Научная статья на тему 'INFLUENCE OF THE BIRTH SEASON OF FIRST-CALF HEIFERS ON MILK PRODUCTIVITY AND MILK PRODUCTION EFFICIENCY IN THE CONDITIONS OF THE OREL REGION'

INFLUENCE OF THE BIRTH SEASON OF FIRST-CALF HEIFERS ON MILK PRODUCTIVITY AND MILK PRODUCTION EFFICIENCY IN THE CONDITIONS OF THE OREL REGION Текст научной статьи по специальности «Животноводство и молочное дело»

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Ключевые слова
МОЛОЧНОЕ СКОТОВОДСТВО / МОЛОЧНАЯ ПРОДУКТИВНОСТЬ ПЕРВОТЕЛОК / СЕЗОН РОЖДЕНИЯ ПЕРВОТЕЛОК / УДОЙ / ЖИРНОМОЛОЧНОСТЬ / БЕЛКОВОМОЛОЧНОСТЬ / ЭКОНОМИЧЕСКАЯ ЭФФЕКТИВНОСТЬ ПРОИЗВОДСТВА МОЛОКА / DAIRY CATTLE BREEDING / MILK PRODUCTIVITY OF FIRST-CALF HEIFERS / SEASON OF BIRTH OF FIRST-CALF HEIFERS / MILK YIELD / FAT-MILK CONTENT / PROTEIN-MILK CONTENT / ECONOMIC EFFICIENCY OF MILK PRODUCTION

Аннотация научной статьи по животноводству и молочному делу, автор научной работы — Lyashuk A.R.

The purpose of this study was to verify the influence of the season of birth of first-calf heifers of Holstein and Black-and-White breeds on milk productivity and economic efficiency of milk production in the Orel region. The highest milk productivity was demonstrated by Holstein heifers born in the autumn period (from September to November). In terms of the amount of milk fat and milk protein produced in 305 days of lactation, Holstein heifers of autumn exceeded their peers of spring and winter, respectively, by 6.1% (P≤0.01) and 6.6% (P≤0.001) and by 5.4 (P≤0.01) and 5.8% (P≤0.01). First-calf heifers of the black-and-white breed in the autumn months showed a positive trend in terms of milk yield in 305 days of lactation over first-calf heifers of the spring and winter months of birth - by 3.4% and 5.3%. In terms of the amount of milk fat produced in 305 days of lactation, first-calf heifers of the black-and-white breed of autumn exceeded first-calf heifers of the other seasons of birth, respectively: spring - by 6.3% (P≤0.05), summer - by 7.6% (P≤0.05) and winter - by 6.3% (P≤0.05). In terms of the amount of milk protein, first-calf heifers of the autumn birth season had a significant advantage only relating to first-calf heifers of the summer months of birth - by 7.2% (P≤0.05). The calculation showed higher economic efficiency of milk production for 305 days of lactation by first-calf heifers of the Holstein breed born in the autumn months in comparison with first-calf heifers born in the spring - by 14.5 thousand rubles, first-calf heifers born in the summer months - by 2.2 thousand rubles and first-calf heifers born in the winter - by 13.4 thousand rubles. First-calf heifers of the black-and-white breed, born in the autumn months, surpassed the baseline fat content of the first-calf heifers of the spring season of birth by 12.4 thousand rubles in value, the first-calf heifers of the summer season of birth by 14.9 thousand rubles, and the first-calf heifers of the winter season of birth by 13.0 thousand rubles.

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Текст научной работы на тему «INFLUENCE OF THE BIRTH SEASON OF FIRST-CALF HEIFERS ON MILK PRODUCTIVITY AND MILK PRODUCTION EFFICIENCY IN THE CONDITIONS OF THE OREL REGION»

UDC / УДК 636.2-055.25:636.2-053.31 "321/324":636.2.034(470.319)

INFLUENCE OF THE BIRTH SEASON OF FIRST-CALF HEIFERS ON MILK PRODUCTIVITY AND MILK PRODUCTION EFFICIENCY IN THE CONDITIONS

OF THE OREL REGION

ВЛИЯНИЕ СЕЗОНА РОЖДЕНИЯ ПЕРВОТЕЛОК НА МОЛОЧНУЮ ПРОДУКТИВНОСТЬ И ЭФФЕКТИВНОСТЬ ПРОИЗВОДСТВА МОЛОКА В УСЛОВИЯХ ОРЛОВСКОЙ ОБЛАСТИ

