scholarly journals Evaluation of Bulls and Related Groups of the Jersey Breed on Dairy Productivity and Reproductive Capacity of Offspring

2021 ◽  
Vol 24 (5) ◽  
pp. 54-68
Author(s):  
Yurii Polupan ◽  
Dmytro Kucher ◽  
Oleksandr Kochuk-Yashchenko ◽  
Olga Biriukova
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Statistical Significance ◽  
Reproductive Capacity ◽  
Milk Productivity ◽  
Paternal Origin ◽  
Capacity Coefficient ◽  
Service Period ◽  
Related Group ◽  
Jersey Cows

The article presents the results of research on the influence of paternal origin and belonging to a related group on the level of milk productivity of cows and the reproductive capacity of Jersey cows in the farm “Dan-Milk” of the Zhytomyr Region. The purpose of this study is to establish the influence of paternal origin and belonging to a related group on the level of milk productivity and reproductive capacity parameters of Jersey cows. The study established a substantial level of differentiation in the main economically useful features between groups of half-sisters by father. The best quantitative indicators of milk productivity were noted among the daughters of bulls DJ Jante 302761 (P<0.001) and Headline 114114336 (P<0.001), the worst indicators – among daughters of Karl 67037285. The highest indicators of fat and protein content in milk were noted in the cows bred from the bull Legal 61929249, the lowest – from the bull Karl 67037285. The influence of the origin of cows by father on the variability of milk yield and yield of milk fat and protein was 20.3–30.3% (up to P<0.001), the content of fat and protein in milk decreased to 13.2-20.0% (P<0.01 and P<0.05), and according to the reproductive capacity features – to 7.8-19.0% with an unreliable level of statistical significance. Prepotent as to milk yield are bulls Legal 61929249 and Headline 114114336, as to the content and yield of milk protein – Legal 61929249. Cows of the related group bred from the bull Observer 553236 are characterised by the highest milk yield and yield of milk fat and protein for both the first and best lactation, and cows of the related group bred from Surville 604694 are characterised by the worst yield. The influence of belonging to a related group on the studied features was several times lower (0.2-10.5%) compared to the influence of paternal origin. With an increase in the milk yield of cows over the first lactation, there is a stable and substantial decrease in the reproductive capacity coefficient due to the lengthening of the service period between the first and second calving. Such natural antagonism does not imply the goal of increasing the duration of the service period to obtain maximum milk yields for firstborn cows, since this will lead to a decrease in the yield of calves and render timely replenishment of the herd impossible. It is optimal to milk the firstborn up to 8 tonnes over 305 days of lactation while maintaining a satisfactory reproductive level

scholarly journals THE ASSESSMENT OF THE ADAPTABILITY OF JERSEY BREED COWS

2020 ◽  
Vol 60 ◽  
pp. 61-70
Author(s):  
N. Pelekhaty ◽  
D. Kucher ◽  
O. Kochuk-Yashchenko ◽  
A. Lypianets
Keyword(s):  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Reproductive Capacity ◽  
Milk Productivity ◽  
Significant Deterioration ◽  
Reproductive Ability ◽  
Service Period ◽  
Jersey Cows ◽  
Adaptation Index

