Comparative assessment of reproductive capacity of boar-sires depending on the breed and season

The article highlights the results of the reproductive capacity of different breeds of boar sires in the farms of eastern, southern, and central regions of Ukraine in dynamics over three years are given. It represented the influence of the year's season on sperm quality by estimating the ejaculate volume, concentration, and motility of sperm of boars-sires of the different breeds and their hybrids. Data were also calculated on the culling of ejaculates of boar sires of various breeds for the years 2019–2021 in the dynamics. In a comparative aspect, the indicators were analyzed by the following genotypes: Large White, Ukrainian Meat, Landrace, Duroc, Yorkshire, and synthetic line Makster. The reproductive capacity of boars was within the limits of the indicators for the elite and first classes. However, specific differences were observed between boars of different breeds, which were constant and took place during the three studied years. The difference in the concentration of sperm in the ejaculates of the Ukrainian Meat breed gradually decreased starting from 2019 and was the smallest in 2021. The highest ejaculate volume was found in boars of the Ukrainian meat breed (310.9 ± 113.2 cm3), and the sperm concentration was the highest in boar sires of the Large White breed (215.7 ± 83.5 million/cm3). On the other side, hybrids of the Large White breed had low indicators compared to other groups of animals (Large White × Yorkshire – 184.2 ± 68.5 million/cm3, Large White × Makster – 189.0 ± 59.7 million/cm3). Sperm motility did not undergo significant breed differences: the average annual indicator of motility was 7.6 ± 0.09 points, and it was the highest in the winter period (8.6 ± 0.11 points), however, for the established variances; the dilution was used 1.65–3.58 times and a high percentage of unusable sperm (15.4–29.4 % of the total amount) was established in a large number of samples. According to the results of the annual analysis of the sperm production of boars, a high degree of culling of ejaculates was established for various reasons (high level of sperm agglutination (52.3–74.0 %), low concentration of germ cells (14.5–29.8 %), presence of foreign impurities (5,8–12.4 %). The highest percentage of culling was in summer (20.3 %). Thus, the obtained results showed the breed and seasonal characteristics of the reproductive capacity of breeding boars

Project Method Development in Study of Chemistry in Vocational and Pedagogical University

The paper considers the problem of realization of the project method in the study of chemistry in vocational and pedagogical university. The research urgency is caused by the necessity of more complete assimilation of professional and research competences. The authors have developed a model of organization of project activity of university students. The theoretical rationale for the project method of teaching chemistry is presented. The results of studies of the effectiveness of the developed model are given. Special attention is paid to determination of readiness of students to project activities. Novelty of research consists in a new approach to the study of chemistry based on the implementation of professionally-oriented projects for students in non-core universities. The authors focus on the need for reasonable planning of the experimental work during project execution. It is noted that the result of the implementation of the experiment with the use of this approach was that the students’ satisfaction with project activities is at a high level. It is shown that the project method contributes to the level of students’ knowledge, mastering professional and research competencies. The authors propose the project activity as a supplement to the traditional form of teaching. The article can be helpful when using new technologies of teaching chemistry at the university