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 purpose of this study was to verify the influence of the season of birth of first-calf heifers of Holstein and Black-and-White breeds on milk productivity and economic efficiency of milk production in the Orel region. The highest milk productivity was demonstrated by Holstein heifers born in the autumn period (from September to November). In terms of the amount of milk fat and milk protein produced in 305 days of lactation, Holstein heifers of autumn exceeded their peers of spring and winter, respectively, by 6.1% (P<0.01) and 6.6% (P<0.001) and by 5.4 (P<0.01) and 5.8% (P<0.01). First-calf heifers of the black-and-white breed in the autumn months showed a positive trend in terms of milk yield in 305 days of lactation over first-calf heifers of the spring and winter months of birth - by 3.4% and 5.3%. In terms of the amount of milk fat produced in 305 days of lactation, first-calf heifers of the black-and-white breed of autumn exceeded first-calf heifers of the other seasons of birth, respectively: spring - by 6.3% (P<0.05), summer - by 7.6% (P<0.05) and winter - by 6.3% (P<0.05). In terms of the amount of milk protein, first-calf heifers of the autumn birth season had a significant advantage only relating to first-calf heifers of the summer months of birth - by 7.2% (P<0.05). The calculation showed higher economic efficiency of milk production for 305 days of lactation by first-calf heifers of the Holstein breed born in the autumn months in comparison with first-calf heifers born in the spring - by 14.5 thousand rubles, first-calf heifers born in the summer months - by 2.2 thousand rubles and first-calf heifers born in the winter - by 13.4 thousand rubles. First-calf heifers of the black-and-white breed, born in the autumn months, surpassed the baseline fat content of the first-calf heifers of the spring season of birth by 12.4 thousand rubles in value, the first-calf heifers of the summer season of birth by 14.9 thousand rubles, and the first-calf heifers of the winter season of birth by 13.0 thousand rubles.

Key words: dairy cattle breeding, milk productivity of first-calf heifers, season of birth of first-calf heifers, milk yield, fat-milk content, protein-milk content, economic efficiency of milk production.

Целью данного исследования было установить влияние сезона рождения первотелок голштинской и черно-пестрой пород на молочную продуктивность и экономическую эффективность производства молока в условиях Орловской области. Наибольшую молочную продуктивность продемонстрировали голштинские первотелки, родившиеся в осенний период (с сентября по ноябрь). По количеству молочного жира и молочного белка, произведенного за 305 дней лактации, голштинские первотелки осеннего сезона рождения превосходили сверстниц весенних и зимних месяцев рождения соответственно на 6,1% (Р<0,01) и 6,6% (Р<0,001) и на 5,4 (Р<0,01) и 5,8% (Р<0,01). Первотелки черно-пестрой породы осенних месяцев рождения продемонстрировали тенденцию к превосходству по показателю удоя за 305 дней лактации над первотелками весенних и зимних месяцев рождения - на 3,4% и 5,3%. По количеству молочного жира, произведенного за 305 дней лактации, первотелки черно-пестрой породы осеннего сезона рождения превосходили первотелок остальных сезонов рождения, соответственно:

весенних - на 6,3% (Р<0,05), летних - на 7,6% (Р<0,05) и зимних - на 6,3% (Р<0,05). По количеству молочного белка, первотелки осеннего сезона рождения имели достоверное превосходство только в отношении первотелок летних месяцев рождения - на 7,2% (Р<0,05). Произведенный расчет продемонстрировал более высокую экономическую эффективность производства молока за 305 дней лактации первотелками голштинской породы, родившимися в осенние месяцы в сравнении с первотелками, родившимися в весенний период - на 14,5 тыс. рублей; первотелками, родившимися в летние месяцы -на 2,2 тыс. рублей и первотелками, родившимися в зимний период - на 13,4 тыс. рублей. Первотелки черно-пестрой породы, родившиеся в осенние месяцы, превосходили по стоимости произведенного молока базисной жирности первотелок весеннего сезона рождения - на 12,4 тыс. рублей, первотелок летнего сезона рождения - на 14,9 тыс. рублей и первотелок зимнего сезона рождения - на 13,0 тыс. рублей. Ключевые слова: молочное скотоводство, молочная продуктивность первотелок, сезон рождения первотелок, удой, жирномолочность, белковомолочность, экономическая эффективность производства молока.

