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1.
It has been demonstrated in animal studies that prenatal administration of β‐hydroxy‐β‐methylbutyrate (HMB, metabolite of leucine) influences general growth and mechanical endurance of long bones in newborn offspring in sex‐dependent manner. The present experiment was conducted to evaluate the effect of HMB treatment of pregnant sows on bone development in offspring at weaning. From 70th day until the 90th day of gestation, sows received either a basal diet (n = 12) or the same diet supplemented with HMB (n = 12) at the dose of 0.2 g/kg of body weight/day. Femora obtained from six males and females in each group weaned at the age of 35 days were examined. Maternal HMB treatment significantly enhanced body weight and changed bone morphology increasing femur mechanical strength in both sexes. Maternal HMB supplementation also elevated bone micro‐ and macroelement concentrations and enhanced content of proteoglycans in articular cartilage. Based on the obtained results, it can be concluded that maternal HMB supplementation in the mid‐gestation period significantly accelerated bone development in both sexes by upregulation of a multifactorial system including leptin and osteoprotegerin. However, the sex (irrespective of the HMB treatment) was the factor which influenced the collagen structure in cartilages and trabecular bone, as demonstrated both by the Picrosirius red staining and performed analysis of thermal stability of collagenous tissues. The structural differences in collagen between males and females were presumably related to a different collagen maturity. No studies conducted so far provided a detailed morphological analysis of bone, articular cartilage, growth plate and the activities of the somatotropic and pituitary–gonadal axes, as well as leptin/osteoprotegerin system in weaned offspring prenatally treated with HMB. This study showed also the relationship between the maternal HMB treatment and bone osteometric and mechanical traits, hormones, and growth and bone turnover markers such as leptin, osteoprotegerin and insulin‐like growth factor‐1.  相似文献   

2.
R J Julian 《Avian diseases》1985,29(3):854-866
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3.
Ultrasonographic examination of the tarsus was performed on four clinically and radiographically normal limbs of adult horses. Particular attention was paid to the articular cartilage surfaces of the trochlear ridges of the talus and the distal intermediate ridge of the tibia. Two separate measurements of articular cartilage thickness were acquired from a longitudinal view at each site. Anatomy was confirmed with post mortem dissection. Ultrasonography was found to be a practical method for imaging the articular cartilage over the trochlear ridges of the talus and distal intermediate ridge of the tibia. The cartilage appeared as a hypoechoic band overlying the hyperechoic subchondral bone. The mean cartilage thickness over the lateral and medial trochlear ridges of the talus and the distal intermediate ridge of the tibia were 0.57 mm, 0.58 mm and 0.7 mm respectively. These measurements may have value for comparison to thickened cartilage and lesions of osteochondrosis and abnormally thinned cartilage of osteoarthritis. Ultrasound examination was not helpful in evaluating the proximal and distal intertarsal and tarsometatarsal joints, the close proximity of the articular surfaces obscured visualization of the articular cartilage.  相似文献   

4.
OBJECTIVE: To describe the cancellous bone architecture of the head and neck of the femur in healthy dogs by use of automated histomorphometry techniques in conjunction with histologic grading of articular cartilage. ANIMALS: 30 mature male dogs with healthy coxo-femoral joints PROCEDURE: Dogs were 1.5 to 4 years old and weighed 27 to 37 kg. Computer images of fine-detail radiographs of 100-microm-thick coronal and transverse plane sections of the head and neck of the femur (14 dogs) were analyzed by use of histomorphometry software. Statistical comparisons among histomorphometric indices of 4 regions were performed. Histologic preparations of coronal and transverse plane sections of femoral head articular cartilage (16 dogs) were graded. Median grades for lateral, medial, cranial, and caudal halves of the femoral head articular cartilage were determined. RESULTS: Bone volume/total volume, trabecular thickness and number, and bone surface/total volume were significantly higher in the femoral head than in the femoral neck. Anisotropy (trabecular alignment) and trabecular separation were significantly higher in the femoral neck than in the femoral head. Anisotropy was significantly higher in the caudal half of the femoral neck than in the cranial half. Cartilage had histologic grades indicating health without significant differences among lateral, medial, cranial, and caudal halves of femoral head cartilage. CONCLUSIONS AND CLINICAL RELEVANCE: A predictable cancellous architecture in the head and neck of the femur is associated with healthy cartilage.  相似文献   

