Search

We captured a <1-d-old male elk calf (Cervus canadensis) with a shortened neck. Postmortem examination revealed trauma, meconium aspiration syndrome, and cervical vertebral malformation (partial fusion and narrowed disc spaces). This observation is novel in a wild elk calf, although the gross lesions resembled complex vertebral malformation in neonatal cattle., (© Wildlife Disease Association 2023.)

Vertebral deformities in salmonid interspecific hybrids, some of which were triploidised, were assessed across three separate year classes during the freshwater life stage. Initially, eggs from a farmed Atlantic salmon Salmo salar were crossed with the sperm from a S. salar, arctic char Salvelinus alpinus or brown trout Salmo trutta. For S. salar × S. trutta, half the eggs were triploidised. In a second- and third-year class, the eggs from a farmed S. salar were crossed with the sperm from either a S. salar or a S. trutta, and half of each group was triploidised. In the two initial-year classes, all hybrids were larger than the S. salar controls, and triploid S. salar × S. trutta were larger than diploid counterparts. In the third-year class, the S. salar × S. trutta were smaller than the S. salar, in contrast to the initial 2 year classes, although the triploid hybrids were still larger than the diploids. In the third-year class, a high degree of spontaneous triploidy was also observed in the putative diploid groups (between 16 and 39%). Vertebral deformities were consistently higher in pressure-shocked triploids than diploids, irrespective of hybridisation, but there was no consistent effect of hybridisation among experiments. Although this study was not able to explain the contrasting results for vertebral deformities between year classes, triploid S. salar × S. trutta can demonstrate impressive freshwater growth that could be of interest for future farming programmes., (© 2020 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.)

As a first attempt to assess bone health in cleaner fish production, wild and cultured ballan wrasse Labrus bergylta and lumpfish Cyclopterus lumpus were examined by radiology. In C. lumpus, wild fish (57%) had more vertebra deformities (≥1 deformed vertebrae) than cultured fish (2-16%). One wild C. lumpus had lordosis and another was missing the tail fin. In L. bergylta, wild fish (11%) had fewer vertebra deformities than cultured individuals (78-91%). Among the cultured L. bergylta, 17-53% of the fish had severe vertebra deformities (≥6 deformed vertebrae) with two predominate sites of location, one between vertebra 4 and 10 (S1) in the trunk, and one between 19 and 26 (S2) in the tail. Fusions dominated S1, while compressions dominated S2. Although wild L. bergylta had a low vertebra deformity level, 83% had calluses and 14% had fractures in haemal/neural spines and/or ribs. The site-specific appearance and pathology of fracture and callus in wild L. bergylta suggests these are induced by chronic mechanical stress, and a possible pathogenesis for fish hyperostosis is presented based on this notion. In conclusion, good bone health was documented in cultured C. lumpus, but cultured L. bergylta suffered poor bone health. How this affects survival, growth, swimming abilities and welfare in cultured wrasse should be further investigated. SIGNIFICANCE STATEMENT: Skeletal deformities were studied in ballan wrasse and lumpfish of both wild and cultured origin for the first time to identify potential welfare issues when deploying them as cleaner fish in salmon sea cages. While cultured lumpfish showed good bone health, cultured wrasse had a high occurrence of vertebra deformities, which is expected to impact lice eating efficiency and animal welfare negatively. These deformities are most likely induced early in development., (© 2020 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.)

