Introduction. The present research featured biochemical and microstructural features of thyroid glands obtained from lambs raised on various feeds enriched with essential elements. The article focuses on iodine as the most important physiologically active microelement. Iodine participates in the synthesis of thyroid hormones, namely thyroxine and triiodothyronine, which are known to regulate metabolic processes. Iodine deficiency may impair reproductive function and cause such diseases as endemic goiter. Study objects and methods. The study involved thyroid glands from lambs of the Edilbaev breed aged seven months. The lambs were divided into four experimental groups, ten animals in each. The lambs received several feed additives. Ioddar-Zn and DAFS-25 had a balanced protein and carbohydrate content, while the mineral feed of Coretron brand contained such trace elements and minerals as iodine, selenium, and silicon. Results and discussion. The experiment made it possible to describe the microstructural profile of the thyroid glands extracted from seven-month-old lambs raised on feeds enriched with iodine and selenium. Ioddar-Zn and DAFS-25 did not harm the structure of the thyroid tissue, while causing its functional activation in some cases. The morphological parameters of the thyroid glands indicated some breed differences. The iodine concentration in the thyroid glands obtained from the experimental animals was five or six times higher than that in the control group. The content of mono- and diiodotyrosine depended on the accumulation profile of organic iodine. Conclusion. Diets enforced with DAFS-25, Ioddar-Zn, silicon, and a protein-carbohydrate complex produced no negative effect on the structure of the thyroid tissue. It fact, the diet increased the organic iodine content in the thyroid glands in the form of iodotyrosines. The gland structure revealed some cubic epithelium or follicular cells. The mass spectrometric studies confirmed the presence of covalently bound iodine in the form of mono- and diiodotyrosine. Thus, the abovementioned feed additives can be recommended for industrial use.

Properties of wide superconducting tin films in the resistive

Горлов И.Ф., доктор сельскохозяйственных наук, профессор, академик РАН 1,2 Федотова Г.В., доктор экономических наук, доцент 1,2 Сложеникина М.И., доктор биологических наук, профессор 1 Куликовский А.В., научный сотрудник 3 Мосолова Д.А., студентка 1,2 Gorlov I.F., doctor of agricultural sciences, professor, academician of RAS 1,2 Fedotova G.V., doctor of economical sciences, associate professor 1,2 Slozhenkina M.I., doctor of biological sciences, professor 1 Kulikovsky A.V., scientific researcher 3 Mosolova D.A., student Ключевые слова: рынок мяса, животноводство, говядина, питательная ценность, доходы, потребление.

Nowadays, the development of environmentally-friendly packaging materials is relevant worldwide. Biodegradable packaging materials are promising due to their safety and ability to extend shelf life of food products. This study aimed to investigate the properties of biodegradable film based on a bacterial exopolysaccharide (xanthan) with the view to extend the quality and shelf life of chilled meat products. We studied pork and carp samples packed in biodegradable film and stored at 0–2°C. Biodegradable packaging had positive effects on sensory, physicochemical, and microbiological parameters, as well as on ecological safety of the raw materials. During storage of packed chilled pork, its mass loss decreased from 2.16 to 0.21% (norm to 0.30%), and water activity reduced from 0.985 to 0.960, which had a positive effect on the microbiological resistance of pork during storage. The use of biodegradable film contributed to the preservation of quality and freshness of carp, which was confirmed by sensory and microbiological indicators. Total microbial contamination in carp packed in biodegradable film was significantly lower than that in unpacked samples, which extended its shelf life for one day compared to control. Biodegradable packaging also allowed mass loss and pH value to decrease during storage and inhibited oxidation processes in the samples under study. Free fatty acid content decreased by a factor of two, and peroxides, by 7%. Thus, biodegradable films can be effective film coatings to use in the food industry. This method of packaging not only preserves the functional and technological properties of food products, lowers their mass loss, and extends their shelf life, but also reduces costs and is environmentally friendly.

The research featured the effect of a diet fortified with essential microelements on the ruminal microbiota of young rams. Ruminal microbiota is largely responsible for feed digestibility and body functioning of cattle. The study involved the contents of the rumens and jejuna of seven-month-old rams of the Edilbaev breed, which were subjected to a biofortified diet. The diet included the Russian feed additives Yoddar-Zn and DAFS-25 represent a protein-carbohydrate complex with plant silicon. The microflora of the digestive tract was tested using the molecular genetic method of terminal restriction fragment length polymorphism (T-RFLP) sequestration. The microstructural studies of the jejunum samples exploited light microscopy. The feed additives increased the population of cellulolytic and lactate-fermenting bacteria, as well as the Prevotella sp. microbiome and bifidobacteria in the rumen samples. The data obtained revealed the effect of essential microelements on the taxonomic pattern of microorganisms and the microflora profile. The research revealed the ratio of normal, opportunistic, pathogenic, nonculturable, and transit microflora. The jejunum wall samples obtained from the experimental group that fed on Yoddar-Zn and DAFS-25 had a more distinct micropicture of mucous membrane. Their rumen microflora balance had fewer pathogenic and opportunistic microorganisms, which was also confirmed by the jejunum morphology. The feed additives DAFS-25 and Yoddar-Zn proved beneficial for ram diet and inhibited the negative effect of pathogenic treponemas on the rumen. The additives improved digestion, absorption, and assimilation of food nutrients, as well as increased the livestock yield.