The relationship between lysozyme gene polymorphism and quality changes during the storage of eggs derived from 2 commercial strains of Japanese quail

During the storage irreversible changes occur in eggs that result in a deterioration of their quality. The most significant changes affect the albumen. One of the major proteins of albumen present in egg white is lysozyme, which protects the embryo from microorganisms. This enzyme also contributes to the qualitative characteristics of albumen. It is possible that its polymorphism also affects the quality and stability of the obtained raw material that is, table eggs. Therefore, the aim of this study was to assess the potential effect of polymorphism in the lysozyme gene and protein on the quality changes during the storage of eggs derived from 2 genetic strains of Japanese quail belonging to various utility types. Eggs from selected females of laying and meat-type breeds were stored for 14 wk. During this period the egg quality traits were evaluated 10 times. DNA was isolated from each female and all exons of the lysozyme gene had been sequenced. In total, fourteen SNPs' and one 4-bp indel mutation were identified in exons and adjacent intronic sequences, among which SNP1 (1:32140723) resulted in a substitution of lysine with glutamine (Q21K). The results showed that SNP1 (strain S22), as well as the SNP2, SNP5, SNP7, SNP8, SNP10, SNP11, SNP12 and SNP13 were significantly associated with breaking strength during egg storage in both investigated Japanese quail strains. Furthermore, a 3 haplotype blocks containing nine SNPs (2, 5, 6, 7, 8, 10, 11, 12 and 13) were identified. These blocks displayed 8 distinct haplotypes that had significant association with breaking strength at all storage time points where egg quality analyses were performed. The study also revealed significant effects of breed and storage time on the egg quality traits. These results provide new insights into the genetic basis of egg quality during storage and could be incorporated into the breeding programs involving these strains.

The sex impact on the technological and chemical characteristics of meat derived from the Polish native chicken breed

The aim of the study was to evaluate the birds' sex as well as the caponisation influence on the technological traits of obtained meat, fatty acids profile as well as main chemical compounds distribution. In this study, 40 hens, roosters and green-legged partridge capons each were used (4 replications each). At 24 weeks of age, 2 birds from each replication subgroup were selected and slaughtered. During dissection analysis, pectoral and femoral muscles were sampled. Acidity, colour, tenderness, water holding capacity, drip and cooking loss were determined in the obtained material. The fatty acid profile of the meat was also determined, as well as the distribution of components in the pressed meat samples using FTIR spectroscopy. Statistically significant differences in the colour lightness index (L*) of the breast muscles were recorded, with cockerel meat being the darkest and capon meat the lightest. The greatest natural water loss was recorded in the hens' pectoral muscle; cooking loss was also the greatest in these samples. Roosters showed significantly the lowest content of monounsaturated fatty acids, at the same time the highest proportion of the n3 fatty acids group was found in capons. Irrespective of muscle, meat from roosters showed the highest susceptibility to oxidation (PI index). The variation in the chemical composition of the meat was confirmed by FTIR mapping.

Pedigree Analysis of Warmblood Horses Participating in Competitions for Young Horses

The aim of the study was to characterize the population structure and assess the genetic diversity of warmblood horses used in the show jumping discipline. Pedigree data of 1,048 horses participating in the Polish Championships for Young Horses were analyzed. The pedigree of these animals included 12 863 individuals. The study consisted in analysis of the pedigree structure of the horses and characterization of the homozygosity and genetic diversity in the population. It was found that pedigree completeness and depth were sufficient for reliable assessment of the genetic diversity in the analyzed population. Although the average inbreeding coefficient exhibited at an acceptable level (approx. 1.01%), the increasing percentage of inbred animals seems disturbing. The results have shown that modern sport horses are derived from a small number of high-quality sires whose offspring were intensively used for breeding—bottleneck effect. In consequence, a greater part of the genetic variation reduction was observed in the non-founder generations. Given the changes in the studied population, the level of inbreeding in modern sport horses should be monitored, and pedigree data should be effectively used in selection for mating.

Behaviour and stress in three breeds of laying hens kept in the same environment

The aim of the study was to determine whether birds of different breeds, with different preferences for environmental elements and kept in identical conditions, would exhibit different behaviour and stress levels. The research material consisted of 50 laying hens of the Green-legged partridge (Zk), Polbar (Pb), and Leghorn (Lg) breeds. The birds were provided with identical environmental conditions. They were kept on litter in separate boxes, with 25 individuals of one breed per box, in the same building. An open field test was used in determining the behaviour of the birds. Levels of cortisol in serum and corticosterone in feathers were evaluated, and haematological and biochemical analyses of blood were performed. Leghorns proved to be a highly excitable and active breed whose needs cannot be fully satisfied in the standard conditions of large farms. Based on a differential leukocyte count, their hyperactivity was associated with increased stress. The Green-legged partridge exhibited the lowest stress levels. Birds kept in the same environmental conditions were found to differ significantly in the level of stress, probably because of differences in their behavioural needs and the possibilities of satisfying them. To reduce stress levels and improve the welfare of hens, it is necessary to verify their preferences first. Stress indicators are elevated in highly excitable birds, and the conditions on large farms are not conducive to meeting their behavioural needs. Keywords: behavioural test, blood indices, corticosterone, laying hens