The results of the studies carried out highlight the assessment of the adaptive ability of Jersey cows. The conditions of keeping Jersey cows in the Dan Milk subsidiary contribute to the realization of high milk productivity, which is due to heredity, but cause a deterioration in their reproductive capacity. At the same time, a high manifestation of milk productivity and satisfactory reproductive ability have observed only in the daughters of DJ Jante 302761 – whose adaptation index was closer to zero and amounted to -2.7. The force of influence (ηx2) of paternal origin on the signs of milk production in first-calf calfs was 21.1% versus 5.9% of the generalized mean value for cows belonging to the line. It has been founded that according to the adaptation index, the state of animals those characterized by the absence of harmonious interaction with the environment – cows show high productivity with a significant deterioration in reproductive capacity, which indicates the presence of a feedback between these characteristics. It was found not high enough, but statistically significant influence (P < 0.01 – P < 0.001) on the adaptation level of first-calf cows by milk yield for 305 days of lactation (8.0%), milk fat and protein (7.0%). A statistically significant effect (ηx2 = 82%) of the signs of reproductive ability of cows (service period and period between calving) was found depending on their level of adaptation (P < 0.001). With an increase in the level of milk production of cows, was established a clear connection between the deterioration of the adaptive qualities of livestock. So with an increase in milk yield for the entire lactation from 6000 to 10000 kg of milk, the adaptation index decreases from -0.5 to -9.5, which is confirmed by a statistically significant difference between the extreme groups of animals with different levels of productivity (P < 0.001). According to the adaptation index, the condition of animals were characterize by the lack of harmonious interaction with the environment - cows show high milk productivity with a significant deterioration in reproductive capacity, which indicates the inverse relationship between these traits. The influence of the father and belonging to the lines on such indicators of milk productivity as: yield for 305 days of lactation, milk fat and protein (P < 0.05 – P < 0.001) was statistically significant. Significant effect of increasing the level of milk yield of cows was observed on such signs of reproductive capacity as: service period, period between calves and reproductive ability coefficient (P < 0,001). There was no statistically significant effect of belonging to the lines and offspring of specific breeders on the signs of reproduction of cows in general (P > 0.05). We found that the reproductive quality of cows is more influenced by the level of milk yield of cows during lactation (23.1%, at P < 0.001), which is confirmed by our previous studies. The conditions of keeping Jersey cows in the Dan Milk State Enterprise contribute to the realization of high milk productivity, which is due to heredity, but causes a deterioration in their reproductive capacity.

scholarly journals The impact of reproductive capacity indicators of simmental cattle on their milk productivity

2017 ◽  
Vol 19 (74) ◽  
pp. 52-56
Author(s):  
V. V. Fedorovych
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Correlation Coefficients ◽  
Reproductive Capacity ◽  
Optimal Parameters ◽  
Milk Productivity ◽  
Service Period ◽  
Simmental Cattle ◽  
The Impact

It is well known with an increase of milk productivity of cows their reproductive capacity in general became worse. Therefore, it is important to establish optimal parameters of the first age insemination and first calving, duration of service- and inter-calving periods. In view of the above, the purpose of our researches was to study the influence of reproductive capacity parameters of Simmental cows on the formation of milk productivity. The study were conducted on 331 cows in agricultural LLC «Litynskyy» Drohobych raion, Lviv oblast. Evaluation of milk productivity and reproductive capacity of the animals (in 20 years) were performed according to the data of zootechnical accounting for the first, second, third and the best lactations. The differences in rates of milk productivity depending on the parameters of their reproductive capacity were established. Animals with age of first fruitful insemination 18.1–20.0, with first calving age – 27.1–29.0, duration of service period – 101–120 and duration of the inter-calving period – 381–400 days had the best yields and the highest quantity of milk fat. According to the above mentioned indicators of milk productivity they are likely dominated by animals with bigger or smaller indicators of reproductive capacity, but in most cases, this advantage was unreliable. It was found positive highly significant links between indicators of reproductive capacity of cows and milk yield. The highest correlation coefficients were observed between age of first calving and their milk yields, depending on lactation, they were 0.380–0.498, lower – between age of first insemination and milk yield – 0.316–0.456 and the lowest – between service- and inter-calving periods and yield – 0.124–0.335; 0.127–0.331 respectively. The impact of the abovementioned indicators on yield was within 23.13–39.88; 28.63–45.02; 30.98–35.17%, respectively. 

scholarly journals Reppoductive ability of ukrainian black and white dairy cows

2016 ◽  
Vol 18 (2) ◽  
Author(s):  
M. I. Kuziv ◽  
E. I. Fedorovych
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Reproductive Capacity ◽  
Dry Period ◽  
Black And White ◽  
Reproductive Ability ◽  
Service Period ◽  
Lactation Duration ◽  
The Impact ◽  
Period Duration