Біохімічний та мінеральний статус організму неплідних кнурів за гіповітамінозу А

A leading role in the occurrence of infertility in male domestic animals is played by nutritional deficiency factors, in particular vitamin A deficiency, which contributes to the development of morphological and functional changes in the reproductive system. The aim of the work was to determine the effect of vitamin A (carotene) deficiency on the biochemical and mineral status of infertile boars, in particular, to establish changes in the main biochemical markers and assess the state of the antioxidant defence system and indicators of mineral homeostasis (Calcium, Phosphorus, Zinc, Copper, Manganese and Cobalt). In the experimental group of animals, a probably low level of vitamin A was noted (by 54.2 % lower than the control group, P ˂ 0.001) due to a significant increase in the content of thiobarbiturate acid-reactive compounds (by 2.32 times, P ˂ 0.001) and a decrease in the activity of catalase and superoxide dismutase (by 47.3 % and 28.8 %, respectively, P ˂ 0.001). A decrease in haemoglobin concentration by 14.3 % (Р ˂ 0.001), total protein by 11.6 % (Р ˂ 0.01), the number of erythrocytes by 9.3 % (Р ˂ 0.01) and acid capacity by 9.1 % (Р ˂ 0.05). These results demonstrate a general decrease in metabolic processes in the body of infertile boars with vitamin A deficiency. The reduced number of erythrocytes in the blood of boars of the experimental group was mainly due to antiradical and antihypoxic abilities. It should be noted that catalase activity and the content of reduced glutathione in erythrocytes were probably lower than the control indicators by 53.1 % and 16.3 % (Р ˂ 0.001), respectively. In addition, taking into account the reduced indicators of haemoglobin content and the number of erythrocytes, a negative dynamics of oxygen metabolism was established. This is also confirmed by a probable increase in the content of 2,3-diphosphoglycerate in erythrocytes (by 67.5 %, Р ˂ 0.001). Also, in boars of the experimental group, the content of Calcium was lower by 25.0 % (Р ˂ 0.001) than the control indicators, and the content of Phosphorus decreased by 12.6 % (Р ˂ 0.05). Similar changes were observed in the levels of Zinc and Copper (indicators were lower than the control by 52.0 % and 28.0 %, respectively, Р ˂ 0.001). Note that the Manganese content in the blood of experimental boars was reduced by 20.9 % (Р ˂ 0.05), while the Cobalt level was lower by 16.1 % (Р ˂ 0.05). The obtained results showed a significant effect of A-vitamin deficiency on the general antioxidant activity and mineral homeostasis in barren boars.Провідну роль у виникненні неплідності самців свійських тварин відіграють аліментарно-дефіцитні фактори, зокрема А-вітамінний дефіцит, який сприяє розвитку морфологічних та функціональних змін у статевій системі. Метою роботи було визначення впливу дефіциту вітаміну А (каротину) на біохімічний та мінеральний статус за неплідності кнурів, зокрема встановлення змін основних біохімічних маркерів й оцінка стану системи антиоксидантного захисту та показників мінерального гомеостазу (Кальцію, Фосфору, Цинку, Купруму, Мангану й Кобальту). У тварин дослідної групи виявляли вірогідно низький рівень вітаміну А (на 54,2 % менший за групу контролю, Р ˂ 0,001) за значного зростання вмісту тіобарбітурат-активних продуктів (в 2,32 рази, Р ˂ 0,001) і зниження активності каталази і супероксиддисмутази (на 47,3 % і 28,8 % відповідно, Р ˂ 0,001). Також виявлено зниження концентрації гемоглобіну на 14,3 % (Р ˂ 0,001), загального протеїну на 11,6 % (Р˂ 0,01), кількості еритроцитів на 9,3 % (Р ˂ 0,01) та кислотної ємності на 9,1 % (Р ˂ 0,05). Дані результати демонструють загальне зниження обмінних процесів в організмі неплідних кнурів за А-вітамінного дефіциту. Еритроцитопенія у кнурів дослідної групи головним чином позначалася на антирадикальних й антигіпоксичних здатностях. Зазначимо, що активність каталази і вміст відновленого глутатіону в еритроцитах були вірогідно нижчими за показники контролю на 53,1 % і на 16,3 % (Р ˂ 0,001) відповідно. Крім того, враховуючи знижені показники вмісту гемоглобіну й кількості еритроцитів, було встановлено негативну динаміку метаболізму Оксигену. Це також підтверджено вірогідним збільшенням вмісту 2,3-дифосфогліцерату в еритроцитах (на 67,5 %, Р ˂ 0,001). Також у кнурів дослідної групи вміст Кальцію був меншим на 25,0 % (Р ˂ 0,001) за показники контролю, а вміст Фосфору зменшувався на 12,6 % (Р ˂ 0,05). Подібні зміни спостерігали у рівнях Цинку й Купруму (показники були нижчими за контрольні на 52,0 % і 28,0 % відповідно, Р ˂ 0,001). Зазначимо, що у крові дослідних кнурів вміст Мангану був зниженим на 20,9 % (Р ˂ 0,05), тимчасомі як рівень Кобальту був меншим на 16,1 % (Р ˂ 0,05). Отримані результати показали значний вплив А-вітамінного дефіциту на загальну антиоксидантну активність і мінеральний гомеостаз у неплідних кнурів

Under the influence of new educational technologies: the theory of electrolytic dissociation

The article describes a computer programs for study of the chemistry section, training calculations and knowledge testРассмотрены компьютерные программы для изучения студентами химии, выполнения ими практических заданий и проверки знани

Плоды свидины белой ( Swida alba ( L.) Opiz) — перспективный источник жирного масла

The paper deals with study of locating, content and composition of fatty oil in Siberian Dogwood’s fruits, pericarp and seed.Статья посвящена изучению локализации, содержания и состава жирного масла в плодах, околоплоднике и семенах свидины белой — Swida alba ( L.) Opiz

