Determination of cholesterol in Italian chicken eggs

Transgenerational effects of triazole fungicides on gene expression and egg compounds in non-exposed offspring: A case study using Red-Legged Partridges (Alectoris rufa)

Triazole fungicides are widely used to treat cereal seeds before sowing. Granivorous birds like the Red-legged Partridge (Alectoris rufa) have high exposure risk because they ingest treated seeds that remain on the field surface. As triazole fungicides can act as endocrine disruptors, affecting sterol synthesis and reproduction in birds several months after exposure, we hypothesized that these effects could also impact subsequent generations of exposed birds. To test this hypothesis, we exposed adult partridges (F0) to seeds treated at commercial doses with four different formulations containing triazoles as active ingredients (flutriafol, prothioconazole, tebuconazole, and a mixture of the latter two), simulating field exposure during late autumn sowing. During the subsequent reproductive season, two to four months after exposure, we examined compound allocation of steroid hormones, cholesterol, vitamins, and carotenoids in eggs laid by exposed birds (F1), as well as the expression of genes encoding enzymes involved in sterol biosynthesis in one-day-old chicks of this F1. One year later, F1 animals were paired again to investigate the expression of the same genes in the F2 chicks. We found changes in the expression of some genes for all treatments and both generations. Additionally, we observed an increase in estrone levels in eggs from partridges treated with flutriafol compared to controls, a decrease in tocopherol levels in partridges exposed to the mixture of tebuconazole and prothioconazole, and an increase in retinol levels in partridges exposed to prothioconazole. Despite sample size limitations, this study provides novel insights into the mechanisms of action of the previously observed effects of triazole fungicide-treated seeds on avian reproduction with evidence that the effects can persist beyond the exposure windows, affecting unexposed offspring of partridges fed with treated seeds. The results highlight the importance of considering long-term chronic effects when assessing pesticide risks to wild birds.

How ICP-OES changed the face of trace element analysis: Review of the global application landscape

The 50th anniversary of Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) will be observed in 2024. ICP-OES was first commercially available in 1974, and since then, it has become one of the most widely used analytical techniques in the world. ICP-OES is a powerful tool for the determination of trace and ultratrace elemental concentrations in a wide variety of samples specifically for multielement analysis. It is used in a wide range of applications, including environmental monitoring, food analysis, and medical diagnostics. This review aims to explore recent applications of ICP-OES in areas such as food analysis, microplastics, materials, dietary supplements, human tissue, and bodily fluids. The utilization of ICP-OES in these fields has ignited the interest of prospective ICP-OES users and inspired current practitioners, as the 50th anniversary approaches, it is of value of providing an updated review. It is important to note that this work does not seek to encompass a comprehensive review of ICP-OES, given the vast number of published results in this field. Undertaking such a comprehensive task would be a daunting challenge. Consequently, an overview of the ICP-OES instrumental technique is provided, followed by a highlighting of recent significant applications in the aforementioned fields.

Tailoring of peroxidase mimetics bifunctional nanocomposite: Dual mode electro-spectroscopic screening of cholesterol and hydrogen peroxide in real food samples and live cells

A simple and rapid screening of biomarkers in clinical and food matrices is urgently needed to diagnose cardiovascular diseases. The cholesterol (Chol) and hydrogen peroxide (H₂O₂) are critical bio-indicators, which require more inventive detection techniques to be applied to real food, and bio-samples. In this study, a robust dual sensor was developed for Chol and H₂O₂ using hybrid catalyst. Bovine serum albumin (BSA)-capped nanocatalyst was potentially catalyzed 3,3',5,5'-tetramethylbenzidine (TMB), and H₂O₂. The enzymatic nanoelectrocatalyst delivered a wide range of signaling concentrations from 250 nM to 3.0 mM and 100 nM to 10 mM, limit of detection (LOD) of 53.2 nM and 18.4 nM for Chol and H₂O₂. The cholesterol oxidase-BSA-AuNPs-metal-free organic framework (ChOx-BSA-AuNPs-MFOF) based electrode surface effectively operated in live-cells and real-food samples. The enzymatic sensor exhibits adequate recovery of real-food samples (96.96-99.44%). Finally, the proposed system is a suitable choice for the potential applications of Chol and H₂O₂ in clinical and food chemistry.