Effects of Yeast (Saccharomyces Cerevisiae) Probiotics Supplementation on Bone Quality Characteristics in Young Japanese Quail (Coturnix Japonica): The Role of Sex on the Action of the Gut-Bone Axis

Simple Summary

The gastrointestinal tract; as an important mediator of nutrients and elements; regulates bone health. In this study, we examined the effect of supplementation with yeast Saccharomyces cerevisiae on bone characteristics in young Japanese quails. We found that yeast probiotics, through their action on the gut-bone axis, have a positive effect on the structure of articular cartilage and microarchitecture of trabecular bone in young female quails. These data could provide useful information for further research into the supplementation with yeast probiotics aimed to reduce the risk bone fractures during the egg-laying period

Abstract

The aim of the study was to investigate the changes in bone geometry, histological structure, and selected mechanical characteristics in young male and female Japanese quails supplemented with Saccharomyces cerevisiae. Quails were fed a basal diet containing no yeast or a basal diet supplemented with 1.5% (15 g per 1 kg of diet) of inactive S. cerevisiae, for a period of 42 days. S. cerevisiae inclusion had no effect on bone weight, length, and density, diaphysis geometry (cross-sectional area, wall thickness, moment of inertia) or on the mechanical strength (yield load, ultimate load, stiffness, Young’s modulus, yield stress, ultimate stress). Yeast supplementation improved the morphology of the articular cartilage both in male and female quails, as the total thickness of the articular cartilage was significantly increased. In trabecular bone, an increase in real bone volume and trabecular thickness was observed in females supplemented with S. cerevisiae, while in males the increase in trabecular number was accompanied by a reduction in trabecular thickness. The results of the present study demonstrate that S. cerevisiae, through a sex-dependent action on the gut-bone axis, improved the structure of articular cartilage and microarchitecture of trabecular bone. The positive effects of S. cerevisiae supplementation were more evident in female quails.

Variability of laying hen behaviour depending on the breed

OBJECTIVE

For many generations, most species of farm animals have been subjected to intense and strictly targeted selection for improvement of their performance traits. This has led to substantial changes in animal anatomy and physiology, which resulted in considerable differences between the current animal breeds and their wild ancestors. The aim of the study was to determine whether there is breed-specific variability in behaviour as well as differences in emotional reactivity and preferences of laying hens.

METHODS

The investigations involved 50 Green-legged Partridge, 50 Polbar, and 50 Leghorn hens. All birds were kept in the same conditions, and the behavioural tests were carried out at 30 weeks of age. We used the tonic immobility test and a modified open-field test including such objects as water, commercial feed, feed enriched with cereal grains, finely cut straw, and insect larvae, a sandpit, a mirror, and a shelter imitating a hen nest.

RESULTS

The research results demonstrate that the birds of the analysed breeds differ not only in the excitability and emotional reactivity but, importantly, also in the preferences for environment-enriching elements. Ensuring hens' well-being should therefore be based on environmental modifications that will facilitate acquisition of essential elements of chickens' behaviour. The greatest emotional reactivity was found in the Leghorn breed, which may be a result of correlated selection aimed at an increase in chicken productivity.

CONCLUSION

The differences in the behaviour of the birds from the analysed breeds indicate that laying hens cannot be regarded as one group of animals with the same environmental requirements.

Characterisation of genome-wide structural aberrations in canine mammary tumours using single nucleotide polymorphism (SNP) genotyping assay

Characterisation of copy number variation (CNV) and loss of heterozygosity (LOH) has pro- vided evidence for the relationship of this type of genetic variation with the occurrence of a broad spectrum of diseases, including cancer lesions. The role of CNVs and germinal or somatic LOHs in canine mammary tumours is still unknown. Therefore, the aim of this study was to identify CNVs and LOHs in canine mammary tumours. Forty-eight samples obtained from normal (n=24) and tumour (n=24) tissues of dogs were analysed. In the study, we used CanineHD BeadChip assay (Illumina) and OncoSNP software to identify copy number alternations in genomes of dif- ferent dog breeds and in different mammary cancer types occurring in this species. The analyses revealed that, in the case of CNV, the amplification-type variants were longer and more frequent than deletions. Based on the analysis of the frequency of different types of aberrations in the in- dividual parts of the genome, regions that are particularly susceptible to structural aberrations were indicated. The fraction of genes identified within these regions was associated with major processes of neoplastic transformation. Association analysis of such traits as tumour grading as well as the size and age of dogs demonstrated that structural aberrations were more frequent in dogs diagnosed with tumour malignancy grade II and III, in dogs with a larger body size, and in large dogs aged 7-8. The promising results of these pioneering investigations prompt continuation thereof to analyse other types of cancer.

