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The influence of sex on bone mineral density (BMD) and the bone mineral content (BMC) have been analysed in selected bones of the thoracic and pelvic limbs of African ostriches. The examination was conducted with the use of a densitometer, using the technology of affinited beam of X-ray and the programme for animal research. It was shown that the analysed bones of ostrich skeleton differed significantly regarding the BMD and BMC. Significantly higher values of both parameters were recorded in case of the bones of the pelvic limb in comparison with the bones of the thoracic limb. A central part of the shaft of the tibio-tarsal bone and its proximal end (the pelvic limb) were characterised by the highest values for both BMD and BMC, whereas for the ulnar and radial bones (the thoracic limb) the lowest values were obtained. The study also demonstrated that males showed a significantly higher BMD and BMC values than females referring to the pelvic bones, i.e. the tibio-tarsal bone. For further study aiming at monitoring changes in BMD and BMC during the growth and development of ostriches from hatching till the 14th month of life, the use of densitometer intravitally is recommended.
Research studies on the development of the cardiovascular system and its formation during embryologic development have been conducted for a long time. However, such studies have only gained a significant interest less than two decades ago. This can be related to the introduction of immunohistochemical methods, in which endothelium cell markers and their precursors as well as smooth muscle cell markers have been applied, lining the interior surface of a blood vessel wall of a larger diameter. In the process of coronary blood vessel formation two main mechanisms are involved: vasculogenesis and angiogenesis. The formation of vessels occurs in several stages. First a monolayer of endothelial cells begins sprouting to form tubes. These are then transformed into capillaries, veins and arteries.
Methods for the evaluation of the parameters of bone tissue and their characteristics are presented. The development of modern methods and their possible application in veterinary orthopedic diagnosis is discussed. Primarily computerized assisted analysis of bone structure images on the radiograph are described.
The bone mineral density (BMD) and the bone mineral content (BMC) in the bone tissue of the bilateral first phalanges of horses’ thoracic limbs were analysed. The research material consisted of isolated pastern bones derived from 22 horses. The research was conducted with the use of a Norland model Excell Plus densitometer (Fort Atkinson WI, USA), using affinited beam X-ray technology and an animal research programme (Research Scan, 3.9.6. version) at the following parameters: scanning resolution of 1.5 x 1.5 mm, scanning speed 60 mm/s. The differences between BMC and BMD values in bilateral first phalanges in the thoracic limbs in horses were found to be nonsignificant. It also appeared that there are statistically significant positive correlations between values of the left and right bone of both analysed variables.
The aim of the study was to compare densitometric and geometric parameters of the proximal phalanges in forelimbs of Wannblood and Coldblood horses, at 15%, 50%, and 85% of the bone proximal length. Peripheral quantitative computed tomography was used to analyse the structure of phalanges. The following parameters were determined: bone mineral content, volumetric bone mineral density, total bone area, trabecular area, cortical area, cortical thickness, periosteal circumference, endocortical circumference, and strength strain index. The most significant differences between pastern bones in thoracic limbs of the horses were visible in the proximal and distal metaphyseal parts, for instance, at 15% and 85% of the bone length, respectively. Statistical analysis showed that at 15% of the bone length, total bone area, trabecular area, periosteal circumference, and endocortical circumference were significantly higher in Warmblood horses. At the mid-shaft, volumetric bone mineral density and endocortical circumference were significantly higher in Coldblood horses. At 85% of the bone length, volumetric bone mineral density, total bone area, trabecular area, periosteal circumference, and endocortical circumference were significantly higher in Coldblood horses.
Hemivertebra is a kind of changed vertebra in the spine characterized by uneven vertebral body formation, which can cause curvature of the spine. It is an inherited congenital defect found in both humans and animals. This defect occurs predominantly in brachycephalic breeds, such as French Bulldogs, English Bulldogs, Pugs, and Boston Terriers. The aim of the study was to analyze the prevalence and the degree of development of this pathology in a selected population of French Bulldogs (n = 58), English Bulldogs (n = 9), and Pugs (n = 14). The occurrence of hemivertebrae was evaluated on X-rays performed in lateral and ventral-dorsal projections. Depending on the dog’s size, the voltage ranged between 76 and 54 kV, and the current ranged between 16 and 20 mAs. Hemivertebrae were found in 73% of dogs. The largest number of them were found in French Bulldogs and the fewest in Pugs. In 14% of dogs with confirmed malformation, neurological symptoms occurred. This study indicates that hemivertebrae is a developmental disorder most common in French Bulldogs, and the least frequent in Pugs. However, Pugs, more often than other breeds evaluated here, were diagnosed with hemivertebrae causing neurological disorders. In the thoracic segment of the spine, a hemivertebra usually affects Th5, Th6, Th7, Th9, and Th10. Due to the large prevalence of wedge-shaped vertebrae in brachycephalic breeds, radiographic examination for the presence of this defect is recommended in breeding dogs. Further uncontrolled proliferation of this defect may permanently damage the gene pool of these breeds.
The aim of this research was to evaluate the existence of sexual dimorphism in the horse larynx as far as morphology, absolute and relative dimensions, and the weight of the organ, were concerned. The material consisted of the larynxes, taken from 20 adult horses of both sexes. The larynxes were examined morphologically, weighed, and linear, angular, and surface measurements were taken. It was found that horse larynxes, were characterised by a practically unnoticed sexual dimorphism. The weight and size parameters of the larynxes were not directly connected with the weight of the whole body of the animal.
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