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In this study, differences in growth characteristics (body weight, femoral weight and femoral length) of adult male rats after single cadmium (Cd), as well as, simultaneous exposure to Cd and diazinon (DZN), and after DZN, Cd and selenium (Se) co-administration were investigated. One-month-old male Wistar rats were randomly divided into four groups of 10 animals each. In the first group (A), rats received a drinking water containing 30 mg of CdCl2/l for 90 days. In the second group (B), males were orally dosed with combination of40 mg of DZN/l and 30 mg of CdCl2/l in drinking water for 90 days. In the third group C, rats were administered by 40 mg of DZN/l in combination with 5 mg of Na2SeO3/l and 30 mg of CdCl2/l in drinking water for the same treatment period. The fourth group of males without additive toxicants, served as a control group (D). The statistical analysis of obtained data showed a beneficial effect of Cd sole dose on femoral weight in adult male rats. Significant changes in femoral weight were observed between rats from the groups A and B, and A and C. On the other hand, there were no significant differences in body weight and femoral length between all experimental (A, B, C) and control (D) groups. Considerable differences were identified only for femoral length among the groups A and C, and the groups B and C. Our results suggest a protective influence of Cd against Se-induced reduction in body weight and femoral length in rats simultaneously exposed to DZN, Se and Cd in their drinking water. However, positive influence of Cd on rat´s femoral weight is likely suppressed by the toxicity of DZN and/or DZN in combination with Se.

Background Humans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown. This study aimed to assess single and joint effects of cadmium and diazinon exposure on sperm quality parameters. Methods Male adult Wistar rats were randomized into 4 groups of ten animals each. Group A was used as a control, animals from group B were exposed to cadmium (30 mg/L), rats from group C were administered with diazinon (40 mg/L), and rats from group D were exposed simultaneously to cadmium (30 mg/L) and diazinon (40 mg/L) via drinking water for 90 days. Sperm morphology and motility were evaluated using a bright field microscope and a computer-assisted semen analysis. Results The percentage of motile spermatozoa and morphologically normal sperm was markedly reduced in rats from the group B. Rats from the C group showed an increase in velocity parameters, amplitude of lateral head displacement, decrease in beat-cross frequency, and an increase in abnormal sperm morphology. Simultaneous coexposure to cadmium and diazinon increased distance and velocity parameters, and amplitude of lateral head displacement. Reductions were observed in straightness, linearity, wobble, and beat-cross frequency. The decreased normal sperm morphology rates were related to defects of the sperm tail. Conclusions Exposure to cadmium and diazinon at relatively low doses impairs sperm quality and can reduce male fertility. Cadmium and diazinon caused significant changes on sperm morphology with varying effects on motility patterns. These parameters were significantly higher in the group D as compared to the group C. The findings have important implications for reproductive risk assessment of combined exposures to multiple chemicals.

The aim of this study was to examine effects of subchronic peroral administrations of cadmium and selenium on femoral bone microscopic structure in adult male rats. 1-month-old male Wistar rats were randomly divided into three groups, each containing 10 males. In the first group (EG1), rats were administered by cadmium at the dose of 30 mg of CdCl2/L in drinking water for 90 days. In the second group (EG2), animals received a drinking water containing 5 mg of Na2SeO3/L for the same treatment period. The third group of rats without cadmium and selenium applications, served as a control group (CG). At the end of the experiment (90 days), all animals were killed and their right femora were collected for microscopic evaluation. We found that the qualitative histological characteristics of the compact bone tissue were different in the middle part of compact bone in medial and lateral views between experimental (EG1, EG2) and control groups (CG). In Cd- and Se-treated rats, a smaller number of primary and secondary osteons was identified. Moreover, a few resorption lacunae were observed in rats perorally exposed to Cd (EG1). Histomorphometric evaluation showed a significant decrease (P

