Mass Fraction Of Fat Research Articles

Консервирование проб сырого молока пищевой добавкой низин (Е-234)

In order to preserve the initial organoleptic, physico-chemical and microbiological parameters, raw milk samples for veterinary and sanitary examination are transported to the laboratory in a chilled form within a short period of time. Preservatives, which eliminate the need to cool samples, affect the initial milk parameters, pose a danger to laboratory workers and change organoleptics. This paper presents data on the effect of the safe food additive nizin (E-234) at a concentration of 0,03 g/0,5 l on the initial organoleptic (taste, color, odor and consistency) and physico-chemical (mass fraction of fat, protein, skimmed milk residue (SOMO), density, titrated acidity) indicators milk stored at room temperature. It was found that nisin slows down the change in physico-chemical parameters due to spoilage, but causes an increase of 0,14 % in the mass fraction of protein, 1,28 kg/ m3 in density, 0,32 % in the mass fraction of SOMO after 24 hours of experiment. Two methods of reducing the concentration of nisin in the samples were tested: heat treatment of milk and dilution of the preservative before each application. Heat treatment had a weak effect, the indicators decreased by an average of 0,04 %, 0,07 %, 0,22 kg/m3 for protein, SOMO and density, respectively. The second method turned out to be simpler and more effective – the true values of protein, SOMO and density indicators were preserved for the first 6–18 hours of sample storage.

Influence of feed mixtures on the productivity of cows and chemical composition of milk during the period of increasing the milk yield

There is a wide variety of climatic zones in the huge territories of our country, which require special approaches to feeding and housing of animals. Providing animals with adequate and rationed feeding under the conditions of the Northern Trans-Urals and Siberia is a difficult task due to the long stall period. The purpose of the work was to determine the infl uence of diff erent methods of feed distribution such as separate and feed mixture on milk productivity of cows and the chemical composition of milk during the period of increasing the milk yield. It was found that the milk yield of natural fat content during the fi rst 100 days of lactation in the experimental group of cows was 325 kg or 10,21 % higher than in the control group. Milk fat yield was obtained from the cows of the experimental group by 16,5 kg or 13,80 % more compared to the animals of the control group. The mass fraction of fat in the milk of cows in the experimental group was higher by 0,12 abs.%. However, the difference between groups in milk yield, milk fat content and milk fat yield was statistically insignificant. The difference in the content of protein, ash, calcium and phosphorus in the milk of the experimental animals was also insignificant, although there was some advantage in the content of these indicators in the experimental group, where the feed was fed in the form of the feed mixture. It was found when analyzing economic indicators that for cows in the control group the prime-cost of 1 kg of milk was 16,49 rubles, which was by 1,53 rubles or 3,91 % more than in the experimental group. At the same time, the level of profitability of milk production in the experimental group was higher than 12,66 abs.% compared to the control group.

Влияние пробиотиков на молочную продуктивность и технологические свойства молока коз зааненской породы

The article presents the results of experimental studies to study the effect of feeding probiotic feed additives Kluver Pro and BeneFIT Basic on milk productivity, composition and technological properties of milk from Saanen goats. It has been established that feeding probiotics Kluver Pro and BeneFIT Basic as part of the diets of lactating goats of the Saanen breed helps to increase milk yield by 9,5‑4,4% (p≤0,001), the mass fraction of fat in milk - by 0,73% (p≤0,05) and 0,11%, mass fraction of protein in milk - by 0,25% (p≤0,05) and 0,19%, as well as milk clotting time - by 7,3% and 5,4% (p≤0,001) and the formation of a denser rennet curd, which is a desirable property in the production of fermented milk products and cheese making

Productivity and milk quality of Saanen and Anglo- Nubian breeds of goats under the conditions of the Lower Volga region