A 6-y-old female dromedary camel ( Camelus dromedarius L.) was presented for assessment of firm, bilateral swellings rostral and ventral to the eyes. Serum biochemistry revealed hyperglycemia (28.5 mmol/L), hypocalcemia (1.27 mmol/L), hyperphosphatemia (3.39 mmol/L), hypoproteinemia (total protein 50 g/L), and hypoalbuminemia (20 g/L). Based on the poor prognosis associated with the presumptive diagnosis of fibrous osteodystrophy, the camel was euthanized. Gross postmortem findings revealed expanded fibrous tissue replacing the maxilla and mandible, and bilaterally prominent parathyroid glands. Histology of the maxilla revealed proliferative loose fibrous tissue with widely scattered, regularly spaced, small spicules of mineralized bone. The parathyroid glands were prominent bilaterally; the internal and external parathyroid glands were composed of plump cells with abundant pale basophilic cytoplasm and open nuclei. The pathologic findings were consistent with the antemortem diagnosis of fibrous osteodystrophy. The camel's diet, which was not specifically balanced for a camel, included grass hay, sweet feed, and alfalfa pellets. The camel's caregivers reported feeding her treats of cookies. A feed analysis was not available. The biochemistry abnormalities and clinical and postmortem findings, along with a diet that was not balanced for a camel, are consistent with a diagnosis of nutritional secondary hyperparathyroidism.

Osteofibrous dysplasia is a rare and benign nonneoplastic condition of unknown etiology in humans and mammals. An adult female cockatiel ( Nymphicus hollandicus ) was presented with the following problems: a soft tissue mass on the left frontal area of the head that extended over the left eye, anorexia, lethargy, and emaciation. Computed tomographic imaging and ultrasonography revealed a soft tissue opacity in the left cranial area of the head with multifocal heterogeneous opacities and foci of mineralization. Cytological, histopathological, and immunohistochemistry examinations were performed on biopsy samples from tissue collected from the mass. Following surgical removal of the cranial mass the patient was treated with a nonsteroidal anti-inflammatory drug and antibiotic medication. The surgical site healed with no complications and through follow-up examinations there were no signs of reoccurrence of the abnormal tissue for 2 months. Through cytological and histopathological examination and immunohistochemistry testing of the submitted tissue, a diagnosis of osteofibrous dysplasia was determined.

The Creeper (Cp) chicken is characterized by chondrodystrophy in Cp/+ heterozygotes and embryonic lethality in Cp/Cp homozygotes. However, the genes underlying the phenotypes have not been fully known. Here, we show that a 25 kb deletion on chromosome 7, which contains the Indian hedgehog (IHH) and non-homologous end-joining factor 1 (NHEJ1) genes, is responsible for the Cp trait in Japanese bantam chickens. IHH is essential for chondrocyte maturation and is downregulated in the Cp/+ embryos and completely lost in the Cp/Cp embryos. This indicates that chondrodystrophy is caused by the loss of IHH and that chondrocyte maturation is delayed in Cp/+ heterozygotes. The Cp/Cp homozygotes exhibit impaired DNA double-strand break (DSB) repair due to the loss of NHEJ1, resulting in DSB accumulation in the vascular and nervous systems, which leads to apoptosis and early embryonic death.

Thoracolumbar intervertebral disk herniation (TL-IVDH) with caudal articular process anomalies has been reported in Pugs. It currently remains unclear whether congenital caudal articular process aplasia/hypoplasia predisposes to the development of TL-IVDH. However, there are difficulties in proving the causal relationship between caudal articular process anomalies and TL-IVDH. The aim of this study was to describe the prevalence of TL-IVDH at the vertebral space containing anomalous and normal caudal articular processes in Pugs. Fifty-seven pugs were eligible to be included in this study. Caudal articular process aplasia/hypoplasia affected 52/57 (91.2%) dogs. The caudal articular process anomalies were most frequently located between T10 and T13. Colocalization of caudal articular process aplasia/hypoplasia and TL-IVDH was detected in 11 dogs (19.3%). The prevalence of TL-IVDH at vertebral spaces containing abnormal caudal articular processes was 12.3%, whereas the prevalence of TL-IVDH at vertebral spaces containing normal articular processes was 2.4%. With the increase in the number of vertebrae with caudal articular process anomalies, the prevalence of TL-IVDH also increased. The results of this study suggested the prevalence of caudal articular process anomalies was high in Pugs. The caudal articular process anomalies could be associated with TL-IVDH. A large cohort is needed to prove the causal relationship between caudal articular process anomalies and TL-IVDH.

