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1.
OBJECTIVE: To determine those bones in the distal aspect of the limbs of Greyhounds with fatigue fractures that have the greatest left-to-right differences in bone-mineral density (BMD). SAMPLE POPULATION: Limbs obtained from 20 Greyhounds. PROCEDURE: Dual-energy x-ray absorptiometry (DXA) of the distal aspect of each limb and isolated bones from 10 dogs with a fracture of the central tarsal bone (CTB) of the right pelvic limb was performed. High-resolution scanning was performed on excised bones, and BMD measurements of CTB also were obtained from limbs of dogs without a CTB fracture. RESULTS: The BMD of the accessory carpal bone and calcaneus was not significantly different from the BMD of those bones in the contralateral limb. Although BMD of the CTB of the entire right pelvic limb and isolated bones from dogs with a CTB fracture was lower, compared with values for the entire left pelvic limb, values for isolated CTB from dogs without a CTB fracture were not significantly different. Metacarpal or metatarsal and thoracic or pelvic limb significantly affected BMD for measurements of the entire limb and isolated bones. Left-to-right differences in BMD were greatest for metacarpal 5. CONCLUSIONS AND CLINICAL RELEVANCE: Asymmetric adaptive remodeling of metacarpal 5 can be detected by DXA. The potentially confounding effects of CTB fracture and unknown racing history made it difficult to interpret BMD changes in the CTB of these specimens. Densitometry could be developed as an in vivo assessment for risk of fractures in racing Greyhounds.  相似文献   

2.
An outbreak of the asymmetric hindquarter syndrome was investigated in a Western Australian piggery. The condition was manifested as asymmetry of the hindquarter, particularly the semitendinosis, semimembranosis and biceps femoris muscles. The gait of affected animals was not noticeably altered, despite an obvious disparity in size between normal and affected limbs. Histologically, muscular degenerative and dystrophic changes were seen but were not present in all undersized muscles and were occasionally present in macroscopically normal muscles. All 7 affected pigs whose breeding history could be traced were sired by the same boar. The condition adversely affected conformation and resulted in down-grading of carcases.  相似文献   

3.
Radiographs of 14 dogs with ectrodactyly of the forelimb were evaluated and the defect classified according to the site of division of the longitudinal axis of the paw. The majority of separations occurred between metacarpal bones one and two, although separations were also noted between metacarpal bones two and three, two and four, and three and four. Other lesions noted in affected limbs included digit contracture, digit aplasia, metacarpal hypoplasia and metacarpal fusions. Bilateral involvement was noted in only one of 14 cases. No breed or sex predisposition was found and there was equal involvement of the left and right limbs.  相似文献   

4.
Humpy back, a disease of Merino sheep in western Queesland, occurs during mustering for shearing. It is usually seen in summer 6-10 weeks after substantial rainfall and is thought to be caused by the ingestion of a toxic plant. The disease is characterised clinically by a short-stepping, stilted gait of the hind limbs, followed by lowering of the head, arching of the back and inability to continue walking. Histopathological examination of 8 cases from 5 properties revealed a Wallerian degeneration of the white matter throughout the length of the spinal cord with the ventral and lateral columns most severely affected. A similar degenerative change was seen in the posterior cerebellar peduncles of 3 of the sheep. A more severe hind limb incoordination with more extensive degeneration of the white matter of the spinal cord, medulla and cerebellum was seen in a case of humpy back of two years duration. Similar, but much milder, spinal cord lesions were found in apparently unaffected sheep from the same group as the sheep affected with humpy back on 2 properties. Severe myodegeneration of hind limb muscle groups was seen in 3 affected sheep. It was thought to be associated with the long rail journey (1500 km) to the laboratory after the sheep were affected in the field.  相似文献   

5.
Morphology of the modern cetaceans represents the results of adaptation of the ancestral terrestrial mammals to aquatic life through their evolutional processes. Some of the primitive fossil cetaceans are known to have both fore and hind limbs, whereas the pelvic bones of modern cetaceans are, in general, a pair of slender rod-like structures within the abdominal wall muscles just anterior to the anus with no articulations to the axial skeleton in both sexes. It is interesting and important to consider the causes and processes of how the hind limbs were lost and how the pelvis was reduced during the process of adaptation. In the present study, we tried to evaluate the topography and function of rudimentary pelvic bones of the finless porpoise (Neophocaena phocaenoides), one of the members of the odontocete cetaceans, with special references to the structures around the pelvic bones. Some soft tissues such as M. ischiocavernosus relating to the pelvic bone are transformed following the drastic reduction of the pelvis. This transformation tells us that the cetaceans adapted to the aquatic life during evolutional processes chose the tail flukes driven by the powerful trunk muscles for locomotion, instead of modifying the hind limbs into hind flippers as seen in pinnipeds. On the other hand, it is evident that a function of the pelvic bones of the male finless porpoise was supporting the penis as those of terrestrial mammals. It is noteworthy that the morphological features of the ancestral terrestrial mammals can be traced when they are carefully compared with those of the finless porpoise.  相似文献   