Prospects for the development of dairy goat farming and goat milk production in many countries of the world, including Russia, are directly related to the dietary and healing properties of the product. An urgent problem is the comparative assessment of the adaptive and productive traits of dairy goats of imported selection under various ecological and climatic conditions of Russia, including the conditions of the sharp continental climate of the Lower Volga region. The purpose of the work was to give a comparative assessment of the eff ectiveness of breeding lactating goats of Saanen and AngloNubian breeds of imported selection under the conditions of the sharp continental climate of the Lower Volga region. The object of research was imported dairy goats. Two groups of female goats of Saanen and Anglo-Nubian breeds of the fi rst lactation of 10 heads in each were formed, taking into account their live weight, age of insemination and origin. The duration of the scientific and farm experiment was 210 days.Consistently high milk yield was found in goats of Saanen breed compared with the milk yield of their herdmates of Anglo-Nubian breed. The signifi cant diff erence in milk yield in favor of Saanen goats by months ranged from 13,24 to 16,51 % (p < 0,05). In general, during lactation the superiority of Saanen goats over their Anglo-Nubian herdmates in terms of milk yield was 61,2 kg or 15,75 %. A comparative analysis of quality indicators revealed a significant superiority of milk from goats of Anglo-Nubian breed such as in the mass fraction of fat by 1,48 abs.% (p < 0,05), in the mass fraction of protein by 0,24 abs.% (p < 0,05), in terms of milk fat yield by 3,15 kg (p < 0,05). It was found as a result that in the production of milk from goats of Anglo-Nubian breed, the level of profitability of milk with basic fat content (3,5 %) was higher by 27,78 abs.% compared with herdmates of Saanen breed.

Productivity and milk quality indicators of cows of the created “Bashkir type” black-and-white breed with the introduction of the balanced energy complex “Felucen K1-2” into the diet

The volume and quality of milk are the determining indicators of the efficiency of dairy farming. The diet of dairy cows has a significant impact on the biological parameters of milk productivity and production characteristics of milk. The work was carried out to determine the optimal dosage of the energy complex “Felucen K1-2” in the diet of cows of the created “Bashkir type” black-and-white breed in the conditions of the agricultural production complex “Hero” of the Chekmagushevsky district of the Republic of Bashkortostan. To achieve this goal, milk productivity was determined for 100 days of lactation, for 305 days, and also determined the dynamics of average daily milk yield by month of lactation. For the experiment, 48 cows were selected, divided into 4 groups of 12 animals each. The energy complex “Felucen K1-2” was added to the diet of cows in the experimental groups in the amount of 250 g, 300 and 350 g of the additive per animal per day. The results of the studies indicate an increase in the mass fraction of fat and protein in milk from cows that consumed the energy complex. This is observed both in dynamics over the months of the experiment and in the total amount for the entire period of research. The use of the additive in the diet of animals showed its effectiveness and contributed to an increase in milk yield per cow and improvement in the quality of milk, while the maximum effectiveness was observed at an average dosage (300 g per day per cow).

Evaluation of the quality of cow’s milk when using a mineral feed additive

Optimal cow feeding is the basis for successful dairy production, since feed costs can be up to half the cost of milk. An effective feeding program should achieve several goals: planned milk productivity, increased consumption of dry matter and improved functioning of the rumen microflora. Feed additives that affect the animal’s body play an important role in the diet, which is expressed in an increase in the average daily weight gain, a decrease in conversion rates and an improvement in metabolic processes. However, it is important to remember that additives alone cannot guarantee high productivity or economic benefits of dairy production. The purpose of this study was to study the effect of the multicomponent feed additive “Felucene” on the hygienic quality and safety of cow’s milk. The experiment was carried out in an educational and experimental farm, where, according to the principle of analogues, two groups of dairy cows of 40 heads each were formed. Both groups received the basic diet adopted by the farm, but the first group additionally received “Felucene” at the rate of 5 g per 1 kg of body weight. The analysis of milk composition and productivity was carried out on the 10th, 30th, 60th and 90th days of the study. The use of Felucene led to a 10% increase in dairy productivity of cows and improved milk quality characteristics: the mass fraction of fat increased by 0.09%, protein — by 0.20%, lactose — by 0.18%. The number of fat globules increased by 22%, and the content of the casein fraction increased by 10%. At the same time, the volume of milk corresponding to Class I in rennet fermentation and thermal stability increased by 18% and 17%, respectively.

