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11
ТРИБУНА АСПИРАНТОВ И МОЛОДЫХ УЧЕНЫХ
УДК/ UDC 636.237.21.082.263.034:636.234.1
DAIRY PRODUCTIVITY AND EFFICIENCY OF MILK PRODUCTION OF BLACK-AND-WHITE COWS OF DIFFERENT THOROUGH-BREDNESS ON THE
HOLSTEIN BREED
МОЛОЧНАЯ ПРОДУКТИВНОСТЬ И ЭФФЕКТИВНОСТЬ ПРОИЗВОДСТВА МОЛОКА ЧЕРНО-ПЕСТРЫХ КОРОВ РАЗЛИЧНОЙ КРОВНОСТИ ПО ГОЛШТИНСКОЙ ПОРОДЕ
Lyashuk A.R., Postgraduate Student Ляшук А. Р., аспирант Federal State Budgetary Educational Establishment of Higher Education "Orel State Agrarian University named after N.V. Parakhin", Orel, Russia
ФГБОУ ВО «Орловский государственный аграрный университет имени Н.В. Парахина», Орел, Россия E-mail: [email protected]
The studies were carried out from 2018 to 2019 in a pedigree reproducer for the black-and-white breed "Streletskoye" - a branch of the Federal State Budgetary Scientific Institution FSC ZBK of the Oryol Region. We realized that the number of diluted lactations in groups of cows with thorough-bredness on the Holstein breed had significant differences. According to the indications, cows with a Holstein thorough-bredness from 51 to 75% were significantly inferior to cows in the control group, which had thorough-bredness in the less than 50% Holstein breed by 36%. 76-87.5% - by 46% and cows with thorough-bredness over 87.5% - by 60%. Cows of the second, third, and fourth groups significantly exceed the indicators of the control group in terms of the average specific weight, respectively, by 17.3%, 19.4%, and 19.5%. Groups by total number, respectively, by 28.9%, 35.5%, and 52.2%. The average milk fat by lactation in the groups of black-and-white cows with Holstein thorough-bredness of 51-75%, 76-87.5%, and more than 87.5% was higher than in the control group by 16.1, 18.5 and 19.5% respectively. The proportion of Holstein breed thorough-bredness with other scientific indicators of milk productivity was in the range of 8.25-13.24% and was due to a non-existent breeding point of view. The economic efficiency of milk production of black-and-white cows has sufficient thorough-bredness for the Holstein breed. Indicators of keeping cows with Holstein thorough-bredness in the range of 51-75% are significantly inferior to cows with thorough-bredness less than 50% by 225.0 thousand rubles. Similarly, cows from groups with Holstein blood of 76-87.5% and more than 87.5% yield in the control group by 276.2 and 412.4 thousand rubles, respectively.
Key words: dairy cattle breeding, number of completed lactation, average milk yield, mass fraction of fat, mass fraction of protein, correlation between indicators of productivity, cost of milk of basic fat content.
Исследования проводились в период с 2018 по 2019 год в племенном репродукторе по черно-пестрой породе «ОС «Стрелецкое» - филиал ФГБНУ ФНЦ ЗБК Орловского района Орловской области. Установлено, что количество законченных лактаций в группах коров с различной кровностью по голштинской породе, имело существенные различия. По этому показателю коровы с кровностью по голштинской породе от 51 до 75% достоверно уступали коровам контрольной группы, имевших кровность по голштинской породе менее 50% на 36%. Еще более выраженным было отставание от контрольной группы по этому показателю коров с кровностью по голштинам 76-87,5% -на 46% и коров с кровностью более 87,5% - на 60%. Коровы второй, третьей и четвертой групп достоверно превышали показатели коров контрольной группы по среднему удою за законченную лактацию соответственно на 17,3%, 19,4% и 19,5%. Коровы второй,
третьей и четвертой групп уступали коровам первой (контрольной) группы по общему удою соответственно на 28,9%, 35,5% и 52,2%. Среднее КМЖ за лактацию в группах черно-пестрых коров с кровностью по голштинам 51-75%, 76-87,5% и более 87,5% было выше, чем в контрольной группе соответственно на 16,1, 18,5 и 19,5%. Взаимосвязь кровности по голштинской породе с остальными учтенными показателями молочной продуктивности находилась в пределах 8,25-13,24% и являлась с селекционной точки зрения несущественной. Экономическая эффективность производства молока черно-пестрых коров различной кровности по голштинской породе имела существенные отличия. По показателю стоимости молока базисной жирности за все законченные лактации коровы с кровностью по голштинам в диапазоне 51-75% достоверно уступали коровам с кровностью менее 50% на 225,0 тысяч рублей. Аналогично, коровы из групп с кровностью по голштинам 76-87,5% и более 87,5% уступали по этому показателю коровам контрольной группы соответственно на 276,2 и 412,4 тысячи рублей. Ключевые слова: молочное скотоводство, количество законченных лактаций, средний удой массовая доля жира, массовая доля белка, корреляция между признаками продуктивности, стоимость молока базисной жирности.
