Научная статья на тему 'Improvement of milk veterinary-sanitary and qualitative parameters through nutrition supplements for milking cows'

Improvement of milk veterinary-sanitary and qualitative parameters through nutrition supplements for milking cows Текст научной статьи по специальности «Животноводство и молочное дело»

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Ключевые слова
MILK QUALITY / VETERINARY-SANITARY INDICATORS / COWS / RUMEN / METABOLISM / FEED SUPPLEMENT / Качество молока / ветеринарно-санитарные показатели / коровы / рубец / метаболизм / кормовая добавка

Аннотация научной статьи по животноводству и молочному делу, автор научной работы — Yurusova A.V.

This study deals with feeding milking cows with phytogenic nutrition supplements in order to enhance their metabolic function and milk sanitary and veterinary parameters. The suggested multicomponent phytogenic nutrition supplement contains stems and lower leaves of stevia plants (Stevia rebaudiana Bertoni), yacon (Smallanthus sonchifolius) and apple pulps. Stevioside, inulin and pectin are the most valuable elements in the supplement since their combination has a complex beneficial effect on an animal organism. With its unique chemical composition, the supplement can exert anti-inflammatory, diuretic, hypoglycemic, immunomodulatory and antioxidant effects on an animal organism. The nutrition supplement regulates enzyme system, contributes to fat, protein and carbon uptake, and stimulates digestive tract and endocrine system. The analysis of microbial and physiological parameters of rumen digesta of the experimental group showed a growth of protozoa and bacteria contents, greater microbial activity and larger amount of volatile fatty acids (VFAs). The analysis of milk also revealed that feeding milking cows with this supplement stimulates growth of protein, lactose and dry matter contents and leads to rearrangement of protein fractions by increasing casein content and decreasing the amount of whey proteins. At the same time number of somatic cells, total bacterial count, number of inhibitory substances, acidity and density remain within normal limits. Milk sensory analysis also revealed no differences in consistency, color, taste and smell of milk produced by milking cows of experimental and control groups. Therefore, the suggested phytogenic nutrition supplement can bring milk veterinary, sanitary and sensory parameters in line with GOST and enhance overall milk quality. The supplement is easy to produce, has a good storage quality and pleasant flavor making it more appetizing for cattle and economically attractive for farmers.

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ОПТИМИЗАЦИЯ ВЕТЕРИНАРНО-САНИТАРНЫХ И КАЧЕСТВЕННЫХ ПОКАЗАТЕЛЕЙ МОЛОКА ПУТЕМ ВВЕДЕНИЯ В РАЦИОН ЛАКТИРУЮЩИХ КОРОВ БИОЛОГИЧЕСКИ АКТИВНОГО ФИТОСЫРЬЯ

Статья посвящена проблеме использования в рационе лактирующих коров биологически активного сырья растительного происхождения с целью улучшения обмена веществ животных и оптимизации ветеринарно-санитарных показателей молока. Предлагается использовать многокомпонентную растительную кормовую добавку, в состав которой входят: стебли и нижние листья стевии, мезга якона и яблочный жом. Стевиозид, инулин и пектин являются наиболее ценными веществами в составе добавки, а их сочетание позволяет оказывать комплексное положительное воздействие на организм животных. Химический состав всех компонентов добавки в комплексе способен оказывать противовосполительное, диуретическое, гипогликемическое, иммуномодулирующее и антиоксидантное воздействие на организм животных. Комплекс этих веществ нормализует работу ферментных систем, способствует усвоению белков, жиров и углеводов, стимулирует работу пищеварительного тракта и эндокринной системы. Лабораторные исследования микробиологических и физиологических параметров рубцового содержимого подопытных коров показали рост численности простейших, бактерий, увеличение активности рубцовой микрофлоры и количества летучих жирных кислот (ЛЖК). Анализ молока от коров опытной группы показал, что предлагаемая кормовая добавка способна стимулировать рост массовой доли белка, лактозы и доли сухого вещества, а также вызывать перераспределение фракций белка (увеличение казеина при одновременном снижением количества сывороточных белков). В тоже время количество соматических клеток, бактериальная обсемененность, ингибирующие вещества, кислотность и плотность молока остаются в пределах нормы. Органолептическая оценка молока выявила отсутствие различий в консистенции, цвете, вкусе и запахе молока животных контрольной и опытной групп. Таким образом, предлагаемая фитодобавка способна обеспечить соответствие ветеринарносанитарных и органолептических показателей качества ГОСТу наряду с улучшением технологических свойств молока. Добавка легка в приготовлении, хорошо хранится, имеет приятный вкус и запах, что делает еѐ привлекательной для поедания животными и пригодной для использования в практике кормления скота.