Introduction. According to preliminary data in 2020, milk production in the Russian Federation exceeded 32 million tonnes. Over the past five years, the share of imports on the Russian dairy market has decreased from 22% to 19%. This is almost double the limit set by the Food Security Doctrine. At the same time, from 2016 to 2020, there was a gradual increase in milk consumption to 34.8 million tons. On the other hand, according to Rosstat, the actual consumption of dairy products in Russia is still below the recommendations of the Ministry of Health [1].

The Orel region, as a manufacturer of high-quality dairy products, has several competitive advantages, which include favorable natural and climatic conditions, good transport and energy infrastructure, free production facilities, and qualified personnel [2]. To realize the listed competitive advantages, it is necessary to actualize the existing productivity potential by improving milk production technologies [3-5].

It is generally accepted that an increase in the efficiency of milk production is associated with the study of various paratypical factors that affect the growth and development of young animals, exterior features, and productivity of cows. In particular, several domestic and foreign scientists have established that cows of different seasons of birth demonstrate certain differences in milk productivity and, as a result, different indicators of economic efficiency of milk production [6-13].

These patterns, in the opinion of most researchers, are due to the unequal conditions of feeding and maintenance during the transitional periods of the year, which are the pregnancy of mothers, the rearing of experimental young animals, the organization of milk production, and other factors that determine the subsequent milk productivity.

Based on the foregoing, the purpose of this study was to ascertain the influence of the season of birth of first-calf heifers of the Holstein and black-and-white breeds on milk productivity and economic efficiency of milk production in the Orel region.

Methods and materials. The research was carried out in 2020 in the pedigree farms of the Orel region involved in breeding Holstein cows (Slavyanskoe) and black-and-white cows (Mtsenskaya).

In order to achieve the set objectives, an analysis of milk productivity and economic efficiency of milk production was carried out for 305 days of the first complete lactation of cows (first-calf heifers) born in 2007-2017, divided into four groups according to the season of birth (Figure 1).

Biometric processing of the results was carried out on a PC using Microsoft Excel. 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 [14].

INFLUENCE OF THE BIRTH SEASON OF FIRST-CALF HEIFERS ON MILK PRODUCTIVITY AND MILK PRODUCTION EFFICIENCY IN THE CONDITIONS OF THE OREL REGION

Holstein breed, n = 595 Black-and-white breed, n = 428

Ji_i

Birth season

Spring (control group) | Summer Autumn Winter

Milk productivity in 305 days of lactation

Milk yield, kg Mass fraction of fat (MFF),% The amount of milk fat (AMF), kg Protein mass fraction (PMF),% The amount of milk protein (AMP), kg

The economic efficiency of milk production

Figure 1 - Scheme of the experiment

Results. At the first stage of our studies, we examined the effect of the birth season on the indicators of milk productivity of first-calf heifers of the Holstein breed (Table 1).

Table 1 - Milk productivity of Holstein first-calf heifers in different seasons of birth, M±m

Indicator Birth season

Spring (control) Summer Autumn Winter

Head count 113 193 166 123

Milk yield, kg 7791±112 8144±113* 8305±104*** 7854±103

Mass fraction of fat,% 3.78±0.02 3.81±0.02 3.78±0.02 3.78±0.02

The amount of milk fat, kg 295±4.65 311±4.88* 313±4.21** 297±4.25

Protein mass fraction,% 3.29±0.01 3.28±0.01 3.29±0.01 3.29±0.01

The amount of milk protein, kg 256±3.64 268±3.69* 273±3.45*** 258±3.43

Note. *** - P<0.001; ** - P<0.01; * - P<0.05.

It was established that Holstein first-calf heifers of different seasons of birth, bred in the conditions of the Oryol region, are characterized by different indicators of milk productivity. Thus, the highest milk productivity was demonstrated by first Holstein heifers born in the autumn period (from September to November). Their superiority in milk yield in 305 days of lactation over first-calf heifers in spring months of birth (from March to May) was 6.6% (P<0.001). Also, first-calf heifers of autumn months of birth significantly exceeded first-calf heifers of winter months of birth (from December to February) - by 5.7% (P<0.001). In turn, first-calf heifers born in the summer period (from June to August) had higher milk productivity than their peers born in the spring months - by 4.5% (P < 0.05).

