BackgroundNutritional manipulations during fetal growth may induce long-term metabolic effects in postnatal life. The aim of the study was to test whether combined treatment of pregnant sows with alpha-ketoglutarate and β-hydroxy-β-methylbutyrate induces additive long-term effects on skeletal system properties in the offspring.MethodsThe study was performed on 290 pigs obtained from 24 sows divided into 4 equal groups and subjected to experimental treatment during two weeks before delivery. The first group consisted of control sows, while the second group received alpha-ketoglutarate. The third group was treated with β-hydroxy-β-methylbutyrate and the fourth group underwent combined administration of alpha-ketoglutarate and β-hydroxy-β-methylbutyrate. Piglets obtained from sows were reared until slaughter age to perform morphometric, densitometric and mechanical analyses of femur. Serum evaluations of growth hormone, insulin-like growth factor-1, bone-specific alkaline phosphatase and osteocalcin were performed in newborns and 90-day old piglets; additionally, plasma amino acid concentration was measured in newborns.ResultsMaternal treatment with alpha-ketoglutarate and β-hydroxy-β-methylbutyrate significantly reduced fattening time and increased birth body weight, daily body weight gain, bone weight, volumetric bone mineral density, geometrical parameters and mechanical endurance of femur. These effects were associated with increased serum concentrations of growth hormone, insulin-like growth factor-1, bone-specific alkaline phosphatase and osteocalcin. Furthermore, alpha-ketoglutarate and β-hydroxy-β-methylbutyrate administered solely or in combination significantly increased plasma level of 19 amino acids.ConclusionsHormonal and amino acid evaluations in pigs indicate additive effects of AKG and HMB on systemic growth and development; however, determination of bone properties has not shown such phenomenon.

The aim of the study was to evaluate interrelationships between final body weight, and morphometric, densitometric, and mechanical properties of the mandible in 6-month-old Polish Large White pigs exposed to dexamethasone and nanocalcium. The study was performed on 27 males, castrated on the 28 th d after weaning, and reared until the age of 6 months, after which the animals were slaughtered, and the mandible was obtained. The pigs were divided into four experimental groups: animals given per os nanopartical calcium, animals injected with dexamethasone, animals given both nanopartical calcium per os and dexamethasone injections, and animals injected with placebo. After the slaughter, morphological properties of the mandible such as bone weight and length were determined. Using computed tomography technique, volumetric bone mineral density (vBMD) of the cortical bone (Cd), mean volumetric bone mineral density (MvBMD), and total bone volume (Bvol) of whole mandible were measured. Areal bone mineral density (BMD) and bone mineral content were evaluated with the use of dual-energy X-ray absorptiometric method. Using three-point bending test, mechanical parameters such as maximum elastic strength (Wy) and ultimate strength (Wf) of mandible were estimated. Pearson's correlation coefficient (r) was determined between all the investigated variables. The obtained results showed a significantly positive correlation between body weight and mandible weight, mandible length, Bvol, Cd, BMD, BMC, Wy, and Wf. However, statistically insignificant correlations of MvBMD and body weight, mandible weight, mandible length, and Bvol were observed. Furthermore, Bvol and Cd were not found to be significantly correlated. In conclusion, this study showed numerous positive correlations between final body weight and densitometric, morphometric, and mechanical properties of the mandible. This bone of pigs may be used as an attractive model for further investigation on metabolic response of the skeleton to physiological, nutritional, toxicological, and pharmacological factors influencing bone tissue metabolism.

ABSTRACT. The aim of the study was to determine interrelationships between bone tissue metabolism indices and morphological, biomechanical and densitometric properties of hard dental tissues. First primary maxillary incisor from 6-month-old pigs (N=27) was evaluated in terms of weight and length. Mean volumetric tooth mineral density, total tooth volume, enamel total volume, enamel volumetric mineral density, dentine total volume and dentine volumetric mineral density were estimated with the use of quantitative computed tomography and micro computed tomography techniques. Tooth mineral density and tooth mineral content were evaluated with the use of dual-energy X-ray absorptiometry. Microhardness of enamel was measured using Vicker's test. Evaluations of total calcium, ionized calcium, magnesium, phosphorus, alkaline phosphatase, bone alkaline phosphatase, osteocalcin, C-terminal telopeptide of type-I collagen (CTX), insulin-like growth factor-1, growth hormone and parathyroid hormone were performed in plasma and serum samples. Pearson's correlation coefficients were determined between all the investigated variables, and P<0.05 was considered as statistically significant. The obtained results have shown mainly mutual dependences between biochemical indicators of bone metabolism. Evaluation of CTX concentration in serum of pigs has shown the highest predictive value in relation to morphological, densitometric and biomechanical properties of teeth. KEY WORDS: bone turnover marker, densitometry, quantitative computed tomography, swine, tooth.

The evaluation of clinical relevance in this research is crucial to simplify the transfer of knowledge from research by materials engineering into practice in dentistry.

BackgroundCaries, enamel hypoplasia, molar incisor hipomineralization, amylogenesis imperfecta, dentine dysplasia, hypophosphatasia and other dental disorders lead to tooth mineralization disturbances and structural abnormalities, decreasing masticatory organ functions. Dental disorders in sheep can lead to premature slaughter before they have attained final stage of their reproductive life and induce economic loss due to high flock replacement costs. Growth rate, health status and meat quality of sheep depends on tooth properties and quality determining in large extent efficiency of the masticatory apparatus and initial food break up. Considering lack of basic anatomical and physiological data on teeth properties in sheep, the aim of the study was to evaluate morphometric, densitometric and mechanical traits of deciduous mandibular incisor, canine and the second premolar obtained at the slaughter age of 5 months of life.ResultsThe obtained results have shown the highest values of weight, total tooth volume, enamel volume and dentine volume in second premolar. Morphometric and mechanical parameters of incisors reached the highest values in first incisor and decreased gradually in second and third incisor, and in canine. Densitometric measurements have not revealed significant differences of the volumetric tooth mineral density in hard dental tissues between the investigated teeth.ConclusionsIn conclusion, proposed methodological approach is noninvasive since the deciduous teeth undergo physiological replacement with permanent teeth. Deciduous teeth can be easy collected for analyses from large animal population and may reflect mineral status and metabolism resulting from postnatal growth and development of the whole flock. In individual cases, evaluation of properties of deciduous teeth may serve for breeding selection and further reproduction of sheep possessing favorable traits of teeth and better masticatory system functions.