Development of camel milk cheese technology and research of qualitative characteristics

Recently, interest in the production of camel milk and products from it has increased due to its nutritional and medicinal properties, including camel milk cheeses.In this study, the technology of cheese from non-pasteurized camel milk using mesophilic and thermophilic starter cultures was developed. The composition of camel milk and its microbiological safety indicators were studied. Next, three experimental types of camel milk cheese were prepared, where the physico-chemical composition, cheese yield, mineral composition and organoleptic parameters were determined. Thus, the content of the mass fraction of fat in the studied samples ranged from 25.45 to 22.13%. The mass fraction of solids for all samples was in the range of 50.50-62.30%; ash content was 3.05-3.65%; and the mass fraction of proteins was 17.49, 22.19%, respectively, in the control sample, cheese using mesophilic and thermophilic starter cultures. The cheese yield ranged from 115.20g/l to 137.98 g/l. The mineral composition of camel milk cheese showed that macronutrients such as Na, Mg, Ca, K, P. predominate in all samples. Also, all experimental samples of camel milk cheese had high organoleptic characteristics.

Effect of carbohydrate level in the diets of Kholmogor cows on milk productivity and milk quality

The effect of the diets with different ratio of easily digestible carbohydrates on milk productivity and milk quality of high-yielding Kholmogor cows during the milking period was studied. The research and production experiment on the cows was conducted in the Arkhangelsk region in 2022. Selection of animals in the control and experimental groups was carried out by the method of pair-analogues under the stall barn system. Two groups of cows participated in the research: experimental and control groups of 10 cows each. The experiment lasted for 100 days. Carbohydrate-protein mixture was used as a carbohydrate supplement to the diets of experimental animals in the amount of 1.5 kg per head per day. Selective milk quality control for mass fraction of fat, protein, lactose, dry matter, milk solids non-fat (MSNF), freezing point, urea and somatic cells were determined on a Bentley Combi 150 high-speed infrared milk analyzer at the Selective Milk Quality Control Laboratory. It was found that the sugar-protein ratio in the experimental group was twice higher (0.58) than in the control group (0.29), due to the presence of carbohydrate supplementation in the diet. The increase in milk productivity of the animals by 4.6 and 0.14% of the protein level in milk at inclusion of carbohydrate-protein mixture in the amount of 1.5 kg per one head per day in the diet was established. A 3.2% decrease in the level of urea in milk was recorded, indicating a more efficient use of amino acids by the animals in the process of metabolism at the same level of absorption of ammonium forms while increasing the level of simple carbohydrates in the diet. The positive effect of this additive on the content of dry skim milk residue, which increased in the milk of the cows of the experimental group by 0.128 absolute % (abs.%), was revealed. Application of the carbohydrate-protein mixture in the amount of 1.5 kg per one head per day and control over the quality of produced products will increase the milk productivity of cows, improve the quality of products, increase the productive longevity of dairy cattle.

The Development and Adaptation of a Predictive Model of Full-Factor Optimisation of the Basic Probiotic Fermented Dairy Product Technological Process