6.
Diagnostic guidelines were established for progeny testing of hereditary bovine syndactyly. Through the use of superovulation and embryo transfer, 139 fetuses were recovered at 50 to 77 days gestation. Normal (+/+, +/sy) and syndactylous (sy/sy) anatomy of Holstein fetuses was defined, and the accuracy of macroscopic versus microscopic limb diagnosis was assessed. Chondrification and ossification differences between normal (+/+, +/sy) and syndactylous (sy/sy) fetuses were only age-related. Normal (+/+, +/sy) fetal limbs differed from normal (+/+, +/sy) adult bovine limbs in two ways. Fetal metacarpal and metatarsal III and IV bones were not fused, and fetal metacarpal and metatarsal II and V bones often extended up to three-fourths the length of metacarpal and metatarsal III and IV bones. In syndactylous (sy/sy) fetuses, synostosis asymmetries occurred within and between fetal limbs, and between fetuses, representing variable gene expressivity. Synostosis pattern within limbs did not correspond with those of the adult bovine; the second phalangeal pair was synostotic most frequently in the fetus, followed by the first, and then the third pair. Synostosis patterns between fetal limbs agreed with those of the adult; there was a right-left and front-rear limb gradient. Partial synostoses occurred sporadically in all three paired phalanges. Those of the first and third pair always involved the tip closest to the second phalangeal pair. A unique example of variable gene expressivity occurred in one syndactylous fetus. Both front limbs were syndactylous, while both rear limbs were normal grossly. Microscopically the right rear limb was normal while the left rear limb consisted of closely apposed phalangeal blastemata without coalescence.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
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.  相似文献   

8.
A safe, non-invasive method for the accurate measurement of bone mineral content in the third metacarpal bone of the horse is described. The technique involves scanning the bone with a single photon beam from an Americium-241 source. Data were obtained from the excised metacarpal bones from both forelimbs of 50 normal and seven lame horses. Measurements were made in vivo on eight normal and seven lame horses and on one experimental horse with osteopenia induced by partial weightlessness in a flotation tank. In the normal horses bone mineral content altered with age, particularly in the first six months of life. There were also differences according to the site of scanning on the metacarpus. The contribution of the splint bones to the total bone mineral content was less than 2 per cent distal to the mid-point of the metacarpus, but in the proximal shaft it increased to 12 per cent. No significant differences were noted either between right and left limbs, or between male and female animals. A reduction in bone mineral content was demonstrated in the affected leg of horses with chronic lameness and with osteopenia induced by weightlessness. The bone mineral content (g/cm) correlated well with the ash content (mg/100 mg dry bone weight), the specific gravity and the apparent transverse velocity of ultrasound (m/sec) through the bone. A measure of bone mineral density (g/cm3) was calculated from the bone mineral content and cross sectional area of the bone to overcome the individual differences in size of the metacarpus.  相似文献   

9.
A total of 20 cases of disproportionate calves on Japanese Brown cattle were examined morphologically. Investigation of 5 affected calves revealed that the insufficiency of endochondral ossification was confined only to the long bones of the limbs and was not accompanied by other associated changes. On the basis of the histological changes of epiphyseal plate and the affected site, this condition may be called chondrodysplasia of the rhizomelic type. Therefore, this disorder was defined as a bovine dwarfism. From three dimensional image analysis and histological changes of the tibial proximal portion in the other 15 cases, deformity and shortness of the tibia were related to the state of distribution and the degree of damages of the epiphyseal plate. In the affected cartilage matrix, cystoid degeneration, fibrous striation, bone spicule, necrotic foci and rent were found. Inadequate metachromasia suggests the abnormal staining of sulfated glycosaminoglycans and alcian blue stainability may be attributable to the abnormal interactions between proteoglycan and other matrix components. At the interface of cartilage and bone, irregular calcification, fibrotic scar and sealing by osseous tissue with relation to vascularity were found. These changes in this study indicated the failure of modeling on the epiphyseal plate, showing disturbance of chondrocytic differentiation and abnormal formation of the matrix.  相似文献   

