The paper examines the influence of stands of different species composition on the properties of sod-podzolic soils and the qualitative composition of humus. Forestry-taxation description of plantings and soil research were conducted on permanent trial plots of the IV, VIII and XI quarters of the RSAU-MTAA Forest Experimental District. It has been revealed that the thickness of forest litter under deciduous stands is 2-5 times higher than in soils under coniferous stands. Litter thickness under deciduous stands increases in September-October by 1-3 cm as compared with the summer months. Forest litter thickness under coniferous plantations remains practically unchanged from May to October. It has been established that the species composition of the stands does not affect the C_fa content in the soils, and there is no seasonal dynamics of this indicator. The C_ha: Cf_a ratio is a dynamic indicator, which differs in soils under deciduous and coniferous plantations and is characterized by seasonal dynamics.

The paper considers some issues relating to the evaluation of oxidation-reduction (redox) properties of soils using a system of titration methods with oxidizers and reducing agents, and con-trolled-potential coulometry on electrodes from a soil-coal paste. The redox status of soils can be additionally evaluated using the gas-discharge imaging method through determining the anti-radical activity of soil solutions and the content of antioxidants, carbon dioxide and oxygen, as well as positively and negatively charged complex compounds of cations, air ions in the soil, and the energy status of soils. It is shown that the amount of reduced substances increases in case of abundant soil moisture and increased humus content. The authors prove the reasonability of estimating the redox buffer capacity of soils and offer its mathematical description using 15 equations of pair correlation. In the pH range from 3 to 10, the value of AEh / ApH has amounted to 62.2 in the sod-podzolic soil and 43.9 in gray forest soil. Studies have proved the need to determine the Eh value in the root zone of plants in order to evaluate the redox status of soils. It is shown that plants adapted to the anaerobiosis conditions are highly prone to regulate Eh in the root zone and the absorption selectivity of individual elements. It has been found that to optimize the properties of soils and the “soil-plant” system, it is advisable to take the following joint measures: regulate the Eh factor of soils, inactivate the toxicants that appear in anaerobiosis, and introduce into the plants microelements that are an integral part of the redox enzymes of plants. It is proved that the most complete evaluation of the redox status of soils requires integral interpretation of redox properties, processes and modes to develop models of an optimal redox status of soils necessary to perform various ecological functions.

The authors prove a possibility of laboratory diagnostics of early stages of pregnancy in female horses. Exposure of a temperature-controlled mare blood samples to standing amplitude-modulated ultrasonic wave with a generation frequency of 0.88 MHz, an intensity of 0.05 W/cm² and a modulation frequency from 10 to 20 Hz for 15-20 sec leads to a significant change in the morphological state of blood cells. The use of simple and accessible methods of light microscopy has revealed the aggregation of leukocytes with the simultaneous absence of any signs of lysis and cellular destruction of erythrocytes in the blood of pregnant mares. The developed technique can be used for non-invasive ultrasonic examination of the blood of female farm animals in the early stages of pregnancy. Due to its simplicity and low cost, the technique can be implemented both as an independent diagnostic method, and as a supplement to the conventional veterinary clinical methods.

In 2016, the Dorper rams were brought to the Republic of Kalmykia. In the Russian Federation, this breed is new and there is little data on its use when crossed with other breeds. The research purpose was to study the effectiveness of crossing the ewes of the Kalmyk fat-tailed breed with rams of the Dorper breed, as well as the economically valuable qualities and biological features of the resulting hybrids in the conditions of the arid zone of Kalmykia. It was established that breeding efficiency (impregnation rate) in ewes of the experimental group was higher by 2.5%, and fertility (birth rate) was higher by 7.5% as compared to the control group. Mixed bred youngsters featured increased growth energy during all growing periods and reliably exceeded their peers of the control group at all ages in terms of live weight, as well as absolute, average daily, and relative increase in live weight. Animals showed a high blood content of hemoglobin, leukocytes, erythrocytes, total protein, albumin, alkaline phosphatase, and increased activity of transamination enzymes (ATT) and (ALT), which indicates the activation of redox processes in their bodies. Rams of the experimental group outperformed their peers from the control group in pre-slaughter weight by 6.03 kg, chilled carcass mass by 4.79 kg, slaughter yield by 5.19%, pulp mass by 3.99 kg, bones, cartilage and tendons by 0.8 kg The largest mass of Class I cuts was found in the carcasses of hybrid sheep and it amounted to 17.16 kg, which is 4.42 kg higher than that of purebred peers. Muscle tissue of hybrids contained more dry matter, protein and fat. It was characterized by a greater water-holding capacity of 2.8 7%. The content of amino acids in the meat of hybrid sheep was higher than that of control animals. Chemical and physico-chemical properties of tail fat proved to be of a good quality.

