Understanding the efficacy of organic trace minerals has been increasingly important over the past few years as a result of increased customer awareness of their benefits and the increase in the number of commercial products available to the customer. Organically bound trace minerals of interest in animal nutrition specifically include iron, zinc, manganese, copper, cobalt, and selenium. These elements have been shown to improve reproductive efficiency as measured by conception rate, alleviated calving, and reduced placenta expulsion rate. Additional benefits include improved growth performance of calves. The field trials in the period of 2005 – 2007 with Charolais breed beef cattle cows and calves verified efficacy of the premix PROTRACE G containing Fe, Zn, Cu, Mn, and Co chelates, Se-amino acid (selenomethionine), potassium iodide, and vitamins A, D3 and E. Average calving rate of experimental group cows fed diet with added premix was 20 – 30 min, placenta expulsion time - 28 – 31 min, but in control group fed only basal diet - 2 h 21 min and 1 h 30 min – 2 h 09 min (p is less than 0.05) respectively. Live weight gain of calves and heifers of the experimental group was on 35 – 39% higher (p is less than 0.05) than that in the control group.

This article presents the results of studies of the chemical composition of the fish meat while using as a feed additive zeolite of Chankanay origin. The research was conducted during 2011-2013 at the Department of Veterinary-sanitary examination and hygiene of the Kazakh National Agrarian University and at the laboratory of JSC ‘Kazakh Academy of Nutrition’ LTD ‘NUTRITEST’. The material of study was the zeolitic tuff of Chankanay deposit (Almaty region) and two-year trout Oncorhynchus mykiss. For the research we used feed by recipes of GosNIORH - 12-80. The chemical composition of fish meat was determined by a set of methods: moisture by drying at 105 °C, fats by Soxhlet, total protein by modified Kjeldahl method (ISO 937:1974), and minerals by incineration in a muffle furnace. Calorie content of meat was determined by Alexandrov’s formula: X = C - (F+A) ´ 4.1 + F ´ 9.3. Fatty acid composition of fish meat was determined by gas-liquid chromatography. Thus, the results are the indirect evidence that zeolites added to primary diet for growing fish, do not adversely impact proteolytic enzyme systems of fish, that is, have no negative effect on fish organism.

Food and drinking water are the main sources of trace and major elements. Besides the elements that are vitally essential for living organisms and human health, food may contain the traces of potentially toxic elements. Environmental site specific impact is one of the influencing factors of elemental content in plants that is important issue also for quality of food crops. Quantitative content of several trace elements (e.g., Al, As, Cd, Co, Cr, Cu, Ni, Pb, Zn) detected in food crops reveal environmental background levels as well as it can be associated with unexpected food contamination. Current study involves quantitative analysis of more than 200 root vegetable samples (onions, carrots and potatoes) grown and collected in Latvia in the harvesting season of 2010. Within this study the quantitative analysis of vegetables for 9 elements (As, Cd, Co, Cr, Cu, Ni, Pb, Se, Zn) was performed. After the wet digestion of samples, the quantitative analysis was done by using inductively coupled plasma mass spectrometry (ICP-MS). Obtained results revealed wide ranges of trace elements in root vegetables, including potentially toxic elements. Comparison of element content in edible parts of vegetables and potato peel showed that a great part of elements (e.g., As, Co, Cr, Pb) is concentrated in peel; however, some elements (e.g., Cd, Se, Zn) are taken up by plants, and therefore may contaminate food more easily. Element transfer routes and their biochemistry is a complicated issue that is affected by natural environmental factors as well as by anthropogenic activities.