Intestinal mucosa develops in a sex-dependent manner in Japanese quail (Coturnix japonica) fed Saccharomyces cerevisiae

1. The aim of study was to investigate whether the impact of the yeast Saccharomyces cerevisiae on the histological structure of the intestine, innervation of the small intestine wall, and basal biochemical serum parameters in Japanese quail was sex dependent. 2. One-day-old healthy male and female Japanese quail were fed either a basal diet containing no yeast (control group) or the basal diet plus 1.5% (15 g/kg of diet) of yeast (S. cerevisiae inactivated by drying). Samples from the duodenum and jejunum were taken from each bird at the age of 42 days. Blood samples were collected at this age and the concentrations of glucose, total protein, creatinine, uric acid, lipid profile (total cholesterol, low density lipoproteins (LDL), high density lipoproteins (HDL) and triacylglycerols (TG)), alanine aminotransferase (ALAT), aspartate aminotransferase (AspAT), lactate dehydrogenase (LDH), amylase (AMY), calcium, phosphorus and iron were determined. 3. Female quail fed diets supplemented with yeast had significantly lower total cholesterol and amylase activity than the control females. The concentration of HDL was higher in the male quail than in the females, irrespective of the treatment. An opposite effect was observed in LDL. The diet treatments influenced the activity of AspAT, which was significantly less in the male quail fed diets with 1.5% yeast. 4. Supplementation with S. cerevisiae increased the myenteron, submucosa and mucosa thickness, villus length and thickness and size of absorptive surface, while the number of villi and enterocytes were decreased in the duodenum in males. Female quail showed an increased absorptive surface in the jejunum. The Meissner (submucosal) plexuses were influenced by the feeding and sex to a greater extent than the Auerbach plexus (in the muscularis propria). 5. The results demonstrated that S. cerevisiae (1.5%) in the diet caused significant positive effects in Japanese quail, exerting an effect on the morphology of the small intestine in a sex-dependent manner.

Effects of L-carnitine on morphology and cellular parameters of hen erythrocytes

The aim of our study was to determine the influence of L-carnitine (L-CAR) on the cellular parameters of hen erythrocytes during a 48 hour exposure to L-CAR at concentrations of 25, 50 and 100 µg/mL in nutrient-deficient medium. Cell morphology, haemolysis, caspase 3/7 activity and glucose uptake (GU) were determined. The results showed a lower percentage of apoptotic cells and decreased haemolysis of erythrocytes treated for 48 hours at all the concentrations of L-CAR. The amino acid at 50 µg/mL inhibited the activity of proapoptotic caspase 3/7; however, it increased GU. In contrast, caspase 3/7 level was increased but GU was decreased in erythrocytes treated with 100 µg/mL of L-CAR when compared to the control. It may be hypothesized that reduction of apoptotic changes in hen erythrocytes may result from increased GU.

Long-bone properties and development are affected by caponisation and breed in Polish fowls

1. The aim of the study was to investigate the effects of caponisation on bone development of males of two native breeds in Poland. 2. The weight, length and cross-sectional area of tibiae and femora were measured, densitometric measurements and tests of strength were determined and dimensions were calculated. 3. Breed and caponisation did not influence bone weight and length. Higher mechanical strength of the femur was found in entire males, mainly in the Polbar breed. Tibial strength was reduced in capons of the Green Partridge breed. Maximum elastic strength was greater in the Polbar, irrespective of caponisation. Bone cross-sectional area was influenced by breed, while caponisation reduced femoral bone mineral density in both breeds. 4. Caponisation thus increased growth rate but had adverse effects on bone development. 5. Caponisation had fewer negative effects in the Polbar than in the Greenleg Partridge.

Effect of caponization on performance and quality characteristics of long bones in Polbar chickens

The effect of caponization on the mechanical properties of Polbar chicken bones was the subject of investigation. The biomechanical strength of bones and the risk of their deformation or fracture were determined on the basis of their geometric, structural, material, and densitometric properties. Eight-week-old cockerels of Polbar breed were surgically castrated and then fattened until the 24th week of life. It was observed that caponization did not influence the weight and length of either of the long bones. It did however significantly reduce their ash content and the Ca and P contents in their femur, and P content in their tibia. Dual energy x-ray absorptiometry densitometry revealed that bone mineral content of the mid-diaphyseal part of both bones were reduced. Similarly, the bone tissue density of bones decreased. Caponization influenced the bone's geometric structure increasing the internal and external diameters of the bones. The bone cross-sectional area was greater in capons, and, consequently, the cross-sectional moment of inertia and the radius of gyration significantly increased. However, the relative wall thickness and cortical index were not altered. The three-point bending tests revealed the negative effect of caponization on the mechanical endurance of bones. Yield strength, Young modulus, and yield stress, characterizing the strength of the bone's material, decreased in capons. That suggests a higher risk of permanent deformation as capon bones become less elastic. Concluding, caponization negatively influenced the quality characteristics of Polbar chicken long bones.

Single-nucleotide polymorphism of MC1R, ASIP, and TYRP2 genes in wild and farmed foxes (Vulpes vulpes)

DNA mutations within genes associated with melanogenesis can affect melanin production, leading to dyschromias. Genes that are involved in synthesis of melatonin and may affect the color of skin are melanocortin 1 receptor (MC1R), agouti locus (ASIP), and tyrosinase-related protein-2 (TYRP2). In this study, SNP identification within ASIP, MC1R, and TYRP2 gene fragments in wild and farmed foxes (Vulpes vulpes) was performed. Nine mutations in the ASIP gene which allowed us to distinguish seven SNP profiles, fourteen mutations and five SNP profiles in the MC1R gene, and seven SNP profiles based on four polymorphic nucleotides in the TYRP2 gene were detected. Analyses of obtained profiles indicate that ASIP did not undergo mutations in the wild, and significant variability of SNP profiles was found for TYRP2, with specific haplotypes noted for farm foxes and American and European wild foxes.