Текст научной работы на тему «Improvement of milk veterinary-sanitary and qualitative parameters through nutrition supplements for milking cows»

UDC / УДК 614.31:637.1:636.2.086

IMPROVEMENT OF MILK VETERINARY-SANITARY AND QUALITATIVE PARAMETERS THROUGH NUTRITION SUPPLEMENTS FOR MILKING COWS

ОПТИМИЗАЦИЯ ВЕТЕРИНАРНО-САНИТАРНЫХ И КАЧЕСТВЕННЫХ ПОКАЗАТЕЛЕЙ МОЛОКА ПУТЕМ ВВЕДЕНИЯ В РАЦИОН ЛАКТИРУЮЩИХ КОРОВ БИОЛОГИЧЕСКИ

АКТИВНОГО ФИТОСЫРЬЯ

Yurusova A.V., Post-graduate student Юрусова А. В., аспирант Voronezh State Agrarian University named after Emperor Peter the Great,

Voronezh, Russia

Воронежский государственный аграрный университет имени императора Петра I

E-mail: ny2602@yandex. ru

ABSTRACT

This study deals with feeding milking cows with phytogenic nutrition supplements in order to enhance their metabolic function and milk sanitary and veterinary parameters. The suggested multicomponent phytogenic nutrition supplement contains stems and lower leaves of stevia plants (Stevia rebaudiana Bertoni), yacon (Smallanthus sonchifolius) and apple pulps. Stevioside, inulin and pectin are the most valuable elements in the supplement since their combination has a complex beneficial effect on an animal organism. With its unique chemical composition, the supplement can exert anti-inflammatory, diuretic, hypoglycemic, immunomodulatory and antioxidant effects on an animal organism. The nutrition supplement regulates enzyme system, contributes to fat, protein and carbon uptake, and stimulates digestive tract and endocrine system. The analysis of microbial and physiological parameters of rumen digesta of the experimental group showed a growth of protozoa and bacteria contents, greater microbial activity and larger amount of volatile fatty acids (VFAs). The analysis of milk also revealed that feeding milking cows with this supplement stimulates growth of protein, lactose and dry matter contents and leads to rearrangement of protein fractions by increasing casein content and decreasing the amount of whey proteins. At the same time number of somatic cells, total bacterial count, number of inhibitory substances, acidity and density remain within normal limits. Milk sensory analysis also revealed no differences in consistency, color, taste and smell of milk produced by milking cows of experimental and control groups. Therefore, the suggested phytogenic nutrition supplement can bring milk veterinary, sanitary and sensory parameters in line with GOST and enhance overall milk quality. The supplement is easy to produce, has a good storage quality and pleasant flavor making it more appetizing for cattle and economically attractive for farmers.

АННОТАЦИЯ

Статья посвящена проблеме использования в рационе лактирующих коров биологически активного сырья растительного происхождения с целью улучшения обмена веществ животных и оптимизации ветеринарно-санитарных показателей молока. Предлагается использовать многокомпонентную растительную кормовую добавку, в состав которой входят: стебли и нижние листья стевии, мезга якона и яблочный жом. Стевиозид, инулин и пектин являются наиболее ценными веществами в составе добавки, а их сочетание позволяет оказывать комплексное положительное воздействие на организм животных. Химический состав всех компонентов добавки в комплексе способен оказывать противовосполительное, диуретическое, гипогликемическое, иммуномодулирующее и антиоксидантное воздействие на организм животных. Комплекс этих веществ нормализует работу ферментных систем, способствует усвоению белков, жиров и углеводов, стимулирует работу пищеварительного тракта и эндокринной системы. Лабораторные исследования микробиологических и физиологических параметров рубцового содержимого подопытных коров показали рост численности простейших, бактерий, увеличение

