scholarly journals Efficiency of breeding value genomic assessment of Holstein stud bulls in comparison with the assessment of the offspring quality

2021 ◽  
Vol 36 ◽  
pp. 06045
Author(s):  
Yulia Isupova ◽  
Maria Kuznetsova ◽  
Ekaterina Gimazitdinova ◽  
Ekaterina Martynova

A comparative analysis of the genomic assessment results of Holstein breed stud bulls and their assessment on the offspring quality in the conditions of the Udmurt Republic was carried out. To analyze the efficiency of using stud bulls assessed by different methods, data from farms included in the ranking of the top 20 enterprises in terms of milk yield per cow for 2019-2020 were used. A high indicator of the complex LPI index (over 2500) was obtained in three bulls at the beginning of the assessment, by the end of the assessment there were two bulls left - J. Koln-M 11087837 and Super 64131037. The outsiders of the LPI ranking were stud bulls Parlament 52800347 and Patrik 51660096. The indicators of the complex LPI index are at a decent level for all analyzed stud bulls. It should be noted that stud bulls, which had the least change in the LPI index from April 1, 2014 to December 1, 2017, performed well. Bulls, which initially had overestimated results on this indicator, subsequently gave a sharp decline in the LPI index. The value of milk productivity of the evaluated stud bulls' daughters ranged from 5930 to 6415 kg, the mass fraction of fat in milk - from 3.79 to 4.02%, protein - from 3.06 to 3.11%. In most cases, the genomic assessment does not accurately reflect the change in the productive quality of stud bulls' daughters. But in the case of a predicted change to a positive or negative side in the genome, it is also confirmed by the results of assessing the offspring quality, that is, if a bull is predicted to have a sharp decrease in milk yield, then negative indicators are observed according to the “daughter-peer” method.

2020 ◽  
pp. 80-86
Author(s):  
Т.В. Шишкина ◽  
Т.А. Гусева

В последние десятилетия широко используются комплексные индексы хозяйственной и племенной ценности животных, которые определяются на основе централизованного сбора и анализа данных о результатах использования быков в различных природно-экономических условиях. В нашей стране племенные достоинства быков-производителей оценивают по продуктивным качествам их дочерей. Исследования по оценке быков-производителей по качеству потомства были проведены в условиях ООО «УК «Русмолко» Пензенской области. С этой целью были отобраны быки-производители голштинской породы компании Alta Genetics Russia, проведена оценка племенной ценность быков по комплексу признаков, проанализирована продуктивность дочерей быков по производственным качествам, проведена оценка производителей сравнением дочерей со сверстницами, рассмотрена реализация генетического потенциала продуктивности коров, рассчитан удой дочерей быков в зависимости от NM$ и ППС. В результате исследований установлено, что при подборе производителей для закрепления за стадом допустимо руководствоваться показателями индекса пожизненной прибыли, при этом целесообразно руководствоваться расчетом прогнозируемого удоя по индексу передающей способности производителя. In recent decades, complex economic and estimated breeding values of animals have been widely used. They are determined on the basis of centralized collection and analysis of data on the results of using bulls in various natural and economic conditions. In our country, the breeding qualities of servicing bulls are assessed by the productive qualities of their daughters. Studies to assess servicing bulls by the quality of their offspring were carried out in the conditions of OOO (LLC) “UK “Rusmolko” of Penza oblast. For this purpose, servicing bulls of the Holstein breed of Alta Genetics Russia were selected, the breeding value of bulls was assessed by a set of traits, the productivity of the daughters of bulls was analyzed in terms of production qualities, the servicing bulls were assessed by comparing their daughters with the peers, the implementation of the genetic potential of cows’ productivity was considered, the milk yield of the daughters was calculated depending on NM$ (lifetime net merit) and PTA (predicted transmitting ability). As a result of the research, it was found that when selecting servicing bulls for assigning to a herd, it is permissible to be guided by the indicators of the lifetime merit index, it is also advisable to be guided by the calculation of the predicted milk yield according to the predicted transmitting ability index.