5.
In mammals, the release from growth‐inhibiting conditions results in catch‐up growth. To investigate animal evidence for whether prenatal dexamethasone (DEX) treatment leads to the development of growth restriction especially reduced mineralization of skeleton, and release from it leads to the phenomenon of catch‐up, piglets were prenatally exposed to DEX (3.0 mg/sow per day?2) during the last 24 days of prenatal life and tested further in two different ways: discontinued at birth and continued administration of DEX (0.5 mg/kg day?2) to piglets through 30 days of neonatal life. Using dual energy X‐ray absorptiometry methods, bone mineral density (BMD) and bone mineral content (BMC) were measured. The three‐point bending test was applied to determine the mechanical properties of the bones. Furthermore, geometric properties of the bones were assessed. Serum concentration of osteocalcin (OC) was determined. Histomorphological analysis of the ribs was also performed. The consequences of neonate DEX treatment and in utero DEX exposure were reflected in a dramatic decrease of BMD, BMC and blood serum OC concentration and geometric parameters of piglets’ bones. Prenatal action of DEX during the last 24 days of pregnancy resulted in continued neonatal modification of bone tissues, thus diminishing bone quality, and negatively influenced structural development and mechanical properties, finally increasing the risk of fractures of ribs and limb bones. Prenatal DEX treatment limited to the last 24 days of foetal life did not reduce the term birth weight and the growth of suckling piglets followed up to 30 days of neonatal life, and catch‐up in bone mineralization did not occur.  相似文献   

6.
OBJECTIVE: To describe cancellous architecture of the proximal portion of the femur in dogs with osteoarthritis. ANIMALS: 30 dogs with coxofemoral osteoarthritis. PROCEDURE: All dogs had femoral head and neck excision or total hip arthroplasty. Histomorphometry software was used to analyze computer images of 100-microm-thick coronal and transverse plane sections of the head and neck of the femur. Histologic preparations of coronal and transverse sections of articular cartilage were graded. RESULTS: Bone volume/total volume, trabecular thickness, trabecular number, and bone surface/total volume were significantly higher in the femoral head than femoral neck. Trabecular alignment (anisotropy) and separation were significantly higher in the femoral neck than femoral head. Anisotropy was significantly increased in the medial portion of the femoral head in the coronal plane and in the cranial portion of the femoral neck in the transverse plane, compared with healthy dogs. The medial half of femoral head cartilage that overlies the proximomedial cancellous bone region had significantly more degraded cartilage than the lateral half. Histologic grades for cranial and caudal halves of femoral head articular cartilage were similar. CONCLUSIONS AND CLINICAL RELEVANCE: Most findings were similar to those in healthy dogs. Greater trabecular alignment in the proximomedial region of the femoral head and craniolateral region of the femoral neck in dogs with osteoarthritis suggests an altered transfer of load through the coxofemoral joint. Greater cartilage degradation on the medial half of the femoral head supports an association between increased trabecular alignment and cartilage degradation.  相似文献   