Introduction: In the conditions of rapidly developing markets and the increasing needs of the population for new types of products with long shelf life, there is a need to expand their range, further improve their quality and biological value, and modernize traditional technologies. The main means of achieving these goals is to increase the efficiency and quality of scientific research and accelerate the introduction of scientific achievements in industry. The latter will make adjustments to accelerate the development of effective technologies of whole-milk products. The use of new methods of experiment planning in order to optimize technological processes will reduce the duration of research on the creation of new types of products.Purpose: The article is devoted to the research related to the development and adaptation of a predictive (mathematical) model for optimization of the technological process of probiotic fermented dairy product production. This approach will allow to ensure the design of a certain set of formulations for probiotic fermented dairy product, in which the relative biological value (RBV) will correspond to the maximum value at satisfactory given process parameters.Materials and Methods: The objects of research were: probiotic fermented dairy product manufactured in accordance with the developed mathematical model of the process. The search of specialized literature was carried out using electronic databases: E-library, Scopus, MDPI, Science Direct. Mathematical processing of experimental data for the development of the probiotic fermented dairy product model was carried out using Microsoft Excel 2010 (Microsoft Corporation, Ink.) with the "Solution Search" add-in, as well as specialized software packages TableCurve 2D v.5.01 (SYSTAT Software, Ink.) and Wolfram Mathematica 10.2 (Wolfram Research, Ink.).Results: A mathematical model for optimization of the technological process of probiotic fermented dairy product production was developed. A full-factor experiment (FFE) was conducted, in which the mass fraction of sucrose ( , %) and fat-protein index (r) - the ratio of the mass fraction of fat to the mass fraction of protein in the normalized mixture in the intervals from 0 to 10 and from 0 to 1.5%, respectively, were taken as independent factors. RBV was taken as the resultant factor. Based on the results of the research, a refined mathematical description of the dependence of RBV indicator on the mass fraction of sucrose and fat-protein index was obtained. The set of data on the influence of the mass fraction of sucrose on the dynamics of local maximum of RBV and the dynamics of the corresponding values of the mass fraction of fat showed that the maximum of RBV equal to 244.866% corresponded to the mass fraction of sucrose equal to 7.31%. The latter corresponded to the optimum fat-protein index of 1.241. In order to ensure maximum RBV, the lower limit of the mass fraction of fat had to correspond to 3.475%. The analysis of the FFE data showed the presence of additional corrective factors of RBV indicator dependence on fat and protein mass fraction indices. To refine the developed model taking into account additional factors, a correction factor (Q) was introduced into it.Conclusion: Approbation of the optimization model of the technological process of probiotic fermented dairy product production and the obtained mathematical dependencies can serve as a criterion for the formation of a set of formulations for the production of sugar-containing fermented dairy products with a high potential of relative biological value. It should be taken into account that the definition area of this approach is limited in terms of mass fraction of fat in the range from 0.06 to 4.84% and mass fraction of protein - from 2.8 to 3.9%. With this approach (model development) it is possible to analyze promising modes for the studied process, which in real conditions at the experimental stage are not always possible to obtain. The development of this model will significantly reduce the duration of research on the optimization of the technological process.

Development of Technology for the Production of Meat Products of the "Halal" Category for Functional Nutrition

The article is devoted to the development of technology for meat products of the "Halal" category. The authors consider the main problems of the meat industry in the field of the development of meat products of the "Halal" category in accordance with the National Program "Development of meat farming for 2018-2027", as well as the peculiarities of the production of meat products of the "Halal" category in Kazakhstan. A technology for the production of sausages for frying of the "Halal" category based on minced turkey and beef meat for functional nutrition has been developed, organoleptic, physico-chemical parameters of the new product have been studied. The mass fraction of protein is 8 %, the mass fraction of fat is 7 %. The authors of the article have developed a technological scheme for the production of a new product of the "Halal" category, which includes: acceptance of raw materials, cutting, deboning, veining, grinding to 2-3 mm of meat raw materials. At the next stage, meat is cooked at t 2-4 0C for 12 hours, minced meat is prepared (adding jerusalem artichoke 3 %, adding vitamin premix "Rovifarin" in an amount of 1.0 %, as well as spices and garlic according to the developed recipe). At the next stage, the minced meat is stuffed into natural shells with a diameter of (32-44) mm, cooled at t (4 + 2) 0C, stored at t (4 + 2) 0C for 36 hours. During the microstructural study of a sample of boiled and smoked sausage produced using traditional technology, it was found that the mass of the sample was formed from large fragments of muscle, fat and connective tissue (0.7-1.4) microns. The layout of the structural elements of the minced meat is dense, vacuoles and microcapillaries are rounded in shape, sometimes without clear boundaries, merged, with a size of (60-300) microns.