Author(s):  
Е.И. САКСА

Дана оценка племенной ценности (ПЦ) потомков быков-лидеров голштинской породы «новой» и «старой» селекций США в условиях хозяйств Ленинградской области. В среднем, повышение молочной продуктивности от использования импортной спермы 68 проверенных по качеству потомства быков составило +79 кг молока (10133 кг, 3,82% жира, 3,23% белка). Наиболее высокий показатель ПЦ по удою — у 18 потомков быков-лидеров «новой» селекции: +175 кг при одинаковом содержании жира и белка в молоке (10673 кг, 3,84% жира, 3,25% белка). У потомков быков-лидеров «старой» селекции ПЦ по удою была ниже и составила +53 кг молока (9989 кг, 3,81% жира, 3,22% белка). Выявлена положительная связь (P<0,001) между ПЦ потомков быков-лидеров, оцененных по геному в США и по качеству потомства в хозяйствах Ленинградской области: по удою +0,634; по содержанию жира в молоке — -0,476; по содержанию белка — +0,444. Приведены предварительные данные о сокращении генерационного интервала между поколениями геномно оцененных быков при использовании их в подборах пар в племзаводе. Выявлено, что при использовании геномно оцененных потомков быков-лидеров высокой ПЦ «старой» селекции можно избежать близкородственного разведения и обеспечить генетическое улучшение животных по селекционным признакам. Breeding value (BV) evaluation of the descendants of alpha bulls from the “new” and “old” USA’s selections of the Holstein breed under the conditions of the farms located in the Leningrad Region is presented. In average, the increase of milk yield due to the use of imported sperm of 68 bulls with the verified offspring quality amounted to +79 kg of milk (10133 kg; fat — 3.82%; protein — 3.23%). The highest BV parameter by milk yield was registered in 18 descendants of the “new” selection’s alpha bulls: +175 kg with similar fat and protein content of milk (10673 kg; fat — 3.84%; protein — 3.25%). BV of the descendants of the “old” selection’s alpha bulls by milk yield was lower and amounted to +53 kg of milk (9989 kg; fat — 3.81%; protein — 3.22%). A positive relationship (P<0.001) was identified between BV of the descendants of alpha bulls which were evaluated by genome in the USA and by the quality of offspring in the farms of the Leningrad Region: by milk yield — +0.634; by fat content in milk — -0.476; by protein content in milk — +0.444. Preliminary data concerning the reduction of the generation interval between the generations of genome-assessed bulls upon their use for the selection of pairs in the breeding plant was presented. It was found, that the use of genome-assessed descendants of “old” selection’s alpha bulls with the high BV parameter can be carried out avoiding closely related breeding and ensuring genetical improvement of animals by selection traits.


2021 ◽  
Vol 250 ◽  
pp. 172-177
Author(s):  
E. I. Anisimova E. I. ◽  
◽  
P. S. Katmakov ◽  
A. V. Bushov ◽  
◽  
...  

The paper presents results of assessing black-and-white bulls by the quality of the offspring with application of different methods. The evaluation of bulls was carried out with application of the “daughter-mother” method in the conditions of Volzhsky Research Institute of Hydraulic Engineering and Land Reclamation. The valuation showed that the bulls Aist 7 and Muscat 8 increased milk yield of daughters, in comparison with mothers, by 951 and 486 kg, or by 26.7 and 12.9%. The rest of the servicing bulls reduced milk yield of the offspring by 46 - 1019 kg (1.1 - 24.7%). When assessing the bulls using the “daughterpeer” method, the highest milk productivity was shown by the descendants of Sazan 25 and Aist 7 of Vis Back Ideal line, which surpassed their peers in milk yield by 273 and 419 kg, or by 3.8 and 5.7%, respectively. The producers Snop 57 (his 17 daughters had average milk yield of 4224 kg for the first lactation with milk fat of 3.80%) and Muscat 8 (with an average milk yield of daughters of 4254 kg , milk fat - 3.83%) are also of significant value for the breeding work of this farm. According to the assessment results, the producer Aist 7 was assigned to the breeding category of A1 of milk yield improvers. Bulls Sazan 25 and Muscat 8 are also rated as daughters’ milk yield improvers and are categorized as A2 and A3. All bulls evaluated by comparing daughters to the breed standards are improvers of daughters’ milk yield (+ 454-1860 kg).


