IN VIVO AND IN VITRO EVALUATIONS OF UREA-BASED PRODUCTS IN CATTLE FEEDING

The main purpose of the present thesis was to improve the knowledge about the aspects of urea utilization in cattle diets in respect to rumen fermentation and animal performance. The first experimental part of the thesis consists of feeding trial with Italian Simmental fattening bulls (Exp. 1) and in vitro trial with continuous culture fermenters (Exp. 2). The aim was to study the effects of dietary substitution of soybean meal (SBM) with urea (U) within medium (M) and low (L) levels of intestinal digestible protein (PDI) on animal performance and on in vitro rumen fermentation characteristics. In Exp. 1, the average daily gain (ADG) of Italian Simmental finishing bulls was satisfactory (1.32 kg/d), however, both ADG and feed efficiency tended (P<0.10) to be higher in M diets. Slaughter traits were unaffected by dietary treatments. In Exp. 2, large differences in the ammonia concentrations were found between M and L diets over different sampling times (P<0.01 at T0, T1, and T2; P<0.05 at T3). In vitro DM digestibility tended to be higher for U diets (P<0.10). Molar proportions of butyrate were higher in M and U diets (P<0.01). Although the in vitro environment lowered diversity and richness of bacteria population and total VFA concentration (P<0.01), it allowed the growth of the major bacterial phyla found in vivo. The second experimental part consists of three in vitro trials. The aim was to evaluate the capacity of urea-treated cereals (barley and corn) for slow-release ammonia properties in vitro. In Exp. 1, milled untreated (CTR), urea-treated (UT) and urea-added (UA) samples were incubated in the rumen liquid and sampled for ammonia at 0, 0.5, 2, 4, 6, 8 and 24 h. The UT cereals released less ammonia than the UA (P<0.05), while the CTR showed the least ammonia concentrations (P<0.01). In Exp.2, CTR and UT samples in three physical forms: whole, coarsely and finely milled were incubated in distilled water for 1, 2, 4, 6 or 8 h, and then analyzed for N content. The N solubility of UT and CTR cereals changed according to the physical form (20.2 vs. 9.6%, 31.9 vs. 13.2% and 43.7 vs. 15.2% for the whole, coarse and milled, respectively, P<0.01 of interaction). In Exp.3, CTR, UT and UA milled samples were incubated in rumen fluid first for 96 h to determine a halftime (t1/2) and second, for t1/2 to measure gas production, degradability, microbial N, VFA and ammonia. In barley, UT and CTR treatments produced more gas than UA incubation, while in corn, UT and UA produced less gas than CTR (P<0.01). The highest microbial N was found for UT samples in both cereals (P<0.01). A lower butyrate concentration was detected for UT samples (P<0.01). The third experimental part consists of two in vitro gas tests. The aim was to test in vitro rumen gas production technique in differentiating slow-release urea (SRU) products. In the Exp. 1, five progressive urea doses (0, 25, 50, 75 and 100 mg) added to corn meal (CM) were tested. Rise in urea doses depressed gas production at each of measurement times (P<0.01). Above 50 mg of urea dose, a decrease (P<0.01) of apparent substrate degradability (ASD) was observed. In Exp. 2 nine SRU products added to CM in amounts equivalent to 50 mg (on N basis) of urea (CM + SRU), CM alone and CM added with urea (CM + U) were incubated. Gas production had the highest values for CM and the lowest for CM + U substrates (P<0.01) while for all CM + SRU mixes gas production varied between CM and CM + U values. Overall, despite a tendency for lower ADG in finishing bulls fed L diets, no detrimental effects neither on slaughter traits nor on in vitro rumen fermentation were detected. High moisture cereal grains treated with urea might be an opportunity to safety include urea in fattening diets, given their slow releasing properties and their capacity to improve microbial N synthesis found in vitro. Finally, a new approach to evaluate a variety of SRU products was suggested for consideration.Ingles

REGIONAL PECULIARITIES OF UNDERSTANDING PROFESSIONAL AND PERSONAL WELL-BEING BY NORTHERN TEACHERS AND ARCTIC TERRITORIES OF THE REPUBLIC OF SAKHA (YAKUTIA)

