frequencies of beta – and kappa casein alleles. The part of bulls-producers of the desired complex genotype A2A2/BB of Holstein breed is 8.49%, Holstein Red-pockmarked – 2.94%, Schwyz – 75%, Jersey – 13.79%, Red Danish – 12.5%, Red Norwegian – 20.0%, Montbellard – 25%. Among animals of Simmental and Aishir breeds – bulls with the desired complex genotype A2A2/BB were not detected.
 4. Bulls of the desired complex genotype A2A2/BB according to the indicators of milk yield of daughters, the amount of milk fat, milk protein, indices of lifetime profit, profit for cheese, profit for milk were dominated bulls with separate complex genotypes CSN2-CSN3

ACTIVE PART OF POPULATIONS OF TRANSBOUNDARY AND DOMESTIC BREEDS OF DAIRY AND COMBINED CATTLE BREEDING OF UKRAINE

Today in Ukraine, according to the State Register of Breeding Subjects, 13 dairy cattle breeds have been registered in animal husbandry. Conventionally, they can be divided into transboundary ones, such as Ayrshire, Angler, Holstein, Simmental, Brown Swiss and Red Polish, and domestic – Ukrainian Whiteheaded, Lebedyn, Red Steppe, Ukrainian Brown Dairy, Red, Black-and-White and Red-and-White Dairy cattle.
 The breeding part of the dairy cattle population is 299908 breeding animals, including 129557 cows, which are concentrated in 321 breeding subjects. The share of domestic breeds is at the level of 67.9%. A tendency towards an increase in the number of animals in the population of transboundary breeds by 56724 animals was noted, with a simultaneous reduction in domestic breeds by 221980 animals. The main part of the transboundary breeds is Holstein (83%) and Simmental (11%), and in the domestic breed population, it is Ukrainian Black-and-White (71.5%) and Red-and-White (19.8%) dairy cattle. Local domestic breeds (Lebedyn, Red Steppe, Ukrainian Brown Dairy) occupy 2.8%.
 The level of milk yield of the studied cows of the breeding part of the population of domestic and transboundary breeds is quite high and is in the range of 7242 ... 4309 kg. During the study period, there is a gradual increase from 2002 to 2019 for the milking, fat content and the amount of milk fat in cows of a population of transboundary and domestic breeds, which is respectively 3382.1 kg 0.16%; 140.7 kg and 3052 kg 0.06%; 118.1 kg. In 2019, the highest milk yield in the population of transboundary breeds was noted among Holstein cows (8679 kg) and Brown Swiss (8789) breeds, and in domestic – Ukrainian Black-and-White (7514 kg) and Red-and-White (7005 kg) dairy breads. The fat content in milk is more than 4% in cows of local breeds of Ukraine.
 An analysis of the level of milk yield of cows for the studied periods showed a decrease in the number of farms with a yield of 5 thousand kg or less. So, in 2002, the share of farms breeding transboundary breeds was 70%, then in 2019 only 13%, and in domestic from 83% to 16%. The average milk yield of cows of more than 10000 kg was recorded in 17 breeding farms.

Evaluation of highly productive cows by selection and genetic parameters

Under the conditions of intensive technologies used in production of livestock products, the main selection feature that characterizes the economic feasibility of dairy farming and breeding value of animals is milk productivity. One of the factors that affects, not only the economy of production, but also the improvement of herds and breeds of cattle, is the use of highly productive cows. Therefore, the aim of our research was to assess the level of development of productive traits in Holstein cows under the conditions of intensive milk production technology, according to selection and genetic parameters. To conduct the study, a group of 1089 first-born cows was formed with the help of the Dairy Comp program and Microsoft Excel. The material for the research was the milk productivity of Holstein cows during the first three lactations. The level of development of selection traits in animals was determined by selection and genetic parameters. It was found that from the sample n = 1089 to the group of highly productive animals (“>10560”) were included 266 cows, and low-productive animals (“<8706”) – 249 first-borns. They had an average milk yield for the first lactation, 11439 kg of milk with a fat content of 3.96 % and 7737 kg of milk and 3.95 %, respectively. There is a difference in milk yield, milk fat and protein between the groups of cows “>10614” and “<8706”, but there is a general tendency towards changes in productivity with age. Based on the data of milk recurrence and the amount of milk fat of high-yielding cows (group “>10614”), it was found that higher values of the coefficient are characteristic of lactations I–III (rw= 0.105; rw= 0.135). As a result of comparative analysis it was found that low-yielding animals (group “<8706”) were characterized by higher recurrence rates for I–II and I–III lactation (rw = 0.345;rw = 0.316;rw = 0.320 and rw = 0.664;rw = 0.646;rw = 0.651, respectively). Higher rates of recurrence of traits of milk productivity are the characteristic of low-yielding cows (group “<8706”), i.e. they had more consistency of traits during different lactations and animals with a high level of productivity did not differ in age constancy. At a high level of milk yield in cows of group “>10614” appeared a negative correlation of low and medium level (r = -0.423). It was also found a negative correlation of low and medium level between milk yield and protein content in milk (r = -0.007… -0.332). At lower milk yields, there is no negative correlation between milk yield and fat content in milk. Thus, the existence of a negative correlation between milk yield and fat content in milk at a high level of animal productivity, and between milk yield and protein content in milk at both high and low levels of cow productivity was proved.