Introduction. Milk is one of the most important parts of the human diet. In our country, as in many other countries, mainly cow milk is used. It accounts for about 95% of the total milk consumption by the population. In 2020, the consumption of dairy products in the Russian Federation (in terms of raw milk) may reach 34.8 million tonnes. Since 2016, consumption has increased by about 1 million tonnes. This trend is expected to continue and an additional 1 million tonnes may be added over the next five years. At the same time, in terms of per capita consumption, the Russian Federation is still seriously lagging behind the countries of the European Union. Hence, the consumption of butter in the Russian Federation is 2.8 kg per person per year, cheese - 6.4 kg, while in the EU these figures are 4 kg and 20.2 kg, respectively [1].
The Oryol region, as a manufacturer of high-quality dairy products, has significant unrealized potential and many competitive advantages, which include favorable natural and climatic conditions, a good level of transport and energy infrastructure, available production capacity, and qualified personnel [2].
To realize the production potential of the dairy subcomplex in the Oryol region, it is necessary to promptly develop and implement scientifically grounded recommendations for raising the productivity of the dairy herd and improving the technology of milk production, which will allow the region to take its rightful place in the Russian dairy food market [3-5].
According to various authors, the main assets are in the field of developing the productive qualities of the livestock of Holsteinized black-and-white cows [6-9], including an increase in fat and milk protein [10, 11].
The purpose of this work was to study the milk productivity and milk production efficiency of black-and-white cows of various Holstein thorough-bredness in the Oryol region.
Materials and methods. The studies were carried out in the period from 2018 to 2019 in a pedigree reproducer for the black-and-white breed "Streletskoye" - a branch of the Federal State Budgetary Scientific Institution FSC ZBK of the Oryol District of the Oryol Region. This farm is typical for the Oryol region in terms of housing conditions, the feeding level of cows, and the technology of milk production. The rations of feeding the lactating cows on the farm were in accordance with zootechnical standards.
The object of research was the entire population of black-and-white cattle. The research material was the data of pedigree cards, zootechnical and pedigree records.
In accordance with the tasks set for this study, the experimental part of the work was a scientific and economic experiment, the scheme of which is presented below (Fig.).
Dairy productivity and efficiency of milk production of black-and-white
cows of different thorough-bredness on the Holstein breed _=□=_
Experimental groups
1 2 3 4
Holstein thorough-bredness, %
< 50 (control) 51-75 76-87,5 > 87,5
Milk productivity
Number of completed lactations Average milk yield for complete lactation Total milk yield for all completed lactations Average MFF per lactation Average AMF per lactation Total AMF for all completed lactations Average MFP per lactation Average AMP per lactation Total AMP for all completed lactations
The relationship o productivity indicators of b thorough-bredn ack-and-w ess hite cows with Holstein
Economic efficiency of milk production
Figure - Experiment scheme
Biometric processing of the results was carried out using the Microsoft Excel software. The arithmetic mean, the arithmetic mean error, the correlation (r), the criteria for the reliability of the difference between the groups (td) were calculated according to the method of G.F. Lakin [12].
