An osteodystrophy apparently caused by vitamin D deficiency in growing pigs

An osteodystrophy with features of both rickets and fibrous osteodystrophy was diagnosed in growing pigs housed indoors and fed on a diet deficient in vitamin D. Affected pigs were severely lame and preferred to remain recumbent. At necropsy, the long bones had reduced breaking strength and in one five-month-old pig the articular surfaces of both proximal humeri were indented due to collapse of subchondral bone. Microscopic changes in the bones included prominent osteoclastic activity in the proximal metaphyses, variable myelofibrosis, trabecular microfractures, and focal thickening of the hypertrophic zone in some growth plates. Treatment consisted of an injection of Vitamin D3, addition of dicalcium phosphate to the diet for 18 days and long-term supplementation of the diet with fat-soluble vitamins. This is the first report of an osteodystrophic disease in pigs in New Zealand.     

An osteodystrophy apparently caused by vitamin D deficiency in growing pigs

An osteodystrophy with features of both rickets and fibrous osteodystrophy was diagnosed in growing pigs housed indoors and fed on a diet deficient in vitamin D. Affected pigs were severely lame and preferred to remain recumbent. At necropsy, the long bones had reduced breaking strength and in one tive-month- old pig the articular surfaces of both proximal humeri were indented due to collapse of subchondral bone.

Microscopic changes in the bones included prominent osteoclastic activity in the proximal metaphyses, variable myelofibrosis, trabecular microfractures, and focal thickening of the hypertrophic zone in some growth plates.

Treatment consisted of an injection of Vitamin D₃, addition of dicalcium phosphate to the diet for 18 days and long-term supplementation of the diet with fat-soluble vitamins. This is the first report of an osteodystrophic disease in pigs in New Zealand.     

Skeletal lesions of canine hepatozoonosis caused by Hepatozoon americanum

Canine hepatozoonosis, caused by Hepatozoon americanum, is an emerging tick-borne disease of dogs in North America. In addition to the skeletal and cardiac myositis that are prominent features of the disease, there is disseminated periosteal bone proliferation in most dogs that manifest clinical disease. Each of six experimentally infected animals (four dogs and two coyotes) and seven of eight naturally infected dogs had gross or histopathologic osteoproliferative lesions. Experimental animals were 6-9 months of age when exposed. Naturally infected dogs were 8 months to 11 years old when subjected to necropsy. Lesions occurred primarily on the diaphysis of the more proximal long bones of the limbs; however, flat and irregular bones were frequently involved. Lesions involving metacarpals, metatarsals, and digits were infrequent. The earliest observed periosteal lesions were in an experimentally infected dog 32 days after exposure to sporulated oocysts of H. americanum. There were hypertrophy and hyperplasia of osteoprogenitor cells, and osteoblasts appeared in the cellular zone of the periosteum. Spicules of woven bone oriented perpendicularly to bone cortex followed. Later yet, periosteal new bone was remodeled and tended to become oriented parallel to the cortical bone. Horizontally oriented zones of remodeled, condensed bone sometimes occurred in multiple layers on the original cortex, forming "pseudocortices." The osseous lesions of American canine hepatozoonosis, with few variations, are remarkably similar to those of hypertrophic osteopathy in domestic dogs and other mammalian species, including humans.     

Patterns of cell proliferation and growth rate in limb bones of the domestic fowl (Gallus domesticus)

The growth rates of each extremity of the tibiotarsus (TibT) and tarsometatarsus (TMT) bones and of a phalangeal bone were measured in Rhode Island red chicks. Histological sections of the growth plates at each of these sites were made for measurements of the thickness of the flattened dividing cell layer and counts of the number of cells between its boundaries. The diameter of the mature chondrocytes in the metaphysis was also measured. The extent of the dividing cell population within the flattened cell layer and the proportion of cells in division were measured from autoradiographs prepared after labelling dividing cells in vitro or in vivo (three birds in each group) with tritiated thymidine. From the results the rate of cell production in the plane of growth at each growth plate was estimated. It varied from about six cells per day at each end of the phalanx to just over 50 cells per day at the proximal end of the TibT and TMT. The duration of the cycle time was estimated to be 13 to 21 hours at the proximal TibT and TMT and distal TibT but considerably longer at the distal TMT and at both ends of the phalanx. Variation in growth rate between extremities of the bones examined was associated largely with variation in the dividing cell populations and the thickness of the flattened cell layer, but it appears that there were also significant differences in cell cycle times between sites. The in vitro and in vivo labelling techniques gave comparable results.     