Special Issue: Analysis of the Main Classes of Lipid (Fat and Oil) Components in Food and Blood by Using HPLC and Gas Chromatographic Techniques

In many cases in science, many discoveries are made by pure chance, as happened for example to Alexander Fleming (Darvel (Scotland) 6 August 1881–London (England) 11 March, 1955) who, while observing slides under a microscope in 1922, a few weeks after putting his nasal mucus on a Petri dish, noticed that cultures of microbes had developed all over the plate, except for his secretion [...]

The Effect of Storage Duration on Some Quality Traits and Composition of Eggs from Different Housing Systems

The effect of storage time at a temperature of 8°C on the direction and dynamics of changes in quality traits of eggs was investigated in shelled table eggs obtained from different egg production systems (cage system – CS, barn system – BS, free-range system – FRS). After 7, 14 and 28 d of storage, eggs from each housing system were tested for physical characteristics and for cholesterol content and fatty acid profile in the yolk. The weight of eggs from all studied housing systems declined with storage duration. The rate of weight loss was smallest in eggs from CS (P<0.05). Storage duration influenced eggshell traits but the rate and direction of these changes did not differ among the studied housing systems. Albumen height and Haugh unit score for eggs from rearing systems under study declined during storage (P<0.05). The greatest reduction of albumen height (18.85%) after the storage period was observed for CS eggs and the lowest (13.24%) for FRS eggs (P<0.05). No effect of storage duration on yolk colour intensity was observed for eggs from all the studied housing systems (P>0.05). Albumen pH increased with storage duration in eggs from all the egg production systems (P<0.05). The increase in the yolk pH during storage was the highest in FRS eggs and the lowest in the CS eggs. The storage duration of eggs from the different housing systems did not significantly influence albumen foaming capacity but adversely affected foam stability. There was no impact of storage duration of eggs from different housing systems on cholesterol content in the yolk. Eggs obtained from the different housing systems showed diverse fatty acid profiles in the yolk but this parameter did not significantly change during storage (P>0.05).

Compositional Features and Nutritional Value of Pig Brain: Potential and Challenges as a Sustainable Source of Nutrients

The goal of this study was to establish the nutritional value and compositional properties of the brains of crossbred pigs (Landrace-Large white-Duroc (LLD)), in order to realize the zero-waste concept and increase the use of by-products in the sustainable meat industry. Fat (9.25% fresh weight (fw)) and protein (7.25% fw) were the principal dry matters of pig brain, followed by carbohydrate and ash. Phospholipid and cholesterol had a 3:1 ratio. Pig brain had a red tone (L* = 63.88, a* = 5.60, and b* = 15.43) and a high iron content (66 mg/kg) due to a total heme protein concentration of 1.31 g/100 g fw. The most prevalent macro-element was phosphorus (14 g/kg), followed by potassium, sodium, calcium, and magnesium. Zinc, copper, and manganese were among the other trace elements discovered. The most prevalent nitrogenous constituents were alkali-soluble protein, followed by water-soluble protein, stromal protein, salt-soluble protein, and non-protein nitrogen. Essential amino acids were abundant in pig brain (44% of total amino acids), particularly leucine (28.57 mg/g protein), threonine, valine, and lysine. The total lipid, neutral, and polar lipid fractions of the pig brain had different fatty acid compositions. The largest amount was observed in saturated fatty acids (SFA), followed by monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). Stearic acid and palmitic acid were the most common SFA. Oleic acid was the most prevalent MUFA, while docosahexaenoic acid was the most common PUFA. Thus, the pig brain can be used in food formulations as a source of nutrients.