Author(s):  
M. V. Abramova ◽  
S. V. Zyryanova

Breeding takes the main place in the complex of measures for intensification of dairy cattle breeding. A characteristic feature of breeding work is identification of the most valuable genotypes and their further use in cattle population. The Holstein breed is considered one of the most highly productive breeds, in many countries of the world it is used for the genetic improvement of local breeds. In this regard, a comparative assessment of methods for determining the breeding value of bulls of different genotypes obtained by interbreeding is relevant. The results of assessment of genetic superiority of the used breeding bulls in terms of milk productivity of daughters for the first lactation through interannual deviations of the homogeneous peers are presented, the best producers in all the studied herds are identified, it is established which breeds the best and worst breeding bulls belong to. The research revealed that 18% of bulls had genetic superiority at controlled farms (9% - Holstein breed, 6% - Yaroslavl crossbreeding bulls, 3% - Mikhailovsky type’s bulls), a negative value - 24% including 9% - Yaroslavl crossbreeding bulls, 9% - Mikhailovsky type’s bulls and 6% - Holstein bulls. A comparative evaluation of the two methods showed a high reliable positive correlation between results of Mikhailovsky type bulls and Yaroslavl crossbreeding bulls equal to 0.82 and 0.56, respectively, which indicates a high reliability of the method of genetic superiority index, which can be used to evaluate bulls during crossbreeding. It is possible to increase the genetic potential of herds by excluding producers with a negative genetic index. The obtained results are recommended to be used when mating bulls and for development of breeding programs for individual herds or entire population


Author(s):  
Н.А. ПОПОВ ◽  
В.Ю. СИДОРОВА

В статье рассмотрены цифровой формат оценки племенной ценности инбредных быков-производителей по качеству потомства и ее влияние на последующие поколения животных. Выявление инбредного гетерозиса у производителей помогает сделать оценку быков по качеству потомства более информативной за счет определения глубины изменения параметров генетической структуры популяции и степени увеличения частоты рецессивных генов в подконтрольных популяциях. Одной из причин значительной разницы в удое, МДЖ и МДБ российских и американских коров голштинской породы являлась их удаленность от родоначальника. Другой причиной считается стремление селекционеров к инбридингу на выдающихся предков, однако в случае инбредного гетерозиса высокие показатели родителей быстро затухают в последующих поколениях потомков. Исследования были проведены в хозяйствах Московской области малой и средней производственной мощности. Для сравнения проанализированы результаты оценки быков-производителей из США и других стран с высокоразвитым молочным скотоводством. Методами изучения были имитационный и регрессионный анализ данных первичного зоотехнического учета и собственных исследований. Эксперимент показал, что быки-производители с высокими степенями родства уменьшали изменчивость признаков молочности среди дочерей: по удою — на 77,9%; по МДЖ — на 33,4%; по МДБ — на 36,0%, по сравнению с отцами, имеющими низкие степени родства. При этом в их поголовье в первом поколении повышается генетический тренд по удою на 14,3—21,4%, а племенная ценность — на 10,8—26,8%. В настоящее время в зарубежных популяциях голштинской породы широко применяют геномный метод оценки племенной ценности, при котором не требуется информация о родословных животных и не учитывается степень их родства, что отрицательно влияет на получение высококачественного потомства. Повышение племенной ценности по признакам в популяции сыновей и внуков быков-лидеров породы угасает, если в генофонде родителей имел место инбредный гетерозис. The article considers of the inbred breeding bulls breeding value by offspring quality and its impact on subsequent generations of animals’ digital format assessing. Identification of inbred heterosis helps to make the bulls’ assessment by the offspring quality more informative, by determining the depth of changes in the genetic structure of the population parameters and the recessive genes at populations frequency degree increase controlling. One of the reasons for the significant difference in milk yield, MJ and MDB of Russian and American Holstein cows was their distance from the ancestor. Another reason is considered to be of the breeders to inbreeding for outstanding ancestors’ desire, but in the case of inbred heterosis, high rates of parents quickly fade in descendants in subsequent generations. The research was carried out in the farms of the Moscow region of small and medium production capacity. For comparison, the results of the evaluation of breeding bulls in the United States and other countries with highly developed dairy cattle breeding were analyzed. The research methods were simulation and regression analysis of primary zootechnical accounting data and authors’ own research. Experimental data showed that breeding bulls with high degrees of relation reduced the variability of milk production among daughters by milk yield in 77.9%: for MJ in 33.4%; for MDB in 36.0% in compared with fathers with relation’s low degrees. At the same time, in livestock’s first generation, the genetic trend in milk yield increases in 14.3—21.4%, and the breeding value in 10.8—26.8%. Currently, the genomic method of assessing the breeding value is widely used in foreign populations of the Holstein breed, which does not require information about the pedigrees of animals, and does not take into account the degree of their kinship, which negatively affects the production of high-quality offspring. The breeding qualities of the sons of the bull leaders of the breed are quickly disabled the surge of increased breeding value by signs in the population of sons and grandchildren of bulls-leaders of the breed is fading if inbred heterosis took place in the parents' gene pool.