Влияние белкового концентрата на качественные показатели козьих сыров

Purpose. To determine the effect of sunflower protein concentrate on the amino acid composition of cheeses made on the basis of goat's milk. Materials and Methods. In the conditions of the complex analytical laboratory of VRIMMP, 3 samples of semi-hard cheese were produced, one of which was a control without additives and 2 – experimental (No. 1 and No. 2) with a percentage of protein concentrate of 1.0 and 2.5% of the total weight of the cheese. Cheese samples were produced using traditional technology in accordance with GOST R 52686-2006. The active acidity of the samples was monitored using a portable pH meter testo 206-pH2 with the function of determining pH and temperature. The protein content was studied using an analyzer based on the Kjeldahl method. Indicators of the mass fraction of fat were determined using glass butyrometers type 1-6 according to GOST 5867-90. The mass fraction of moisture was determined by drying the sample in calcined sand at a temperature of 103°C. Analysis of the amino acid composition of the finished samples was carried out on a Kapel 105M analyzer (Lumex LLC, St. Petersburg, Russia). Results. The protein content in cheese sample No. 1 is 1.4% higher than in the control, and the content of this indicator in sample No. 2 exceeds the control by 2.8%. The amino acid composition in the samples in which protein concentrate was introduced into the recipe exceeds the content of this indicator in the control sample, which indicates a beneficial effect of the introduced component on the nutritional value of the finished product. The moisture content in the experimental samples decreased compared to the control due to the introduction of the additive and an increase in dry matter: in sample No. 1 – by 1.42%, and in sample No. 2 – by 2.86%. A slight increase in fat was found in cheese samples No. 1 and No. 2, but the indicator was within the normal range, which corresponds to this type of product. Conclusion. The use of goat milk as a raw material for the production of various types of cheeses is a promising direction for dairy producers food products. Rich composition makes goat's milk an indispensable food product for both children and adults. Compared to the milk of other animals, goat's milk is easily digestible, has hypoallergenic properties, due to which it is in high demand among people watching their diet or suffering from various types of food allergies. The conducted research and obtained data indicate the prospect of using this type of raw material as a complete base, and the use of protein concentrate in the production formulation will allow to obtain an enriched product with increased protein content.

Improving the technology of waxes obtaining from oil and fat waste

The object of the research is the extraction of waxes from the waste of the oil and fat industry – spent perlite. As a result of oil winterization, a significant amount of spent filter powders is formed, the disposal of which poses a danger to the environment. At the same time, winterization waste contains a significant amount of oil and wax, which are important components of many types of products. Oil and wax extraction involves the use of volatile, fire-hazardous solvents. An urgent task is to develop new safe and effective technologies for obtaining oils and waxes from winterization waste. The technology of extracting waxes from spent perlite, obtained as a result of winterization of sunflower oil, which involves treatment of perlite with sodium chloride solution, was investigated. Perlite was used according to SOU 15.4-37-210:2004 (CAS Number 93763-70-3) with indicators: mass fraction of fat – 20.1 %, peroxide value – 19.5 ½ O mmol/kg, acid value – 3.5 mg KOH/g. The temperature of mass settling after treatment with sodium chloride is 20 °C, the duration – 10 hours. The following rational conditions for perlite processing using sodium chloride were determined: the concentration of dry sodium chloride (by weight of perlite) – 35.0 %, the duration of mass boiling – 30 minutes. Under these conditions, the experimental value of the saponification value of the obtained wax was 120.5 mg KOH/g. Wax quality indicators: melting point 71.5 °C, acid value 1.6 mg KOH/g, mass fraction of moisture 0.63 %. The obtained results make it possible to obtain high-quality waxes from the waste of the oil and fat industry using a safe and affordable substance (sodium chloride). This will make it possible to avoid the need for waste disposal and increase the profitability of oil and fat enterprises due to obtaining valuable products from production waste

Realizing the genetic potential of black-and-white cows of different genotypes by the kappa-casein gene