FREE FAT IN MILK AND CHEESE PRODUCTS: INFLUENCE ON QUALITY

The theoretical and practical aspects of the formation of free fat in milk, cheese and cheese products with vegetable fats are considered. The amount of free fat in milk depends on the integrity of the fat globules membranes, which are affected by: ineffective emulsification of fat during the synthesis of milk in the cow’s udder (authentic fat) and physic-mechanical factors in the milk processing after milking (destabilized fat). Free fat, primarily subjected to oxidative processes and lipolysis, reduces the quality and ability to store milk. For cheese products, the presence of free fat, available for lipolysis and oxidation, is a prerequisite for obtaining high-quality products. Characteristics of the production of cheese products with vegetable fats, providing for the preliminary emulsification of vegetable fat in skim milk, contribute to the formation of denser membranes on the surface of fat globules, consisting mainly of casein micelles and whey proteins. This is the reason for the formation of a more closed structure of the fat phase with low availability of fat for enzymes and oxidizing agents. The low availability of fat in the structure of cheese products with vegetable fats is one of the factors that worsen their organoleptic characteristics. In order to increase the amount of available fat in the production of cheese products with vegetable fats, it is advisable to use additional enzyme preparations or cultures of microorganisms that activate proteolysis and lipolysis.

ЭФФЕКТИВНОСТЬ ПРИМЕНЕНИЯ ДОБАВКИ НА ОСНОВЕ МОДИФИЦИРОВАННОГО ДИАТОМИТА В МОЛОЧНОМ СКОТОВОДСТВЕ

The manifestation of mineral deficiency in the body of animals contributes to a decrease in their productivity and the development of diseases such as perversion and loss of appetite, anemia, endemic goiter, rickets, and osteoporosis. One of the ways to solve the problem of mineral insufficiency is the scientific search and development of advanced formula of feed additives based on natural minerals processed by high technologies. The aim of this study is to determine the effectiveness of using modified diatomite as a feed additive for dairy cows. The exeriment was carried out in Ulyanovsk region during 100 days. We formed groups of animals of 50 cows, the 1st group (control) did not receive additives, but only a household diet, in the 2nd group an additive based on modified diatomite was additionally introduced into the diet in a mixture with feed at the rate of 250 g/head/day, . For the physiological experiment, 5 cows were selected by the method of pairs of analogues. It was established that the introduction of additives based on modified diatomite into the diet of cows improves the morphological composition of their blood. Intake of the additive increases milk yield by 24.7% at p<0.05, the amount of milk fat by 16.2 % compared to the control. The effect of afteraction after stopping feeding the additive was revealed. The use of an additive based on a modified mineral is a cost-effective measure that reduces feed costs and gets additional profit. The average daily yield of natural milk increased by 8.2 % for 1 ruble, and a profit of 4.30 rubles was received . There was a decrease in feed costs for the production of 1 kg of natural milk, up to 0.85.