10.
Reasons for performing study: There is limited information on magnetic resonance imaging (MRI) findings in the carpus and proximal metacarpal region of lame horses. Objectives: To document MRI findings in horses with lameness localised to the carpus and/or proximal metacarpal region. Methods: Clinical records of horses that underwent MRI of the carpus and/or proximal metacarpal region at the Animal Health Trust between January 2003 and September 2010 were reviewed. Magnetic resonance images of all horses and available radiographs, ultrasonographic and scintigraphic images were assessed. When possible, MRI findings were related to the results of other diagnostic imaging techniques. Results: Seventy‐two MR studies of 58 lame limbs in 50 horses from a broad range of work disciplines and ages were reviewed. The most commonly detected primary abnormality was decreased signal intensity in T1‐ and T2‐weighted images in the medial aspect of the carpal bones and/or the proximomedial aspect of the metacarpal bones (n = 29). Nine horses had syndesmopathy between the second and third metacarpal bones. In 6 horses the primary abnormalities were identified in the palmar cortex of the third metacarpal bone (McIII). Significant abnormalities of the suspensory ligament (SL) with associated lesions in the adjacent palmar cortex of the McIII were seen in 4 limbs. Ligament and associated osseous abnormalities between the second and third carpal bones and second and third metacarpal bones were detected in 4 limbs. Conclusions and potential relevance: Magnetic resonance imaging enabled diagnosis of a variety of lesions not detected by conventional imaging in horses from a wide range of work disciplines. The distribution of injury types differed considerably from previous studies.  相似文献   

11.
Many studies have described the effects of exercise restriction on the mammalian skeleton. In particular, human and animal models have shown that reduction in weight bearing leads to generalised bone loss and deterioration of its mechanical properties. The aim of this study was to assess the effect of prolonged exercise restriction coupled with heavy calcium demands on the micro-structural, compositional and mechanical properties of the avian skeleton. The tibiae and humeri of 2-year-old laying hens housed in conventional caging (CC) and free-range (FR) housing systems were compared by mechanical testing and micro-computed tomography (μCT) scanning. Analyses of cortical, cancellous and medullary bone were performed.Mechanical testing revealed that the tibiae and humeri of birds from the FR group had superior mechanical properties relative to those of the CC group, and μCT scanning indicated larger cortical and lower medullary regions in FR group bones. Cancellous bone analysis revealed higher trabecular thickness and a higher bone volume fraction in the FR group, but no difference in mineral density. The biomechanical superiority of bones from the FR group was primarily due to structural rather than compositional differences, and this was reflected in both the cortical and cancellous components of the bones. The study demonstrated that prolonged exercise restriction in laying hens resulted in major structural and mechanical effects on the bird skeleton.  相似文献   

12.
A retrospective study was undertaken to record the occurrence and pattern of long bone fractures, and the efficacy of Intramedullary (IM) Steinmann pin fixing in growing dogs. All the records of growing dogs during a 10-year-period were screened to record the cause of trauma, the age and sex of the animal, the bone involved, the type and location of the fracture, the status of fixation, alignment, maintenance of fixation and fracture healing. The results were analysed and comparisons were made between growing dogs with normal and osteopenic bones. Among the 310 cases of fractures recorded, the bones were osteopenic in 91 cases (29%). Minor trauma was the principal cause of fracture in dogs with osteopenia (25%), and indigenous breeds were most commonly affected (38%). Fractures in dogs with osteopenic bones were most commonly recorded in the age group of 2-4 months (53%), whereas fractures in normal dogs were almost equally distributed between 2 and 8 months of age. Male dogs were affected significantly more often in both groups. In osteopenic bones, most fractures were recorded in the femur (56%), and they were distributed equally along the length of the bone. Whereas in normal bones, fractures were almost equally distributed in radius/ulna, femur and tibia, and were more often recorded at the middle and distal third of long bones. Oblique fractures were most common in both groups; however, comminuted fractures were more frequent in normal bones, whereas incomplete fractures were more common in osteopenic bones. Ninety-nine fracture cases treated with IM pinning (66 normal, 33 osteopenic) were evaluated for the status of fracture reduction and healing. In a majority of the cases (61%) with osteopenic bones, the diameter of the pin was relatively smaller than the diameter of the medullary cavity (<70-75%), whereas in 68% of the cases in normal bones the pin diameter was optimum. The status of fracture fixing was satisfactory to good in significantly more osteonormal (59%) than osteopenic dogs (42%). Fracture healing, however, was satisfactory in significantly more cases with osteopenic than normal bones. The appearance of callus was relatively early and the amount of bridging callus was relatively large in greater number of osteopenic bone fractures. Mal-union and non-union were recorded more often in osteopenic cases than in normal cases. However, the incidence of bone shortening and osteomyelitis was significantly higher in normal bones than in osteopenic bones.  相似文献   