The differences concerning the milk yield of first-calf heifers in different seasons of birth influenced the differences in the indices of fat-milk and protein-milk content.

In particular, in terms of the amount of milk fat and milk protein produced in 305 days of lactation, Holstein heifers of the autumn season exceeded their peers of spring and winter, respectively, by 6.1% (P<0.01) and 6.6% (P< 0.001) and 5.4 (P<0.01) and 5.8% (P<0.01).

It is also necessary to note the significant superiority of Holstein first-calf heifers of summer over first-calf heifers of spring in terms of the amount of milk fat and milk protein, respectively, by 5.4% (P<0.05) and 3.9% (P<0.05).

The main conclusion drawn from the research results is the confirmed superiority of autumn first-calf heifers of the Holstein breed over first-calf heifers of the spring and winter seasons of birth in terms of milk yield, the amount of milk fat and milk protein obtained in 305 days of lactation. At the second stage of the work, we conducted a study of the influence of the season of birth on the indicators of milk productivity of first-calf heifers of the black-and-white breed (Table 2).

Table 2 - Milk productivity of first-calf heifers of the black-and-white breed in different seasons of birth, M±m_

Indicator Birth season

Spring (control) Summer Autumn Winter

Head count 129 108 82 108

Milk yield, kg 7269±144 7040±150 7516±169 7140±153

Mass fraction of fat,% 3.70±0.02 3.76±0.02 3.79±0.02** 3.75±0.02

The amount of milk fat, kg 268±5.22 265±6.05 285±6.44* 268±5.94

Protein mass fraction,% 3.15±0.01 3.16±0.01 3.16±0.01 3.17±0.01

The amount of milk protein, kg 229±4.51 222±4.79 238±5.35 226±4.95

Note. ** - P<0.01; * - P<0.05.

The exhibited differences concerning milk productivity in first-calf heifers of the Holstein breed of different seasons of birth, in general, were confirmed in relation to first-calf heifers of the black-and-white breed, bred in the Orel region.

In particular, first-calf heifers of the black-and-white breed of autumn showed a more favorable trend in terms of milk yield in 305 days of lactation over first-calf heifers of the spring and winter months of birth - by 3.4% and 5.3%. Along with this, a significant advantage in milk yield of first-calf heifers of the autumn season of birth over first-calf heifers of the summer season of birth was ascertained - by 6.8% (P<0.05).

The differences in the amount of milk fat and milk protein established between first-calf heifers of the black-and-white breed of different seasons of birth, in general, were also similar to the patterns established for the first-calf heifers of the Holstein breed. So, in terms of the amount of milk fat produced in 305 days of lactation, first-calf heifers of the black-and-white breed of the autumn season of birth exceeded the first-calf heifers of the other seasons of birth, respectively: spring - by 6.3% (P<0.05), summer - by 7.6 % (P<0.05) and winter - by 6.3% (P<0.05).

On the other hand, in terms of the amount of milk protein, first-calf heifers of the autumn birth season had a significant superiority only concerning first-calf heifers of the summer months of birth - by 7.2% (P<0.05).

Noteworthy is the established superiority of black-and-white first-calf heifers of the autumn season of birth over the first-calf heifers of the spring season of birth in terms of the mass fraction of fat in milk - by 2.4% (P<0.01).

In general, the tendency for the superiority of first-calf heifers of the black-and-white breed, autumn season of birth, over first-calf heifers born in spring, summer and winter seasons can be considered established.

For clarity, the milk yield for 305 days of lactation of first-calf heifers from different seasons of birth in terms of baseline fat content are presented in the form of graphs in Figure 2.

9500 9250 9000 8750 8500 8250 8000 7750 7500

Figure 2 - Milk productivity in terms of baseline fat content of first-calf heifers of

different seasons of birth

Spring

Summer ■Holstein breed

Autumn Winter

■Black-and-white breed

The graphs presented in Figure 2 demonstrate largely similar patterns of milk productivity for groups of first-calf heifers of Holstein and Black-and-White breeds of different seasons of birth.