Analysis of Genetic Variability in Farmed and Wild Populations of Raccoon Dog (Nyctereutes Procyonoides) Using Microsatellite Sequences

The aim of this study was to detect possible differences between farmed and wild-living raccoon dogs. Analysis of polymorphism in 15 microsatellite sequences led to the conclusion that raccoon dogs raised on Polish farms and wild raccoon dogs living in Poland are two genetically distinct groups of animals. Wild Polish raccoon dogs are genetically more similar to the population of wild animals from the Kaliningrad Region than to farmed animals. The analysis of microsatellite loci showed clear genetic differences between farmed and wild-living populations of raccoon dog, despite only 50 years of isolation of the two groups of animals. The farmed population was characterized by higher genetic variation than the wild-living population. On the basis of the analyses three microsatellite loci (INU014, Ren13J22 and Ren41D20) were proposed for determination of the origin of animals that have escaped from farms.

Selenium intake of infants and young children, healthy children and dietetically treated patients with phenylketonuria

In 20 healthy infants and children, 5-20 months old, the Se intake was estimated by analysing food samples by instrumental neutron activation analysis. The intake was calculated by weighing the portions offered and actually consumed. The median Se content of the food amounted to 27 ng/g wet weight (gww) and median daily Se intake to 33.5 micrograms. The Se intake was not equally distributed over the day. About 50% of the daily Se intake was derived from the supper. The main Se sources (41%) for young children were cereal paps. Commercially available meals (30 ng/g) contained less Se than home-made ones (50 ng/g). In nine dietetically treated patients with phenylketonuria the median Se intake amounted only to 6.9 micrograms/day corresponding to a mean Se content of the diet of 7.9 ng/g. The main Se source in the diet was vegetables (36.3%) and 20% derived from their protein supplements. The Se intake of young children, healthy or dietetically treated, cannot be calculated accurately from tables but must be estimated by measuring the Se content of the local food because cereals and vegetables--the main Se sources--exhibit great regional variations.

The selenium content of infant food

The selenium content of food exhibits great regional differences. Food samples of infants and young children from the North Rhine-Westphalia State in the Fed. Rep. of Germany were analysed by instrumental neutron activation analysis and showed that the average selenium content of local vegetable and fruit is below 5 ng/g wet weight. Only samples of potatoes and bananas exhibit higher selenium contents. The bananas, probably imported from different areas of the world, show an extremely high variance with values between 4 and 164 ng Se/g. Commercially available ready-for-use meals for infants or young children have a low Se content (median 24 ng/g) which is comparable to cow's milk. Besides eggs, cereals enriched with milk and some other cereal products contain more than 100 ng Se/g.

Estimation of zinc and other trace elements in the nails of Hungarian adult twin pairs by neutron activation analysis

Nail samples of 157 adult Hungarian twin pairs were examined for different trace elements by neutron activation analysis. Comparing the within-pair-concordance for zinc contents of the twins of different zygosity, a much higher concordance in monozygotes than in dizygotes was observed. The authors suggest the idea that the zinc content in the human organism, at least in some organs, may be genetically controlled.

Zinc status of Libyan children -- a pilot study

Hair zinc has been investigated in children of North and South Libya. The hair zinc content amounts to 213 +/- 36 micrograms/g in newborns. There is no difference between the values of newborns from North Libya and newborns from South Libya. The hair zinc values decrease during infancy. In toddlers and school-children the hair zinc content is 88 +/- 35 micrograms/g, 89 +/- 25 micrograms/g resp. These values are as low as those reported in American children with low height percentiles or nearly as low as those found in dwarfs with poor zinc status from Egypt and Iran.

Hair selenium content during infancy and childhood

Hair selenium content was estimated by instrumental neutron activation analysis in Libyan infants and children. There was no significant difference between the values of young infants from North and South Libya. The hair selenium content rapidly decreased from 1071 +/- 75 ng/g in newborns to 301 +/- 99 ng/g in 7-10 months old infants in North Libya and to 557 +/- 204 ng/g in South Libya. In North Libya the values of preschool children were 409 +/- 117 ng/g and those of school children 464 +/- 124 ng/g.

Selenium supplementation: plasma glutathione peroxidase an indicator of selenium intake

Plasma glutathione peroxidase activity is markedly reduced in dietetically treated patients with PKU or MSUD in comparison to health children of the same age. This is due to the low selenium content of their diet. During supplementation with yeast rich in selenium (200 micrograms selenium per day) for 3 months 2 healthy adults did not show any significant change of their plasma GSHPx activity. 5 dietetically treated patients with PKU or MSUD and a reduced selenium state showed a rapid increase of the plasma GSHPx activity after selenium supplementation were started with 120 micrograms Se/m2 x d. The values doubled within the first two days and reached a plateau after 1--3 weeks. The patients showed no clinical anomalities before or during the selenium supplementation besides the inherited defect of amino acid metabolism. Plasma GSHPx activity seems to be a good indicator of short-term changes of selenium intake in patients with reduced selenium state.