In the period of socio-economic transformation of the study of regional peculiarities of understanding personal and professional wellbeing of teachers in the North and Arctic territories of the Republic of Sakha (Yakutia) are particularly pertinent given with the increase of dissatisfaction with the social and economic situation of young teachers, a reluctance to carry out their professional activities in remote territorial units of the Republic of Sakha (Yakutia). In modern conditions the welfare of an individual depends not only on the environment, material security, and mental and physical health, but also on the subjective understanding of the professional and personal welfare of teachers.Analysis of domestic and foreign scientific research allows us to note that among some of the main methodological issues of research of a phenomenon well-being is the issue of the understanding of the professional and personal well-being. However, it should be noted that the problem of psychological and pedagogical support of professional and personal well-being is complex and not well understood.Thus, the study of qualitative changes in the Outlook and attitude of teachers in the North and the Arctic gives you a holistic awareness of the impact on human reality transformation processes, and identifying qualitative changes in the personality, allowing to go deeper into issues of professional personal growth in the conditions of modernization of education, contributes effectively to determine strategic goals for professional and personal development pedagogical in terms of additional professional development

Genotype C/C 13910 of the Lactase Gene as a Risk Factor for the Formation of Insulin-Resistant Obesity in Children

Introduction: To reduce the risk of insulin resistance in obesity in children with lactase gene genotypes, we studied the factors that stimulate the chronic inflammatory process. Material and methods: 109 children 6–18 years of age were investigated. The main group (n = 56) was presented by children with signs of insulin-resistant obesity according to the criteria of the European Society of Endocrinology and the Pediatric Endocrine Society. The control group (n = 53) included obese children without insulin resistance. A comprehensive clinical examination, food diary analysis, genotyping of the lactase gene by means of the polymerase chain reaction, the Immunochemical Test Method with Electrochemiluminescent Detection of basal insulinemia, Hydrogen breath test with lactose load, sequential analysis, ROC analysis were carried out. Results: Clinical manifestations of lactose maldigestion in a child increased the risk of possible insulin resistance (prognostic coefficient (PC +2.6), as well as the presence of the lactase C/C 13910 gene genotype (PC +5.8) did. The genotype C/T 13910 in children had a protective effect on the risk of obesity (PC −2.9). The lowest risk of insulin-resistant obesity in observed among children with the genotype T/T 13910 (PC −12). Conclusion: The presence of the C/C 13910 genotype of the lactase gene is the main factor formation of insulin resistance in children’s obesity. What is known? The genotype C/C 13910 of the lactase gene as a risk factor for the chronic inflammatory process in the body. What is New? Genotype C/C 13910 of the lactase gene as a risk factor for insulin-resistant obesity in children

Foraminiferal response to environmental changes in Kiel Fjord, SW Baltic Sea

The living benthic foraminiferal assemblages in Kiel Fjord (SW Baltic Sea) were investigated in the years 2005 and 2006. The faunal studies were accomplished by geochemical analyses of surface sediments. In general, sediment pollution by copper, zinc, tin and lead is assessed as moderate in comparison with levels reported from other areas of the Baltic Sea. However, the inner Kiel Fjord is still exposed to a high load of metals and organic matter due to enhanced accumulation of fine-grained sediments in conjunction with potential pollution sources as shipyards, harbours and intensive traffic. The results of our survey show that the dominant environmental forcing of benthic foraminifera is nutrients availability coupled with human impact. A comparison with faunal data from the 1960s reveals apparent changes in species composition and population densities. The stress-tolerant species Ammonia beccarii invaded Kiel Fjord. Ammotium cassis had disappeared that reflects apparently the changes in salinity over the last 10 years. These changes in foraminiferal community and a significant increase of test abnormalities indicate an intensified environmental stress since the 1960s

Der Abdruck von anthropogener Aktivität gegen natürliche Variabilität in den Förden der Kieler Bucht: abgeleitet von Sedimenten