13.
Elena  Mozos  DVM  PhD  Manuel  Novales  DVM  PhD  Pedro J.  Ginel  DVM  PhD  José  Pérez  DVM  PhD  Roy R.  Pool  DVM  PhD 《Veterinary radiology & ultrasound》2002,43(2):132-137
Clinicopathological findings are described for a unique skeletal pattern of osteochondromatosis (syn. multiple osteochondromas) in three crossbred littermate dogs. Multiple nonpainful bilaterally symmetric skeletal lesions arose from focal semiannular and annular areas of periosteal thickening on the cortical surface of the metaphyses and diaphyses of long bones. Flat bones of the skull were spared. In radiographs osteochondromas in different stages of evolution were apparent. Grossly there were smoothly contoured, nodular subperiosteal masses of dense fibrocartilaginous and osseous tissue that were continuous with and overlying apparently normal but thin trabeculae of cancellous bone. Cortical compacta was attenuated or absent beneath exostoses. In histologic sections of the cartilage-capped exostoses a hyperplastic periosteum formed a focal semiannular or annular cap of proliferative hyaline cartilage tissue that underwent endochondral ossification and replacement by cancellous bone at its base. Intertrabecular spaces in the cancellous bone of exostoses were filled with fibro-osseous and hematopoietic tissue. A hereditary origin was suspected for the osteochondromas. Origin of some osteochondromas as semiannular or annular perturbations of the perichondrial ring of metaphyseal physes of long bones likely contributed to limb shortening and a pattern of billaterally symmetric angular limb deformities of all limbs as occurs in some children affected by osteochondromatosis.  相似文献   

14.
ObjectiveTo investigate the effects of habituation and isolation on mechanical nociceptive thresholds in pigs at the pelvic limbs and at the tail.Study designProspective randomized multifactorial study.AnimalsThirty-two healthy castrated male (experiment 1), and 12 castrated male and 12 female (experiment 2) Danish Landrace × Yorkshire pigs, weighing 63.5 ± 0.8 kg and 55.4 ± 0.6 kg (the mean ± SD, experiment 1 and 2, respectively).MethodsMechanical nociceptive thresholds were quantified with a von Frey anesthesiometer applied to two distinct anatomical regions (tail and pelvic limbs). Pigs receiving the mechanical challenge in the pelvic limbs were tested inside a cage, whereas pigs exposed to stimuli at the tail region were tested in an open arena. For both experiments, the effect of familiarity to the procedure was evaluated by comparing thresholds of nociception in habituated versus naïve pigs. The presence of a companion animal was also evaluated in pigs receiving stimuli at the pelvic limbs.ResultsPigs tested inside the cage were affected by the habituation to the procedure as indicated by the increase in willingness and time spent by the animals in the test cage. This effect was reflected in the lower mechanical nociceptive thresholds (medians with 25–75 percentiles) recorded for familiar pigs compared with naïve animals [495 g (302–675) versus 745 g (479–1000), respectively; p = 0.026]. Mechanical nociceptive thresholds measured at the tail of the pigs in the open arena were not affected by the familiarity of the animals with the experimental procedure.Conclusions and clinical relevanceThe current results reiterate the value of habituation in research involving animal behaviour. Further characterization of the methodology is needed to allow its application in the evaluation of clinical conditions in pigs.  相似文献   

15.
A group of Leghorn and a group of broiler chicks were reared from day old. At two weeks old a metallic marker was placed unilaterally in the mid-diaphysis of the femur, tibiotarsus and tarsometatarsus of every chick. After the operation the limbs were radiographed. After a period of growth the birds were killed and the radiographs repeated. Measurements from the radiographs enabled the calculation of the rate of growth at the bone extremities. There were metaphyseal defects indicative of dyschondroplasia present in some of the broiler bone extremities, these bones were considered as a separate group. When the Leghorn and normal broilers were compared there was a significant reduction in the proportion of growth in the proximal tibiotarsus of the broilers. The dyschondroplastic bone extremities in broilers demonstrated a reduction in the proportional growth rate compared with normal extremities.  相似文献   