Rickets in yearling steers wintered on a swede (Brassica napus) crop

Rickets was diagnosed in a group of 80 yearling Angus steers wintered for three months on a crop of swedes (Brassica napus) in the Kimbolton area. Growth rate was poor and several steers developed lameness during the final three weeks on the crop. Five animals were euthanased after developing bone fractures. Necropsy of two animals revealed soft ribs, enlarged costochondral junctions and irregularly thickened growth plates in long bones. Histologically there were islands of hypertrophic cartilage within metaphyses and disruption of metaphyseal trabeculae. Thickened, irregular, trabeculae were sometimes lined by wide osteoid seams. Phosphorus deficiency was considered to be the most likely aetiology of the osteodystrophy. The dry matter content of the swedes was only six percent, and in order to satisfy their phosphorus requirements each steer would have had to ingest approximately 330 kg of swedes per day. Rickets is an uncommon disease of grazing animals in New Zealand and to our knowledge this is the first report of its occurrence in cattle.     

Postnatal limb bone growth in relation to live weight in pigs from birth to 84 days of age.

Long limb bones were dissected from 30 Camborough x Canabrid pigs serially slaughtered at birth, 14, 28, 56, and 84 d of age to determine the growth patterns of long limb bones (humerus and radius for the forelimb and femur and tibia for the hindlimb) in relation to live weight from birth to 84 d of age, weighing up to approximately 31 kg. Relationships between individual long limb bone measurements (Y) and live weight or transformations of live weight (X) were evaluated using allometric analyses. Hindlimb bones tended to have higher growth coefficients than forelimb bones (P < .05), suggesting an anterior-posterior gradient of long limb bone growth. However, centripetal gradients of growth for long limb bones were not evidential (P > .05). Greater diameter growth compared with length growth of the long limb bones indicated that the differentiation in growth for diameter and length of the long limb bones was an effective response to the functional requirements of standing, walking, and running following birth.     

Growth and shape modelling of the rabbit tibia: study of the dynamics of developing skeleton

The proliferative impulse of the growth plate cartilage and related structures and its effect on the dimensions of long bones are well documented. The modulation of shape, however, is less known, and in general, it is referred to the coupled resorption/apposition process of bone modelling. A morphometric study was carried out on rabbit tibiae comparing size increments and shape changes in relation to age. Utilizing measurements made using dried bones, radiography and computerized tomography, it was possible to perform a three-dimensional analysis of shape modulation occurring during a period of growth extending from 3 months to 1 year of age. The dynamics of the shape changes related to growth were studied with a fluorescent tetracycline labelling. This enabled correlation of shape modulation with the 3-D distribution of apposition and resorption. The current thinking behind the influences and mechanical forces affecting bone architecture was discussed in the light of these findings. Several factors play a role in the structural organization of the human and upper vertebrates' skeleton, whose shape is genetically determined in the complex process usually referred as 'modelling'. This does not conflict with the existing evidence of remodelling being influenced by mechanical stimuli, but the unsolved question remains how physical forces (strains) act on the biological substrate of cartilage and bone cells.     

Congenital spinal stenosis in beef calves in western Canada

Nineteen calves with a clinical history of posterior weakness or ataxia were examined at necropsy. Dorsoventral narrowing of the vertebral canal and myelopathy were found in the thoracic and lumbar areas of the spinal cord; vertebral metaphyseal growth plates had focal areas of premature closure. Malformation of the cranial base and hydrocephalus were also observed. Shortening of long bones and malformation of long bone epiphyses were prominent findings and were associated with focal premature closure of metaphyseal growth plates. The cause of these lesions is unknown; possible causes, including a maternal deficiency of manganese, are discussed.     

Some observations on the development of the long bones of ratite birds

Observations were made on the long bones of 16 young ratite birds (10 rheas, 3 emus and 3 ostriches), from 1-day-old to 12 weeks of age.
At hatching all long bones contained large cartilaginous cones which were continuous with the growth plates, and an osseous cortex. At one week of age ossification had commenced on the periphery of these embryonic cones and in some bones the cones had become separated from the growth plates. At 3 weeks of age the embryonic cones of cartilage were still present in the proximal and distal tibio-tarsi and narrow cartilaginous bridges connected the cones to the growth plates. Embryonic cones were not present in other long bones of this 3-week-old rhea nor in the long bones of ratites 6, 8 and 12 weeks of age. Other praecocial birds such as turkey poults and chickens have cones of embryonic cartilage in their long bones at hatching and these persist in the tibio-tarsi till one to 2 weeks of age. The presence of large cones of embryonic cartilage in the tibio-tarsal bones of 3-week-old ratite birds is probably a normal phenomenon. Awareness of this feature is necessary for the correct differential diagnosis of the prevalent musculoskeletal disorders of ratite birds.     