активности рубцовой микрофлоры и количества летучих жирных кислот (ЛЖК). Анализ молока от коров опытной группы показал, что предлагаемая кормовая добавка способна стимулировать рост массовой доли белка, лактозы и доли сухого вещества, а также вызывать перераспределение фракций белка (увеличение казеина при одновременном снижением количества сывороточных белков). В тоже время количество соматических клеток, бактериальная обсемененность, ингибирующие вещества, кислотность и плотность молока остаются в пределах нормы. Органолептическая оценка молока выявила отсутствие различий в консистенции, цвете, вкусе и запахе молока животных контрольной и опытной групп. Таким образом, предлагаемая фитодобавка способна обеспечить соответствие ветеринарно-санитарных и органолептических показателей качества ГОСТу наряду с улучшением технологических свойств молока. Добавка легка в приготовлении, хорошо хранится, имеет приятный вкус и запах, что делает её привлекательной для поедания животными и пригодной для использования в практике кормления скота.

KEY WORDS

Milk quality, veterinary-sanitary indicators, cows, rumen, metabolism, feed supplement. КЛЮЧЕВЫЕ СЛОВА

Качество молока, ветеринарно-санитарные показатели, коровы, рубец, метаболизм, кормовая добавка.

Production of high quality milk is one of the key development trends in agricultural sector due to several reasons, namely high competition on domestic and global markets and necessity to comply with quality and safety legal requirements. Therefore, agricultural producers have to comply with much higher standards of livestock management and improve forage quality. It means that in addition to basic fodders farmers should also feed cattle with various phytogenic nutrition supplements with a bioactive effect on a living organism and, consequently, influencing qualitative and quantitative parameters of the end product.

Phytogenic nutrition supplements are produced in the form of pomaces, cattle cakes and herbal preparations made of topinambour, rutabaga, rowan berries, tomatoes, muskmelons, watermelons, etc.

In order to enhance performance of milking cows and their milk veterinary, sanitary and qualitative parameters, we suggest feeding them with multicomponent phytogenic nutrition supplements made of agricultural byproducts that were formerly underestimated and not used as fodders. The experimental supplement consists of stems and lower leaves of stevia plants (Stevia rebaudiana Bertoni), yacon pulp (Smallanthus sonchifolius) and apple pulp.

Stevia is a valuable herb with a growing appeal for agricultural producers. One of the stevia varieties, Ramonskaya Slastena, is now cultivated in Central Russia (Voronezh Region), Leaves are of the most value since they contain diterpene glycosides that are responsible for the sweet taste of the plant. Their precursor is steviol (oxyditerpene acid) which is derived from kaurene acid. The main glycoside is stevioside in the form of white hygroscopic powder. Currently this is the only known carbon-containing (non-nitrogen) sweetener which has up to 300 times the sweetness of sugar.

Apart from the diterpene glycosides, the essential oils extracted from the leaves of stevia also attract particular interest since they contain more than 300 specific volatile compounds with only 48 of them being identified by now.

Together with diterpene glycosides and essential oils stevia contains flavonoids (quercetin, avicularin, gvalverin, quercitrin) totaling 352 mg per 100 g of air-dry leaves. The leaves of stevia are confirmed to contain cinnamic acid derivatives (caffeic and chlorogenic acid) and coumarinic acid derivatives (scopoletin and umbelliferone). Flavonoids and hydroxycinnamic acids have a wide range of biological effects. Quercitrin, avicularin and caffeic acid derivatives have several benefits, including the anti-inflammatory, choleretic, diuretic, hypoglycemic, immunomodulatory and antioxidant effects. The leaves of stevia also contain dietary minerals (phosphorus, potassium, sodium, selenium, iodine, iron, calcium,

magnesium and silicic acid) that have a beneficial effect on connective tissue, skin, hair and nails.

Chemical composition of stevia is very beneficial for a living organism - its chemical compounds regulate enzyme system, contribute to fat, protein and carbon uptake, stimulate digestive tract and endocrine system.

The second component of our experimental supplement is yacon (Smallanthus sonchifolius). The production of yacon has been growing in Russia in recent times. Yacon is a modest plant grown in various climates as it is very tolerant to a wide temperature range and different daylight hours. Yacon can be cultivated on different soils, but prefers rich, fertilizer-treated, loosened soil that allows getting high yields of juicy and brittle tuberous roots. That is why Central Russia is considered to be the most favorable area for yacon production.