Phenotypic and genetic parameters of milk yield traits in first-calf heifers of Holstein-Friesian breed

The objective of this paper was to study variability, heritability and correlation of the three production traits in 1409 first-calf heifers of Holstein-Friesian breed; including the determination of the quantity of milk during lactation (ML), the quantity of milk fat during lactation (MM) and the quantity of protein during lactation (PR). According to the obtained results it could be concluded that there were statistically significant differences (P<0.01, P<0.05, P<0.001) between ML, MM and PR regarding the effect of season of the first calving and the length of the first lactation. In addition, there were also significant differences (P<0.01, P<0.001) between ML and PR with respect to the effect of farm on which animals were raised, while on MM variability the year and age at first calving had a significant effect (P<0.05). A share of Holstein genes and the ration which animals were fed had no effect (P>0.05) on variability of any of the examined traits, while the farm on which animals were raised had no effect (P>0.05) on MM, and year and age at first calving did not demonstrate (P>0.05) statistically significant effect on ML and PR. By applying the animal model, based on the use of kinship matrix which involved 3867 animals, by help of REML methodology following heritability coefficients were evaluated: ML h2= 0.25; MM h2= 0.40; PR h2= 0.37. Coefficients determined for genetic and phenotypic correlations indicated existence of complete and positive correlations between these traits the interval of values being from rg = 0.96 between ML and MM to rg = 1.00 between ML and PR.

Свойства вымени и продуктивное долголетие коров разных пород при интенсивной технологии доения

Abstract. The aim of the research is a comparative assessment of the morphological and functional properties of the udder, productive longevity of cows of Black-Mottled and Simmental breeds. Methods. The work was carried out on the basis of an agricultural enterprise of the Tyumen region, where a loose method of keeping cows and voluntary milking by a robot is used. In the first group – cows of Black-Mottled breed, in the second – Simmental. Results. Cows of the first group of the Black-Mottled breed had a uniformly developed udder with an index of 45.1 % and were superior to animals of the second group of the Simmental breed: in girth by 7.2 cm (5.4 %) (p < 0.001) and width by 1.0 cm (5.0%) (p < 0.001). The indicator characterizing the capacity of the udder in animals of the black-mottled breed is greater than in simmentals by 295.2 cm2 (10.0 %) (p < 0.05). The difference in the rate of milk yield of cows was 0.05 kg / min (2.3 %) in favor of simmentals. The period of production use of Black-Mottled cows is longer than this indicator in simmentals by 0.4 lactation (p < 0.001). Animals of the Black-Mottled breed gave 2471.0 kg (p < 0.001) more milk over the entire period of use compared to animals of the Simmental breed. In addition, in Black-Mottled cows, the amount of milk fat and milk protein during the life period exceeds simmentals by 86.3 and 72.3 kg (p < 0.001). Novelty. When using the developed method of selecting highly productive cows, it makes it possible to get more milk from cows per day by 1.4 kg (6.7 %), for 305 days – by 268.1 kg (5.4%), for the period of life – by 1684.4 kg (9.7%). This method allows you to extend the period of economic use of the dairy herd by 0.4 lactation (14.8 %).

Inheritance of allelic variants of the kappa-casein gene by cows

The inheritance of allelic variants of the kappa-casein gene from bulls with different genotypes and their influence on the milk production of daughters were studied. For research, PCR diagnostics of daughters in the herds of black-and-white cattle at the farms “Azeleevo” and “Vakhitovo” (OJSC “Red East Agro”) was carried out, the fathers were two bulls LADDIE 135797213 with a genotypes CSN3 AB and LOMAX 10785322 with a genotype CSN3 BB. Based on the results of genotyping, the frequency of occurrence of genotypes AA, AB, BB kappa-casein and allelic variants A and B in daughters was calculated. The bull with the CSN3 AB genotype produced the largest number of offspring with the CSN3 AA genotype 50.0-51.8 %, and the bull with the homozygous BB genotype produced 24–25 % of daughters carrying the BB variant and 75 -76 % of the AB genotype. The frequency of occurrence of the Kappa-casein allele in the daughters of bulls with the genotype CSN3 BB was 0.63, which is almost 2 times more than the allele A. When comparing heifers with the same genotype (CSN3 AB), it was found that at the Azeleevo farm, the daughters of the bulls having the genotype BB of kappa-casein are superior to cows born from bulls with the genotype AB by the milk yield (+36 kg), mass fraction of fat and protein (+0.01 %), the amount of milk fat (+2 kg) and protein (+2 kg). In the group of first-calf heifers with the BB genotype, daughters of the producer with the BB genotype are superior by the milk yield (+ 175 kg), the mass fraction of fat in milk (+0.1 %), the amount of milk fat (+12 kg), the mass fraction of protein in milk (+0.09 %), the amount of milk protein (+11 kg). At the Vakhitovo farm, similar results in the group of CSN3 AB heifers born from the bulls with the BB genotype was observed