Cholesterol oxidase immobilized inulin based nanocomposite as the sensing material for cholesterol in biological and food samples

In the present study, inulin based nanocomposite viz., TiO₂-MWCNT@Inulin was prepared by embedding Inulin (a biopolymer extracted from Allium sativum L.) with TiO₂ and MWCNTs. The morphology of the prepared nanocomposite was characterized by High Resolution transmission electron microscopy (HRTEM). Cholesterol oxidase (ChOx) enzyme was then immobilized into the nanocomposite and the immobilization was examined by UV-vis and FT-IR spectral studies. The ChOx immobilized nanocomposite was integrated into carbon paste (CP) matrix to prepare the working electrode for the sensing of cholesterol. Electrochemical characterization of the modified CP/TiO₂-MWCNT@Inulin/ChOx electrode was done by cyclic voltammetric (CV) and electrochemical impedance spectroscopic (EIS) studies. Differential pulse voltammetric (DPV) studies were carried out to determine the concentration of cholesterol at the interface of the newly fabricated electrode. The fabricated electrode demonstrated a linear range from 83 μM to 14.28 mM, low limit of detection (35 μM), good sensitivity (21.26 μA mM^-1  cm^-2), low K_m (0.49 mM), high stability (120 days) and good selectivity. The presence of Inulin biopolymer played a vital role in attaching ChOx enzyme firmly to the nanocomposite thereby enhancing the stability and electron transfer efficiency of the electrode. The analysis of product that was formed within the electrochemical cell during the electrochemical oxidation of cholesterol was performed by using sodium nitroprusside. This resulted in a deep purple coloured solution which suggested the electrochemical conversion of cholesterol to cholestenone. The practical applicability of the fabricated electrode was also assessed by the determination of cholesterol in spiked blood serum and milk samples.

A Validated Method for Cholesterol Determination in Turkey Meat Products Using Relative Response Factors

The objective of this study was to develop a precise and accurate method to quantify cholesterol in turkey meat products using relative response factors, based on a modification of a previously published method for plant sterols determination. Validation was performed using neat solutions to determine linearity, precision, and accuracy. The method was linear in the concentration range considered (1–20 µg/mL, r² ≥ 0.991). Precision and accuracy were within the acceptability guidelines of the U.S. Food and Drug Administration (FDA) for method validation (<20% relative standard deviation (RSD) at the lower limit of quantification (LLOQ) and <15% RSD for other standards). Turkey meat was spiked with cholesterol at two levels (low = 3 µg/mL and high = 18 µg/mL), either before or after saponification, to establish the recovery and matrix effects. Recovery ranged from 94% to 105%, with a mean value of 105% at the low spike level and 95% at the high spike level. No significant matrix effects were found (90% to 112% recovery). This method is reliable for the quantification of cholesterol in turkey meat products in the range 0.4–8 mg/g.

Linseed Essential Oil - Source of Lipids as Active Ingredients for Pharmaceuticals and Nutraceuticals

Linseed - also known as flaxseed - is known for its beneficial effects on animal health attributed to its composition. Linseed comprises linoleic and α-linolenic fatty acids, various dietary fibers and lignans, which are beneficial to health because they reduce the risk of cardiovascular diseases, as well as cancer, decreasing the levels of cholesterol and relaxing the smooth muscle cells in arteries increasing the blood flow. Essential fatty acids from flax participate in several metabolic processes of the cell, not only as structuring components of the cell membrane but also as storage lipids. Flax, being considered a functional food, can be consumed in a variety of ways, including seeds, oil or flour, contributing to basic nutrition. Several formulations containing flax are available on the market in the form of e.g. capsules and microencapsulated powders having potential as nutraceuticals. This paper revises the different lipid classes found in flaxseeds and their genomics. It also discusses the beneficial effects of flax and flaxseed oil and their biological advantages as ingredients in pharmaceuticals and in nutraceuticals products.