Treatment of fractured antebrachial bones in both thoracic extremities in toy breed dogs by application of reconstruction plates

Stabilization of fractures at distal third of antebrachial bones in toy breed dogs is often connected with bone healing complications, including delayed union or non-union. In the present study 9 toy breed dogs with fractures at distal third of the epiphysis of two antebrachial bones were treated. Each dog had fractured both thoracic limbs. In all the dogs, internal stabilization was applied using the 1 mm, 4 or 5 -hole reconstructive mini plates. In three dogs mini plates were applied in treatment of non-union of antebrachial bones. In each case radius bone was stabilized only. X-ray examination performed in all the dogs 10 weeks postoperatively showed complete adhesion of treated bones. It was found that application of reconstructive mini plates in treatment of simultaneous fractures of distal shaft of both antebrachial bones is effective therapeutic method.     

Effect of plane of nutrition and age on carcass maturity of sheep

One hundred twenty ewe and wether lambs were fed high (76% TDN, 12.3% crude protein) or low (70.6% TDN, 16.1% crude protein) energy diets and slaughtered at average ages of 261, 356 or 469 d. High planes of nutrition for lambs at 356 or 469 d of age resulted in heavier carcasses, thicker fat depth and higher flank streaking scores compared to lambs fed low planes of nutrition. Rib bone, break joint and overall maturity scores were not influenced (P greater than .05) by diet. Metacarpal and metatarsal bones from lambs fed high planes of nutrition were slightly longer and heavier and required more force to break (P less than .05) compared with bones from lambs fed low planes of nutrition. The majority of the ewes fed high or low planes of nutrition had fused growth plates and possessed spool joints by 469 d; none of the wethers had spool joints. An additional 27 wethers were slaughtered at an average of 480, 578 or 662 d. Rib bone, break joint and overall maturity scores were not different (P greater than .05) for animals fed the high or low energy diets, but bone weight and shaft break force values were higher for those fed high energy diets. At 662 d of age, only 20% of the wethers on each dietary regimen possessed fused growth plates. Overall, plane of nutrition in market-weight lambs and yearlings had very little influence on the presence or absence of a break joint or on other bone maturity scores.(ABSTRACT TRUNCATED AT 250 WORDS)     

Relationship of high intensity step-up lighting to bone ash and growth plate closure of the tarso-metatarsus in turkeys

The reduced lameness observed in turkeys reared in a high intensity step-up (HISU) lighting programme as compared to a low intensity step-down (LISD) lighting regimen cannot be explained by differences in the inorganic matrix of the bone, because the proportions of bone ash, bone ash calcium, and bone ash phosphorus did not differ between lighting programmes. At 17 weeks of age, there was a significant difference in the proportion of closed growth plates in males reared on the HISU programme rather than on LISD lighting. These results support the hypothesis that HISU lighting reduces lameness by promoting earlier growth plate closure of long bones.     

Histopathologic study of long-bone growth plates confirms the basset hound as an osteochondrodysplastic breed

Osteochondrodysplasias are caused by abnormal development and growth of cartilage and bone. These abnormalities have been reported in both humans and animals with dwarfism. The basset hound is considered a breed with a disproportionate prevalence of dwarfism, the cause of which is unknown. To determine the type of osteochondrodysplasia in this breed, we analyzed histologically the growth plates from the long bones of a basset hound and a Doberman pinscher, both 2 mo old. Tissue was fixed in 4% paraformaldehyde, embedded in paraffin, sectioned at 5 microm, stained with hematoxylin and eosin, and analyzed by light microscopy. Our results suggest that by this method the basset hound can be defined only as a breed having osteochondrodysplasia due to a primary cartilage problem in the growth plate.     