Tubes are of the most value. Fresh tubes contain water, proteins and various carbons: fructose, glucose (in the form of oligofructans), sucrose and inulin as well as potassium, starch traces, various vitamins and minerals. As compared to topinambour that is more frequently used as forage, yacon tubes have a thin delicate skin with a higher content of inulin (up to 19% against 11% in topinambour on a dry basis). Besides yacon is low-caloric and therefore more attractive for agricultural producers. Furthermore, yacon has higher yields than topinambour. Aerial part of yacon, especially leaves, is also good forage for animals. Yacon stems contain 11% of protein (on a dry basis), while leaves - 17%.

According to scientific researches yacon is able to accumulate selenium which is the most important antioxidant and immunomodifier. Besides, yacon inhibits the development of putrefactive microorganisms and at the same time stimulates valuable enterobacteria, promotes synthesis of B vitamin and calcium absorption.

We chose yacon as a component for our new supplement as in addition to the above it contains inulin that is easily metabolized by animal organisms and has the flavor of apple pulp which makes forage more attractive.

The third component is apple pulp. Apple pulp is so valuable due to its composition: pectin substances, fiber, hemicellulose, protein, sugar (mainly, fructose), mineral and organic acids, ferrum, manganese, cobalt, zinc, copper, other macro- and microelements, B vitamins, an insignificant amount of fats as well as two sterol forms (phytosterols) essential for proper functioning of organisms and, eventually, influencing milk quality.

Apple pulp is especially beneficial due to the presence of pectin substances consisting of pectose (protopectin), soluble pectin and pectic (polygalacturonic) acid. Apple pulp contains 10-15% of pectin (on a dry basis), a natural purified polysaccharide extracted from apple pulp. It contributes a range of benefits, namely, enhances immune system, regulates metabolism, improves peripheral circulation and intestinal peristalsis and helps to restore mucous membranes of the respiratory and digestive tracts. The most useful property of pectin lies in its high complex formation ability, i.e. it can remove pesticides, salts of heavy metals and radionuclides from the body maintaining its bacteriological balance. Besides, apple pulp contains a large amount of quercetin antioxidant which together with vitamin C prevents an adverse effect of free radicals. Moreover, chlorogenic acid together with pectin helps to remove oxalates from the body.

There is no shortage of apple pulp in Central Russia but it is rarely used as fodder, though it is highly useful for feeding cattle due to a low amount of fiber and easily digested carbohydrates and proteins. Cattle like apple pulp, both as fresh and properly fermented fodder. When stored and transported, raw pulp quickly gets sour and loses its nutritional properties therefore we suggest using dried apple pulp for our supplement.

In combination, these three components make up a safe supplement with a beneficial bioactive effect on animals and products thereof.

First, we examined changing parameters of rumen digestion which directly depends on feeding and is one of key factors for high milk productivity of dairy cattle. This may be accounted for the fact that during the lactation period the organism works at a higher functional activity level and forestomachs are involved in a complex process, including fodder fermentation by bacteria, fungi and protozoa as well as nutrient absorption and synthesis of

new substances. This provides animals with necessary energy and nutrients. Besides, it influences physiological processes which are followed by improvement of metabolism, production and reproduction abilities. An important feature of such digestive system is an opportunity to control rumen digestion by ration adjustment because rumen digesta is specific and changes depending on fodder quality, quantity and type. In this regard, it is important and practically and theoretically relevant to examine parameters of rumen digesta.

The number of infusoria in rumen digesta represents an essential biologic criterion of a good state of the rumen flora.

The rumen digesta was analyzed based on its microbial and physiological parameters. Total number of protozoa was counted in a dilution with the help of a counting chamber under the following formula:

1. X = (a * 250 * b / 100) * 1000, where X is the infusoria count in 1 ml;

a is the infusoria count in 100 squares;

b is ruminal fluid dilution.

2. The number of microorganisms was determined under swab test method of I.P. Kondrakhin, 2004.

3. Morphological traits of protozoa were determined by microscopic examination.

4. Activity of rumen microflora was determined by measuring the time required by 20 ml of ruminal fluid to decolorize 1 ml of 0.03% methylene blue solution.