This paper is aimed at improving the system of assessing the breeding value of bulls by set complex indicators of their daughters’ lactation performance. The authors carried out studies using a database for first-calving cows of black-motley population of the Moscow region for the period 2011-2015. The authors used a previously optimized structure as the initial equation of the BLUP mixed model for assessing the genetic features of bull sires for each indicator of their daughters ’ lactation performance. This model takes into account and eliminates the paratypic effects on the variability of studied parameter to the greatest extent. To construct a selection index in the studied population, coefficients of heritability, as well as phenotypic and genetic variants (covariants) of traits were calculated. As a result, the form and weight coefficients for each trait in the selection index were determined and formalized. To determine the effectiveness of using the developed selection index, the breeding process in the population was simulated during the formation of animal breeding groups based on the different intensity of their selection. The results obtained convincingly prove the advantage of the selection index in assessing the genetic values of animals in terms of the totality of the analyzed traits and in their selection into breeding groups as the birth fathers of bulls and cows in the current population. The advantage of selecting animals according to the index was 3.0-10.0% as compared with the selection only for milk yield, milk fat and milk protein, and 1.7-30.9% for the fat and protein content. Thus, the study results convincingly prove the fundamental necessity to use a selection index when assessing animals (comprehensive assessment of breeding and productive features of individuals) and optimizing breeding programs for genetic improvement of dairy cattle breeds and populations in Russia.

Organic matter of milk is subject to a number of complex changes in its composition and properties under the influence of different factors during storage; new chemical components being formed that significantly change nutritional value, normal appearance, taste and smell of the product. Regulation of biochemical and microbiological reactions in the process of milk storage and processing is an important direction of the dairy industry. The purpose of the experiment was to identify the nature of the differential effects of antibiotics on the chemical composition, microbiological indicators and technological properties of raw milk and dairy products. During the study, it was found that an increase in penicillin concentration lead to a liquid and heterogeneous consistency of yoghurt, with a broken flaky clot, foreign flavor and odor. With the highest content of antibiotics in the product (0.016 mg/kg) the number of lactic acid bacteria was 3.2 x 10⁴ CFU/ml, while in its absence - 3.4 x 10^s CFU/ml. Statistically significant differences in the organoleptic properties of yogurt were observed at the highest concentration of levomycetin (0.0012 mg/kg) in terms of consistency, taste, and overall score. In the meanwhile, other studied concentrations of the antibiotic did not affect the consistency, taste and smell of the product.

The authors have made an assessment of the absorption capacity of a new sorbent based on the bun of the technical “Surskaya” hemp variety in relation to heavy metal ions: copper (II), chromium (III) and chromium (VI), using scanning electronic microscopy. It has been established that in the process of absorption, the bun surface morphology changes, namely, the number of micropores decreases. The use of special detectors has allowed to perform an elemental analysis of the surface of the studied samples. According to the data obtained, it can be seen that hemp bun absorbs both copper cathions (II) and sulfur in a sulphate ion form from 0.1 M of CuSO₄ solution. The content of sulphur has increased 13 times as compared with the original bun. The studied samples of the hemp bun are 3 times more actively sorbing trivalent chlorine (19.8 wt.%) from solutions than hexavalent chlorine (6.6 wt.%).

Immunogenetic evaluation is an important component of appropriate breeding and selection work. It allows keeping rigorous records of the origin authenticity and identify genotypes linked to productivity, as well as to breed cattle with desired or predicted parameters. It is impossible to perform blood grouping without specific reagents (monospecific sera), and their obtaining is important work conducted by the specialists of the Immunogenetic Evaluation Laboratory at the Ural Research Institute of Agriculture. Due to the decrease in the number and volume of reagents, it became necessary to produce them using the laboratory internal resources. Thus, the purpose of this work is to replenish the reagent bank with the required monospecific sera. In order to obtain monospecific sera, the authors used a method of cattle immunization with the selection of donor-recipient pairs. Upon sampling and selection procedures, 100 ml of blood was once taken from donor bulls and then admixed to recipient bulls in three steps 30 ml each time at an interval of one week. Donor herds of Ural-type cows and fattening bulls were immunized at agricultural breeding enterprises located in the Sverdlovsk Region: LLC Mezenskoye, Pervouralsk Integrated Agricultural Production Center, LLC Borodulinskoye, Integrated Agricultural Production Center - Kolkhoz named after Sverdlov, Patrushi Agricultural Company, After the immunization, serum is obtained from the blood of recipient bulls and analyzed with the method of dilution for titre and specificity. There are three ways to obtain monospecific sera: immunization, absorption, and elution. On the basis of this methodology, 41 reagents were produced at the Immunogenetic Evaluation Laboratory between 2008 and 2017, the titres of which varied from native (1:1) to 1:512.