Characteristics of Metacarpal Bones from Cows of Different Ages and Weights

Metacarpals from 59 Angus/Gelbvieh rotationally crossed cows were studied to determine whether bone loss occurs in beef cows between 33 and 153 mo of age. Bone loss or a change in bone composition could affect lean meat yield and proportions of carcass components such as ash. With the exception of 18 single-calf cows that were fed a high concentrate diet after their calves were weaned at 120 d of age, all cows with suckling calves grazed the same pastures. Calves from pasture-fed cows were weaned 46 d before the cows were slaughtered on October 23. Although carcasses from 153-mo-old, pasture-fed cows were heavier (P<0.01) than those from 33-mo-old, pasture-fed cows, no differences (P>0.05) in metacarpal weight, length, cortex shaft area, moisture in cortex, or ash in cortex were observed. Weight and length of metacarpals from 33-mo-old pasture-fed cows with 226.8-kg carcasses were similar (P>0.05) to those from 33-mo-old concentrate-fed cows with 409.3-kg carcasses. Metacarpals from the concentrate-fed, single-calf cows were then compared with those from 129-mo-old cows. Again, no differences (P>0.05) in weight or length of the bones were present. Low correlation coefficients obtained by pooling data for all 59 cows confirmed that no differences (P>0.05) in weight or length of bones existed among animals varying greatly in weight or age. Because complete calcification of the epiphyseal growth plates on the metacarpals occurs prior to 33 mo of age, no change in length was expected. However, our findings that no change in metacarpal weight or bone cortex composition occurred with large changes in age or weight are of interest. Within Angus/Gelbvieh crossed cows, the lean:bone ratio is based entirely on changes in muscle mass because bone mass remains constant. In addition to muscle mass, changes in fat content influence bone percentage in the carcass.     

肉鸡胫骨软骨发育不良早期钙黏蛋白1(CDH1)差异表达研究

为研究福美双诱发肉鸡胫骨软骨发育不良(Tibial Dyschondroplasia,TD)早期钙黏蛋白1(CDH1)的差异表达,基础日粮中添加福美双,在试验第1、2、6天,对试验鸡进行剖杀,迅速采取胫骨生长板故入4％多聚甲醛溶液于4℃固定,做CDH1免疫组化分析;提取对照组和饲喂福美双组的生长板总RNA,采用Real-time PCR对CDH1 基因进行差异表达验证.结果钙黏蛋白1 (CDH1/E-cadherin)基因在TD生长板表达上调,在对照和TD软骨生长板,其蛋白合成主要在前肥大、肥大区软骨细胞质,增殖区软骨细胞无表达,钙化区软骨细胞表达少,在饲喂福美双第1、2、6天其表达增加与定量PCR变化结果相一致,且在饲喂福美双第2、6天呈明显高表达.结果表明CDH1 参与细胞黏附、血管入侵及调节Wnt/β-cat的信号传递,和其它分子共同调节软骨内骨化.     

北极狐骨骼的比较解剖研究

对北极狐骨骼系统进行解训观察,同时与革食动物马、牛及杂食动物猪的骨骼作形态学上的比较。由于生活习性所致,北极狐骨骼形态结构具有如下特征:北极狐的骨骼由头骨、躯干骨和四肢骨组成。头骨的主要特征是:枕骨的颈交不发达,眶上突不与颧弓相连,无眶上孔;颞骨岩部形成半球形鼓泡,鼻骨与颌前骨的鼻突之间不形成鼻颌切迹;泪骨几乎无颜面部;颌前骨的鼻突发达;上颌骨外面无面嵴;腭骨发达;犁骨腹缘后部不与鼻腔底壁接触;下颌骨支下缘无血管切迹、垂直部后下方有一角突。四肢骨的主要特征是:肩胛岗下端形成肩峰;臂骨未见三角肌结节和圆肌结节;尺骨比桡骨细长;腕骨7块;掌骨5块;指骨5指;左右髋骨几乎平行排列,坐骨弓宽平,荐结节高出荐骨;股骨有发达的大转子和较发达的小转子,缺第三转子;腓骨与胫骨等长;跗骨7块;躯干骨由7个颈椎、13个胸椎、7个腰椎、3个荐椎、15—17个尾椎组成;肋骨13对;胸骨由8个长柱状的胸骨节片和剑状软骨构成。     

Morphological changes of the cartilage and bone in newborn piglets evoked by experimentally induced glucocorticoid excess during pregnancy