7.
Effect of diet on longitudinal bone growth and osteochondrosis in swine   总被引：1，自引：0，他引：1  
Weanling gilts were fed either a 12% or 16% protein diet for 10 weeks. Animals fed the 12% protein diet had reduced body weights and reduced longitudinal bone growth as measured in the distal radial growth plate. There was no difference in the growth plate widths between the two animal groups, but there was a significant reduction in the daily rate of cell production in the proliferative zone of animals fed the 12% protein diet. No effect of diet on the rate of expansion of the epiphysis at the articular-epiphyseal junction of the distal femur or humerus could be detected. All animals in both groups had morphologic cartilage lesions consistent with early changes associated with osteochondrosis (OCD), and there was no difference in the lesion morphology between the dietary groups. Areas of disorderly endochondral ossification in the radial growth plate were associated with perpendicular growth cartilage infractions. Growth plate lesions were characterized by increased widths of the maturing cartilage zone without increased width of the proliferative zone or an increase in the daily rate of cell production. Focal growth plate lesions developed because of a transitory inhibition of cartilage mineralization and resorption. Disorderly foci of endochondral ossification beneath articular cartilage were characterized by an area of chondrocyte necrosis which prevented normal cartilage matrix mineralization. Lamellae of cartilage necrosis were also present within the reserve zone of the articular cartilage. These were associated with abnormalities of the cartilage canal vessels, and chondrocyte necrosis was considered to precede degenerative changes in articular cartilage matrix.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
The objectives of this study were to investigate the activity of the matrix metalloproteinase (MMP)‐2 and MMP‐9 in healthy and in degenerative cartilage and to characterize the relation with the acute phase protein haptoglobin (HP) in articular cartilages of pigs. Joint surfaces of the proximal and distal humerus and femur of fattening pigs were histopathologically classified. In addition, cartilage homogenates and synovia were obtained. The tissue homogenates were analysed for gelatinase activity by zymography and by activity assay. The concentrations of HP in cartilage homogenates, in synovia and in serum were analysed by ELISA. High enzymatic activity of the MMP‐2 latent form was observed in zymography in all samples. Zymographic activities of MMP‐2 active form and MMP‐9 (active and latent form) were detected at low levels in some samples. Comparison of the zymographic activities of gelatinases in unaltered vs. altered cartilages yielded no differences. In contrast to zymography, cartilage homogenates were negative for MMP‐2 and MMP‐9 in the activity assays. The concentrations of HP in cartilage homogenates and in synovia from samples without alteration and from samples with massive alterations were not different. When classified according to their HP concentration, cartilage homogenates with increased HP concentrations had higher (p < 0.05) zymographic activities of the MMP‐2 active form. For the two MMPs investigated, there was no detectable relationship with degenerative processes in the cartilage.  相似文献   

9.
Osteoarthritis of the metacarpophalangeal joint is common cause of lameness in equine athletes, and is hallmarked by articular cartilage damage. An accurate, noninvasive method for measuring cartilage thickness would be beneficial to screen for cartilage injury and allow for prompt initiation of interventional therapy. The objective of this methods comparison study was to compare computed tomographic arthrography (CTA), magnetic resonance imaging (MRI), and magnetic resonance arthrography (MRA) measurements of articular cartilage thickness with gross measurements in the metacarpophalangeal joint of Thoroughbred horses. Fourteen cadaveric, equine thoracic limbs were included. Limbs were excluded from the study if pathology of the metacarpophalangeal articular cartilage was observed with any imaging modality. Articular cartilage thickness was measured in nine regions of the third metacarpal bone and proximal phalanx on sagittal plane MRI sequences. After intra‐articular contrast administration, the measurements were repeated on sagittal plane MRA and sagittal CTA reformations. In an effort to increase cartilage conspicuity, the volume of intra‐articular contrast was increased from 14.5 ml, to maximal distention for the second set of seven limbs. Mean and standard deviation values were calculated, and linear regression analysis was used to determine correlations between gross and imaging measurements of cartilage thickness. This study failed to identify one imaging test that consistently yielded measurements correlating with gross cartilage thickness. Even with the use of intra‐articular contrast, cartilage surfaces were difficult to differentiate in regions where the cartilage surfaces of the proximal phalanx and third metacarpal bone were in close contact with each other.  相似文献   