Milk quality indicators are one of the main components of the breeding value of dairy cattle. The experience of many countries demonstrates that the Holsteinization of local cattle breeds is accompanied by an increase in the volume of milk produced while reducing its quality characteristics in particular to its cheese suitability. Solving this problem only by means of traditional breeding is difficult but it is possible to facilitate this task with application of modern molecular genetic methods and marker-oriented selection. The objective of the research was to assess the genetic potential of dairy performance of cattle with different genotypes by the kappa-casein gene (CSN3). The study was conducted on 104 purebred Russian black-and- white cows selected from the herds of the Yakovlevskoye APC and Raslovskoye APC. It was determined that the desired CSN3BB genotype was most common in 61 % of animals. As part of the study, the comparison of the experimental animals' own milk productivity with the productivity of their ancestors was carried out which made it possible to assess their genetic potential. The analysis showed that in the Yakovlevskoye APC, the protein content in milk in carriers of the CSN3AA genotype was significantly less than in carriers of the CSN3AB (P < 0.05) and CSNBB (P < 0.001) genotypes. There were no statistically significant differences in other productivity indicators, although the carriers of the CSNAB genotype (100.9%) differed in the greatest realization of the genetic potential in terms of the mass fraction of fat in milk, and cows with the CSNBB genotype (106.7 and 103.9 % respectively) in milk yield and protein content in milk. In the Raslovskoye APC, the greatest realization of the genetic potential in milk yield (119.5 %) was distinguished by carriers of the CSNAA genotype and the greater potential of fat and protein in milk were shown by animals with the CSNBB genotype (112.3 % and 103.7 %, respectively). Thus, the polymorphism of bovine kappa-casein gene has a significant impact both on the protein content in milk and on the realization of the genetic potential for this indicator of productivity. The obtained research results are important for breeding work with Russian black-and-white cattle aimed at improving the cheese suitability of milk.

Роль липолитических ферментов в улучшении органолептических показателей низкожирных сыров

Lipolytic enzymes can improve the sensory profile of low-fat cheeses. In this study, bovine lipase improved the flavor of semi-hard cheese with a 30.0% fat mass fraction.

ВЛИЯНИЕ СВЕТЛОЗЕРНОЙ РЖИ И ПОРОШКА САХАРНОЙ СВЕКЛЫ НА КАЧЕСТВО БИСКВИТНОГО ПОЛУФАБРИКАТА

In order to expand the range of flour confectionery products for a healthy diet, the possibilities of using cheap and affordable plant raw materials rich in nutrients have been studied. The main raw material is flour from light-grain rye of the Pamyati Bambysheva variety of the FASC of the South-East breeding. As a substitute for white sugar, powder from sugar beet root crops grown in the Balakovo district of the Saratov region was used. The evaluation of organoleptic indicators of the quality of products was determined according to GOST 14621-78, and a tasting assessment of the quality of finished products was carried out, quality indicators were evaluated on a 9-point scale. Physico-chemical parameters were determined according to generally accepted methods: the mass fraction of sugar – according to GOST 5903-89, the mass fraction of fat – according to GOST 31902-2012, ash content – according to GOST 5901-2014, humidity of products – according to GOST 5900-2014. The foaming ability, density and stability of the whipped mass were determined in the work. As a result of research, it can be concluded that when wheat flour is replaced with flour from light-grain rye of the Pamyati Bambysheva variety, a pleasant smell and taste are noted in the finished biscuit semi-finished product, according to physico-chemical indicators, the mass fraction of sugar and fat decreases, which gives the products dietary properties. The nutritional and energy value of the biscuit semi-finished product changes in a positive direction, as the carbohydrate content decreases, and the content of polyunsaturated omega-3 and omega-6 fatty acids, vitamins, macro- and microelements, many of which are antioxidants, increases markedly. Therefore, the results of these studies make it possible to position the finished product as a product with functional and dietary properties.

The process of yak milk fermentation by polycomponent starter culture

The paper presents a comparative characteristic of the fermentation processes of yak and cow milk samples with a high fat content of 1.5% and 6% with a multicomponent starter culture, which includes Lactobacillus acidophilus, Bifidobacterium animalis subsp Lactis and Streptococcus thermophiles. Acid formation in the process of milk fermentation under the influence of the starter microflora was assessed by the dynamics of changing in titratable (Ac) and active (pH) acidity over time. The course of the formation of the structure of the resulting clot was monitored on a rheometer, fixing the viscosity characteristics of the fermented milk clot in dynamics. It has been established that the increase in acidity occurs more intensively in yak milk in comparison with cow's milk with a corresponding acceleration of the formation of a fermented milk clot. In conclusion, the resulting clots were subjected to sensory analysis with the identification of the best sample, which was fermented yak milk with a fat mass fraction of 6%.