Determination of Co, Cu, Fe, Hg, Mn, Sb, Se and Zn in milk samples

Concentrations of Co, Cu, Fe, Hg, Mn, Sb, Se and Zn in IAEA milk (dry) standard A-11 were re-evaluated with the help of instrumental and radiochemical neutron activation analysis (NAA). The results show reasonably good agreement for Co (5.1 +/- 0.55 ng/g) and Zn (34 +/- 2.5 micrograms/g), in relation to the recommended values. For Cu (374 +/- 15 ng/g), Fe (2.4 +/- 0.34 microgram/g) and Mn (250 +/- 20 ng/g); the results obtained are lower than the reported values. Cu, Mn, and Zn were cross-checked by atomic absorption spectrophotometry (AAS). The results, Cu = 331 +/- 27 ng/g, Mn = 302 +/- 62 ng/g, and Zn = 35 +/- 1 microgram/g, fall within the range of mean values obtained by NAA. for Hg and Se, using instrumental NAA, only upper limits could be indicated; because of the low levels of concentrations of Hg and Se on one hand, and high content of P (9100 micrograms/g) in A-11 milk standard on the other, NAA coupled with radiochemistry is to be preferred for these two elements. In pooled human milk, in addition to Cu and Mn (radiochemical) and Co, Fe, Sb and Zn (instrumental), Hg and Se could also be determined non-destructively because of the favorable Hg/P and Se/P ratios in this matrix.

Trace element concentration in the human pineal body. Activation analysis of cobalt, iron, rubidium, selenium, zinc, antimony and cesium

100 human pineal bodies (56 male and 44 females) were analyzed by means of instrumental neutron activation analysis for trace concentrations of cobalt, iron, rubidium, selenium, zinc, antimony and cesium. The results indicated that the measured element concentrations are not related to body-surface, age and fresh weight. Moreover, the mean absolute cobalt value from 97 pineal bodies is increased by a factor of 1.43 over the mean absolute concentration value of 257 other areas of the brain. The mean zinc content is found to be 3.7 fold higher than the mean zinc value from 269 other samples of brain. The iron values from various brain areas do not differ from those of the pineal body. Compared to other brain regions pineal selenium is increased and rubidium is decreased. Correlating the different element concentrations to each other, a positive correlation is found for selenium and ribidium, a negative correlation for cobalt and zinc. The present data suggest that the measured trace elements are somehow related to specific roles in the physiology and biochemistry of the pineal body. This is supported by the constancy of element concentration over a wide range of increasing fresh weights of the organ. It is considered that zinc, cobalt and iron are involved as constituents of enzymes in the metabolism of amino acids, peptides and proteins of the pineal body. Moreover the conspicuous high zinc content of this organ may be related to a so far undetected neurotransmitter.

Platelet selenium in children with normal and low selenium intake

The concentration of selenium was determined by instrumental neutron activation analysis in erythrocytes, platelets, and plasma of eight dietetically treated children with phenylketonuria (n=6) or maple-syrup-urine disease (n=2) with low selenium intake and for ten children with normal selenium intake. The normal selenium concentration in platelets was about 600 ng/g and about five times higher than in erythrocytes of the same children. A decreased selenium concentration in platelets was seen only when the corresponding concentrations in erythrocytes and plasma were very low. This suggests a special role of selenium in platelets.

Multielement analysis of fingernail, scalp hair and water samples from Egypt (a preliminary study)

Scalp hair, fingernail and water samples collected from different parts of Egypt are analysed by atomic absorption spectrophotometry and neutron activation analysis. The results for hair show minimum variation of Zn among different regions; a relatively well-controlled dispersion of values (maximum to minimum less than 2) for Co, Fe, Mn and Se; an overall inter-regional variation of factors of 7, 10, 6, 4 and 6 for the elements Ag, Cd, Cs, Sc and W, respectively; a steady decline in the concentration of Sc from south (Aswan) to north (Alexandria). The findings for nail show a steady decline in the concentration of Fe and Sc from south (Aswan) to north (Alexandria); elevated levels of Cd in samples from Aswan area; and regional variations extending up to factors of 6.5, 3.6, 4.7, 5.9, 4.4, 4.5 and 1.9 for Co, Cr, Cs, Mn, Mo, W and Zn, respectively. No unified relationship is observed between the elemental compositions of hair and nail. For Cr, Cs, Fe, Sb and Sc mean values for hair are lower than in nails. Among the remaining elements the ratio nail/hair is less than 1 for Ag in Assiut, El Kharga and Alexandria, for Cd in all of the areas with the exception of Aswan, for Co, Mn and Mo in Cairo, for Zn in Cairo and Alexandria, and for W in Alexandria. The data for water samples reflect highest concentration of all the measured elements in the Mediterranean sea; a steady increase of the concentration of Cu in drinking water from south to north and for Nile water a similar trend for Ca and Mg; and elevated concentrations of Sb and Mn in river water. No distinct trend for the interrelationship between water and tissue elemental concentrations could be established for the regions around Cairo, Aswan and Alexandria.

Selenium and myocardial infarction: glutathione peroxidase in platelets

The activity of the selenoenzyme glutathione peroxidase (EC 1.11.1.9) was determined in platelets of 15 patients with acute myocardial infarction and 13 control subjects. The platelets of the patients had significantly lower activities of the enzyme (P(t) greater than 0.99). This may be related to the pathogenesis of the disease.