The fjords of Kiel Bight have been inhabited for centuries and thus exposed to long-term anthropogenic influence. The fjords have restricted water exchange as reflected in periodical hypoxia. Overall, the fjords have a high buffer capacity accumulating organic matter and metals in sediments. The sediments contribute to the supply of recycled nutrients for phytoplankton, but they also may be a source of toxic compounds for benthic organisms. The deoxygenation of sediments leads to a diminution of the benthic fauna and a breakdown of the food chain. Therefore, the sediments reflect the state of the local marine system and present a valuable tool for the assessment of the environment, at present time and for the past. The objective of this study was to determine whether anthropogenic activity over the last century has left the traces in the sediments of Kiel and Flensburg Fjords where sewage discharge, shipyards, and harbours are of major importance. Further questions addressed were how the anthropogenic impact superimposes over the natural variations in Kiel and Flensburg Fjords, and what the main factors controlling the accumulation of pollutants are. To investigate these questions, surface and core sediments were analysed to recover the spatial and temporal distribution and accumulation of organic matter and trace metals in the fjords. This study revealed that the type of sediments and depositional regime are the main controls of organic matter and trace metals distribution in the fjords. Secondary factors are the gradient of primary productivity, from the inner to the outer fjord, as well as oxygenation of near-bottom water and sediments. Anthropogenic influences appear to be less significant than these factors. The accumulation of organic matter and trace metals occurs in the inner areas of the fjords. The reasons for that is the depositional regime in the inner fjords where the most intense anthropogenic discharge occurs. Anthropogenic activity does not affect the outer fjords. The only source of exception is the influence of coastal protection measures on cliff erosion and the sediment supply in depositional areas. In general, the conditions in the fjords are mesothrophic to slightly eutrophic, except for the highly eutrophied innermost Flensburg Fjord. The remediation of the fjords after the cessation of enhanced nutrient input takes more than several decades. Anoxic conditions promote denitrification, which favours the loss of nitrogen, but the input of nutrients remains high because of redeposition and resuspension of sediments under the shallow water depth. High concentrations of metals, such as copper and zinc are associated with zones of sediment accumulation in the inner fjords. Only tin, derived from antifouling paints, exhibits extremely high concentrations and only in harbours. Concentrations of lead in the sediments had decreased during the last decades due to the ban on gasoline lead additives. The enrichment of metals and organic matter for the last 70 years in a core from the outer Kiel Fjord is not clearly apparent due to changes in sedimentation rate and the observed upward coarsening of the sediments. Elevated fluxes of trace metals fell during the 1930s, when the harbours and shipyards flourished in Kiel Fjord. An increase of sewage discharges in the 1940-1970s is recorded in the core as the accumulation of organic carbon and nitrogen. The downcore distribution of redox-sensitive metals showed that no drastic changes in the oxygenation of near bottom water and sediments have occurred in the outer Kiel Fjord, in contrast to the inner fjord. In spite of expanding anthropogenic activity, its influence is not so pronounced as originally expected and what influence is seen is veiled by natural variability. However, anthropogenic effects are significant for the input of nutrients and acceleration of the natural eutrophication which finally lead to seasonal near-bottom anoxia.Die Förden der Kieler Bucht werden