Author(s):  
M. V. Voronov ◽  
N. A. Fedoseeva ◽  
T. N. Pimkina ◽  
O. V. Gorelik

The improvement of cattle of Black-and-White breed by mating of maternal stock with the sires of Holstein breed continues at the present time. Therefore, breeding in pedigree farms for the production of milk is carried out including the use of Holstein lines. The purpose of the work was to assess the milk productivity of cows of Black-and-White breed, with a high proportion of blood in Holstein breed, depending on their linear origin. In the herd of the breeding farm where the research has been carried out, the lines Reflection Sovereign 198998 and Wes Ideal 933122 occupy the dominant position in terms of the specific weight of cattle, followed by the line Montwick Chieftain 95679. The difference in milk yield between groups of cows of different lines was from 3,0 to 354 kg or 0,04 to 4,6 %. The highest milk yield was shown by the first-calf heifers of the line Wes Ideal 933122 – 7787±123,21 kg. In the milk of the first-calf heifers of the line Pabst Governor 882933 compared with herdmates of other lines the increased content of fat and protein has been noted,. The difference in the mass fraction of fat in milk was significant in favor of Pabst Governor 882933 cows (P ≤ 0,01–0,001). There was also the significant difference in the mass fraction of fat in milk between the groups of cows of the lines Montwick Chieftain 95679, Reflection Sovereign 198998 and Wes Ideal 933122 in favor of the latter at P ≤ 0,05–0,01. A definite association between milk yield and the mass fraction of fat in milk has not been established. There is a pattern of the positive association between the mass fraction of fat and the mass fraction of protein in milk and it is clearly seen that with the increase in the mass fraction of fat in milk, there is the increase in the mass fraction of protein.


2017 ◽  
Vol 54 ◽  
pp. 65-74 ◽  
Author(s):  
R. V. Milostiviy ◽  
L. V. Karlova

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.