Results. In accordance with the tasks set, we carried out a comparative study of milk productivity for the recorded period of productive use of cows of the studied genotypes in one of the breeding farms of the Oryol region. The following indicators were evaluated: the number of completed lactations, the average milk yield per lactation, and the total milk yield for all completed lactations (Table 1).
Table 1 - Milk productivity (per head)
№ Holstein thorough-bredness, % n, heads Number of completed lactations Average milk yield for complete lactation, kg Total milk yield for all completed lactations, kg
1 < 50 (control) 9 5,0±0,76 4860±156 24300±88
2 51-75 63 3,2±0,25*** 5700±113*** 17280±76***
3 76-87,5 209 2,7±0,12*** 5805±68*** 15674±44***
4 > 87,5 518 2,0±0,05*** 5809±45*** 11618±24***
As follows from the material presented above, the number of completed lactations in groups of cows with different thorough-bredness on the Holstein breed had significant differences. According to this indicator, cows with thorough-bredness from 51 to 75% were significantly inferior to cows of the control group, having thorough-bredness less than 50% by 36% (P<0.001). Even more pronounced was the lag behind the control group for this indicator of cows with thorough-bredness of 76-87.5% - by 46% (P<0.001) and cows with thorough-bredness of more than 87.5% - by 60% (P<0.001).
Opposite trends were found for the average milk yield per complete lactation. Thus, cows of the second, third, and fourth groups significantly exceeded the cows in
the control group by 17.3%, 19.4%, and 19.5%, respectively (P<0.001). It should be noted that no significant differences were found between groups of high-blooded Holstein cows.
The total milk yield for all completed lactations, as one of the most objective indicators of productivity, makes it possible to judge the adaptability of the animal to the conditions of feeding and breeding. Cows that are able to lactate at a high level for a long period are very valuable both breeding and economics. In our studies, the trends associated with the number of completed lactations in cows of different thorough-bredness had a certain influence on the indicators of total milk yield for all completed lactations. At the same time, the cows of the second, third and fourth groups were inferior to the cows of the first (control) group by 28.9%, 35.5%, and 52.2%, respectively (P<0.001).
The generalized conclusion, formulated according to the results of the studies presented in Table 1, is the following: in the conditions of the Oryol region in cows with an increase in thorough-bredness on the Holstein breed, there is a decrease in the number of completed lactations, as well as a decrease in the total milk yield for all completed lactations, with a simultaneous increase in the average milk yield for a lactation.
Indicators of the mass fraction of fat in the milk (MFA), the amount of milk fat (AMF) per lactation, as well as the amount of milk fat produced by a cow for the entire period of productive use, are important breeding characteristics and basic indicators for calculating the economic efficiency of milk production. The analysis of the listed parameters in the milk of black-and-white cows of various thorough-bredness for the Holstein breed is presented in Table 2.
Table 2 - The content of fat in milk of black-and-white cows of various thorough-bredness on the Holstein breed (per head)_
№ Holstein thorough-bredness, % n, heads Average MFF per lactation, % Average AMF per lactation, kg Total AMF for all completed lactations, kg
1 < 50 (control) 9 4,21±0,06 205±6,2 1023±4,1
2 51-75 63 4,23±0,03 238±4,9*** 762±3,9***
3 76-87,5 209 4,24±0,02 243±2,8*** 656±2,2***
4 > 87,5 518 4,20±0,01 245±1,8*** 490±1,5***
As follows from the data obtained, the mass fraction of fat in the milk of black-and-white cows with different Holstein thorough-bredness did not have significant differences. On the other hand, the higher milk yield, characteristic of high-blooded Holstein cows, had a decisive influence on the average amount of milk fat received from a cow per lactation.
Thus, the average AMF per lactation in the groups of black-and-white cows with Holstein thorough-bredness of 51-75%, 76-87.5%, and more than 87.5% was higher than in the control group by 16.1, 18.5 and 19.5% (P<0.001). On the other hand, a greater number of completed lactations, on average per group of cows with a Holstein thorough-bredness of up to 50%, had a decisive effect on the decrease in the total amount of milk fat for all completed lactations in groups of higher-blooded Holstein cows. In particular, in the second, third, and fourth groups of experimental cows, the lag behind the first group was 25.5%, 35.9% and 52.1% (P<0.001), respectively.