seit Jahrhunderten bewohnt und durch die Menschen langfristig beeinflusst. Der eingeschränkte Wasseraustausch der Förden mit der Kieler Bucht verursacht regelmäßigen Sauerstoffmangel. Die Förden sind wichtige Puffersysteme und akkumulieren organische und anorganische Verbindungen in den Sedimenten. Die Sedimente setzen wiederum Nährstoffe für das Phytoplankton durch den Abbau der organischen Substanz and außerdem Schadstoffe frei, die die Bodenfauna beeinträchtigen. Die Sauerstoffzehrung in den Sedimenten kann zur Abnahme der Bodenfauna führen und die schließlich Nahrungskette zerstören. Dadurch können die Sedimente den Zustand der ganzen Ökosysteme widerspiegeln, und sind sie deshalb gute Indikatoren des Ökosystems. Das Ziel dieser Arbeit ist zu prüfen, ob die anthropogen Aktivität während der letzte Jahrhunderte ihre Spüren in den Sedimenten der Kieler and Flensburger Förde hinterlassen hat, besonders weil die Abwässer, Werften und der Havenbetrieb dort von wichtiger Bedeutung sind. Die weitere Frage ist, wie sich der anthropogene Einfluss und die natürlichen Variationen überlagern, und welche Faktoren die räumliche und zeitliche Verteilung und Akkumulation von organischen Stoffen und Spurenmetallen kontrollieren. Die Ergebnisse dieser Untersuchung haben gezeigt dass der Sedimenttyp und das Sedimentationsregime die Verteilung von organischen Substanz und Metallen in den Förden regulieren. Der Gradient der Primärproduktion von der Innen- zum Außenförde sowie die Sauerstoffanreicherung im bodennahen Wasser und im Sediment sind von untergeordneter Bedeutung. Die anthropogen bedingte Belastung folgt diesen Faktoren ebenfalls. Die Akkumulation der organischen Substanzen und Spurenmetalle tritt in den innern Abschnitten der Förden auf, wo die Sedimentation vornehmlich stattfindet, und die anthropogene Belastung konzentriert ist. Die anthropogene Aktivität wirkt auf die Außenförden nicht in diesem Maße ein. Die einzige Ausnahme sind die Küstenschutzmaßnahmen. Sie reduzieren die Kliffserosion und ändern dadurch die Zufuhr von Sedimentationsmaterial in die Ablagerungsräume. Die Stoffumsatz charakterisiert die Förden als mesotroph bis leicht eutroph mit Ausnahme der stark eutrophen inneren Flensburger Förde. Die Sanierung der Förden nach der Reduktion der Nährstoffbelastung braucht voraussichtlich noch mehrere Jahrzehnte. Der Sauerstoffmangel fördert die Denitrifizierung und den Stickstoffverlust, aber die Nährstoffzufuhr ist immer noch hoch wegen der Umlagerung aus den geringen Wassertiefen. Erhöhte Spurenmetallkonzentrationen von Kupfer und Zink sind mit den Sedimentationsräumen in der Innenförden verbunden. Zinn, das von den Antifoulingfarben herstammt ist, führt zu überaus hohe Gehalten in den Hafensedimenten. Dagegen haben die Bleigehalte in letzen Dekaden abgenommen, vor allem wegen des Verbots von Blei-Additiven in Benzin. Die Anreicherung von Spurenmetallen und organischer Substanz während der letzten 70 Jahre ist in einem Kern aus der äußeren Kieler Förde nicht eindeutig wegen der Schwankungen in der Sedimentationsrate und einem deutlichen Trend zur Sedimentvergröberung in jüngster Zeit. Die erhöhten Spurmetallenflüsse während der dreißiger Jahre fielen in eine Zeit, als der Hafen und Schiffbau florierten. Der Anstieg der Abwässerbelastung zwischen 1940 und 1970 ist ganz deutlich in der Sedimentären Überlieferung an akkumulierte organischen Kohlenstoff und Stickstoff zu sehen. Die Verteilung von redoxsensitiven Metallen im Kern hat gezeigt dass es zu keinem langzeitigen Sauerstoffdefizit in der äußeren Kieler Förde während der letzten Jahrhunderte gekommen ist, im Gegensatz zur Innenförde. Obwohl die anthropogene Aktivität zugenommen hat, ist der Einfluss des Menschen nicht ausgeprägt und wird durch die natürliche Variabilität in den Förden verschleiert. Nur die Nährstoffbelastung, die zu einer Verstärkung der natürlichen Eutrophierung führt, ist ein schwerwiegender anthropogener Effekt in der Kieler und Flensburger Förde