Objective : The purpose of the presera study was to devélop a molecular genotyping method test by using a real time PCR hybridization probé and applying it to the analysis of C1843T mutations of the Sus scrofa RYR1 gene. Animáis population Three PSS-susceptible and PSS non-susceptible crossbred swine races were used for the experiments: Pietrain X Landrace Belga, Pietrain X Large White and Pietrain X Duroc. Methods: We have devéloped a genotyping method by using a hybridization probé and applied it to the analysis of C1843T mutations of the RYR1 gene, associated with PSS susceptibility. Genotyping results obtained by hybridization probé strategies were confirmed by restriction analysis and sequencing. In addi-tion, phenotype/genotype correlation analyses were devéloped by using the in vitro contracture test and confirmed the in vivo hálothane-succinylcholine challenge. Results: The real-time PCR with fluorescent hybridization probé methodology was designed to identify ho-mozygous PSS-resistant, PSS-susceptible animáis as well as heterozygous carriers. All cases genotyped by fluorescent hybridization probes were in agreement with PCR restriction enzyme digestión and sequencing and showed a 100% concordance between the in vivo and in vitro porcine stress syndrome (PSS) susceptibility results. Conclusions and clinical relevance: The real-time PCR with fluorescent hybridization probé method described here provides a rapid, easily interpretable and réliáble tool for genotyping the C1843T (Arg615-Cys) polymorphism of the RYR1 gene. This new methodology may be useful in the wide-scale genotyping of PSS-susceptibility and genetic selection.

The purpose of this investigation was to study compact bone tissue microstructure of some mammals in terms of qualitative and quantitative characteristics, with an emphasis on finding an adequate identification key. Altogether, 36 femora of adult pigs, cows, sheep and rabbits were analysed. The qualitative characteristics were examined according to the classification systems of Enlow & Brown (1956) and Ricqles et al. (1991) in anterior, posterior, medial and lateral views of thin sections. The quantitative characteristics were assessed using the specific software Scion Image (Scion Corporation, US). We measured area, perimeter, and minimum and maximum diameter of the Haversian canals, the secondary osteons and the vascular canals of primary osteons. The observed data were first used to evaluate inter- and intra-species diversity. After that a discriminant function analysis was used for species determination. According to our results the basic structural pattern of the bone tissue was primary vascular plexiform in pigs, cows and sheep. We found dense Haversian bone tissue in all species. In addition, non-vascular bone tissue was identified in cows and/or primary vascular longitudinal tissue in rabbits. Many resorption lacunae were found between secondary osteons in pigs. The irregular Haversian bone tissue was localised at the periosteal and endosteal borders in sheep. Classification functions for all investigated species gave a correct classification in 73.83% of cases. The most discriminating variables for the compact bone tissue appeared to be perimeter and minimum diameter of primary osteon's vascular canals. The percentage value can be increased by integrating conclusions from the qualitative analysis. Copyright © 2006 John Wiley & Sons, Ltd.

We investigated the effect of the estrogen receptor (ESR) and ryanodine receptor (RYR1) genes on total number of born (TNB), number of born alive (NBA) and number of weaned (NW) piglets in Large White (LW), White Meaty (WM) and Landrace (L) sows from six Slovak breeding farms. We found a significant effect of ESR locus on NW (P≤0.01) in LW, however, we observed a negative effect of BB genotype on the trait. In WM, positive associations of B allele with TNB, NBA, NW were found but the differences were not confirmed statistically. A highly significant effect (P≤0.01) of ESR locus on TNB (+0.62±0.18 pigs per copy of B allele), NBA (+0.65±0.18) and NW (+0.51±0.16) was identified in L breed. With RYR1 gene we found significantly higher TNB and NBA in heterozygous WM sows (+1.01±0.36 in TNB; +0.87±0.32 in NBA; P≤0.01). NBA was also significant in LW (+0.41±0.19; P≤0.05).

Summary The aim of this study was to investigate differences in compact bone tissue microstructure between New Zealand White transgenic rabbits with human blood clotting factor VIII gene and the non-transgenic ones. The transgene was under the transcriptional control of the whey acidic protein (WAP) promoter. Altogether, 42 femora were analysed. Specimens were prepared using standard histological equipment, producing thin sections approximately 80–100 μm. Areas, perimeters, minimum and maximum diameters of vascular canals of primary osteons, Haversian canals and secondary osteons were measured. Our results indicate the basic structural pattern of the bone tissue was primary vascular longitudinal in both groups of rabbits. However, a fibrolamellar bone tissue was identified only in the transgenic rabbits. The measured variables of the vascular canals of the primary osteons, the Haversian canals and the secondary osteons were higher in transgenic rabbits in comparison with non-transgenic ones in most cases and the differences were often statistically significant (P