Effects of Ginger Extract on Laying Performance, Egg Quality, and Antioxidant Status of Laying Hens

Simple Summary

The application of in-feed antibiotic growth promoters was banned in many countries due to their negative effects, and several kinds of feed additives were widely investigated as antibiotic alternatives, in which natural plant-derived products received much attention due to their environmentally friendly properties and numerous biological activities. Ginger (Zingiber officinale Roscoe), a widely used herbal medicine and spice, was proven to have potential as an antibiotic alternative in poultry feed, but there is little literature on the efficacy of ginger extract (GE), which has concentrated bioactive compounds with high bioavailability. Our results showed that dietary GE supplementation increased egg weight, improved egg quality, and reduced the yolk cholesterol content of laying hens. Decreased serum activities of alanine transaminase and aspartate transaminase and improved antioxidant status were observed in the GE group. Our study demonstrated the potential benefits of GE in laying hens.

Abstract

The objective of this study was to investigate the effects of ginger extract (GE) as a dietary supplement for laying hens. A total of 40-week-old 288 Hyline Brown laying hens were randomly divided into two groups with six replicates, and fed a basal diet with or without 100 g/t GE for eight weeks. Dietary GE supplementation increased egg weight, albumin height, and Haugh unit of eggs, and decreased yolk cholesterol content and activities of alanine transaminase and aspartate transaminase in serum at eight weeks. Moreover, GE resulted in higher total superoxide dismutase (T-SOD) activity and lower malondialdehyde (MDA) content in yolk at four and eight weeks and in serum. It was concluded that GE was effective in increasing egg weight and improving the egg quality and antioxidant status of laying hens.

Effect of a Combination of Fenugreek Seeds, Linseeds, Garlic and Copper Sulfate on Laying Hens Performances, Egg Physical and Chemical Qualities

Several investigations have suggested that fenugreek seeds may have a hypocholesterolemic activity, and thus be efficient in the treatment of egg yolk cholesterol. The objective of the current study was to evaluate the effect of dietary incorporation of 3% of fenugreek seed combined with 3% of linseed, 1% of garlic paste, and 0.078% of copper sulfate on laying performance, egg quality and lipids profile. Forty four, 41 weeks old, Novogen White laying hens received for 42 days 100 g/d of basal diet (control) or experimental diet (CFSGLSCS). With the exception of egg weight, which showed a significant increase for hens fed on CFSGLSCS with 57.99 g compared to 56.34 g for the control group, egg production (90.84% for control compared to 87.89% for experimental diet), egg mass (50.95 g/d for control compared to 50.87 g/d for CFSGLSCS), feed efficiency (1.94 for control compared to 1.98 for CFSGLSCS) were not affected by dietary treatments. The addition of CFSGLSCS reduced (p < 0.05) egg yolk cholesterol by 5.4% and blood cholesterol from 158.42 mg/dL to 122.82 mg/dL for control and CFSGLSCS, respectively. The dietary addition of CFSGLSCS increased (p < 0.05) total lipids from 4.5 g/egg to 5.23 g/egg and didn’t affect (p > 0.05) yolk triglycerides.

Effect of Dietary Incorporation of Linseed Alone or Together with Tomato-Red Pepper Mix on Laying Hens' Egg Yolk Fatty Acids Profile and Health Lipid Indexes

This study evaluated the effect of linseed incorporation in laying hens’ feed (alone or along with a tomato-red pepper mix) on laying hens’ egg yolk fatty acids profile, as well as on their atherogenic (IA) and thrombogenic (IT) health lipid indexes, and the ratio between the hypocholesterolemic and hypercholesterolemic fatty acids (HH). Sixty 27 weeks-old Novogen White laying hens were divided into three groups and given 100 g/hen/day of a standard diet (Control, C) containing 4.5% of ground linseed (Linseed diet, L), containing 1% of dried tomato paste and 1% sweet red pepper (Lineseeds-Tomato-Pepper, LTP). The linseed dietary inclusion significantly reduced the egg yolk content of palmitic acid from 25.41% (C) to 23.43% (L) and that of stearic acid from 14.75% (C) to 12.52% (L). Feeding 4.5% ground linseed did not affect the egg yolk content of α-Linolenic acid but significantly increased the egg yolk concentration of eicosapentaenoic acid (EPA) from 0.011% (C) to 0.047% (L) and that of docosahexaenoic acid (DHA) from 1.94% (C) to 2.73% (L). The IA and the HH were not affected (p > 0.05) by the dietary addition of linseed, whereas the IT decreased (p < 0.05) from 1.16 (C) to 0.86 (L). Adding tomato-sweet red pepper mix to the linseed-supplemented feed did not affect the measured parameters as compared to the linseed dietary treatment.