10.
The effects of systemically administered fibroblast growth factor-2 (FGF-2) at doses of 0.1 and 0.3 mg/kg/day for 7 days were investigated 5-week-old male SAMP6 mice, a model of low turnover osteopenia. The bone histomorphometry in the distal epiphyseal growth plate of the femur showed that 0.3 mg/kg/day of FGF-2 decreased the longitudinal growth rate and cartilage cell production rate and increased the growth plate width. Growth plate chondrocytes showed the features of defective endochondral ossification at the same dosage level. In the distal one third of the femur, the marrow trabecular area, endocortical mineral apposition rate and/or bone formation rate were increased in both the SAMP6 mice given 0.1 and 0.3 mg of FGF-2/kg/day. In this region, the endocortical osteoblasts were hypertrophied with some layers of overlying proliferated fibroblastic mesenchymal cells. The presence of small foci of bone formation within the layers of these mesenchymal cells indicates their osteogenic potential. On the other hand, the periosteal bone formation rate in the mid-shaft of the femur was depressed in the 0.3 mg/kg/day group. These results suggest that systemically administered FGF-2 may have the possibility to increase the peak bone mass in SAMP6 by stimulating the osteoprogenitor cells to proliferate and differentiate into osteoblasts and enhancing endocortical bone modelling. The higher dose of FGF-2, however, inhibited both endochondral and periosteal bone formation.  相似文献   

11.
The purpose of this study was to determine whether delayed gadolinium‐enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping are accurate techniques for measuring cartilage thickness in the metacarpus3/metatarsus3 (Mc3/Mt3) of Thoroughbred racehorses. Twenty‐four Mc3/Mt3 cadaver specimens were acquired from six healthy racehorses. Cartilage thickness was measured from postintra‐articular Gd‐DTPA2? images acquired using short tau inversion recovery (STIR), and proton density weighted (PDw) sequences, and compared with cartilage thickness measured from corresponding histologic images. Two observers performed each histologic measurement twice at three different sites, with measurement times spaced at least 5 days apart. Histologic cartilage thickness was measured at each of the three sites from the articular surface to the bone–cartilage interface, and from the articular surface to the mineralized cartilage interface (tidemark ) . Intra‐observer repeatability was good to moderate for dGEMRIC where Mc3/Mt3 cartilage was not in contact with the proximal phalanx. Where the Mc3/Mt3 cartilage was in contact with the proximal phalanx cartilage, dGEMRIC STIR and T2 mapping PDw cartilage thicknesses of Mc3/Mt3 could not be measured reliably. When measured from the articular surface to the bone–cartilage interface, histologic cartilage thickness did not differ from STIR or PDw cartilage thickness at the site where the Mc3/Mt3 cartilage surface was separated from the proximal phalanx cartilage (P > 0.05). Findings indicated that dGEMRIC STIR and T2 mapping PDw are accurate techniques for measuring Mc3/Mt3 cartilage thickness at locations where the cartilage is not in direct contact with the proximal phalanx cartilage.  相似文献   

12.
Recent evidence clearly indicates that basic fibroblast growth factor (bFGF) signal transduction is essential for normal skeletal development. Here, we report that bFGF and its receptor are specifically localized in the terminal hypertrophic chondrocytes of the porcine epiphyseal growth plate, the tissue responsible for longitudinal bone growth. Similar observations were obtained with the chondrocytes immediately adjacent to resorbing blood vessels in the secondary center of ossification of the epiphysis. These results are consistent with a recent proposal that bFGF functions in coupling osteogenesis with chondrogenesis by attracting the vascular invasion of cartilage from adjacent trabecular bone.  相似文献   

13.
This study was concerned with the dynamics of fatty acids in tissues involved in the growth and mineralization of the femur of Starbro chicks from 1 to 50 days of age. Four chickens that died of suffocation were obtained each day. Altogether, 400 femoral bones were studied in five age groups (I–V). Compact bone, spongy bone and articular cartilage were sampled. Lipids were extracted according to Folch and fatty acids were separated using gas chromatography. The fatty acid profile was found to change with age. Fatty acids with the highest content in bone were C18:1, C16:0, C18:2 and C18:0. The highest content of fatty acids was found in spongy bone and the lowest in articular cartilage. Several correlations were revealed between individual fatty acids. The following conclusions were drawn. (1) Fatty acid profiles in compact bone, spongy bone and articular cartilage change with age of chicks. (2) Oleic (C18:1), palmitic (C16:0), linoleic (C18:2), stearic (C18:0) and arachidonic (C20:4) acids accounted for most of the fatty acid pool. (3) Correlations in the content of fatty acids were noted between bone structures.  相似文献   