The major components of economically useful traits in cattle dairy productivity, which conducted the selection is milk productivity and reproductive ability of cows. Studies conducted on animals Ukrainian black and white dairy cattle in the «Milk River» farm in the Sokal and Brody offices breeding reproducers «Breeder» Lviv region and plant breeding «Yamnytsya» Ivano–Frankivsk region. Ukrainian black and white dairy breed in the western region of Ukraine is characterized by good reproductive ability. Depending on the husbandry and lactation duration, service period lasted within 87.4 – 121.5 day, intercalving period – within 364 – 402.6 day, dry period within – 47.3 – 72.9 day, the fertility index was 46.3 – 48.0, coefficient of reproductive ability – within 0.92–0.99,  output of calves per 100 cows – within 91.8 – 98.8. The duration of pregnancy in cows of different  farms and lactations were in range 277 – 283.5 day and meet the requirements of the physiological norm. It has been shown that the milk yield of cows depends on the parameters of reproductive capacity. The correlation between duration of service–period and intercalving period, and milk yield, milk fat in most cases was positive. Correlation dry period duration and parameters of milk yield changed from negative to positive. Depending on the husbandry, lactation and index the impact share of service–period duration on milk yield was 7.0 – 29.7, for intercalving period – 8.8 – 31.8, for dry period – 9.2 – 23.8% respectively.

scholarly journals Reproductive qualities of dairy cows at different levels of milk yield

2021 ◽  
Vol 22 (4) ◽  
pp. 589-596
Author(s):  
Svetlana V. Titova
Keyword(s):  
Milk Yield ◽  
Correlation Coefficients ◽  
Comparison Method ◽  
Reproductive Capacity ◽  
Calving Interval ◽  
Milk Productivity ◽  
Reproductive Ability ◽  
Service Period ◽  
The Impact ◽  
Different Levels

The article presents the results of the analysis of the reproductive ability of cows depending on the level of their milk productivity. The studies were conducted in the Republic of Mari El on cows of the Holstein black-and-white breed (n = 3828). There have been studied the influence of different levels of milk yield on the duration of the service period and period between calvings, the output of calves per 100 cows, the coefficient of reproductive ability. The studies used the comparison method, correlation, regression and one-factor analysis of variance. It has been established that the milk yield increases with the age of cows, but at the same time the duration of the service period and calving interval increases. In first-calf cows, the service period was 128.8 days (Cv = 75.1 %), the calving interval was 403.6 days (Cv = 23.5 %). By the third lactation, with an increase in milk yield by 1030 kg (15.4 %), the duration of the service period increased by 7.2 days (5.6 %), the calving interval  -by 12.3 days (3.0 %). The share of the impact (ƞ2x) of milk yield on the duration of the service period was 5.4 %, the calving interval -4.7 %. The correlation coefficients between milk yield for 305 days of the first lactation and the duration of the service period and calving interval were 0.24 and 0.22 (p<0.05), with milk yield for the entire lactation 0.81 (p<0.05). The optimal indicators of the service period (89.4 days), the calving interval (369.4 days), the reproductive capacity (0.94) and the output of calves (1.0) were possessed by the first heifers with low milk productivity-milk yield less than 5000 kg of milk. In animals with the milk yield of 6000-9000 kg of milk or more, the duration of the service period was 12.4-249.6 % higher, the calving interval -by 1.9-32.5 % (p<0.05). According to the regression coefficients, on average, each increase in milk yield per 1000 kg increased the duration of the service period by 25.9 days, the calving interval -by 23.1 days, which worsened the output of calves by 0.24 %, and the coefficient of reproductive ability decreased by 16.0 %.

scholarly journals Reproductive qualities and milk productivity of black-and-white cows depending on sire lineage

2020 ◽  
Vol 50 (5) ◽  
pp. 47-55
Author(s):  
S. L. Belozertseva ◽  
L. L. Petrukhina
Keyword(s):  
Milk Yield ◽  
Research Work ◽  
Live Weight ◽  
Reproductive Capacity ◽  
Calving Interval ◽  
Milk Productivity ◽  
Black And White ◽  
Service Period ◽  
Significant Difference

The paper presents the results of studying the effect of sire lineage on reproductive qualities and milk yield of cows. The study was carried out inIrkutskregion on a herd of Holsteinized black-andwhite cattle of Pribaikalsky type. The analysis of the main characteristics of reproductive capacity of herd cows on a farm was performed during 2013–2018. The material of the research work was based on the informational database of animals from the program of breeding register Selex. Cows were divided according to sire lineage and milk productivity into five groups by the level of milk yield: from 5000 to6500 kg, 6501-8000, 8001-9500, 9501-11000 and more than11001 kg. Successful insemination of heifers took place at the age of 15.7-16.6 months with the live weight of more than400 kg, which corresponds to zootechnical standards. The earliest (15.7 months) insemination was in heifers of Reflection Sovereign sire line, the age of first calving was 753 days with the live weight of561 kg. The latest (498 days) successful insemination was observed in heifers of Montvik Chieftain bull line with the live weight of498 kg. Cows of Sealing Trygen Rocket (8766 kg) and Reflection Sovereign (8704 kg) sire lines had the highest milk productivity with a significant difference (p ≥ 0.90). The cows of these lines had the longest service period (164 and 179 days), as well as the length of the calving interval (445 and 458 days), respectively. The coefficient of reproductive capacity of cows of different sire lines ranged from 0.80 to 0.88, which is a low indicator.