ИЗУЧЕНИЕ ПРИЗНАКОВ МОЛОЧНОЙ ПРОДУКТИВНОСТИ У КОРОВ АЙРШИРСКОЙ ПОРОДЫ ПЛЕМЕННОГО ХОЗЯЙСТВА ЛЕНИНГРАДСКОЙ ОБЛАСТИ

In this article, studies the dynamics of indicators of the main signs of milk productivity over 305 days 7 lactations in 240 cows of the Ayrshire breed. The average values for milk yield, the mass fraction of fat and protein, the amount of milk fat and protein, the range between the maximum and minimum values were calculated and studied, and the stand-ard deviation according to the characteristics stud-ied was established. The average milk yield was higher in the 5th and 6th lactation and amounted to 8412 kg and 8962 kg; the maximum% of fat was in the 7th lactation - 4.2%, and% of the protein in the second - 3.46% and also in the last 7th lactation -3.43%. The value of the mass fraction of fat was maximum in the 1st lactation - 1.2; and the mini- mum at the 6th lactation is 0.05. The value of the mass fraction of protein was maximum in the sec-ond - 0.74 and minimum in the 7th lactation -0.24. He overall picture for these indicators represents the horizontal trend lines in the diagrams, which indicates a slight deviation of the values relative to the average for all lactations. The yield of milk fat and protein was maximum in the 6th lactation - 345.9 kg and 289.47 kg, respectively. The stand-ard deviation by milk was 568.6; by mass fraction of fat 0.09; by the mass fraction of protein 0.08; by the amount of milk fat 26.4; by the amount of milk protein 16.9; which means the uniformity of the average values for these indicators. It can be con-cluded that the selection of cattle in this complex was progressive, because led to stably high pro-duction in animals over 7 lactations.

Productive longevity of white-and-black cows of different genotypes CSN3 and DGAT1

The article studies the duration of use and life-long productivity black-motley breed cows with different allelic variants of the kappa-casein and diacylglycerol O-acyltransferase genes. The research consists the data study on cows dropped out the herd during 2012–2016 in the Dusym LLC of Atninsky District in the Republic of Tatarstan. The cows were previously genotyped for CSN3 and DGAT1. The herd of black-and-white cattle consisted the genotypes CSN3 AA and DGAT1 AK with a frequency of 60.9 and 53.5 % and less often CSN3 BB and DGAT1 KK – 4.0 and 6.3 %. Moreover, the frequency of occurrence of the desired B allele of the CSN3 gene was 0.22, and the K allele of DGAT1 was 0.33. Cows with the CSN3 AB genotype reliably surpass animals with the CSN3 AA genotype in the duration of use by 0.39 lactations (P <0.05), life-long milk yield by 2401 kg of milk (P <0.05), and the amount of milk fat by 90 kg (P <0.05), mass fraction of protein in milk – by 0.04 % (P <0.01), the amount of milk protein – by 83 kg (P <0.05). Animals with the DGAT1 KK genotype also have an excess over other groups of cows in terms of productive longevity, but the difference is significant only in fat milk (P <0.01–0.001).

РЕЗУЛЬТАТЫ СЕЛЕКЦИИ ЧЁРНО-ПЁСТРОГО СКОТА ПРИ ИСПОЛЬЗОВАНИИ ПОТЕНЦИАЛА ГОЛШТИНСКОЙ ПОРОДЫ

The share of genes of Holstein breed was 76.8% in the herd. It was found that during the research period, the normal distributions of milk productivity traits were observed in the herd. The number of cows in the herd decreased, but their breeding qualities increased. The main reason for which animals were culled from the herd was their gynecological diseases (in some years, up to 175 to 188 heads were culled). The protein content in milk varied from 2.90 to 3.39%. Most cows produced milk in which the protein content was at a level of 3.00 to 3.19%. The herd showed positive correlations between the yields of mothers and daughters for the 305-day-long period: 0.234 for the whole herd, 0.517 for the group of cows with 50% of Holstein breed (HF) genes, 0.098 for the group with 51-75% of HF genes, and 0,189 for the group with minimum 76% of HF genes. For the herd, the heritability coefficient for milk yield for the 305- day-long period (h2) was 0.468. The percent of the protein content in milk produced by cows with 50% of Holstein genes had a high heritability coefficient of 0.668. Only cows of the M. Chieftain line showed positive correlations between the fat content in milk produced by mothers and daughters, and positive correlations between the protein content in milk produced by cows of the W. B. Ideal and M. Chieftain lines was found. With an increase in percent of Holstein breed genes (HF) from 25 to 75% and more, there were no significant differences in milk yield among first-calf cows (they amounted to 5,424 ± 83 – 5,520 ± 116 kg of milk). The percentage of fat and protein in milk for the whole herd was positively interconnected (r = + 0.460). On average, daughters exceeded their mothers by 23.3% in terms of milk yield and by 2.0% in terms of the percentage of fat content in milk (of the trait value). The quantity of milk fat and protein increased by 25.8 and 22.5%, respectively. Based on the research results, it has been concluded that the Holstein breed has a positive effect on the productive traits of dairy cattle, but technology optimization is required to continue selection activities.