The data of studies of the protein content in milk of black-and-white cows of various thorough-bredness for the Holstein breed are presented in Table 3.
Table 3 - Protein content in milk of black-and-white cows of various Holstein thorough-
bredness (per head)
№ Holstein thorough-bredness, % n, heads Average MFP per lactation, % Average AMP per lactation, kg Total AMP for all completed lactations, kg
1 < 50 (control) 9 3,11±0,01 153,4±4,71 767±3,8
2 51-75 63 3,10±0,01 177,1±3,42*** 567±2,2***
3 76-87,5 209 3,10±0,01 179,8±2,10*** 486±1,5***
4 > 87,5 518 3,09±0,01 179,6±1,41*** 359±0,9***
As follows from the materials presented in table 3, the average mass fraction of protein in milk for lactation did not have significant differences. Variations in this indicator did not exceed 0.6%. At the same time, the average amount of milk protein per lactation in high-blooded cows (from 51 % and more) for the Holstein breed of black-and-white cows was higher than in the control group with thorough-bredness of less than 50%. Differences with the control in all cases were highly significant and amounted to 51-75% - 15.5% in the group, 17.2%, and 17.2% in the 76-87.5% group (P<0.001).
The total amount of milk protein for all completed lactations due to their different number in the groups also had highly significant differences. Cows with Holstein thorough-bredness from 51 to 75 percent were inferior to cows with thorough-bredness up to 50 percent (control) by 26.1% (P<0.001). Similarly, cows of the 3rd and 4th experimental groups lagged behind in this indicator by 36.6% and 53.2% (P<0.001), respectively.
The regularities of the relationship between the performance indicators of black-and-white cows and thorough-bredness on the Holstein breed are presented in Table 4.
Table 4 - The relationship between productivity indicators of black-and-white cows with
thorough-bredness on the Holstein breed (r, %)
Index Holstein thorough-bredness, %
Number of completed lactations, units -34,80
Average milk yield for complete lactation, kg 9,80
Total milk yield for all completed lactations, kg -29,54
Average MFF per lactation, % 9,44
Average AMF per lactation 13,24
Total AMF for all completed lactations. kg -30,33
Average MFP per lactation, % -11,72
Average AMP per lactation, kg 8,25
Total AMP for all completed lactations, kg -30,16
The calculations show that such indicators of productivity as the number of completed lactations, the total milk yield for all completed lactations, the total amount of milk fat and the total amount of milk protein obtained for all completed lactations, established in a herd of black-and-white cows, have a weak correlation with their thorough-bredness on the Holstein breed. Correlation values were in the range of 29.54-34.8%.
The proportion of thorough-bredness on the Holstein breed with the rest of the recorded indicators of milk productivity was within 8.25-13.24% and was insignificant from the breeding point of view.
The calculation of the economic efficiency of milk production of black-and-white cows of various Holstein thorough-bredness is shown in Table 5.
Table 5 - Efficiency of milk production of black-and-white cows of various Holstein
thorough-bredness (per head)
Holstein thorough-bredness, %
Index < 50 (control), n = 9 51-75, n = 63 76-87,5, n = 209 > 87,5, n = 518
Total milk yield for all completed lactations, kg 24300±88 17280±76*** 15674±44*** 11618±24***
Average MFF per lactation, % 4.21±0.06 4.23±0.03 4.24±0.02 4.20±0.01
Total milk yield of base fat contenta for all completed lactations, thousand kg 30,10±1,16 21,55±0,59*** 19,55±0,66*** 14,35±0,40***
Cost of milk with basic fat content for all completed lactationsb, thousand rubles 788,3±14,7 563,3±6,3*** 512,1±5,8*** 376,0±3,3***
Difference, thousand rubles X - 225,0 -276,2 -412,3
Notes. a Basic fat content of milk in the Oryol region - 3,4%. b The average purchase price of 1 kg of milk of basic fat content during the period of the experiment was 26.2 rubles.