Concentration differences between serum and plasma of the elements cobalt, iron, mercury, rubidium, selenium and zinc determined by neutron activation analysis

The differences in concentrations of cesium, cobalt, iron, mercury, rubidium, selenium and zinc between serum and plasma were examined with the aid of instrumental neutron activation analysis. Eighty serum and plasma samples obtained from 13 donors were compared. Serum was prepared in plastic tubes immediately after clotting, and plasma was separated with heparin as anticoagulant. No significant differences in the concentrations of cesium, cobalt, mercury and selenium were observed. However, the concentrations of iron, rubidium and zinc were significantly higher in serum than in plasma. The average differences were 322, 12 and 20 ng/ml for iron rubidium and zinc, respectively. The average differences found for cesium, rubidium and zinc were far below that which can be expected from a complete, or considerable release of these elements from platelets which aggregate or disintegrate during the clotting process in preparing serum.

Rubidium-A possible essential trace element : 1. The rubidium content of whole blood of healthy and dietetically treated children

The rubidium content of whole blood was estimated by instrumental neutron activation analysis. In 46 healthy children it amounts to {ie193-1} g/g dry weight. There was no difference between the values found for infants, toddlers, and school children. In 29 dietetically treated patients with phenylketonuria and maple-syrup-urine disease the values were significantly lower than in healthy children. During the first three months of diet therapy the rubidium levels remained in the lower range of the normal values, decreasing to about 60% of the mean of normal values later on. With increasing length of diet therapy these values tended to decrease. It remains questionable whether these decreased levels reflect only an induced biochemical phenomenon without biological importance, or whether they are the first signs of a deficiency syndrome.

Selenium requirements in patients with inborn errors of amino acid metabolism and selenium deficiency

The diets of 5 patients with phenylketonuria of maple-syrup-urine disease were supplemented with yeast which was rich in selenium. For 120 days the patients received 45 micrograms Se/day to increase the Se content of their diets to 10--12 ng Se/Kjoule. Before supplementation the selenium content of serum (5--15 ng/ml) and whole blood (10--27 ng/ml), and the activity of the erythrocyte glutathione peroxidase (0.19--2.69 U37/g Hb), amounted to only 10--20% of normal. The serum selenium content reached normal values within 4 weeks of supplementation, followed by normalisation of the selenium content of whole blood within 4--8 weeks. Restoration of the activity of erythrocyte glutathione peroxidase took 9 to 15 weeks--the red cell life span. There was a significant positive correlation between the selenium content of the erythrocytes and the activity of erythrocyte glutathione peroxidase.

Elemental composition of platelets. Part I. Sampling and sample preparation of platelets for trace-element analysis

Sampling of platelets for trace-element analysis poses special problems: obtaining adequate sample material, achieving a sufficient cell purity, preserving viability (integrity), correcting for trapped plasma, and controlling contamination. We used a blood-cell separator for the primary isolation of platelets from blood, and differential centrifugation in natural plasma to further isolate them. The pyrimidopyrimidine RA233 was used as a stabilizer to maintain viability. 131I-labeled human serum albumin was used to estimate trapped plasma. Contamination was controlled by using five-times-distilled water to simulate donor's blood in the system and by comparing three fractions: the serum, the first portion of the platelet-rich plasma, and the supernatant plasma after the final centrifugation. Neutron activation analysis was used for the elemental analysis. A single differential centrifugation of the platelet-rich plasma from the blood-cell separator at 400 x g for 8 min was optimum (mean mass fractions:erythrocytes/platelets less than 5 mg/g and leukocytes/platelets less than 20 mg/g). The trapped plasma in the wet platelet samples amounted to about 0.40 g/g. No appreciable contamination from the sampling system was found for the elements Ag, Cd, Co, Cr, Cs, Cu, Fe, Mo, Rb, Sb, Se, and Zn.

Elemental composition of platelets. Part III. Determination of Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se in normal human platelets by neutron activation analysis

The elements Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se were determined in platelets from seven normal donors. The results, in ng/g wet weight, for plasma-free platelets follow: "Pure" platelets: Ag = 29 +/- (18), au = 0.22 +/- (0.22), Cd = 6.2 +/- 3.4, Cs = 54.8 +/- 19.2, Cr = 6.1 +/- 2.5, Co = 7.5 +/- (5.0), Mo = 3.4 +/- 1.3, Rb = 10400 +/- 3000, Sb = 18 +/- (26), and Se = 782 +/- 127. "Impure" platelets: Au = 0.23 +/- (0.28), Cd = 6.4 +/- 2.6, Cs = 35.2 +/- 13.8, Cr = 8.2 +/- 2.9, Co = 2.9 +/- (3.0), Mo = 3.2 +/- 0.8, Rb = 8700 +/- 1700, Sb = 13.2 +/- (8.7), and Se = 679 +/- 57. To our knowledge, none of these 10 trace elements has been determined in platelets before. The selenium concentration in platelets exceeds that in other tissues (e.g., liver). We suggest that glutathione peroxidase or other unknown selenoenzymes are particularly important in platelet metabolism. Platelets are crucial for triggering thrombosis, and so may be involved as links between selenium deficiency and the concomitant increased death rate from cardiovascular disease.