Influence of humic acids on of cows milk productivity and indicators of milk quality and safety

The study was conducted to determine the effect of humic acids added to the diet of lactating cows on their milk productivity and physicochemical parameters of milk. The study was conducted on 14 Holstein cows of German breeding, which were fed 20 g/100 kg of live weight per day of an organic feed mixture containing 40.5% humic acids and 22% fulvic acids to their basic diet for 30 days. Milk samples were taken twice, before the use of the organic feed mixture and after 30 days of use. An increase in milk productivity by 5.8% was observed in 86% of lactating cows, the mass fraction of fat in milk increased A slight increase in milk fat content (p<0.1) is associated with an increase in this indicator in the milk of 72% of experimental cows from 0.2 to 0.92%. In the milk of the rest of the cows, the fat content of the milk did not change, but the average index for the group increased by 0.38%. The mass fraction of proteins after 30 days of using the organic feed mixture, an increase in the mass fraction of proteins in the milk of cows was noted on average for the group by 0.2% (р<0.05), with an average indicator for the group of 3.5±0.06% (3 ,12–4.2%). In the milk of 80% of the examined cows, the mass fraction of proteins increased from 0.12 to 0.9%, in 20% of the cows the mass fraction of protein in milk did not change, but the values corresponded to the basic norm (3.0%). An increase in average daily milk yield from 36.73±0.6 kg (35.43–38.9) at the beginning of the study against 38.85±0.19 kg (37.3–39.9; p<0.01) at the end of the experiment, which is 2.12 kg more and indicates a positive effect of humic acids on milk productivity of cows. The number of somatic cells in the milk of cows after a 30-day use of an organic feed mixture based on humic acids did not change and amounted to 104.78±19.09 thousand/cm3 (20.0–218.0), against 104.47±23, 5 thousand/cm3 (11.0–246.0) at the beginning of the study. In the milk of 28.5% of cows, at the end of the study, a slight decrease in the number of somatic cells was noted from 35 to 55 thousand/cm3, in the milk of 21.4% of cows, the number of somatic cells increased slightly from 19 to 74 thousand/cm3, which corresponds to the physiological norm . Milk urea nitrogen is used to assess the energy-protein balance in feed; a reduced value at the end of the study ranged from 7.1 to 18.5 mg/100 ml, indicating a crude protein deficiency in the diet. Key words: humic acids, number of somatic cells, mass fraction of fat, mass fraction of proteins, lactose, milk urea nitrogen, milk productivity.

Are thyroid hormone levels and sarcopenia in elderly patients associated with type 2 diabetes mellitus and euthyroidism?

Aim to study the relationship between thyroid function parameters (free T3 (FT3), free T4 (FT4), FT3/FT4 ratio), thyroid-stimulating hormone (TSH) and parameters characterizing sarcopenia (muscle mass and strength, physical performance) in patients with type 2 diabetes mellitus (T2DM) and euthyroidism.
 Material and methods. The study included 312 elderly patients with T2DM in a state of euthyroidism (mean age 65.39 2.28 years). In all participants the following parameters were measured: anthropometric parameters, thyroid hormones (FT3, FT4), TSH, fasting blood glucose, glycated hemoglobin (HbA1c), fasting C-peptide and insulin, lipid profile, body composition, handgrip strength, walking speed.
 Results. Sarcopenia was prevalent in 26.9% of T2DM patients with euthyroidism. A binary logistic regression analysis adjusted for age, gender, smoking and alcohol consumption, T2DM duration, hypertension, HbA1c level, eGFR, TG, HDL and fat mass fraction showed that the high-normal FT3 level (OR = 0.522, 95% CI: 0.3040.895, p = 0.018), a low-normal FT4 level (OR = 1.126, 95% CI: 1.0091.258, p = 0.034) and an increased FT3/FT4 ratio (OR = 0.923, 95% CI: 0.8790.969, p = 0.001) were associated with a low prevalence of sarcopenia. FT3 concentration was positively associated with muscle strength (OR = 0.525, 95% CI: 0.3050.902, p = 0.020) and walking speed (OR = 0.443, 95% CI: 0.2590.758, p = 0.003), while FT4 concentration was negatively associated with muscle mass (OR = 1.114, 95% CI: 1.0091.232, p = 0.036). The FT3/FT4 ratio was positively associated with muscle mass (OR = 0.943, 95% CI: 0.9050.981, p = 0.006), muscle strength (OR = 0.945, 95% CI: 0.9010.992, p = 0.021), and walking speed (OR = 0.934, 95% CI: 0.8940.975, p = 0.002). TSH levels were not associated with sarcopenia.
 Conclusion. The high FT3/FT4 ratio is significantly associated with a low risk of sarcopenia in T2DM patients with euthyroidism.