Summary The purpose of this investigation was to study in detail compact bone tissue microscopic structure of adult cows and pigs with an emphasis to find an adequate key for the species identification. Altogether 18 femurs were analysed. Each of the bones was sectioned at the smallest breadth of their diaphysis. Specimens were prepared using standard histological equipment, producing thin sections approximately 80–100 μm thick. The qualitative differences between investigated species were examined in anterior, posterior, medial and lateral views of thin sections. The quantitative ones were counted using the specific computer software Scion Image. We measured the area, perimeter, minimal and maximal diameter of the Haversian canals, the Haversian systems and the vascular canals of primary osteons. After that a discriminant function analysis was used for the species identification. According to our results the basic structural pattern of femur diaphysis was primary vascular plexiform in both species. However, non-vascular bone tissue was identified in cows and resorption lacunae were found between the secondary osteons in pigs. The measured variables of the Haversian canals, the Haversian systems and the primary osteon's vascular canals were higher in most cases in cows. Classification functions for investigated species give a correct classification of 64.69% of cases. This percentage value can be increased by integrating conclusions from the qualitative analysis.

Background Patulin, a toxic mold metabolite, has been found as natural contaminant of processed fruits, most notably apples, apple juices and other apple-based products. A number of adverse health effects in humans and animals are associated with patulin intoxication. The current study was performed to analyse possible toxic effects of patulin on femoral bone microstructure in adult rabbits in detail. Fourteen clinically healthy four-month-old rabbits of both sexes (6 males and 8 females) were included in the study. Animals from the experimental groups (group E♂, n = 3; group E♀, n = 4) were injected intramuscularly with patulin at dose 10 μg/kg body weight two times a week for 28 days. The dose of patulin was estimated based on the maximum permitted level of patulin for apple products intended for infants and young children. Three males and four females without patulin administration served as controls (groups C♂ and C♀). Cortical bone thickness and qualitative and quantitative histological characteristics of compact bone tissue were investigated. Results Intramuscular applications of patulin significantly increased the thickness of cortical bone in both sexes of rabbits. In patulin-exposed males, an absence of primary vascular longitudinal bone tissue near the endosteal border was observed, which could be associated with intensive bone remodeling. Femoral diaphyses of females displayed a lower number of secondary osteons in the middle part of the substantia compacta, and occurrence of the osteons near the periosteum. This could indicate alterations in bone turnover. Histomorphometrical evaluations showed significantly increased sizes of the primary osteons’ vascular canals (P

Background Chronic exposure to cadmium (Cd), even at low concentrations, has an adverse impact on the skeletal system. Histologically, primary and secondary osteons as basic structural elements of compact bone can also be affected by several toxicants leading to changes in bone vascularization and mechanical properties of the bone. The current study was designed to investigate the effect of subchronic peroral exposure to Cd on femoral bone structure including histomorphometry of the osteons in adult male rats. In our study, 20 one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males received a drinking water containing 30 mg of CdCl2/L, for 90 days. Ten one-month-old males without Cd intoxication served as a control group. After 90 days of daily peroral exposure, body weight, femoral weight, femoral length, cortical bone thickness and histological structure of the femora were analysed. Results We found that subchronic peroral application of Cd had no significant effect on body weight, femoral length and cortical bone thickness in adult rats. On the other hand, femoral weight was significantly increased (P