Background: A retrospective case series study was undertaken to describe the magnetic resonance imaging (MRI) findings in Pug dogs with thoracolumbar myelopathy and concurrent caudal articular process (CAP) dysplasia. Electronic clinical records were searched for Pug dogs who underwent MRI for the investigation of a T3-L3 spinal cord segment disease with subsequent confirmation of CAP dysplasia with computed tomography between January 2013 and June 2017. Clinical parameters age, gender, neuter status, body weight, urinary or faecal incontinence, severity and duration of clinical signs were recorded. MRI abnormalities were described. Univariable non-parametric tests investigated the association between the clinical parameters and evidence of extra- or intra-dural spinal cord compression on MRI., Results: 18 Pug dogs were included. The median age was 106 months with median duration of clinical signs 5 months. All presented with variable severity of spastic paraparesis and ataxia; 50% suffered urinary/faecal incontinence. In all cases, MRI revealed a focal increase in T2-weighted signal intensity within the spinal cord at an intervertebral level where bilateral CAP dysplasia was present; this was bilateral aplasia in all but one case, which had one aplastic and one severely hypoplastic CAP. MRI lesions were associated with spinal cord compression in all but one case; intervertebral disc protrusion resulted in extra-dural compression in 10 (56%) cases; intra-dural compression was associated with a suspected arachnoid diverticulum in 4 (22%) cases and suspected pia-arachnoid fibrosis in 3 cases (17%). There was no association between clinical parameters and a diagnosis of intra-dural vs extra-dural compression. CAP dysplasia occurred at multiple levels in the T10-13 region with bilateral aplasia at T11-12 most often associated with corresponding spinal cord lesions on MRI., Conclusions: All Pugs dogs in this study were presented for chronic progressive ambulatory paraparesis; incontinence was commonly reported. Although intervertebral disc disease was the most common radiologic diagnosis, intra-dural compression associated with arachnoid diverticulae/fibrosis was also common. Bilateral CAP aplasia was present in all but one Pug dog at the level of MRI detectable spinal cord lesions. A causal relationship between CAP dysplasia and causes of thoracolumbar myelopathy is speculated but is not confirmed by this study.

The aims of this study were to evaluate the prevalence and anatomical characteristics of thoracic caudal articular process dysplasia in French bulldogs, English bulldogs and Pugs presenting for problems unrelated to spinal disease. In this retrospective cross-sectional study, computed tomography scans of the thoracic vertebral column of these three breeds were reviewed for the presence and location of caudal articular process hypoplasia and aplasia, and compared between breeds. A total of 271 dogs met the inclusion criteria: 108 French bulldogs, 63 English bulldogs, and 100 Pugs. A total of 70.4% of French bulldogs, 84.1% of English bulldogs, and 97.0% of Pugs showed evidence of caudal articular process dysplasia. Compared to French and English bulldogs, Pugs showed a significantly higher prevalence of caudal articular process aplasia, but also a lower prevalence of caudal articular process hypoplasia, a higher number of affected vertebrae per dog and demonstrated a generalized and bilateral spatial pattern more frequently. Furthermore, Pugs showed a significantly different anatomical distribution of caudal articular process dysplasia along the vertebral column, with a high prevalence of caudal articular process aplasia between T10 and T13. This area was almost completely spared in French and English bulldogs. As previously suggested, caudal articular process dysplasia is a common finding in neurologically normal Pugs but this also seems to apply to French and English bulldogs. The predisposition of clinically relevant caudal articular process dysplasia in Pugs is possibly not only caused by the higher prevalence of caudal articular process dysplasia, but also by breed specific anatomical characteristics., (© 2018 American College of Veterinary Radiology.)