scholarly journals Результати використання бугаїв-плідників голштинської породи при створенні високопродуктивного стада

2019 ◽  
pp. 169-180
Author(s):  
Т. В. Підпала ◽  
Є. М. Зайцев ◽  
А. О. Правда
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Milk Fat ◽  
Milk Composition ◽  
Reproductive Capacity ◽  
Practical Significance ◽  
Positive Correlation ◽  
Holstein Breed ◽  
Service Period ◽  
High Level

Мета статті – оцінити прояв господарсько корисних ознак у корів-дочок різних бугаїв-плідників голштинської породи. Методика дослідження. У процесі дослідження використані загальноприйняті зоотехнічні методи (індивідуальний облік молочної продуктивності, відтворювальної здатності), лабораторні (визначення якісного складу молока), ретроспективний аналіз (показники за весь період використання тварин), варіаційно-статистичний метод (визначення параметрів ознак). Результати дослідження. У результаті вивчення використання бугаїв-плідників голштинської породи при створенні високопродуктивного стада молочної худоби з’ясовано, що на рівень розвитку продуктивних, відтворювальних і адаптивних властивостей корів-дочок впливає походження за батьком. Встановлено взаємозв’язок між господарсько корисними ознаками корів первісток голштинської породи німецької та української селекції, які походять від різних бугаїв. Незалежно від походження піддослідних тварин зберігається позитивна високого ступеня кореляція між надоєм і кількістю молочного жиру та білка. Загальною закономірністю для потомства бугаїв голштинської породи є наявність позитивної кореляції низького, середнього і високого ступенів між надоєм і тривалістю сервіс-періоду. Визначено відмінності за напрямом і ступенем кореляційної залежності між продуктивними і відтворювальними ознаками у корів-первісток, які й характеризують різноманітність впливу бугаїв на їхніх дочок. Елементи наукової новизни. Набули подальшого розвитку теоретичні та практичні положення щодо підвищення продуктивності тварин та створення високопродуктивних стад молочної худоби за використання генофонду голштинської породи. Практична значущість. Одержані результати потрібно враховувати у процесі поліпшуючої селекції під час формування високопродуктивного стада молочної худоби голштинської породи. The purpose of the article is to evaluate the manifestation of economically useful signs of cow-daughters of Holstein breed different servicing bulls. Methods of the research. In the course of the study, commonly used zoo-technical methods (individual accounting of milk productivity, reproductive capacity), laboratory (determining the qualitative milk composition), retrospective analysis (indicators for the entire period of using animals), variation-statistical method (determining sign parameters) were used. The research results. As a result of using bulls for service of Holstein breed in creating a highly productive herd of dairy cattle it has been established that the level of developing productive, reproductive and adaptive properties of cow-daughters is influenced by the origin of the father-parent.  The correlation has been established between economically useful signs of cows-firstlings of the Holstein breed of German and Ukrainian selection from various bulls. Regardless of the experimental animals’ origin, there is a high-level positive correlation between the milk yield and the amount of milk fat and protein. The common peculiarity for the offspring of the Holstein breed is the presence of a positive correlation of the low, middle and high levels between the milk yield and the duration of the service period. The differences as to the direction and the degree of correlation dependence between productive and reproductive features of cows-firstlings have been determined, which characterize the diversity of bulls’ influence on their daughters. The elements of scientific novelty. The theoretical and practical propositions for raising the productivity of animals and creating highly productive herds of dairy cattle by using the gene pool of Holstein breed have been further developed. Practical significance. The obtained results should be taken into account in the process of improving the selection during the formation of a highly productive herd of the Holstein breed dairy cattle.

scholarly journals Relationship between reproductive capacity and productive longevity of cow