Osteoporosis is a serious disease characterized by high morbidity and mortality due to atraumatic fractures. In pathogenesis of osteoporosis, except environment, internal factors, such as hormonal dysbalance and genetic background, are also in play. In this review, candidate genes for osteoporosis are classified according to metabolic or hormonal pathways, which regulate bone mineral density/and or quality (estrogen, RANKL/RANK/OPG, mevalonate, Wnt circuit, genes for collagen and vitamin D). Authors discuss the perspectives of practical utilization of pharmacogenetics (identification of single candidate genes using PCR) or pharmacogenomics (using genome wide association studies) in choice of optimal treatment of osteoporosis. Potentional predictors of effectivity of antiresorption therapy are genes ER, FDPS, Cyp19A1, VDR, Col1A1 and gene of Wnt pathway. Moreover, polymorphisms of CYP2C gene, but also FDPS may identify patients with high risk of undesirable effects of bisphosphonates (osteonecrosis of jaw). Unfortunately, results of the most association studies has not been confirmed by other investigators. The controversial results could be explained by different methodic approaches in individual studies (different sample size, homogenity of investigated groups, ethnic differences or linkage disquilibrium between genes). Key cliff of association studies is low variability (7-10 %) of bone phenotypes associated with investigated genes. Nevertheless, identification of new genes and verification their association with bone density and/or quality using both PCR and genome wide association studies remain to be a great challenge targeting optimal prevention and treatment of osteoporosis.

Osteoprotegerin (OPG) plays an important role in the osteoclast differentiation as an effective inhibitor of osteoclast maturation and activation. We examined a potential effect of A163G single nucleotide polymorphism in the promoter region of the OPG gene on femoral neck (FN-BMD) and lumbar spine BMD (LS-BMD), as well as circulating alkaline phosphatase, osteocalcin (ALP, OC; formation markers), beta-CrossLaps (CTx; resorption marker) in Slovak postmenopausal women. In addition, fractures of spine, radius and femur were examined.Altogether 284 women (62.28 ± 8.40 years) were selected according to strict inclusion criteria. The polymorphism was detected by PCR-RFLP method. Genotype frequencies were tested using the chi-square test. The differences of quantitative variables between the genotypes were analyzed by covariance analysis (GLM procedure) after correction of the measurements for age and BMI. Fracture incidence in association with OPG genotype was evaluated by Binary Logistic Regression with the genotype, age, and BMI as covariates. The frequencies of genotypes were 76.8 %, 21.1 %, and 2.1 % for AA, AG, and GG, respectively. Statistically significant associations of OPG genotypes with FN-BMD (p < 0.01) and LS-BMD (p < 0.05) were observed. The GG genotype was associated with higher BMD values likewise decreased CTx concentration (p < 0.05) in compared with the other genotypes, which indicates that the allele G has a protective effect on bone. These associations were not followed by the effect of OPG on fracture incidence. Our results suggest that OPG/A163G polymorphism could contribute to the genetic regulation of BMD or bone turnover markers in Slovak population and thus could increase or decreased osteoporosis risk.

Histological sections of femoral diaphysis from adult sheep were investigated in this study. The qualitative characteristics in microstructure of the compact bone were examined in anterior, posterior, medial and lateral views; the quantitative ones were assessed using the software Scion Image. Areas, perimeters, minimum and maximum diameters of the Haversian canals, the Haversian systems and the primary osteons' vascular canals were measured. Our results indicate that ovine diaphysis of the femur is occupied mainly with primary vascular plexiform (laminar, fibrolamellar) tissue. In addition, irregular and dense Haversian bone tissues were observed. All measured variables disposed lower values in comparison with other artiodactyls (cattle and pig).

Background The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se. Methods Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na2SeO3/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy. Results The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons. Conclusions Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.

Free-living wild rodents are usually used as indicators of pollution, with elements being determined in either whole body or in specific organs. In the present study, the accumulation of cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in kidney, liver, testis, uterus and bone of yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) trapped in a polluted area of Nováky, Slovakia was investigated. Yellow-necked mice and bank voles were collected using standard theriological methods for wood ecosystems. All animals were adults in good physical condition. Concentrations of Cd, Cu, Fe, and Zn in all analyzed organs were determined by atomic absorption spectrophotometry. The highest concentrations of Cd and Zn were found in the bone of both species while Cu and Fe accumulated most in the uterus. Significantly higher concentrations of Cd and Cu were detected in the liver of the bank vole in comparison with the yellow-necked mouse (P0.05). Similar significantly higher levels of Cd and Zn were found in the bone of the bank vole (P0.05) than in the yellow-necked mouse, while these rodents had significantly higher Cu and Fe concentrations (P0.05) in the kidney. Significantly higher levels of Fe and Zn were detected in the testis and uterus of bank voles, respectively. On the other hand, significantly higher concentration of Cu was found in the testis of yellow-necked mice. Results of this study suggest that bank voles are more sensitive heavy metal loaded bioindicators than yellow-necked mice.