Impairment of bone growth at a young age leads to dwarfism in adulthood. Dwarfism can be categorised as either proportionate, an overall size reduction without changes in body proportions, or disproportionate, a size reduction in one or more limbs, with changes in body proportions. Many forms of dwarfism are inherited and result from structural disruptions or disrupted signalling pathways. Hormonal disruptions are evident in Brooksville miniature Brahman cattle and Z-linked dwarfism in chickens, caused by mutations in GH1 and GHR. Furthermore, mutations in IHH are the underlying cause of creeper achondroplasia in chickens. Belgian blue cattle display proportionate dwarfism caused by a mutation in RNF11, while American Angus cattle dwarfism is caused by a mutation in PRKG2. Mutations in EVC2 are associated with dwarfism in Japanese brown cattle and Tyrolean grey cattle. Fleckvieh dwarfism is caused by mutations in the GON4L gene. Mutations in COL10A1 and COL2A1 cause dwarfism in pigs and Holstein cattle, both associated with structural disruptions, while several mutations in ACAN are associated with bulldog-type dwarfism in Dexter cattle and dwarfism in American miniature horses. In other equine breeds, such as Shetland ponies and Friesian horses, dwarfism is caused by mutations in SHOX and B4GALT7. In Texel sheep, chondrodysplasia is associated with a deletion in SLC13A1. This review discusses genes known to be involved in these and other forms of dwarfism in livestock., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objectives: To determine the risk of condylar fracture, or of needing to have a transcondylar screw placed, and to identify risk factors in a cohort of dogs with humeral intracondylar fissure (also known as incomplete ossification of the humeral condyle) that was initially managed non-surgically., Methods: A retrospective owner survey of dogs diagnosed with humeral intracondylar fissure as an incidental finding and managed non-surgically with a minimum of two years follow-up. Body weight, age, estimated fissure size, gender and contralateral fracture at the time of diagnosis were evaluated as potential risk factors for the development of a humeral condylar fracture or for having a transcondylar screw placed., Results: Data were available for 30 dogs (34 elbows). Six humeral condyles with a mean fissure size of 50% fractured at a mean of 14 months after diagnosis. A transcondylar screw was placed across two humeral condyles with fissure sizes of 60 and 100% at 11 and 17 months. No risk factors were identified for fracture/screw placement. For those cases that did not fracture or have a screw placed mean fissure size was 52% and mean follow-up time was 56 months (range 29 to 79 months)., Clinical Significance: Eighteen percent of cases progressed to fracture and 24% in total required surgery. This information allows clinicians and owners to make an informed decision regarding surgery when faced with a dog with humeral intracondylar fissure identified as an incidental finding., (© 2017 British Small Animal Veterinary Association.)

Reared Senegalese sole Solea senegalensis Kaup show a high incidence of vertebral anomalies; however, little is known about its skeletal anomaly profile in the later farming phases. The purpose of this study was to provide a detailed description and quantification of the most common skeletal anomalies in reared Senegalese sole in the juvenile stage by means of computed radiography. A total of 374 Senegalese sole were classified according to the external morphology of the fish as normal or altered and then radiographed in latero-lateral and in dorso-ventral projections. Radiographic evaluation of anomalies focused especially on vertebral body anomalies (VBA) and vertebral column deviations (VCD). The 2 orthogonal projections provided a more complete visualization of the skeleton. Approximately 75% of the individuals showed at least 1 anomaly, while VBA and/or VCD were detected in 48.9% of the specimens. Regarding external morphology, 88% of the fish were categorized as normal, although about 72% of these normal fish displayed abnormalities in radiographies. The most frequent anomalies consisted of deformations of the caudal complex plates (hypurals, parhypural and epural), preurals and caudal vertebrae. Scoliosis was the most prevalent among VCD, affecting the caudal area in almost 15% of the individuals. The anomaly profile at the juvenile stages showed some differences compared to what has been reported previously in earlier stages of development. In light of these results, further investigation into the progression of skeletal anomalies over time and the causative factors at later stages is required.