Liquid Chromatography Analysis of Common Nutritional Components, in Feed and Food

Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review focused on the common obstacles and peculiarities that each analyte offers (during the sample treatment or the chromatographic separation) throughout the implementation of said methods. A brief description of the techniques which we considered to be more pertinent, commonly used to assay such analytes is provided, including approaches using commonly available detectors (especially in starter labs) as well as mass detection. This manuscript consists of three sections: feed analysis (as the start of the food chain); food destined for human consumption determinations (the end of the food chain); and finally, assays shared by either matrices or laboratories. Analytes discussed consist of both those considered undesirable substances, contaminants, additives, and those related to nutritional quality. Our review is comprised of the examination of polyphenols, capsaicinoids, theobromine and caffeine, cholesterol, mycotoxins, antibiotics, amino acids, triphenylmethane dyes, nitrates/nitrites, ethanol soluble carbohydrates/sugars, organic acids, carotenoids, hydro and liposoluble vitamins. All analytes are currently assayed in our laboratories.

Determination of Egg Number Added to Special Pasta by Means of Cholesterol Contained in Extracted Fat Using GC-FID

Pasta with eggs added (generally termed “special pasta” for Italian legislation) is made by adding no less than 4 eggs without shells (or no less than 200 g of liquid or lyophilized egg product) per kilogram of semolina, as provided by law. In this work, to determine the final content of eggs added to dough, an analytical procedure was developed for the rapid analysis of the cholesterol content in the finished pastas. The proposed procedure was simpler, faster, and more accurate than that of official methods of analysis based on the gravimetric determination of sterols. Moreover, the determination of the quality of fat content in the special pasta (egg pasta in this case) allowed the evaluation of its origin, avoiding possible fraud resulting from the addition of foreign fat as an alternative to fat derived from eggs. In this new gas chromatographic procedure, the internal standard squalene for the quantification of cholesterol was used because a more polar GC capillary column was used (RTX 65 TG-HT) for the separation of sterols, rather than 5% phenyl methylsilicone. The ratio between cholesterol and squalene allowed for the determination of the number of eggs added, while from analysis of the same gas chromatogram, it was also possible to evaluate the composition of triglycerides in the fat contained in the pasta, allowing discrimination of foreign fats with respect to fats contained in eggs and therefore avoiding adulteration of pasta. The same analytical procedure was applied to the determination of cholesterol content in lyophilized yolk.

Chemical and Nutritional Characterization of Seed Oil from Cucurbita maxima L. (var. Berrettina) Pumpkin

Pumpkin (Cucurbita spp.) has received considerable attention in recent years because of the nutritional and health-protective value of seed oil. The nutritional composition of pumpkin native to central Italy, locally known as “Berrettina” (Cucurbita maxima L.), was evaluated. In particular, the lipid fraction of seed oil was characterized, and the triacylglycerol (TAG) was thoroughly studied by using a stereospecific procedure to obtain the intrapositional fatty acid composition of the three sn-positions of the glycerol backbone of TAG. Moreover, alkaline hydrolysis was carried out to study the main components of the unsaponifiable fraction, i.e., sterols and alcohols. It was observed that monounsaturated fatty acids and polyunsaturated fatty acids were the most abundant (41.7% and 37.2%, respectively) in Berrettina pumpkin seed oil, with high content of oleic and linoleic acid (41.4% and 37.0%, respectively). The main sterols of Berrettina pumpkin seed oil were Δ^7,22,25-stigmastatrienol, Δ^7,25-stigmastadienol, and spinasterol; with regard to the alcoholic fraction, triterpenic compounds were more abundant than aliphatic compounds (63.2% vs. 36.8%). The obtained data are useful to evaluate pumpkin seed oil from a nutritional point of view. The oil obtained from the seed could be used as a preservative and as a functional ingredient in different areas, e.g., cosmetics, foods, and nutraceuticals.