Background Exposure to cadmium (Cd) is considered a risk factor for various bone diseases in humans and experimental animals. This study investigated the acute effects of Cd on femoral bone structure of adult male rats after a single intraperitoneal administration. Methods Ten 4-month-old male Wistar rats were injected intraperitoneally with a single dose of 2 mg CdCl2/kg body weight and killed 36 h after the Cd had been injected. Ten 4-month-old males served as a control group. Differences in body weight, femoral weight, femoral length and histological structure of the femur were evaluated between the two groups of rats. The unpaired Student's t-test was used for establishment of statistical significance. Results A single intraperitoneal administration of Cd had no significant effect on the body weight, femoral weight or femoral length. On the other hand, histological changes were significant. Rats exposed to Cd had significantly higher values of area, perimeter, maximum and minimum diameters of the primary osteons' vascular canals and Haversian canals. In contrast, a significant decrease in all variables of the secondary osteons was observed in these rats. Conclusions The results indicate that, as expected, a single intraperitoneal administration of 2 mg CdCl2/kg body weight had no impact on macroscopic structure of rat's femora; however, it affected the size of vascular canals of primary osteons, Haversian canals, and secondary osteons.

Background Free-living wild rodents are often used as zoomonitors of environmental contamination. In the present study, accumulation of cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in critical organs of yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) trapped in a polluted area in Nováky, Slovakia was investigated. Methods Yellow-necked mice (n = 8) and bank voles (n = 10) were collected using standard theriological methods for wood ecosystems. All animals were adult males in good physical condition. The concentrations of Cd, Cu, Fe, and Zn in the liver, kidney, and bone were determined by atomic absorption spectrophotometry. Results The highest concentrations of Cd and Zn were found in the bone of both species while Cu and Fe accumulated mainly in kidney or liver. Significant higher concentrations of Cd and Cu were detected in the liver of bank voles than in yellow-necked mice. Similar significant higher levels of Cd and Zn were found in the bone of bank voles. In contrast, significant higher concentrations of Cu and Fe were present in the kidney of yellow-necked mice. Conclusions In the yellow-necked mouse and bank vole, bone seems to accumulate Cd and Zn following prolonged exposure. On the contrary, kidney and liver store Cu and Fe after a long-term environmental exposure. In the present study, bank voles seemed to be more heavy metal loaded zoomonitors than yellow-necked mice.

Heavy metal content in the femora of yellow-necked mouse (Apodemus flavicollis) and wood mouse (Apodemus sylvaticus) caught in different polluted biotopes of a low hill level in Slovakia (Novaky and Kolinany) was investigated in the present study. Length, weight and histological structure of mouse bones have also been analysed. According to our results, higher concentrations of Cd, Ni, Fe, Cu and Zn were detected in the femora of A. flavicollis from Kolinany area. Similarly, we observed higher concentrations of Ni, Fe, Cu and Zn in the bones of A. sylvaticus trapped at the same biotope. Significant differences were observed for concentrations of Ni and Zn in both species (P < 0.05). The measured values for bone length and bone weight were higher in yellow-necked mice and wood mice from Novaky locality (P < 0.01). Histological observation of thin sections from femora of A. flavicollis and A. sylvaticus revealed an outer and inner non-vascular lamellar layer around a poorly developed reticular layer. We did not identify demonstrable changes in qualitative histological characteristics of the femora between the mice (A. flavicollis and A. sylvaticus separately) from different types of polluted environment. Also, no statistically significant differences for all the measured variables of primary osteons’ vascular canals were observed. Correlation analysis in yellow-necked mouse showed high positive relation between bone weight and bone length (r = 0.66), area and perimeter (r = 0.87) and perimeter and maximum diameter (r = 0.87). In wood mouse, high positive correlation between bone weight and bone length (r = 0.80), area and perimeter (r = 0.72), area and maximum diameter (r = 0.66) and perimeter and maximum diameter (r = 0.74) was found. Our results demonstrate slightly elevated accumulation of some heavy metals in the femora of yellow-necked mouse and wood mouse from Kolinany biotope and thus give an evidence of a contamination of the environment.