14.
The purpose of this study was to determine if variation in the ultrasound beam angle would affect cartilage thickness measurement performed with B-mode ultrasonography. Transverse sections of six fresh equine middle phalanges were obtained from necropsy. Ultrasonographic images of the proximal articular cartilage were obtained in a water bath, in a plane parallel and adjacent to the section plane using a 5-10 MHz linear transducer. Static images were acquired for all six bone specimens with an ultrasound beam angle of 0 degree, 30 degrees, 45 degrees, and 60 degrees. Proximal articular cartilage thickness was measured on ultrasonographic images and on the bone specimen at the same level. A linear mixed-effects model was used to compare articular cartilage thickness measured on specimen and on ultrasonographic images using different ultrasound beam angle. Mean +/- SD cartilage thickness was 1.82 +/- 0.35 mm on bone specimens, 1.72 +/- 0.29 with a 0 degrees angle, 1.99 +/- 0.34 with 30 degrees, 2.06 +/- 0.34 with 45 degrees, and 2.3 +/- 0.38 with 60 degrees. There was a significant difference between macroscopic measurements and ultrasonographic measurements performed with ultrasound angles at 30 degrees, 45 degrees, and 60 degrees. There was a significant increase in cartilage thickness when the ultrasound beam angle decreased (P = 0.0157; R2 = 0.969). Cartilage thickeness measured on ultrasonographic images varies with the ultrasound beam angle and may not be accurate because ultrasound speed in cartilage may be different than the speed used by the ultrasonographic unit for distance calculation.  相似文献   

15.
The thickness of the physeal cartilage (growth plate) was measured and the rate of longitudinal bone growth estimated in the femur, tibiotarsus and tarsometatarsus of different groups of domestic fowl. Birds were either a laying strain or broiler strain fed ad libitum, or a broiler strain on restricted feed. They were killed at different ages from hatching to 10 weeks and the mean thickness of the physeal cartilage and the mean estimated rate of longitudinal bone growth was calculated in the proximal bone extremities. Mean physeal thickness varied from 0.185 to 0.825 mm and longitudinal growth rates between 1.85 and 8.4 mm per week. When growth rates were plotted against physeal thickness the resulting scatter diagram suggested a positive linear relationship between the two. This study provides a range of baseline values for the assessment of proximal physeal thickness in other groups of fowl.  相似文献   

16.
Although there are many studies in the equine literature focused on articular diseases and the aetiology of osteoarthritis, few have concentrated on normal articular structures and how they change with age. The objective of this investigation was to study the thickness and morphology of the calcified cartilage layer of the distal metacarpus over a range of ages. A parasagittal slab of bone was sectioned from the region of sesamoid contact on the medial condyle of the metacarpi from 34 horses. The slab of bone was preserved, dehydrated and embedded, undecalcified, in methylmethacrylate and then stained with toluidine blue. Six repeatable fields of interest from the distal aspect of each metacarpus were digitised and examined to determine the morphology of the calcified cartilage layer. The thickness of the calcified cartilage, range 88-426 microm, was estimated using a method of integration. The results indicate an age-related influence on the thickness of the calcified cartilage layer, generally increased in older horses. While this finding is significant, perhaps more importantly a positional relationship was also identified, indicating that pressures endured by different regions within a joint may dictate morphological development of the tissues. This study has begun to lay the groundwork to determine whether the calcified layer of the hyaline cartilage could be involved in the development of osteoarthritis.  相似文献   

17.
应用茜素红—阿利新蓝双重染色技术制作骨与软骨透明标本,观察幼龄小鼠软骨发育的形态学变化。取1、3、5、7、9、15日龄完整幼鼠,水淹致死后去除皮肤、眼、脑、内脏和脂肪组织,乙醇固定,丙酮脱脂,自来水冲洗,茜素红—阿利新蓝混合染色,氢氧化钾透明,各梯度甘油脱水,纯甘油保存。结果小鼠骨骼双重染色硬骨显示为红色,软骨显示为蓝色。随着小鼠日龄的增长,小鼠肋软骨的骨化最为明显,后肢长骨末端的骺软骨板和髋部软骨骨化过程清晰可见。此试验可以清晰的显示不同日龄小鼠肋软骨、后肢关节软骨、髋部软骨的骨化过程。  相似文献   