ВЛИЯНИЕ ГЕНОВ ДИАЦИЛГЛИЦЕРОЛ О-АЦИЛТРАНСФЕРАЗЫ 1 (DGAT1) И СОМАТОТРОПИНА (GH) НА ПОКАЗАТЕЛИ МОЛОЧНОЙ ПРОДУКТИВНОСТИ КОРОВ КРАСНОЙ БЕЛОРУССКОЙ ПОРОДНОЙ ГРУППЫ

The work presents the results of studies on the influence of diacylglycerol O-acyl transferase 1 (DGAT1) and somatotrophin (GH) genes taking into account their polymorphism on the milk productivity of red Belarusian cows. The object of the research was biological material from cows of red Belarusian breed contained in the USP Novi Dvor-Agro of the Svislochsky district of the Grodno region. DNA diagnostics of genotypes by the genes diacylglycerol O-acyl transferase 1 (DGAT1) and somatotrophin (GH) were carried out using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). As a result of the research carried out on the population of cows of the red Belarusian breed, the polyforphism of the gene somatotrophin (GH), represented by two alleles - GH L and GH V , with three genotypes GH LL , GH LV and GH VV identified. Among the test animals, individuals with a GH LL allele variant of 66% were more likely to cows, the GH LV was identified in 32%, and the GH VV was detected in only 2% of cows. By the gene diacylglycerol O-acyl transferase 1 (DGAT 1) polymorphism was identification, all animals had only one genotype, DGAT1 KK . Results of studies conducted on the effects of diacylglycerol O-acyl transferase 1 genes (DGAT1) and somatotrophin (GH) on milk productivity indices of cows of the red Belarusian breed group showed that in most cases animals with genotype GH LL outnumbered their peers GH LV and GH LL , in terms of 305 days of lactation per 0.9-10.1%, fat and protein flakiness per 0.2-0.3 p.p., the amount of milk fat and protein in milk per 1.1-9.1%. Evaluation of milk productivity of cows by the gene diacylglycerol O-acyl transferase 1 (DGAT 1) in dynamics shows that with increase of lactation sequence number milk productivity indices increase.

COMPARATIVE EVALUATION OF DAIRY PRODUCTIVITY OF COWS DIFFERENT LINES IN THE CONDITIONS OF THE OREL REGION

This article provides a comparative analysis of indicators of milk productivity and quality of the main lines of the Holstein breed cows in one of the pedigree reproducers of the Orel region – "ES "Streletskoye". Among the three evaluated lines, the best results were shown by Reflection Sovereign first-calf heifers, which exceeded in milk yield the first-calf heifers of the Montvi􀉫 Chieftain line by 13.6% and the first-calf heifers of the Vis Back Ideal line by 42.3% (P≤0.001). Milk production coefficients of first-calf heifers of the Montvi􀉫 Chieftain and Reflection Sovereign lines exceeded those of the Vis Back Ideal line by 27.1% and 42.0% (P ≤ 0.001). In turn, Reflection Sovereign first-calf heifers also exceeded first-calf heifers of the Montvi􀉫 Chieftain line by 11.7% (P ≤ 0.001). Similar results were obtained for the second and third lactations. In terms of AMF and AMP, the Montvi􀉫 Chieftain and Reflection Sovereign cows significantly exceeded Vis Back Ideal cows in 305 days of each of the first three lactations. In turn, Reflection Sovereign first-calf heifers outperformed the AMF and AMP of Montvi􀉫 Chieftain first-calf heifers. The highest positive correlation coefficients between the amount of milk fat and milk yield for 305 days of lactation were found in cows of the Vis Back Ideal line - from 0.36 to 0.90 (P≤0.05–0.001). Concerning the correlation between the amount of milk protein and milk yield for 305 days of lactation, cows of all studied groups showed high levels of interdependence, characterized by a high degree of reliability - from 0.45 to 0.99 (P≤0.01– 0.001). The total cost of base fat milk produced in 305 days of the first three lactations by Montvi􀉫 Chieftain and Reflection Sovereign cows (per head) exceeded the cost of milk produced by Vis Back Ideal cows by 87.7 and 144.1 thousand rubles, respectively.