16.
In this case report, we describe a tawny owl chick (Strix aluco) coming from a Wild Fauna Recovery Center with multiple congenital malformations in the limbs. The animal was unable to fly and showed marked malnutrition and poor general appearance. Physical, radiologic, and anatomic examinations showed osseous malformations including dislocation of radius and carpometacarpus with abnormal nonfunctional fixation of ligamentum propatagialis, absence of most parts of the bones of the manus in both wings, and twisted nonfused left tarsometatarsus with marked griphosis of digits. Routine toxicologic and pathologic examinations did not reveal a specific etiology.  相似文献   

17.
Tendon/ligament mineralization is recognized in horses but information regarding its clinical significance is limited. The aims of this observational study were to report the structures most commonly affected by ultrasonographically detectable mineralization and, for these, determine frequency of diagnosis and key clinical features. Cases presented at our hospital in April 1999–April 2013 and September 2014–November 2015 were included: a total of 27 horses (22 retrospective, five prospective). Mineralizations were most common in deep digital flexor tendons (10) and suspensory ligament branches (eight), representing 10% and 7% (estimated), respectively, of horses diagnosed with injuries to these structures during the study. Two deep digital flexor tendon and three suspensory ligament branch cases showed bilateral mineralization. Deep digital flexor tendon mineralization was restricted to the digital flexor tendon sheath, most commonly in the proximal sheath (±sesamoidean canal), and seven of 10 cases involved hindlimbs. Suspensory ligament branch mineralization was visible in the same ultrasound window as the proximal sesamoid bones in 10/11 limbs and six of eight cases involved forelimbs. Previous corticosteroid medication was a feature of one deep digital flexor tendon and one suspensory ligament branch case. Mineralization was associated with lameness in some but not all limbs. Mineralized foci within the deep digital flexor tendon preceded hypoechoic lesion formation in two limbs. Of the cases with deep digital flexor tendon or suspensory ligament branch injury only, one of three and two of three cases, respectively, became sound. Findings indicated that tendon/ligament mineralization can be associated with lameness in some horses, but can also be an incidental finding.  相似文献   

18.
This report describes a case of hypertrophic osteopathy in an approximately three years old male roe deer (Capreolus capreolus). The hunter reported that the animal was apparently healthy and showed no signs of movement imparities. At dissection, a combination of a lung abscess with bony swellings at the distal parts of the limbs was observed. Further investigation revealed that the bony swellings were caused by a severe periosteal hyperosteosis at the diaphyses of the digital phalanges, metacarpal and metatarsal bones. The periosteal new bone was characterized by the formation of coralliform osteophytes, typically seen in cases of hypertrophic osteopathy. As usual in animals with hypertrophic osteopathy, the pathological changes in this roe deer developed secondary to a intrathoracic lesion (lung abscess).  相似文献   

19.
Osteochondritis dissecans of the sagittal ridge of the third metacarpal and metatarsal bones was diagnosed in 8 horses during an 18-month period. Seven of the horses were less than or equal to 2 1/2 years old. Synovial distention of the affected fetlock joints and a pain response to fetlock flexion were typical findings. Lameness predominated in 1 limb at a trot, although fetlock flexion frequently elicited lameness in other affected limbs. Radiography revealed bony lesions (flattening, erosion, or fragmentation) of the sagittal ridge in at least 2 fetlock joints in all horses. The onset of signs was not correlated with the severity of radiographic changes in all horses.  相似文献   

20.
When offered a selection of food items, bearded vultures Gypaetus barbatus in southern Africa chose bones in preference to meat or to feeding from a fleshed carcass. Once a carcass had been stripped of soft tissue by Gyps vultures, bearded vultures disarticulated sections or individual bones (depending on the size of the dead animal) in the order: limbs, ribs, vertebrae, skull. Their overall diet was estimated as 70% bone with marrow, 25% meat and 5% skin. This diet is about 15% higher in energy than an equivalent mass of meat. Of 683 identified prey items from five sources of data, over 80% consisted of domestic livestock; about 60% of this was sheep and goats. Even birds nesting within conservation areas derived more than half of their food from domestic stock which they found by foraging over adjacent commercial and subsistence farming areas. Bearded vultures obtain all their food by scavenging, and reports of attacks on live animals and even humans are rejected.  相似文献   

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