Elemental composition of platelets. Part III. Determination of Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se in normal human platelets by neutron activation analysis

The elements Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se were determined in platelets from seven normal donors. The results, in ng/g wet weight, for plasma-free platelets follow: "Pure" platelets: Ag = 29 +/- (18), au = 0.22 +/- (0.22), Cd = 6.2 +/- 3.4, Cs = 54.8 +/- 19.2, Cr = 6.1 +/- 2.5, Co = 7.5 +/- (5.0), Mo = 3.4 +/- 1.3, Rb = 10400 +/- 3000, Sb = 18 +/- (26), and Se = 782 +/- 127. "Impure" platelets: Au = 0.23 +/- (0.28), Cd = 6.4 +/- 2.6, Cs = 35.2 +/- 13.8, Cr = 8.2 +/- 2.9, Co = 2.9 +/- (3.0), Mo = 3.2 +/- 0.8, Rb = 8700 +/- 1700, Sb = 13.2 +/- (8.7), and Se = 679 +/- 57. To our knowledge, none of these 10 trace elements has been determined in platelets before. The selenium concentration in platelets exceeds that in other tissues (e.g., liver). We suggest that glutathione peroxidase or other unknown selenoenzymes are particularly important in platelet metabolism. Platelets are crucial for triggering thrombosis, and so may be involved as links between selenium deficiency and the concomitant increased death rate from cardiovascular disease.

Elemental composition of platelets. Part I. Sampling and sample preparation of platelets for trace-element analysis

Sampling of platelets for trace-element analysis poses special problems: obtaining adequate sample material, achieving a sufficient cell purity, preserving viability (integrity), correcting for trapped plasma, and controlling contamination. We used a blood-cell separator for the primary isolation of platelets from blood, and differential centrifugation in natural plasma to further isolate them. The pyrimidopyrimidine RA233 was used as a stabilizer to maintain viability. 131I-labeled human serum albumin was used to estimate trapped plasma. Contamination was controlled by using five-times-distilled water to simulate donor's blood in the system and by comparing three fractions: the serum, the first portion of the platelet-rich plasma, and the supernatant plasma after the final centrifugation. Neutron activation analysis was used for the elemental analysis. A single differential centrifugation of the platelet-rich plasma from the blood-cell separator at 400 x g for 8 min was optimum (mean mass fractions:erythrocytes/platelets less than 5 mg/g and leukocytes/platelets less than 20 mg/g). The trapped plasma in the wet platelet samples amounted to about 0.40 g/g. No appreciable contamination from the sampling system was found for the elements Ag, Cd, Co, Cr, Cs, Cu, Fe, Mo, Rb, Sb, Se, and Zn.

Elemental composition of platelets. Part II. Water content of normal human platelets and measurements of their concentrations of Cu, Fe, K, and Zn by neutron activation analysis

We determined the elements Cu, Fe, K, and Zn in normal human platelets by neutron activation analysis. The platelets were obtained from seven donors and treated as described in Part I. The elemental composition is expressed on a wet-weight basis for plasma-free platelets. The following results were obtained (+/- values are 1 SD); "Pure" platelets: trapped plasma = 378 +/- 35 mg/g, water content = 715 +/- 15 mg/g, mean weight of the single platelet (by two different methods) = 9.9 +/- 1.1 pg and 11.2 +/- 1.7 pg, K = 4.39 +/- 1.06 mg/g, Zn = 49.23 +/- 10.97 microgram/g, Fe = 12.28 +/- 2.94 microgram/g, and Cu = 1.39 +/- 0.25 microgram/g. "Impure" platelets: trapped plasma = 349 +/- 31 mg/g, water content = 736 +/- 12 mg/g, K = 3.26 +/- 0.78 mg/g, Zn = 35.71 +/- 7.99 microgram/g, Fe = 17.11 +/- 5.10 microgram/g, and Cu = 1.39 +/- 0.21 microgram/g. To our knowledge, no data on Fe and Cu in platelets have hitherto been reported.

Elemental composition of platelets. Part II. Water content of normal human platelets and measurements of their concentrations of Cu, Fe, K, and Zn by neutron activation analysis

We determined the elements Cu, Fe, K, and Zn in normal human platelets by neutron activation analysis. The platelets were obtained from seven donors and treated as described in Part I. The elemental composition is expressed on a wet-weight basis for plasma-free platelets. The following results were obtained (+/- values are 1 SD); "Pure" platelets: trapped plasma = 378 +/- 35 mg/g, water content = 715 +/- 15 mg/g, mean weight of the single platelet (by two different methods) = 9.9 +/- 1.1 pg and 11.2 +/- 1.7 pg, K = 4.39 +/- 1.06 mg/g, Zn = 49.23 +/- 10.97 microgram/g, Fe = 12.28 +/- 2.94 microgram/g, and Cu = 1.39 +/- 0.25 microgram/g. "Impure" platelets: trapped plasma = 349 +/- 31 mg/g, water content = 736 +/- 12 mg/g, K = 3.26 +/- 0.78 mg/g, Zn = 35.71 +/- 7.99 microgram/g, Fe = 17.11 +/- 5.10 microgram/g, and Cu = 1.39 +/- 0.21 microgram/g. To our knowledge, no data on Fe and Cu in platelets have hitherto been reported.