18.
Samples of distal lateral radial growth plate cartilage were serially harvested from weanling Thoroughbreds after 0,3,6 and 9 months on diets providing either 100% or 130% of energy and protein requirements. The higher plane of nutrition was associated with decreased cartilage hexosamine and hydroxyproline contents and increased DNA contents. Similar observations followed the postmortem harvesting of humeral and radial articular cartilages after 9 months. These findings are consistent with previous reports suggesting that high-energy diets induce osteochondrotic changes in the cartilage of weanling horses.  相似文献   

19.
While articular cartilage changes are considered to be one of the initial events in the pathological cascade leading to osteoarthritis, these changes remain difficult to detect using conventional diagnostic imaging modalities such as plain radiography. The aim of this prospective, experimental, methods comparison study was to compare the sensitivity of magnetic resonance imaging (MRI), magnetic resonance arthrography, computed tomography (CT), and CT arthrography in the detection of artificially induced articular cartilage defects in the equine carpal joints. Defects were created in the antebrachiocarpal and middle carpal joint using curettage by a board‐certified equine surgeon. Normal articular cartilage thickness varied from a maximum of 1.22 mm at the level of the distal aspect of the radius to a minimum of 0.17 mm in the proximal articular surface of the third carpal bone. Regarding cartilaginous defect measurements the remaining cartilaginous bed range from a maximum of 0.776 mm in the partial thickness defects, and 0 mm (defect reaches the subchondral bone) when total thickness defect were made. Computed tomography and magnetic resonance imaging were performed followed by CT arthrography and magnetic resonance arthrography after antebrachiocarpal and middle carpal intraarticular contrast administration. All images were reviewed by two board‐certified veterinary radiologists, both of whom were blinded to the location, presence of, and thickness of the cartilage defects. A total number of 72 lesions in nine limbs were created. Mean sensitivity for localizing cartilage defects varied between imaging modalities with CT arthrography showing the best sensitivity (69.9%), followed by magnetic resonance arthrography (53.5%), MRI (33.3%), and CT (18.1%) respectively. The addition of contrast arthrography in both magnetic resonance and CT improved the rate of cartilage lesion detection although no statistical significance was found. Computed tomographic arthrography displayed the best sensitivity for detecting articular cartilage defects in the equine antebrachiocarpal and middle‐carpal joints, compared to magnetic resonance arthrography, MRI, and CT.  相似文献   

20.
A 2‐day‐old Warmblood filly was presented for examination of an angular limb deformity of the left front limb and an upright conformation of both metacarpophalangeal joints. Radiological examination revealed bilateral absence of the metacarpophalangeal joint space with fusion of the third metacarpal bone and first phalanx (synostosis). No treatment was undertaken. The filly was readmitted to the clinic 10 weeks later for bilateral front limb lameness. On radiological examination, the synostosis of the front metacarpophalangeal joints was still present. Physitis of the distal growth plate of the right third metacarpal bone and proximal growth plate of the right proximal phalanx, and an avulsion fracture of the palmaromedial and proximal aspect of the left middle phalanx, with a cystic like lesion on the medial aspect of distal first phalanx and proximal middle phalanx were diagnosed. Given the poor prognosis, the foal was subjected to euthanasia. Post mortem examination confirmed the absence of the metacarpophalangeal joint space with a trabecular bony union between the third metacarpal bone and the first phalanx. A rudimentary joint capsule was present at the level of the absent joints as well as a small zone of articular cartilage, which invaginated over a short distance into the dorsal trabecular bone on the right front limb. On the medial aspect of the left proximal interphalangeal joint, a focal defect of articular cartilage with exposure of subchondral bone was observed. This is the first case report of a foal born with congenital aplasia of both metacarpophalangeal joints. Congenital malformations should be considered as differential diagnosis in lame foals or foals born with angular or flexural limb deformities.  相似文献   

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