One of the first questions asked about excavated human skeletal remains is the sex. As the morphological sex determination is complicated in cases involving fragmentary bones and in skeletons from infants and children, the development of DNA-based techniques has led to improvements in sex determination. This study is focused on sex determination from ancient DNA obtained from 25 skeletons found in Middle Aged burials in western Slovakia. We performed separate amplifications of DXZ4 repetitive satellite sequences on the X chromosome, and SRY gene - testis determined factor on the Y chromosome, using nested PCR. Our results showed that DXZ4 was amplified in the case of 23 individuals. With newly designed internal and external primer sets for SRY detection with internal PCR products in lengths of 102 bp and 85 bp we succeeded in detecting the SRY locus in 9 samples. Finally, the gender was determined in 23 individuals (14 females and 9 males). In 20 samples, the gender was determined by morphological and molecular methods. Sex determination of 17 samples using nested PCR matched the morphological one, providing evidence of the authenticity and ancient origin of the PCR amplifications. The DXZ4/SRY nested PCR method represents a useful technique in sex determination of medieval human remains and it is a critical addition to anthropological studies.

Background While gross morphological changes in the skeleton between males and females are well know, differences between sexes in the histomorphology are less known. It is important to have knowledge on the bone structure of rabbits, as this is a widely used species in biomedical research. A study was performed to evaluate the association between sex and the compact bone morphology of the femoral diaphysis in juvenile rabbits. Methods Seventeen clinically healthy 2–3 month-old rabbits (9 females, 8 males) were included in the study. The rabbits were euthanized and the right femur was sampled for analysis. 70–80 microns thick bone sections of the femoral diaphysis were prepared using standard histological equipment. The qualitative histological characteristics were determined according to internationally accepted classification systems while the quantitative parameters were assessed using the software Scion Image. Areas, perimeters, minimum and maximum diameters of primary osteons' vascular canals, Haversian canals and secondary osteons were measured. Additionally, blood plasma concentrations of progesterone, corticosterone, IGF-I, testosterone and estradiol were analyzed. Results Qualitative histological characteristics were similar for both sexes. However, variations of certain quantitative histological characteristics were identified. Measured parameters of the primary osteons' vascular canals were higher in males than for females. On the other hand, females had significant higher values of secondary osteons parameters. Differences in Haversian canals parameters were only significant for minimum diameter. Conclusion The study demonstrated that quantitative histological characteristics of compact bone tissue of the femoral diaphysis in juvenile rabbits were sex dependent. The variations may be associated with different growth and modeling of the femur through influence by sex-specific steroids, mechanical loads, genetic factors and a multitude of other sources. The results can be applied in experimental studies focusing on comparison of the skeletal biology of the sexes.

In order to develop an identification key for distinguishing between several mammalian species, bone structure of their compact bone tissue was analyzed using qualitative and quantitative characteristics. Ninety femora of adult male humans, pigs, cows, sheep, rabbits, and rats were studied. The average area, perimeter, minimum, and maximum diameter of 1863 Haversian canals and 1863 secondary osteons were measured using a digital image device. The observed data were first used to evaluate inter- and intraspecies diversity. After that, we applied a discriminant function analysis for differentiation of the species by these variables. Classification functions for investigated species give cross-validated correct classification rates for 76.17% of cases. This percentage value can be increased by integrating conclusions from the qualitative analysis.

The ryanodine receptor gene (RYR1) and the estrogen receptor gene (ESR) are the best commercially used markers for predisposition of stress susceptibility (malignant hyperthermia--MH) and increased litter size, respectively. A simplified method of simultaneous detection of MH and ESR genotypes has been developed. The method is based on simultaneous amplification of fragments of two genes by multiplex PCR and subsequent digestion of the products with two restriction enzymes. The PCR and the digestion could be performed in a single tube and all genotypes could be detected by electrophoretic separation on the same agarose gel. Thus, the development of the method can decrease the cost of the sample analysis and increase the speed and efficiency of the analysis. In our study, frequencies of mutated T allele of the RYR1 gene in Large White (LW), White Meaty (WM) and Landrace (L) were 0.11, 0.13, and 0.15, respectively. Frequencies of the preferred B allele of the ESR gene in the same breeds were 0.35, 0.26, and 0.06, respectively.