Selenium content of human milk, cow's mild and cow's milk infant formulas

The selenium content of human milk, cow's milk and cow's milk infant formula were estimated by instrumental neutron activation analysis. The highest values were found in 3 samples of human colostrum (524--865 x 10(-9) g/g dry weight). There was a significant decrease with increasing time post partum. Mature human milk exhibited a selenium content of 230 +/- 79 x 10(-9) g/g dry weight. The selenium content of 45 samples of cow's milk from the north-western area of Germany was 200 +/- 39 x 10(-9) g/g dry weight. While there was no significant difference between the values of mature human milk and of cow's milk, cow's milk infant formula exhibited significantly (P less than 0.01) lower values than human milk. The average selenium content of 107 samples of 10 different commercially available fluid and powdered cow's milk infant formulas (range: 18--171 x 10(-9) g/g dry weight) amounted to about only one third of that in mature human milk.

The selenium state of children. II. Selenium content of serum, whole blood, hair and the activity of erythrocyte glutathione peroxidase in dietetically treated patients with phenylketonuria and maple-syrup-urine disease

The selenium content of serum, whole blood and hair was measured by neutron activation analysis in dietetically treated patients with phenylketonuria (PKU) and maple-syrup-urine disease (MSUD). Follow-up studies showed a decrease of the serum selenium content and the glutathione peroxidase activity of erythrocytes--a selenoenzyme--from normal values at the beginning of the diet to 20% (selenium) and 50% (gluthione peroxidase) of normal within 10--12 weeks of dietary treatment. In 36 patients the serum selenium content was lower at 6.7--28 X 10(-9) g/ml, independent of the age of the patients (0.5 to 10 years). The selenium content of whole blood was reduced: median = 98 X 10(-9) g/g dry weight; range 75 to 165 X 10(-9) g/g dry weitht (healthy children: median = 381 X 10(-9) g/g dry weight; range 245 to 588 X 10(-9) g/g dry weight). The selenium content of hair was markedly lower in the patients (median = 62 X 10(-9) g/g; range 13--140 X 10(-9) g/g) than in healthy children (median = 429; range 213 to 720 X 10(-9) g/g). The mean glutathione peroxidase activity of erythrocytes was reduced to 4.6 +/- 0.64 U37/g Hb, comparison to normal values (mean = 8.8 +/- 0.88 U37/g Hb).

Determination of certain selected bulk and trace elements in the bovine liver matrix using neutron activation analysis

Effective utilisation of neutron activation analysis (NAA) for the elemental analysis of biomedical samples with or without a radiochemical separation, especially when optimal Ge(Li) well type detectors are employed for the acquisition of complex spectra, is demonstrated by determining normal values for 25 elements in bovine liver. Optimal conditions for the determination of Ag, Br, Cl, Co, Cs, Fe, I, K, Mn, Na, P, Rb, Sb, Sc, Se and Zn with the aid of instrumental thermal neutron activation analysis (INAA) by varying the irradiation and decay time are presented. Where INAA was inadequate, simple post irradiation separation based on ion-exchange has been used to determine such elements as Au, Ca, Cd, Ce, Cr, Cu, La, Mo and W. Results from the IAEA intercomparison run for animal muscle (H-4) are also given. The influence of sample size with respect to within-tissue variation of the bulk and trace elements in liver and the contamination of liver samples from the interfering components such as residual blood are also discussed.

Serum zinc concentration during childhood

Serum zinc concentrations in subjects of different ages were estimated by neutron activation analysis to obtain reliable reference values for the diagnosis of primary or secondary zinc deficiency during childhood. In these healthy individuals a small age-dependent variation of the mean values was found. Serum zinc concentrations were lower in cord blood (mean value: 880 X 10(-9) g/ml) and in infant;s (mean value: 820 X 10(-9) g/ml) than in adults (mean value 1178 X 10(-9) g/ml). In comparison to these values, the serum zinc concentration in a patient with secondary zinc deficiency and 4 patients with acrodermatitis enteropathica was reduced to about 25% of normal.

The selenium state of healthy children. I. Serum selenium concentration at different ages; activity of glutathione peroxidase of erythrocytes at different ages; selenium content of food of infants

The selenium concentration of serum is age-dependent. The median value at birth (chi=50 X 10(-9)g/ml) amounts to half of the median value of adults (chi=102 X 10(-9)g/ml). After a decrease in early infancy to chi=34 X 10(-9)g/ml it steadily increases to chi=58 X 10(-9)g/ml in the second half of the first year, to chi=82 X 10(-9)g/ml in 1--5 year old children, and to chi=92 X 10(-9)g/ml in school children. The activities of the selenium containing enzyme glutathione peroxidase of erythrocytes are also reduced in early infancy (chi=7.2 +/- 0.36 U37/g Hb), whereas the enzyme activities of cord blood erythrocytes (chi=8.72 +/- 0.76 U37/g Hb) are in the same range as those of older children or adults. The selenium content of some commercially available milk formulas for infants are lower than those of human and cow's milk.