5. Volatile fatty acids were counted with the help of AAA 400 liquid chromatograph.

Table 1 - Parameters of rumen digesta during testing

Parameter Control group Ex perimental group

Basics Day 50 Day 100 Basics Day 50 Day 100

Number of protozoa, 000 / ml 289.5±2.38 291.6±2.33 290.1 ±1.14 290.4±2.16 321.0±1.99 325.8±1.23

Number of bacteria, bn / ml 7.35 ±0.78 7.37 ±0.91 7.38 ±0.82 7.35 ±0.43 8.01 ±0.26 8.05±0.33

Activity of rumen microflora, min* 4.7±0.12 4.5±0.09 4.6±0.11 4.8±0.08 3.5 ±0.03 3.6±0,05

Total VFAs, mol/l 90.5 ±1.13 88.1 ±1.21 87.0 ±1.38 90.0 ±1.14 109.9±1.05 108.6±1.25

*min - decoloration time.

The number of infusoria in the rumen digesta testified that by the 100th day protozoa had grown from 290.4 ± 2.16 to 325.8 ± 1.23 thousand per ml (10,87%) which is statistically significant. The microbial parameter of the control group changed slightly.

The experimental group also showed a microflora growth from initial contents of 7.35 ± 0.43 to 8.01 ± 0.26 billion per ml on the 50th day (8,24%) and to 8.05 ± 0.33 billion per ml on the 100th day of testing (8,7%). The rumen microbial activity also rose by 33.3% followed by quicker decoloration.

The quantitative analysis of the VFA values testified to a steady growth of the VFA level from initial contents of 90.0 ±1.14 to 109.9 ±1.05 mol/l by the 50th day (18,1%) which remained almost unchanged till the 100th day of testing.

We also carried out the quantative and qualitative analyses of milk fat because it is one of the most important milk components that constitute nutrition value, mild, nice flavor, homogenous structure and body of milk.

The supplement consisted of 1 part of stems and lower leaves of stevia plants (Stevia rebaudiana Bertoni), 2 parts of yacon pulp (Smallanthus sonchifolius) and 3 parts of apple pulp. Milking cows were fed with this supplement for 100 days in the amount of 5 g per 1 kg of live weight resulting in the increase of fat content from 3.93±0.01 % (the basic value) up to 4.06±0.01 % (the result value). The total fat content increased by 3,2%. At the same time the number of milk fat globules in milk of the experimental group rose from 3.50 up to 4.34 * 109 / ml. Thus, this parameter grew by 19.35% (P<0.001) that is statistically significant. The size of milk fat globules also increased slightly by 1.4 % (table 2).

Table 2 - Change in milk fat parameters for the experimental group

Parameters Control group Ex perimental group

Basics Day 50 Day 100 Basics Day 50 Day 100

Total fat content, % 3.93±0.03 3.9±0.05 3.93±0.03 3.93±0.02 4.0±0.03 4.06±0.02

Size of milk fat globules, micrometers 2.72±0.08 2.79±0.03 2.75±0.06 2.77±0.04 2.82±0.02 2.81 ±0.02

Number of fat globules,109/ml 3.33±0.05 3.19±0.08 3.25±0.06 3.50±0.05 3.61±0.07 4.34±0.02*

*P<0.001 - relating to basic values.

Thus, the combination of stems and leaves of stevia plants, yacon pulp and apple pulp promoted synthesis of milk fat increasing the number of milk fat globules and their size. At the same time this parameter did not change significantly in control group and remained stable.

The laboratory research revealed changes of protein quantitative and qualitative parameters in the milk of the experimental group (table 3).

Table 3 - Alteration of protein parameters in the milk of the experimental group

Parameters Control group Experimental group

Basics Day 50 Day 100 Basics Day 50 Day 100

Protein content, % 3.03±0.01 3.02 ±0.02 3.03 ±0.03 3.04 ±0.03 3.07 ±0.03 3.14 ±0.04

Casein 2.12 ±0.04 2.11 ±0.03 2.11 ±0.05 2.12 ±0.03 2.19 ±0.02 2.27 ±0.03

Whey protein 0.91 ±0.01 0.91 ±0.02 0.92 ±0.03 0.92 ±0.02 0.88 ±0.02 0.87 ±0.03

The study of the effect of experimental phytogenic nutrition supplement on quantity and quality of milk proteins revealed that feeding milking cows with this supplement results in an increase of milk proteins by 0.97 % (if fed for 50 days) and by 3.18% (if fed for 100 days). The fractional analysis of protein showed prevalence of casein contained in milk of cows fed with the experimental phytogenic nutrition supplement. Rearrangement of fractions led to an increase of the casein percentage in milk of the experimental group by 1.07 times (P<0,001). As a result the amount of whey protein decreased considerably by 5.7% (P<0.05). The control group showed no relevant changes.