Concentrations of selected heavy metals in the femora and femoral bone structure of bank (Myodes glareolus) and common (Microtus arvalis) voles from different polluted biotopes in Slovakia (Koliňany and Novaky sites) were investigated. Length, weight, and histological structure of vole bones were also analyzed. We observed higher concentrations of lead (Pb), iron (Fe), copper (Cu), and zinc (Zn) in the bones of both species from the Koliňany site. Significant differences were observed in the concentration of Fe in bank and common voles (p

Acrylamide (AA) is one of the most common toxins in foods. Its effect on bone microstructure has not been investigated. The aim of our study was to analyze the impact of acute exposure to AA on femoral bone microstructure in mice. Adult animals were treated perorally with 2 doses of AA (E1 group, 1 mg/kg b.w.) in a 24-h period and with 3 doses of AA (E2 group, 1 mg/kg b.w.) in a 48-h period. Mice exposed to AA had smaller sizes of primary osteon's vascular canals. Secondary osteons were significantly smaller in mice from E2 group; however their increased number (from 38 % to 77 %) was identified in both E1 and E2 groups. In these groups, a higher number of resorption lacunae (from 100 % to 122 %) was also found. The values for bone volume, trabecular number were increased and that for trabecular separation was decreased in mice administered AA. Significantly higher value of bone surface was observed in mice from E1 group whereas trabecular thickness was increased in E2 group. The effect of AA on microstructure of compact and trabecular bone tissues is different. In our study, one dose of AA was used and acute effects of AA were investigated. Therefore, further studies are needed to study mechanisms by which AA acts on bone.

The aim of these studies was to compare some endocrine and non-endocrine characteristics of transgenic (carrying mammary gland-specific mWAP-hFVIII gene construct) and non-transgenic rabbits. The concentrations of corticosterone, progesterone, testosterone, estradiol, insulin-like growth factor I (IGF-I) and human factor VIII (hFVIII) in the blood plasma of adult females (9 months of age, 3rd generation transgenic animals), adult males, and young females (1-2 months of age, 4th generation of transgenic animals), as well as in the milk of lactating adult females, were analyzed by using RIA. In addition, litter size and body mass of pups born by transgenic and non-transgenic females from the 3rd generation were compared. Transgenic animals were compared with their non-transgenic siblings (the same genetic and epigenetic background). Transgenesis did not influence plasma hFVIII, but significantly increased corticosterone (in all animals), reduced IGF-I (in adult males and females), testosterone and estradiol, (in young females) and altered progesterone (increase in adult males and decrease in adult females) concentrations in blood plasma. In addition, transgenic females had higher milk concentrations of testosterone, but not progesterone or IGF-I than their nontransgenic sisters. These endocrine changes were not associated with changes in litter size. Transgenic male (but not female) pups have smaller body mass than control animals. These observations demonstrate the influence of transgenesis per se on the animal growth and endocrine system (secretion of reproductive and stress steroid hormones as well as growth factors) over four generations.

We investigated the effect of the estrogen receptor (ESR) and ryanodine receptor (RYR1) genes on total number of born (TNB), number of born alive (NBA) and number of weaned (NW) piglets in Large White (LW), White Meaty (WM) and Landrace (L) sows from six Slovak breeding farms. We found a significant effect of ESR locus on NW (P≤0.01) in LW, however, we observed a negative effect of BB genotype on the trait. In WM, positive associations of B allele with TNB, NBA, NW were found but the differences were not confirmed statistically. A highly significant effect (P≤0.01) of ESR locus on TNB (+0.62±0.18 pigs per copy of B allele), NBA (+0.65±0.18) and NW (+0.51±0.16) was identified in L breed. With RYR1 gene we found significantly higher TNB and NBA in heterozygous WM sows (+1.01±0.36 in TNB; +0.87±0.32 in NBA; P≤0.01). NBA was also significant in LW (+0.41±0.19; P≤0.05).