Annealing effect on temperature stability and mechanical stress at the “CdxPb1−xS film – substrate” interface

The article establishes the upper temperature steadiness limit of СdxPb1-xS supersaturated solid solutions obtained by chemical bath deposition. СdxPb1-xS (x = 0.06; 0.122; 0.176) and (x = 0.02–0.05) films remained stable under the heating up to 405–410 and 450 K, respectively. SEM studies have shown that heating of СdxPb1-xS films (x = 0.02–0.05) to 620 K leads to the structure destruction. Internal mechanical compressive stresses at the "СdxPb1-xS film-substrate" interface was calculated in the range of 300–900 K for the first time ever, the highest values reached 2000–2750 kN/m2 for a number of the films compositions. In contrast to solid solutions, the expansion stresses up to 100 kN/m2 were derived for the CdS layer at 900 K. The obtained temperature steadiness boundaries and the mechanical stresses of СdxPb1-xS films must be taken into account in the development of photonic devices based on such materials

Histomorphology of the ovaries of rabbits does during ovulation induced by the combined use of gonadotropins

Hormonal stimulation of folliculogenesis is a general method of increasing reproductive capacity in rabbits; however, studying the safety of the developed protocols remains an urgent scientific task. The use of hormonal agents is due to the physiological characteristics of rabbits, primarily coitus-dependent mechanisms of ovulation. Applying gonadotropin-releasing analogs depends on mature follicles ready for ovulation in the ovary. It, therefore, has limited effectiveness for rabbits of the “zero” cycle that have not yet given birth. Therefore, such females are recommended to use medications based on gonadotropins obtained from the serum of foal mares (eCG) or human chorionic gonadotropin (hCG). There is limited data on the combined use of gonadotropins, especially the long-term administration in different doses. Thus, the research aimed to conduct a morphological evaluation of rabbit's ovaries with combined serum and chorionic gonadotropins to stimulate folliculogenesis before artificial insemination to assess the safety of the proposed dosages and long-term administration. Stimulation of ovulation in rabbits of experimental groups was caused by the combined use of serum and chorionic gonadotropins (eCG – 400 IU; hCG – 200 IU) for experimental groups 1 and 2 at a dose of 40 IU and 24 IU, respectively. Females of the control group were induced to ovulate by subcutaneous injection of 0.2 ml of gonadotropin-releasing hormone analog. Ovaries were collected on the seventh day of gestation after the euthanasia of the rabbit with prior premedication. After dissection and macroscopic examination, the ovaries were fixed in a 10% aqueous solution of neutral formalin. Histological slides were made according to the general method by pouring in paraffin and subsequent staining with hematoxylin and eosin. The research has established that repeated (during five reproductive cycles) combined use of serum and chorionic gonadotropins has dose-dependent effectiveness and can cause dysfunction of ovaries and blood circulation. Pathological changes may acquire a systemic character with the manifestation of critical conditions for the health and life of rabbits. The stimulating effect of the combined use of eCG and hCG was detected at a dose of 40 IU, and the inhibition of folliculogenesis was observed at 24 IU. Since the premises for the hyperandrogenism were found microscopically, it was essential to investigate the level of androgens in the blood of rabbits after using a dose of 24 IU. At the same time, both doses of gonadotropins affect the reactivity of the endothelium, which is manifested by the presence of intravascular vesicles and changes in the rheological properties of blood

Individual Psychological Resources Forming Students' Resistance to Internet Addiction

The problem of Internet addiction has become increasingly relevant. The aim of the study is to analyze the psychological factors that help to prevent Internet addiction at youth age. The results of the empirical study of individual typological prerequisites of forming a resistance to Internet addiction among students are discusse

Auger spectroscopy of Cdpbs films obtained by chemical deposition

Films obtained by chemical deposition of thiourea onto a quartz substrate from the citrate-ammonia reaction mixture containing 0.01, 0.04 and 0.1 mol/l cadmium nitrate at constant concentration of lead salt is obtained. The formation of single- and two-phase films depending on the cadmium nitrate content in the reactor is established by X-ray diffraction, scanning electron microscopy and auger spectroscopy. © 2021 Author(s).Russian Foundation for Basic Research 18-29-11051mkThe work was financially supported by the grant project of Russian Foundation for Basic Research 18-29-11051mk and 20-48-660041ɪ_ɚ. The research was carried out within the state assignment of Minobrnauki of Russia (theme “Spin” No. ȺȺȺȺ-Ⱥ18-118020290104-2 and “Flux” No. ȺȺȺȺ-Ⱥ18-118020190112-8)