Author(s):  
Е.С. МАСЛЕННИКОВА

Показана эффективность использования быков, оцененных по качеству потомства и геному, в хозяйствах Ленинградской области. В среднем повышение молочной продуктивности в условиях региона от использования импортной спермы 84 проверенных по качеству потомства быков составило +19 кг молока (10138 кг молока, 3,83% жира, 3,20% белка), 68 геномно оцененных быков — +24 кг молока (10568 кг молока, 3,85% жира, 3,23% белка). Наилучшие результаты при оценке по качеству потомства в хозяйствах Ленинградской области получены от импортных производителей с племенной ценностью более +600 кг молока (+218 кг молока по быкам, оцененным по качеству потомства, +120 кг молока по геномно оцененным быкам). Уровень племенной ценности по удою улучшателя Дэвиса 138027041 варьирует от +297 до +615 кг молока. В высокопродуктивных (10000 кг и выше) стадах превышение удоя над сверстницами было больше, чем в стадах с продуктивностью 8000 кг молока при коэффициенте повторяемости 0,85. Быки с высокой геномной оценкой (от +719 кг до +1137 кг молока) повысили удой дочерей, по сравнению со сверстницами, в хозяйствах Ленинградской области от +274 кг (Стерлинг 69701759) до +1063 кг (Салун 70358061). С увеличением геномной племенной ценности производителей наблюдается рост продуктивности дочерей в хозяйствах области на 1469 кг молока. Между оценками племенной ценности быков разными методами (в США метод BLUP, в Ленинградской области — «дочери—сверстницы») выявлена положительная связь по удою для быков, проверенных по качеству потомства, +0,54, имеющих геномную оценку — +0,52; по содержанию жира в молоке — +0,48 и +0,57, белка — +0,66 и +0,61, соответственно. Применение современных методов оценки быков (как по качеству потомства, так и по геному) и использование ценных генотипов быков позволят повысить генетический потенциал скота. This article shows the effectiveness of using bulls evaluated by the quality of offspring and genome in the farms of the Leningrad region. On average, the increase in milk productivity in the region from the use of imported sperm of 84 bulls tested for the quality of offspring was +19 kg of milk (10138 kg of milk, 3.83% fat, 3.20% protein), 68 genomically evaluated bulls — +24 kg of milk (10568 kg of milk, 3.85% fat, 3.23% protein). The best results in assessing the quality of offspring in the farms of the Leningrad region were obtained from imported producers with a breeding value of more than +600 kg of milk (+218 kg of milk for bulls evaluated for the quality of offspring, +120 kg of milk for genomically evaluated bulls). The level of breeding value for the milk yield of the improver Davis 138027041 varies from +297 to +615 kg of milk. In highly productive (10,000 kg and higher) herds, the excess of milk yield over peers was greater than in herds with a productivity of 8000 kg of milk with a repeatability coefficient of 0.85. Bulls with a high genomic rating (from +719 kg to +1137 kg of milk) increased the milk yield of their daughters compared to their peers in the farms of the Leningrad region from +274 kg (Sterling 69701759) to +1063 kg (Saloon 70358061). With the increase in the genomic breeding value of producers, there is an increase in the productivity of daughters in the farms of the region by 1469 kg of milk. A positive relationship was found between the estimates of the breeding value of bulls by different methods (in the United States, the BLUP method, in the Leningrad region — «daughters—peers» method) for bulls tested for the quality of offspring +0.54, with a genomic score of +0.52; in terms of fat content in milk — +0.48 and +0.57, protein — +0.66 and +0.61, respectively. The use of modern methods for evaluating bulls (both by the quality of offspring and by genome) and the use of valuable genotypes of bulls will increase the genetic potential of livestock.


Author(s):  
Leontiі Khmelnychyi ◽  
Valeriia Pryimachok ◽  
Maksym Prokopovych ◽  
Serhii Kholod ◽  
Serhii Hryshyn

Researches to study the milk productivity dependence of Ukrainian Red-and-White dairy cows on genotypic and paratypic factors were conducted in the breeding farm PAE "Piskivske" Bakhmach district of Chernihiv region. The most representative five genotypic groups of animals divided by the conditional share of heredity of Holstein breed were studied: I - livestock with a share of blood 50.01-56.25; II - 56.26-62.50; III - 62.51-75.00 and IV - 75.01-87.50; V - 87.51% and <. By comparing different genotype groups of cows installed dependence of yield amount on conditional share of inheritance Holstein breed. With the growth conditional proportion of Holstein blood, milk yield increased during the evaluated first three and higher lactations. The high and reliable effect was found on the yield amount of cows firstborn by factors of birth (  = 0.329) and calving (   = 0.336). The share of birth and calving season influence on milk yield although insignificant but reliable and amounted to 3.7 and 5.3%, respectively. The value of milk yield of cows firstborn in the controlled herd greatly depended on the sire genotype (  = 0.315), cow's conditional blood by Holstein breed (  = 0.264), father breeding value (   = 0.335) and mother cow's father (  = 0.340), paternal (   = 0.163) and maternal line (   = 0.089). According to research results was substantiated expediency of monitoring selection information, identification and use of animal-specific patterns of leading traits development of milk productivity depending on the geno-  and paratypic factors influence in the selection process of pedigree herd formation.


2020 ◽  
Vol 5 (86) ◽  
pp. 73-81
Author(s):  
V.S. Buyarov ◽  
◽  
A.R. Lyashuk ◽  
◽  
◽  
...  

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.


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