Metaphyseal osteopathy (MO) (hypertrophic osteodystrophy) is a developmental disorder of unexplained etiology affecting dogs during rapid growth. Affected dogs experience relapsing episodes of lytic/sclerotic metaphyseal lesions and systemic inflammation. MO is rare in the general dog population; however, some breeds (Weimaraner, Great Dane and Irish Setter) have a much higher incidence, supporting a hereditary etiology. Autoinflammatory childhood disorders of parallel presentation such as chronic recurrent multifocal osteomyelitis (CRMO), and deficiency of interleukin-1 receptor antagonist (DIRA), involve impaired innate immunity pathways and aberrant cytokine production. Given the similarities between these diseases, we hypothesize that MO is an autoinflammatory disease mediated by cytokines involved in innate immunity. To characterize immune dysregulation in MO dogs we measured serum levels of inflammatory markers in 26 MO and 102 control dogs. MO dogs had significantly higher levels (pg/ml) of serum Interleukin-1beta (IL-1β), IL-18, IL-6, Granulocyte-macrophage colony stimulating factor (GM-CSF), C-X-C motif chemokine 10 (CXCL10), tumor necrosis factor (TNF), and IL-10. Notably, recovered MO dogs were not different from dogs during active MO disease, providing a suggestive mechanism for disease predisposition. This is the first documentation of elevated immune markers in MO dogs, uncovering an immune profile similar to comparable autoinflammatory disorders in children., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: To use micro-computed tomography (CT) to evaluate the fissure-fracture pattern in dogs affected by medial coronoid disease (MCD)., Study Design: Prospective case-controlled study., Sample Population: Client owned (n = 21) and cadaver dogs (n = 5)., Methods: Segments were excised by subtotal coronoid ostectomy from dogs with MCD. Two categories were identified: fissured (Fi) or fractured (F). Three subcategories were contingent on fissure-fracture orientation: tip (T), radial incisure (RI), and radial incisure encroaching tip (RIT). Control segments were from nondiseased cadavers. High-resolution micro-CT (3 dimensional and 2 dimensional) was performed on all segments. Measurements included mean bone mineral density, trabecular number and thickness, and the angle of the fissure-fracture relative to the predominant trabecular orientation., Results: A total of 28 diseased segments from 21 dogs (mean age 23.3 months, mean bodyweight 31.5 kg) were analyzed and categorized according to fissure-fragment location as Fi-T (n = 2), Fi-RIT (n = 2), Fi-RI (n = 3), F-T (n = 5), F-RIT (n = 9), F-RI (n = 7). The 3D analysis revealed subchondral micro-fracturing occurred in association with fragmentation. Canalicular impaction was associated with increase in trabecular number and decrease in trabecular space, most notably in RI categories. The 2D analysis showed that predominant trabecular orientation in control segments was significantly different to RI but not to T. The mean (SD) angle difference between the orientation of fissure-fracture and the predominant trabecular pattern was 6.9 (6.9)° for RI and 44.6 (49.6) ° for T., Conclusion: T and RI fissure-fracture patterns show morphologic differences and likely arise from different supraphysiologic loading. Medial compartment disease is not homogenous and pattern recognition may assist further investigation of etiopathogenesis., (© Copyright 2016 by The American College of Veterinary Surgeons.)

Recessive skeletal dysplasia, characterized by joint- and/or hip bone-enlargement, was mapped within the critical region for a major quantitative trait locus (QTL) influencing carcass weight; previously named CW-3 in Japanese Black cattle. The risk allele was on the same chromosome as the Q allele that increases carcass weight. Phenotypic characterization revealed that the risk allele causes disproportional tall stature and bone size that increases carcass weight in heterozygous individuals but causes disproportionately narrow chest width in homozygotes. A non-synonymous variant of FGD3 was identified as a positional candidate quantitative trait nucleotide (QTN) and the corresponding mutant protein showed reduced activity as a guanine nucleotide exchange factor for Cdc42. FGD3 is expressed in the growth plate cartilage of femurs from bovine and mouse. Thus, loss of FDG3 activity may lead to subsequent loss of Cdc42 function. This would be consistent with the columnar disorganization of proliferating chondrocytes in chondrocyte-specific inactivated Cdc42 mutant mice. This is the first report showing association of FGD3 with skeletal dysplasia.