Moreover, calculations were made of the economic efficiency of milk production by first-calf heifers of Holstein and black-and-White breeds of different birth seasons, bred in the conditions of the Oryol region (Table 3).

Table 3 - Economic efficiency of milk production by first-calf heifers in different seasons of birth (per head), M±m_

Indicator Birth season

Spring (control) Summer Autumn Winter

Holstein breed

Head count 113 193 166 123

Milk yield of baseline fatness *, kg 8679 9151 9233 8721

Cost of produced milk with baseline fatness, thousand rubles ** 227.4 239.7 241.9 228.5

Black-and-white breed

Head count 129 108 82 108

Milk yield of baseline fatness *, kg 7894 7797 8366 7869

Cost of produced milk with baseline fatness, thousand rubles ** 206.8 204.3 219.2 206.2

* Baseline fat content of milk in the Orel region - 3,4%.

** The average purchase price of 1 kg of milk of baseline fat content during the experiment was 26.2 rubles.

The calculation showed higher economic efficiency of milk production for 305 days of lactation by first-calf heifers of the Holstein breed born in the autumn months in comparison with first-calf heifers born in the spring - by 14.5 thousand rubles, first-calf heifers born in the summer months - by 2.2 thousand rubles and first-calf heifers born in the winter - by 13.4 thousand rubles.

Similarly, first-calf heifers of the black-and-white breed, born in the autumn months, exceeded the cost of milk production of the baseline fat content of the first-calf heifers of spring by 12.4 thousand rubles, the first-calf heifers of summer - by 14.9 thousand rubles, and the first-calf heifers of winter - by 13.0 thousand rubles.

Thus, the most effective heifers in relation to the cost of milk produced with baseline fat content were first-calf heifers of the autumn birth season, both Holstein and black-and-white breeds.

Conclusions. Based on the studies carried out, we formulated the following conclusions:

1. The highest milk productivity was demonstrated by Holstein heifers born in the autumn period (from September to November). Their advantage in milk yield in 305 days of lactation over first-calf heifers of spring (from March to May) was 6.6% (P<0.001). First-calf heifers of autumn significantly exceeded first-calf heifers of winter (from December to February) - by 5.7% (P<0.001). In turn, first-calf heifers born in the summer period (from June to August) had higher milk productivity than their peers born in the spring months - by 4.5% (P < 0.05).

2. In terms of the amount of milk fat and milk protein produced in 305 days of lactation, Holstein first-calf heifers of autumn exceeded their peers of the spring and winter, respectively, by 6.1% (P<0.01) and 6.6% (P<0.001 ) and by 5.4 (P<0.01) and 5.8% (P<0.01). A significant superiority of Holstein heifers of summer over first-calf heifers of spring in terms of the amount of milk fat and milk protein was established, by 5.4% (P<0.05) and 3.9% (P<0.05), respectively.

3. First-calf heifers of the black-and-white breed of autumn months of birth showed a tendency to superiority in terms of milk yield in 305 days of lactation over first-calf heifers of spring and winter months - by 3.4% and 5.3%. Along with this, a significant superiority in milk yield of first-calf heifers of autumn over first-calf heifers of summer was established - by 6.8% (P<0.05).

4. In terms of the amount of milk fat produced in 305 days of lactation, first-calf heifers of the black-and-white breed of the autumn season exceeded the first-calf heifers of the other seasons, respectively: spring - by 6.3% (P<0.05), summer - by 7.6% (P<0.05) and winter - by 6.3% (P<0.05). In terms of the amount of milk protein, first-calf heifers of the autumn birth season had a significant superiority only in relation to first-calf heifers of summer - by 7.2% (P<0.05).

5. The calculation showed higher economic efficiency of milk production for 305 days of lactation by first-calf heifers of the Holstein breed, born in the autumn months in comparison with first-calf heifers born in the spring - by 14.5 thousand rubles, by first-calf heifers born in the summer months - by 2.2 thousand rubles and first-calf heifers born in the winter - by 13.4 thousand rubles.

6. First-calf heifers of the black-and-white breed, born in the autumn months, surpassed the baseline fat content of the first-calf heifers of the spring season by 12.4 thousand rubles in value, the first-calf heifers of summer - by 14.9 thousand rubles and first-calf heifers of winter - by 13.0 thousand rubles.

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