2021 ◽  
pp. 167-174
Author(s):  
L. V. Kholodova
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Economic Benefit ◽  
Extended Period ◽  
Reproductive Capacity ◽  
Milk Productivity ◽  
Age At First Calving ◽  
Research Results ◽  
Productive Life ◽  
Economic Use

One of the most critical tasks of modern dairy farming is to extend the time of productive use of cows. Studies have shown that the studied herd’s economic benefit ranged from 1005 to 3693 days and averaged 1864. The lifetime milk yield of the cows averaged 20746 kg and lifetime milk fat was 735.4 kg. On the first day of economic use, 10.2 kg of milk was obtained, and on the first day of lactation, the figure was significantly higher at 20.8 kg. The most extended use period for a cow was found to be 1903 days. The average open days were 91-120 days. The highest lifetime productivity was obtained from this group of animals, which was 21909 kg of milk. A further reduction or increase in the length of open days was accompanied by a decrease in economic use and a decrease in the productive life of the cows. When open days were too long (more than 120 days), the productive life of the cows was reduced to 1875 days, and milk productivity was also reduced to 20562 kg of milk. According to the research results, the abundant lifetime life of cows increases with the duration of inter calving period from 11 to 13 months from 14939 to 26582 kg. It was found that productive life milk yield and milk fat decreased with a more extended period between calvings. The age of the first calving had no significant effect on the duration of economic use of the cows. Individuals with first calving at 30 months of age and more excellent than 1993.2 days were best on this trait. However, the highest productive life was shown by animals whose age at first calving was 26-27, 9 months.

The relationship between milk productivity and reproduction in cows in highly productive Ayrshire herds

2021 ◽  
pp. 40-45
Author(s):  
A. Bolgov ◽  
S. Shterkel ◽  
N. Grishina
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Animal Health ◽  
Correlation Coefficients ◽  
Operating Conditions ◽  
Milk Productivity ◽  
Reproductive Ability ◽  
Service Period ◽  
Short Period ◽  
The Relationship

The purpose of the study is to study the relationship between the rates of dairy productivity and reproduction of cows in the highly productive Ayrshire herds of the Republic of Karelia.Materials and methods. The work was performed on the basis of the four Stud of the Airshire rock at the "Megrega" trivial, "Ilyinskoe", Mayak LLC, Agrocomplex OJSC. V. M. Zaitseva "(Republic of Karelia). Data on dairy productivity and reproductive ability are collected and processed in 24,720 cows. Materials of zootechnical accounting and bonitations for 2004-2020 were used. At the end of the observation period, the productivity of the Stud was 7500-8500 kg of milk.From indicators of the productivity of cows, the amount of fishing, fat products for full lactation and 305 days of lactation, from the reproduction indicators - the duration of the service period, a dry period, an interstitial period (MOP), the age of the first calf, the age of cows during the selection, the causes of the selection are taken.The main biometric constants (X ̅, ϭ, CV) were calculated, the grouping method was used to characterize the signs of signs calculated the correlation coefficients.Results. The relationship between milk productivity and reproduction was studied in 4 Ayrshire herds of 24,720 cows with an average productivity of 7500-8500 kg of milk. A high positive relationship of milk yield and milk fat production with the duration of the service period (SP) was established, the correlation coefficient was up to 0.929 (P<0.001), which is consistent with the data of other researchers of this problem. It is shown that in herds with a milk yield of 8500-9000 kg of milk, the SP duration of 135-140 days is justified. It was noted that the decrease in the age of the first calving of cows led to an increase in the milk yield of the entire herd (r =-0.676; -0.686; P<0.05).A relatively short period of use of cows in herds was recorded – 3.5-3.7 lactations, while the milk yield of cows aged six lactations and older significantly exceeded the average milk yield for the herd. This leads to a positive correlation of the period of use of cows (r =0.935; P<0.001) and the proportion of cows with six lactation and older (r =0.788; P<0.05) with the milk yield of the herd. Cows with six lactations and older can stay in the herd, provided that their performance exceeds the average level of the herd. The influence of milk yield on the length of the service period and the MOP is manifested not only within one lactation, but also in adjacent lactation. It was found that with an increase in milk yield from less than 6000 kg of milk to 9500-10000 kg or more in the previous lactation, the duration of SP in the subsequent lactation increased from 112 to 170 days, MOP – from 391 to 436 (correlation coefficients from 0.138 (P<0.01) to 0.870 (P<0.001).Conclusion. The results obtained indicate the need to develop operating conditions for cows that provide a combination of high and record milk yield with normal reproductive abilities. In particular, to ensure maximum optimization of feeding conditions, maintenance, breeding and veterinary services, and control of animal health.