МОЛОЧНАЯ ПРОДУКТИВНОСТЬ И КАЧЕСТВО МОЛОКА КОРОВ С РАЗНЫМИ ГЕНОТИПАМИ ЛЕПТИНА И ЛИНЕЙНОЙ ПРИНАДЛЕЖНОСТИ

A review of the scientific literature has shown that the genotype by loci of the Leptin (LEP) gene and linear affiliation to the leading Holstein breed of cows have an impact on milk productivity and the quality of their milk. The purpose of our research was to study the milk productivity and qualitative composition of the milk of Tatarstan-type cows with different genotypes according to the loci of the Leptin gene and linear belonging to the Holstein breed. The research was carried out in the conditions of the agricultural company "Agrofirma Rassvet" of the Kukmorsky district of the Republic of Tatarstan on the livestock of 79 cows of the Tatarstan type. The Tatarstan type is one of the leading dairy cattle breeds bred in the Republic of Tatarstan, and created by crossing the Kholmogorsky, Black and White, and Holstein breeds, while the bloodline was 1/8 Kholmogorsky + 1/16 Black and White + 13/16 Holstein. As a result of a molecular genetic study (PCR-RFLP), the animal population was sorted into groups, taking into account the genotype by the loci of the Leptin gene. The conducted studies have shown that in Tatarstan-type cows after the first lactation, the highest milk yield indicators, the amount of fat and protein in milk were noted in animals with the leptin gene genotypes LEP/CC and LEP/CT in comparison with peers of the LEP/TT genotype. However, in terms of the mass fraction of fat and protein in milk, the trend was reversed. Also, among the cows of the Tatarstan type, according to the first lactation, the highest values of milk productivity indicators (milk yield, amount of milk fat and protein) are in cows with the LEP/CC genotype of linear belonging to the Holstein breed, namely W. Ideal 933122 and R. Sovering 198998.

Correlations of reproduction and productive traits in Holstein cows during dynamics on lactations

The task facing livestock breeders is to get a calf from each cow during the calendar year. Insemination of cows in the fi rst two months after calving is a necessary condition for increasing the rate of reproduction of livestock on the farm and increasing the economic effi ciency of the dairy industry. The purpose of the work was to evaluate the correlations between reproduction and productive traits in dairy cattle of Holstein breed, taking into account age in lactations. It was established as a result of the research that the herd has a large number of young cows in their fi rst and second lactations. The highest productivity indicators were found in cows in the third lactation, then there was a decrease in milk yield until the end of their use with slight fl uctuations in the direction of increase or decrease in milk yield, but in any case they turned out to be lower than in the third lactation. The mass fraction of fat in milk is a fairly stable indicator, as is the mass fraction of protein. The duration of the period of open days generally exceeded the optimal norms by 13–24 days or 14,4–26,7 %. This leads to the increase in the duration of lactation and the calving interval. The reproductive effi ciency coeffi cient ranged from 0,97 (9 and 10 lactations) to 0,91 (1, 5 and 11 lactations) and was mostly below 0,95, but tended towards this indicator. It can be concluded that the breeding stock in the dairy cattle herd of the breeding farm has satisfactory reproductive traits and there are certain problems with reproduction. The reliable influence of the duration of the period of open days on the milk productivity of cows has not been determined. Based on milk yield during early lactation we can predict about the further productivity of cows.