Objectives: To assess intrathecal pressure (ITP) in chondrodystrophic dogs with thoracolumbar disk extrusion., Study Design: Prospective cohort study., Animals: Group 1: 11 chondrodystrophic dogs with thoracolumbar disk extrusion and present deep pain sensation. Group 2 (control): 3 healthy chondrodystrophic laboratory dogs without spinal disease., Methods: Diagnosis was based on neurologic signs, magnetic resonance imaging (MRI) findings, and surgical confirmation. Blood pressure was maintained within physiologic range during anesthesia. A standardized surgical procedure was applied to minimize factors that could influence measurement readings. An extended hemilaminectomy was performed and ITP was measured with a fiber optic catheter. The catheter was inserted in the subarachnoid space 1 spinal segment caudal to the level of herniation and its tip was advanced to the site of compression., Results: Significantly higher ITP occurred in chondrodystrophic dogs with acute thoracolumbar disk disease compared with controls. ITP was not associated with duration of clinical signs, neurologic status, outcome, degree of spinal cord compression, or signal intensity changes as assessed by MRI., Conclusion: Acute thoracolumbar disk disease leads to elevated ITP in chondrodystrophic dogs, which may contribute to increased compression of spinal cord parenchyma., (© Copyright 2015 by The American College of Veterinary Surgeons.)

Objectives: To evaluate the effect of periosteal transection and elevation in foals with naturally occurring carpal valgus deviation., Study Design: Prospective clinical study., Animals: Foals (n = 9) with bilateral carpal valgus., Methods: Foals with bilateral carpal valgus had distolateral radial periosteal transection and elevation (PE) including distal ulnar transection on 1 limb. Foals were stall confined until the skin incisions healed, and then allowed free exercise in a small paddock or round pen. Dorsopalmar carpal radiographs were obtained at 14 day intervals to determine the carpal valgus angle (CVA) until it was <5°., Results: All limbs had a reduction in CVA and there was no significant difference in total carpal valgus angular correction or the rate at which the correction occurred between the surgical and control limb., Conclusions: Unilateral distolateral radial PE had no effect on carpal angulation in 9 foals with naturally occurring bilateral carpal valgus deviation when performed between 19 and 43 days., (© Copyright 2015 by The American College of Veterinary Surgeons.)

Metaphyseal osteopathy, otherwise known as hypertrophic osteodystrophy, is a disease that causes pyrexia and lethargy accompanied by pain in the thoracic and pelvic limbs of rapidly growing large-breed dogs. While metaphyseal osteopathy has been descibed in association with slipped capital femoral epiphysis in cats, it has not previously been reported as a cause of limb pain and pyrexia in this species. A 7-month-old British Shorthair cat presented with a 1 month history of pyrexia, lethargy and pain in all limbs. Investigation included radiographs of the limbs and chest, abdominal ultrasound, serum biochemical analysis, haematology, bone biopsy, joint fluid aspiration and cytology. Findings were consistent with a diagnosis of metaphyseal osteopathy. The cat's clinical signs resolved following the administration of prednisolone. Symptoms recurred 1 month after the cessation of prednisolone therapy, but resolved when administration was resumed., (© ISFM and AAFP 2014.)