Italian Opuntia ficus-indica Cladodes as Rich Source of Bioactive Compounds with Health-Promoting Properties

Natural by-products, especially phenolic compounds, are in great demand by the nutra-pharmaceutical and biomedical industries. An analytical study was performed to investigate, for the first time, the presence of antioxidant constituents and the corresponding in vitro antioxidant activity in the extract of cladodes from Ficodindia di San Cono (Opuntia ficus-indica) protected designation of origin (PDO). The cladode extracts were analysed for target determination of selected constituents, i.e., β-polysaccharides and total phenolic content. Moreover, the antioxidant activity of hydro-alcoholic extracts was assessed by means of two different methods: α, α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging method and ferric reducing antioxidant power (FRAP) assay. An untargeted UHPLC-ESI-QTOF-MS profiling approach was used to depict the phenolic profile of hydro-alcoholic cladode extracts. Interestingly, over 2 g/kg of polyphenols were detected in this matrix, and these compounds were mainly responsible for the antioxidant properties, as shown by the strong correlation between phenolic classes and antioxidant scores. Finally, this study provides basic information on the presence of bioactive compounds and in vitro antioxidant activities in cladode extracts from cactus that might recommend their novel applications at the industrial level in the field of nutraceutical products.

Egg Consumption and Risk of Metabolic Syndrome in Korean Adults: Results from the Health Examinees Study

Metabolic syndrome (MetS) is defined as a cluster of metabolic alterations such as abdominal obesity, dyslipidemias, elevated fasting glucose, and hypertension. Studies on the association between egg consumption and MetS are limited and inconsistent. A cross-sectional analysis was conducted to examine the association of egg consumption with MetS among Korean adults aged 40–69 years. A total of 130,420 subjects (43,682 men and 86,738 women) from the Health Examinees Study were selected for the final analysis. Egg consumption was estimated using a validated 106-item food frequency questionnaire. MetS was defined using the National Cholesterol Education Program, Adult Treatment Panel III. Logistic regression analyses were performed to identify the association of egg consumption with MetS via odds ratios (ORs) and 95% confidence intervals (CIs) after adjusting for potential variables. Among 130,420 subjects, 34,039 (26.1%) people had MetS. Consumption of more than 7 eggs/week was associated with a lower odds of MetS risk compared to those who consumed less than one egg/week in women (OR: 0.77, 95%CI: 0.70–0.84, p trend < 0.0001). Higher egg consumption was inversely associated with the MetS components: elevated waist circumference (OR: 0.80, 0.75–0.86), elevated triglyceride (OR: 0.78, 0.72–0.85), reduced high-density lipoprotein cholesterol (HDL-C) (OR: 0.82, 0.77–0.88), elevated blood pressure (OR: 0.86, 0.80–0.92), and elevated fasting glucose (OR: 0.94, 0.83–0.99) in women; reduced HDL-C (OR: 0.89, 0.80–1.00) in men. Our results suggest that higher egg consumption may be associated with a reduction in the odds for MetS and all five metabolic components in women, and the risk of reduced HDL-C in men.

Bioactive Egg Components and Inflammation

Inflammation is a normal acute response of the immune system to pathogens and tissue injury. However, chronic inflammation is known to play a significant role in the pathophysiology of numerous chronic diseases, such as cardiovascular disease, type 2 diabetes mellitus, and cancer. Thus, the impact of dietary factors on inflammation may provide key insight into mitigating chronic disease risk. Eggs are recognized as a functional food that contain a variety of bioactive compounds that can influence pro- and anti-inflammatory pathways. Interestingly, the effects of egg consumption on inflammation varies across different populations, including those that are classified as healthy, overweight, metabolic syndrome, and type 2 diabetic. The following review will discuss the pro- and anti-inflammatory properties of egg components, with a focus on egg phospholipids, cholesterol, the carotenoids lutein and zeaxanthin, and bioactive proteins. The effects of egg consumption of inflammation across human populations will additionally be presented. Together, these findings have implications for population-specific dietary recommendations and chronic disease risk.