The study examined articular and growth plate cartilages as well as bone tissues in the offspring of sows treated with glucocorticoid during the last 45 days of pregnancy (dexamethasone at the dose of 0.03 mg/kg body weight intramuscularly, every second day). The offspring were tested at the birth and basal morphology for both articular and growth plate cartilages, and the histomorphometry of trabeculae of the epiphysis and metaphysis of femur and tibia were established. The concentration of selected cytokines and the activity of bone alkaline phosphatase were determined in blood serum. Maternal dexamethasone (DEX) administration reduced the thickness of proliferative, resting and hypertrophic zones of growth plate of femur and tibia of male piglets when compared with the control. DEX significantly reduced the thickness of the resting zone in both bones. It also elongated proliferative and hypertrophic zones of the growth plate in the femur as well as the hypertrophic zone in the tibia of female piglets when compared with the control group. Moreover, DEX decreased the articular cartilage thickness of the tibia in female piglets and enhanced the articular cartilage thickness of the femur in male piglets. Articular cartilage was highly cellular, and chondrocytes were separated by thin septa of matrix. An analysis of the trabecular bone architecture in male piglets showed a loss of the trabecular bone by thinning and DEX‐related increase in trabecular porosity. Moreover, the cortical bone looked similar to the trabeculae because of trabecularization of the cortex. There was a DEX that reduced serum osteocalcin and BAP concentrations in both female and male newborn piglets, whereas the serum IL‐1 and Il‐6 was reduced only in male piglets. The obtained results demonstrated that DEX administration to sows during the last 45 days of pregnancy might cause the growth to slow and eventually to stop, especially in male piglets. It might lead to an alteration within the cartilage during its normal function, and with the time, arthritic changes can follow.     

Morphology of the inferior pharyngeal bones of white bream (Blicca bjoerkna) in River Warta

The inferior pharyngeal bones are a characteristic feature of the Cyprinidae. Morphology of inferior pharyngeal bones is important in the diagnosis of carnivorous food, or determining the diet of fishes. Due to the lack of literature data, the aim of the study was to examine the morphology of the inferior pharyngeal bone in detail. 102 Blicca bjoerkna specimens caught in the River Warta (Poland) were analysed. 204 inferior pharyngeal bones were collected. The parameters of the inferior pharyngeal bones correlated with the measured head features and the total fish length. The arches of inferior pharyngeal bones did not have directional asymmetry for the two main parameters (height and width of inferior pharyngeal bone). However, there was a left‐sided directional asymmetry of the ventral part of inferior pharyngeal bone. In the case of the B. bjoerkna from River Warta, large differences in terms of individual parameters of inferior pharyngeal bones were observed. Fluctuation asymmetry was low. Shape of inferior pharyngeal bones was very round. In total, 12 teeth formulas were described. The 35.29% of the fish had formula different than described in the literature 2.5–5.2 and more teeth in the right arches. Following identification, measurements of the structures enable estimation of the lengths and weights of prey to be determined from biometric relationships. Analysis of body morphological features in combination with pharyngeal bone morphology could show a hybrid in the Warta river's population.     

Matrix metalloproteinase expression and localization in turkey (Meleagris gallopavo) during the endochondral ossification process

Vertebrate long bones are formed by endochondral ossification, a process accompanied by changes in extracellular matrix synthesis and remodeling, performed mainly by the matrix metalloproteinases (MMP). The temporal/spatial expression patterns of 5 members of the MMP family known to be important for endochondral ossification were studied, for the first time, in the turkey growth plate during embryonic and juvenile stages. The expression of MMP-2 was detected in the proliferative zone, MMP-3, MMP-9, and MMP-13 in cells lining the blood vessels; MMP-13 was also detected in hypertrophic chondrocytes. The MMP-16 expression was detected in the reserve zone of the growth plate. These results present a detailed survey of turkey MMP, serving as a data source (atlas) for further studies in this subject.     

THE ACCURACY OF THE DORSOPROXIMAL-DORSODISTAL PROJECTION IN ASSESSING THIRD CARPAL BONE SCLEROSIS IN STANDARDBRED TROTTERS

Thirty-five carpal joints from 20 standardbred trotters, age 1 to 7 years, all euthanized for nonorthopedic reasons, were examined to investigate the correlation between assessments of subchondral bone sclerosis in the third carpal bone from radiographs in the dorsoproximal-dorsodistal (DPr-DDi) projection and histomorphometric bone volume density measurements. The agreement between assessments of sclerosis from antemortem versus postmortem radiographs was also evaluated. Bones graded as sclerotic in the DPr-DDi projection had significantly higher bone volume density values for all areas of measurement than nonsclerotic bones. For sclerotic bones, grading of sclerosis was significantly associated with volume density measurements in the central cancellous bone only. There was a good agreement ( k _w =0.71) between assessments of radiographic bone sclerosis from antemortem versus postmortem radiographs.