Ensuring control of students' knowledge in distance learning

Ensuring adequate forms and methods of control of students' knowledge during distance learning is an urgent problem in the context of the Covid-19 pandemic, which is due to the need to involve innovative information technologies in the management of the educational process. The article on the basis of literature data presents the main functions and didactic principles of knowledge control in terms of distance learning, lists the important components of successful organization of the pedagogical process and components of the Learning Management System. At the same time, the authors of the article focus on ensuring the quality of distance learning emphasizes the effectiveness of information technology used and pedagogical skills

Risk of metabolically unhealthy obesity in children associated with lactase and MCM6 genes

Lactase deficiency associated with single nucleotide variants (SNVs) of the lactase (LCT) and minichromosome maintenance complex component 6 (MCM6) genes is the trigger that initiates meta-inflammation. Aim: to study the role of SNV LCT, MCM6 to the development of in metabolically unhealthy obesity (MUO) in children. Materials and methods. 42 obese children aged 6-18 years old were examined using whole genome sequencing (CeGat)

Role of genetic modification of the PNPLA3 gene in predicting metabolically unhealthy obesity and metabolic associated fatty liver disease in children

Introduction and aim. Single nucleotide variants (SNV) of the patatin‐like phospholipase domain‐containing protein 3 (PNPLA3) gene play an important role in hepatic lipid remodeling and lipogenesis de novo, which is associated with the development of metabolically unhealthy obesity (MUO) and metabolic associated fatty liver disease (MAFLD). The aim of the study was to define the contribution of SNV PNPLA3 gene to the development of MUO, complicated by MAFLD in children. Material and methods. 200 obese children aged 6-18 years were examined. The main group (n=118) was represented by children with MUO. The control group (n=82) consolidated of children with metabolically healthy obesity (MHO). Whole genome sequencing (CeGat) was performed in 31 children of the main and 21 children of the control group. Results. Among obese children, 14 variants of SNV PNPLA3 (rs139051, rs34179073, rs2294918, rs139047, rs779127153, rs2076212, rs738409, rs738408, rs4823173, rs2072906, rs2076213, rs141106484, rs138736228) were identified, including SNV PNPLA3 g.44322818, not described in the dbSNP core database. The role of the following SNV PNPLA3 genotypes in the development of MUO complicated by MAFLD was revealed: rs738409 C/G (Relative risk (RR)=1.71); rs738408 C/T (RR=1.71); rs4823173 G/A (RR=1.57); rs2072906 A/G (RR=1.57) with Sensitivity (Se)=0.63 and Specificity (Sp)=0.72. Conclusion. The contribution to the development of MUO complicated by MAFLD in children is made by the linked association of genotypes: rs738409 C/G, rs738408 C/T, rs4823173 G/A and rs2072906 A/G out of 14 PNPLA3 SNVs diagnosed by us

Association of genetic variants of the Fat Mass and Obesity (FTO) gene and obesity in children

Introduction and Objectives: Single nucleotide variants (SNVs) of the gene associated with fat mass and obesity (FTO) make a significant contribution to the violation of energy metabolism and the development of obesity. Study the associations between SNVs of the FTO gene and the development of metabolic disorders in children with obesity. Methods: 252 obese children aged between six and 18 were examined. The main group (n = 152) represented children with metabolically unhealthy obesity (MUO). The control group (n = 100) consisted of children with metabolically healthy obesity (MHO). Whole genome sequencing (CeGat, Germany) was performed in 31 children from the main group and 21 children from the control group. Results: The association with the development of obesity is higher for the A allele rs2287142 (t = 2.29) and the T allele SNV rs17823223 (t = 6.34) compared to healthy individuals. Serum IL-6 levels in individuals with MHO depend on SNV rs2287142 (r = 0.73). The A allele of SNV rs1080312 is associated with basal hyperglycemia (r = 0.43) and impaired carbohydrate tolerance (r = 0.33), but negatively correlates with low serum cholesterol and low-density lipoprotein cholesterol (LDL-C) (r = –0.42 and r = –0.39, respectively). The T allele of SNV rs778691805 is associated with high levels of LDL-C in blood serum (r = 0.33). The T allele of SNV rs17823223 is negatively associated with basal hyperglycemia (r = –0.51) and directly correlates with high-density lipoprotein cholesterol (r = 0.33) (p < 0.05). Discussion: In obese children, SNV rs2287142 is associated with pro-inflammatory status and SNVs rs1080312, rs17823223, and rs778691805 of the FTO gene are associated with metabolic markers