Objective: To (1) evaluate thoracic limb loads and symmetry, and elbow function and morphology, before and after arthroscopic treatment of unilateral medial coronoid process disease (MCPD), and (2) determine if functional variables correlate with morphologic findings., Study Design: Prospective case series., Animals: Dogs (n = 14) with thoracic limb lameness., Methods: Dogs were included when unilateral MCPD was confirmed as the cause of lameness. Kinetic analysis of both thoracic limbs, along with kinematic analysis and goniometry of both elbows were carried out before, and 60, 120, and 180 days after partial coronoidectomy by arthroscopy. Radiography and computed tomography of both elbows were performed before and 180 days after arthroscopy., Results: A nonsignificant (P = .11) increase in the peak vertical loads (PFz), and a significant (P = .022) increase in the vertical impulse (iFz) applied by the affected limb were seen. Symmetry indices improved, with significant differences between sessions (PFz: P = .019; iFz: P = .003). Kinematic variables showed no significant differences, between sessions or when comparing both elbows within sessions. Goniometry revealed no significant differences between sessions, but some significant differences were identified when comparing both elbows within sessions. Osteophytosis and degree of lameness showed no correlation, before (rs  = -0.077; P = .79) or after arthroscopy (rs  = 0.27; P = .35)., Conclusions: Kinetic variables improved after arthroscopy, without full restoration of function. Kinematic variables did not change significantly. Osteoarthritis and goniometric measurements in the affected joint worsened. Functional variables did not correlate with morphologic findings., (© Copyright 2014 by The American College of Veterinary Surgeons.)

Case Report: Metaphyseal osteopathy (MO) was diagnosed in three Australian Kelpie puppies that were presented for veterinary assessment of lameness. The three puppies were siblings. Each was from a different litter by the same breeding pair. The puppy in case one was seen by the authors, and the puppies in cases two and three were patients at other veterinary hospitals. However, the medical records and radiographs were examined and reviewed for this report. Radiographic investigation of the lameness revealed pathognomonic appearance of MO affecting the metaphyseal region of the long bones in all three puppies. The diagnosis was confirmed on histopathology in one patient., Conclusion: MO is considered a disease of large and giant-breed dogs, being rarely reported in non-large-breed dogs, and has not been reported in the Australian Kelpie, which is considered a medium-breed dog. This case series suggests a previously unreported breed predisposition to MO in the Australian Kelpie., (© 2014 Australian Veterinary Association.)

This paper reports a newly described form of skeletal dysplasia affecting Brazilian hair sheep of the Cabugi breed. This breed is characterized by having a short head and in some cases the animals are smaller and more compact than sheep of similar breeds. Lambs born with craniofacial abnormalities and dwarfism that die at 2-6 months of age are frequent in this breed. In a flock of 68 ewes and three rams of the Cabugi breed, 134 lambs were born over a 4-year period. Of these, 14 (10.4%) had marked cranial abnormalities and dwarfism and died or were humanely destroyed, 43 (32%) had a normal face and 77 (57.5%) had the short face characteristic of the breed. Dwarf lambs were much smaller than normal, with short legs, a domed head with retruded muzzle and protruded mandible, sternal deformities and exophthalmic eyes situated more laterally in the face than normal. Microscopical examination of long bones of the limbs, bones of the base of the skull and vertebrae showed no lesions. Bones from four affected lambs and one control lamb were macerated for morphometric examination. Although the length of the spinal cord was similar, there was disproportionate shortening of the appendicular bones, particularly the distal segments. Thus the disease was defined as a skeletal dysplasia characterized by craniofacial deformity and disproportionate dwarfism. It is suggested that the disease is inherited as an incomplete dominant trait. The shortened face, which is a feature of the Cabugi breed, may represent the heterozygous state and the more severe, often lethal, dwarfism may occur in homozygotes., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Reasons for Performing the Study: Few reports are available on the relationship between developmental orthopaedic diseases (DOD) and future performances in Warmblood horses., Objectives: To investigate the relationship between performance and the presence of DOD lesions., Methods: Records of Warmblood stallions for which radiographic and performance data were available were collected. Showjumping performances were expressed as scores derived from the final ranking of horses in each competition. These scores are available in an established performance database. The relationship between radiographic findings and both performance scores and number of performances was analysed using a linear regression model., Results: Two hundred and fifteen horses met the inclusion criteria. There was no difference in either the number of performances or performance score between horses categorised as affected with DOD lesions (independent of joint location) compared with controls. Significantly lower numbers of performances were recorded for horses with osteochondral fragments (OCD) located at the dorsal aspect of the sagittal ridge of the metacarpo/metatarsophalangeal bone. No significant difference was found between horses affected with DOD lesions of the tarsocrural joint and controls. Horses with osteochondrosis of the lateral trochlear ridge of the femur had both significantly lower performance scores and numbers of performances compared with controls., Conclusion: This study demonstrated that specific DOD location and site within the joint have an influence on performance. Osteochondral fragments in the femoropatellar and at the dorsal aspect of the sagittal ridge of the metacarpo/metatarsophalangeal joint resulted in lowered performance. Fragmentation in the tarsocrural joint had no influence on performance., Potential Relevance: The future athletic performance of Warmblood jumping horses may be limited as a result of OCD in the femoropatellar joint and to a certain extent the metacarpo/metatarsophalangeal joint., (© 2012 EVJ Ltd.)