Lactose is another significant component constituting the milk quality. Lactose is present in cells of every living organism and has several vital building functions - it is the main energy source and therefore contributes to regulation of specific biochemical processes, protein synthesis, neurotransmission and immunochemical processes. Figure 1 illustrates influence of alternative fodders on lactose content.

5

4,8

4,6 4,4 4,2 4

□ Control group □ Experimental group

Figure 1 - Lactose content in milk of experimental cows, %

Initial values

Final values

Taking into account that initial lactose contents in milk of experimental (4.7+0.02%) and control (4.7±0.04%) groups were similar, the further increase of lactose content in milk of cows fed with the multicomponent phytogenic nutrition supplement resulted in significant increase of dry matter in the product. By the 100th day the difference amounted to 4.45% (P<0,001): 4.72±0.05% in control group and 4.94±0.03% in experimental group.

The further study did not show any adverse impact of the nutrition supplement on sanitary and veterinary parameters of milk. The following parameters were analyzed: number of somatic cells, total bacterial count, presence of Inhibitory substances, acidity and density (Table 4).

Table 4 - Milk veterinary and sanitary parameters of experimental cattle

Parameters Control group Experimental group

Basics Day 50 Day 100 Basics Day 50 Day 100

Somatic cells, 103/cm3 329.4 ±10.3 391.4 ±13.6 378.1 ±8.66 335.1 ±5.43 354.2 ±17.1 344.9 ±18.3

Bacteria count, 103/cm3 111.2 ±23.8 204.1 ±13.5 280.3 ±18.6 110.4 ±6.23 174.7 ±11.7 159.4 ±5.11

Inhibitors - - - - - -

Acidity, °T 16.9±0.17 17.2±0.11 17.0±0.09 16.8±0.14 17.1 ±0.08 16.9±0.23

Density, °A 27.9±0.20 27.6±0.16 27.6±0.13 28.0±0.18 27.5±0.25 27.6±0.30

Apart from that, milk sensory analysis revealed no differences in consistency, color, taste and smell of milk produced by milking cows of experimental and control groups.

Based on the results, we find stevia, yacon and apple pulp supplements the most efficient for feeding milking cows. Our research gives us other evidence that alternative natural supplements have an exclusively positive effect on performance of milking cow as well as the end product. The key advantage is the contents of biologically active substances functioning as stimulants and having a protective effect.

A mixture of dried crushed stevia stems and leaves left after stevioside extraction, byproducts of inulin production from yacon and wastes of apple processing, stimulates metabolism of milking cows and improves milk veterinary, sanitary and qualitative parameters.

The supplement is advantageous for feeding highly productive milking cows as:

- the supplement is based on phytogenic ingredients without any thermal or chemical treatment;

- matching each other, the ingredients make it more appetizing for cattle due to a pleasant taste and smell;

- the supplement is easily prepared due to its bioavailable ingredients without any sophisticated equipment;

- the end mixture is easy in use and has a good storage quality;

Therefore, to improve milk veterinary, sanitary and qualitative parameters, we suggest feeding dairy cattle with multicomponent phytogenic nutrition supplement containing 1 part of dried crushed stevia stems and leaves, 2 parts of yacon pulp and 3 parts of apple pulp taken in the amount of 5 g per kg of live weight at a time.

Feeding the cows with the supplement for 100 days resulted as follows:

1. Rumen digestion was enhanced due to microbial growth (+10.87% of protozoa and +8.7% of bacteria), greater microbial activity (+33.3%) and larger amount of volatile fatty acids (VFAs) (+18.1%).

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2. Synthesis of milk components such as fat, protein, and lactose sped up by 3,2%, 3.18% and 4.45% respectively.

3. Milk fat and protein structure improved, with the number of fat globules and caseins grown by 19.35% and 6.6% respectively.

4. Milk veterinary, sanitary and sensory parameters were brought in line with TRCU 033/2013 and GOST 31449-2013.

REFERENCES

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