Lake sediments have a broad range of elementary and organic substance content. Bottom sediments collect decaying organic debris of aquatic plants and animals mixed by water drift with mineral constituents - deposited in the bottom of the lake in anoxic conditions. Lake Alūksne is situated in Northeast Latvia and is of glacial origin. Its water and bottom sediments chemical content depends on formation conditions – influenced also by anthropogenic activities. In order to determine environmental quality for restoration purposes and sediment recovery, geochemical research is needed. This paper aims to study bottom sediments – texture, ash part, organic compounds and metals to pinpoint necessary steps that are crucial for distinguishing environmental quality of the lake through geochemistry research. Bottom sediments contain sapropel with large admixture of organic compounds and microelements that may significantly influence biota and human health if concentration exceeds natural background levels. When bottom sediments are recovered, it may improve oxygene conditions in the lake, extracted sapropel can be used as a fertilizer, therapeutic agents, supplements for farm foods. Generally, sapropel is improving the structure of agricultural soils, increasing the cation exchange capacity and serving as binding material for complexes formation; thus diminishing ecotoxicological exposure threats of heavy metals, increasing yields and albumen and protein quantity in plants cultivation products. As these sediments can be used for soil fertilizing and crop production improvement in agriculture, mechanisms of ecotoxicological impact to various soil types and agricultural plant ecology should be researched.

The present research was carried out to investigate the effects of different fertilizer treatments on grain yield and yield components of spring wheat (Triticum aestivum L.) ‘Harenda’ cultivar. The five treatments were as follows: control (standard NPK fertilization), standard NPK fertilization plus liquid NPK (10-11-11) fertilizer, standard NPK fertilization plus liquid NPK (10-11-11) fertilizer with microelements, standard NPK fertilization plus calcium micronized suspension fertilizer, and standard NPK fertilization plus Cu, Mn, Zn, Ca micronized suspension fertilizers. The field trials were conducted in 2017 at the Experimental Site of Institute of Soil Science and Plant Cultivation – State Research Institute in Puławy, Poland. Applications of calcium micronized suspension foliar fertilizer and a mixture of Cu, Mn, Zn, Ca micronized suspension fertilizers significantly increased grain yield of spring wheat, respectively by 44.5% and 38.6% in comparison with control (standard NPK fertilization). These fertilizer treatments also enhanced yield components of spring wheat. Moreover, micronized suspension fertilizers (Ca and the mixture of Cu, Mn, Zn, Ca) had a significant effect on ear number and thousand grain weight of spring wheat compared to control and NPK fertilizers. Liquid NPK and micronutrient-enriched NPK fertilizers had a significant effect on thousand grain weight compared to control.

Selenium (Se) is an essential microelement for human health; it is not synthesized in human body and cannot be substituted by any other element. Many health problems have a link with Se deficiency. People need to obtain all necessary amounts of selenium with food. Cereal products are important components of our diets and can contribute comparatively large part of the total dietary intake of Se. The wheat grains growing in Latvia contain comparatively small amount of selenium - on average 0.04 mg kgE-1. The objective of this study was to investigate the possibilities of fortifying wheat grains with microelement selenium during soaking grains in selenium containing solutions. Wheat grain was soaked in sodium selenite and sodium selenate solutions with selenium concentration from 10 to 200 mg lE-1. Sprouting activity was determined after 24, 72 and 120 hours, the influence of selenium valence in compound was observed. Comparing the influence of Se**+4 and Se**+6, it can be concluded that Se**+4 does not promote sprouting activity of wheat grains position to Se**+6 which increases sprouting activity till selenium concentration 100 mg lE-1. Uptake of selenium in grains was studied by determination of total Se using atomic absorption spectroscopy method. Linear correlation between Se concentrations in applied soaking solutions and Se concentration in grains was observed. The content of total protein did not change significantly - it varied from 13.64% in the control sample to 13.87% in the wheat sample with the highest applied selenium concentration (200 mg lE-1).

The effect of different fertilisers and storage temperature on the content of reducing sugar in potatoes of different varieties, destined for processing into chips, was investigated at the Elmininkai Research Station of the Lithuanian Institute of Agriculture during the period 2000-2001. Five potato varieties belonging to different maturity groups were investigated: early 'Goda' and 'Voke', medium early 'Lady Rosetta', medium late 'Saturna' and 'Hermes'. Potatoes of all the investigated varieties were grown in the plots with different fertilisation: 1 - manure - 40 t ha*[-1), 2 - chopped straw+one-component mineral fertilisers at the rate of N45P45K90, 3 - one-component mineral fertilisers at the rate of N90P90K180, 4 - complex mineral fertilisers with microelements at the rate of N90P90K180. It was established that reducing sugar content in potato tubers depended on the genetic properties of the variety, storage temperature and fertilisation.