PHENOTYPE FEATURES APPEARANCE OF DAIRY PRODUCTIVITY OF DIFFERENT UKRAINIAN DAIRY BLACK-AND-WHITE BREED COWS GENOTYPES

The main task of breeding in dairy cattle breeding is to raise dairy productivity of cows. Improvement of productive qualities of domestic dairy cattle with the use of Holstein breeders of high breeding value led to serious disadvantages, including impairment of animal health, reproductive capacity and quality of milk. Therefore, the purpose of our research was to examine the milk productivity of cows of different genotypes of the Ukrainian Black-and-White dairy breed and ascertain the relationship between quantitative and qualitative indicators of milk.
 Research conducted at agricultural limited liability company "Lishche" Lutsk district of Volyn region on cows of different genotypes of the Ukrainian Black-and-White dairy breed. 5 groups of animals were formed: I − cows with a proportion of Holstein breed 75% or less, II − with a share Holstein heredity 75.1–81.25%, III − Holstein heredity share 81.26–87.50%, ІV − with a share of the heredity of the Holstein 87.51–93.75% and V − with a share of the heredity of the Holstein more than 93.75%. Evaluation of milk productivity was carried out by milk yield, fat content in milk and the amount of milk fat for the first, second, third and highest lactations according to the data of zootechnical accounting.
 It was found that the largest number of animals under control (33.7%) was with the relative share of Holstein heredity of 81.26–87.50%, and the lowest (9.3%) was with relative share of the Holstein breed's heredity more than 93.75%. Analysis of the level of milk yield of cows of different genotypes showed that the increase of Holstein heredity increases milk yields, however, significantly reduces the fat content of milk. If the animals have a share of Holstein heredity up to 75% the milk yields was 5154, and the amount of milk fat − 199.7 kg, and cows with hereditary of 75.10–81.25% showed figures increased by 16.4 and 15.5%, with Holstein heredity 81.26–87.50% by 23.3 and 20.8%, Holstein heredity 87.51–93.75% for 26.1 and 23.2% and with Holstein heredity more than 93.75% for 34.8 and 31.4%, and fat content in milk, on the contrary, decreased, depending on the genotype of animals, by 1.6–2.3%. In all in the above cases, these changes were highly significant (P < 0.001).
 The effectiveness of breeding on increasing the milk productivity of cows depends on the efficiency of selection and selection of animals, taking into account the phenotypic and genetic correlation between economically useful features. It was found that the studied cows of all genotypes had highest highly reliable (P < 0.001) positive values of correlation coefficients between milk yield and milk fat (Table 2). These features are the most predicted because strong relationship between them (r = 0.912–0.987). There was also observed direct positive ligament (r = 0.039–0.533, P < 0.05–0.001) between fat content in milk and milk fat content, and mostly weak, and only in some cases correlation coefficients had average values. The cows of the studied genotypes had the lowest and for the most part unreliable values of relative variability by the milk yields and fat content milk. The heifers with conditional share of Holstein heredity, more than 75% had negative and weak relationship features, and the older cows were diversified from weak to average values.
 One of the reliable criteria for determining the level of heredity of features is the coefficient of frequency, which indicates their heredity stability in age. Coefficients of age-related frequency of milk yield, fat content of milk and the highest milk fat content of cows with a conditional share of Holstein heredity of up to 75% had indicating a higher degree of heredity of these features compared to high half-bred cows. With the increasing of heredity of the Holstein breed the genotype of controlled animals values were decreasing for the most part. The most significant and reliable (P < 0.001) genotype of animals affected milk yields (13.3–18.1% of the total variability of this feature), less – the fat content of milk (9.3–13.2% (P < 0.001) and the amount of milk fat (6.6–14.1% (P < 0.001), with the highest genotype influence on the studied features indicated in the first lactation.