scholarly journals QUALITY OF MILK PRODUCTION OF THE HOLSTEIN COWS DEPENDING ON DIFFERENT FACTORS

2020 ◽  
pp. 155-159
Author(s):  
Murodulla Eshonqulovich Ashirov ◽  
Khusniddin Abdiolimovich Donaev ◽  
Alo Askarovich Yuldashev
Keyword(s):  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Live Weight ◽  
Fat Content ◽  
Holstein Cows ◽  
Milk Productivity ◽  
Group I ◽  
Service Period ◽  
Local Selection

Studies have revealed that despite the selection, the Holstein cows have a high genetic potential of milk production and in all lactations it is good in the specific conditions of the hot climate of Uzbekistan. The milk production level of German cows for the first lactation was 6511.2 kg of milk with a fat content of 3.84%, the Dutch — 6653.0 kg with fat content of 3.95%, and local breed — 6495.2 kg with a fat content of 3.95%. All mature cows retained high milk production, for III lactation and older it was 7112.5 kg and 3.90%, 7266.0 kg and 3.90%, 6847.5 kg and 3.94%, respectively. The yield of Dutch breeding cows was higher for 1 lactation by 141.80–157.8 kg, for III lactation and older by 153.5–418.5 kg, the yield of milk fat by 12.8–6.3 kg, respectively, of indicators peers of German and local selection. The cows of the studied selections combined well with high milk yield and fat content. The level of 4% milk for the studied lactation in all cows was quite high and testified to its good nutritional value. Holstein cows of different breeds are distinguished by a strong dairy type. For I lactation, for every 100 kg of live weight, 1,159.0–1265.5 kg of milk was produced, for III lactation and older - 1200.0–1308.6 kg. It is revealed that milk productivity depends on the level of live weight of cows. The increase in body weight of cows in all groups provides an increase in milk yield, milk fat yield, milk yield of 4% milk. Milk productivity is interrelated with the duration of the service period. In group I, cows with a service period of 91–100 days were more productive, in group II, 81–90 and in group III, up to 80 days. The use of Holstein cows for the production of milk is effective and ensures an increase in its production, the creation of highly productive dairy herds and the production of high-quality maintenance stock. KEYWORDS: Holstein breed, herd, milk yield, milk, fat, selection.

scholarly journals THE INFLUENCE OF REPRODUCTIVE QUALITIES ON DAIRY PRODUCTIVITY OF COWS OF THE SIMMENTAL BREED

2021 ◽  
Vol 250 ◽  
pp. 178-184
Author(s):  
M.A. Grinchuk ◽  
◽  
Yu.A. Nesterova ◽  
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Mass Fraction ◽  
Dry Period ◽  
Milk Productivity ◽  
Yield Increase ◽  
Service Period ◽  
Kaliningrad Region ◽  
Positive Effect ◽  
Period Duration

The applicability of the work is to identify the possibility of productivity increase of cows of the Simmental breed due to reproductive qualities. The aim of the work is to assess the influence of the first insemination age, service period and dry period on milk productivity of Simmental cows. The research is aimed at studying milk productivity of Simmental cows with different levels of reproductive qualities. The obtained data were statistically processed in Excel. Descriptive statistics methods were used. The object of the research were Simmental cows of “ Tasaliev D.M. “ farm of Kaliningrad region. As a result of the study, a relation was established between the age of the first successful insemination, the service period duration, the dry period duration and parameters of milk productivity. The age of the first successful insemination at 18-24 months has the most beneficial effect on subsequent milk productivity. A service period of 90-120 days has a positive effect on milk yield increase for 305 days of lactation, a longer service period negatively affects the mass fraction of milk fat. Prolonged service period results in a calf loss of 100 calves per year. With an increase of dry period duration, the mass fraction of milk fat increases, but milk yield decreases. The influence of reproductive qualities on mass fraction of milk protein is insignificant. According to the results of the studies, it can be considered that reproductive qualities, in combination with other factors, influence milk productivity of Simmental cows.

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