As follows from the analysis of the data shown in Table 5, the economic efficiency of milk production from black-and-white cows of various Holstein thorough-bredness had significant differences. In terms of the cost of basic fat content milk for all completed lactations, cows with Holstein thorough-bredness in the range of 51-75% were significantly inferior to cows with less than 50% thorough-bredness by 225.0 thousand rubles (P<0.001). Similarly, cows from groups with Holstein thorough-bredness of 76-87.5% and more than 87.5% were inferior in this indicator to cows in the control group by 276.2 and 412.4 thousand rubles, respectively.
Conclusions. 1. The number of completed lactations in groups of cows with different Holstein thorough-bredness had significant differences. According to this indicator, cows with Holstein thorough-bredness from 51 to 75% were significantly inferior to cows of the control group, having Holstein thorough-bredness less than 50% by 36% (P<0.001). Even more pronounced was the lag behind the control group for this indicator of cows with a Holstein thorough-bredness of 76-87.5% - by 46% (P<0.001) and cows with thorough-bredness of more than 87.5% - by 60% (P<0.001).
2. Cows of the second, third and fourth groups significantly exceeded the indicators of cows in the control group in terms of average milk yield for completed lactation by 17.3%, 19.4%, and 19.5%, respectively (P<0.001). It should be noted that no significant differences were found between groups of high-blooded Holstein cows. Cows of the second, third and fourth groups were inferior to cows of the first (control) group in terms of total milk yield by 28.9%, 35.5%, and 52.2%, respectively (P<0.001).
3. The mass fraction of fat in the milk of black-and-white cows with different Holstein thorough-bredness did not have significant differences. The average AMF per lactation in the groups of black-and-white cows with a Holstein thorough-bredness of 51-75%, 76-87.5%, and more than 87.5% was higher than the control group by 16.1, 18.5 and 19,5% (P<0.001) respectively. A greater number of completed lactations, on average for a group of cows with a Holstein thorough-bredness of up to 50%, had a decisive effect on the decrease in the total amount of milk fat for all completed lactations in groups of higher-blooded Holstein cows. In particular, in the second, third, and fourth groups of experimental cows, the lag behind the first group was 25.5%, 35.9% and 52.1% (P<0.001), respectively.
4. The average mass fraction of protein in the milk of cows during lactation did not have significant differences. At the same time, the average amount of milk protein per lactation in high-blooded cows (from 51 % and more) for the Holstein breed of black-and-white cows was higher than in the control group with thorough-bredness of less than 50%. Differences with the control in all cases were highly significant and amounted to 51-75% - 15.5% in the group, 17.2%, and 17.2% in the 76-87.5% group (P<0.001). The total amount of milk protein for all completed lactations due to their different number in the groups also had highly significant differences. Cows with Holstein thorough-bredness from 51 to 75 percent were inferior to cows with thorough-bredness up to 50 percent (control) by 26.1% (P<0.001). Similarly, cows of the 3rd and 4th experimental groups lagged behind in this indicator by 36.6% and 53.2% (P<0.001), respectively.
5. The number of completed lactations, the total milk yield for all completed lactations, the total amount of milk fat, and the total amount of milk protein obtained for all completed lactations in a herd of black-and-white cows have a weak correlation with their Holstein thorough-bredness. Correlation values were in the range of 29.54-34.8%. The relationship of Holstein thorough-bredness with the rest of the recorded indicators of milk productivity was within 8.25-13.24% and was insignificant from the breeding point of view.
6. The economic efficiency of milk production from black-and-white cows of various thorough-bredness on the Holstein breed had significant differences. In terms of the cost of base fat milk for all completed lactations, cows with Holstein thorough-bredness in the range of 51-75% were significantly inferior to cows with less than 50% thorough-bredness by 225.0 thousand rubles (P<0.001). Similarly, cows from groups with Holstein thorough-bredness of 76-87.5% and more than 87.5% were inferior in this indicator to cows in the control group by 276.2 and 412.4 thousand rubles, respectively.
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