DART mass spectrometry for rapid screening and quantitative determination of cholesterol in egg pasta

To ensure that egg-containing products, such as dried eggs and egg pasta, conform to the technological and legislative requirements for egg content, methods are needed to determine the amount of cholesterol in such products. The conventional approach, direct saponification and hexane extraction followed by cholesterol determination by gas chromatography coupled to a flame ionization detector, is very time consuming. Therefore, we developed a rapid method on the basis of direct analysis in real time coupled to time-of-flight mass spectrometry. Samples were prepared simply by solvent extraction followed by extract filtration. The optimization of certain parameters, including the solvent used and direct analysis in real time ionization gas temperature, had a pronounced effect on the intensities of the produced ions, in particular, the molecular and dehydrated ions of cholesterol and its deuterated analog, cholesterol 2,2,3,4,4,6-d(6) which was used as an internal standard. For the developed method, limits of detection and quantification were 0.03 and 0.05 mg g(-1) respectively. The results of the real samples were compared with those obtained using the conventional approach [limit of detection = 0.002 mg g(-1) and limit of quantification = 0.05 mg g(-1)], and it was found that, although the results obtained using the conventional approach were more accurate, our developed method is much simpler and faster, where the time was dramatically reduced by 87% for executing a screening analysis.

Applying the principles of welfare and quality of production in the organic farm of the laying hens

European Union  banned with Council Directive No. 74/1999/EC use of the conventional battery cages for laying hens in European Union with effect from January 1, 2012. By this time much attention was paid to the assessment of laying hens welfare in the modified breeding system,namely from aspect of behavior and expression fyziological stress. At present are used the enriched cages,   which device is defined by the Code of laying hens living conditions. Quantification of intensity and sequence of the events in different behaviour and a time regime can contribute to knowledge of time spending of the laying hens  in the breeding area and to determining of prioritizing their behavior.The aim of our research was assessment an application of principles laying hens welfare in the farm, their production and egg quality. An object of investigation was ecological farm of laying hens. In the experiment were observed thehousing conditions and nutrition of laying hens in farm, egg production, egg weight at laying hens old 42 weeks and selected indicators of chemical formation of the eggs. In the farm were reared laying hens ISA Brown, which are high-productive and the most   the most widely used in EU. The informations and data on farm, laying hen hall, breeding facility, breeding conditions, the behavior of the laying hens, nutrition, feeding and egg production were obtained by personal visit an organic farm and informations which  the farmer records and stores. The informations about the behavior of laying hens were obtained by observing and comparing with the knowledge and data of the Slovak Government regulation on December 11, 2002, which   minimum standards determine for the protection of laying hens.The informations on feed were obtained  directly from an organic farm and   feed company that followed by accordance  the minimum content of nutrients and energy in accordance with the needs of the laying hens. Egg production was monitored on the base of  collecting eggs two and several times a day, which was recorded daily on an organic farm. Chemical analyzes of samples of eggs were conducted according to the methodology for analytical laboratories (2009). In the farm were application welfare principles.  The laying hens had unlimited access to feed and water, ad libitum, free movement in the stable hall on the litter and perches. The laying hens rummaged and ashed in the free-range are of clay. In the free-range area of grassland where was a shelter, they free ranged and explorated environment. The microclimatic conditions, a construction of the perches, nests in the hall and location of the feedersand drinkers in the hall and in the free-range were solution in the accordance with the needs of improved living conditions of the laying hens. The laying hens achieved an intensity of egg-laying 84.60% in the all laying cycle. An egg weight was 62.30 g at laying hens old 42 weeks. The average dry mater contents was in the table eggs 26.21 g per 100 g of egg mass, the proteins 12.34 g per 100 g of egg mass, a fat 11.63 g per 100 g of egg mass and a cholesterol 1.27 g per 100 g of egg yolk. On the base of achivied the results, further research was recommended in the field the welfare of the laying hens intendent for the production of the table eggs.