The possible aetiology of osteochondrosis and, to a lesser extent, other developmental orthopaedic diseases or juvenile osteochondral conditions (JOCC), has been intensively investigated. However, most studies have focused on single factors of this multi-factorial disorder, or have been conducted under experimental conditions. This paper aims to present and discuss the scientific background of the BOSAC (Breeding, Osteochondral Status and Athletic Career) research program, a multi-factorial investigation on JOCC risk factors in field conditions. The epidemiology of JOCC in horses born in Normandy between 2002 and 2004 was studied. Horses were subjected to repeated body measurements, blood sampling and locomotion evaluation from birth until yearling sales. A radiographic examination, including 10 views of the limbs, was performed on each subject at approximately 6 and 17months of age. Information on nutrition and management programmes was collected by specialists from visits to the farms and the use of questionnaires. A total of 393 foals of three French breeds were monitored from birth to weaning, and 321 of these remained available for further follow-up, making the study unique as regards both the number of subjects and the variety of information collected. The study was designed to describe the evolution of JOCC, and determine possible early markers, risk factors and prognostic factors with respect to performance. Relevant data, suitable for epidemiological analyses, were collected under various field conditions that reflect current management practices in Normandy, France's main horse breeding region., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Elbow dysplasia is a common debilitating condition of large and giant breed dogs. Environmental factors and a complex genetic heritability play a role in predisposing dogs to elbow dysplasia with two aetiopathogeneses suggested for the development of the disease. Osteochondrosis was initially thought to cause elbow dysplasia, but more recent evidence has strongly supported various forms of joint incongruity as the most likely cause in most cases. Radioulnar length discrepancies and humeroulnar curvature mismatch have been implicated as the cause of medial coronoid disease and ununited anconeal process, but radial incisure incongruity and biceps/brachialis muscle forces could possibly play a role in some dogs. Treatment of elbow dysplasia should address articular pathology, such as fragmented coronoid process, osteochondrosis, cartilage damage and ununited anconeal process as well as any identified underlying causes. Finally, several palliative procedures have been developed to address more advanced elbow disease and might offer improved outcomes compared to conventional medical management., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objective: To report thoracolumbar caudal articular process malformations with secondary constrictive fibrosis of the spinal cord in Pugs., Design: Retrospective case series., Animals: 11 Pugs with neurologic dysfunction resulting from constriction of fibrous tissue secondary to thoracolumbar caudal articular process malformation and 5 Pugs with no neurologic dysfunction., Procedures: Medical records of dogs with myelopathy presumably caused by constriction of fibrous tissue secondary to thoracolumbar caudal articular process malformation at 2 referral institutions between 1993 and 2009 were reviewed. Dogs were included in the study if hypoplastic or aplastic thoracolumbar caudal articular processes were present on radiographs, CT images, or MRI images., Results: The most common neurologic examination findings were paraparesis with ataxia or paraplegia but no evidence of hyperpathia along the vertebral column. All dogs' neurologic lesion localization was to the T3-L3 spinal cord segments. Median age at examination was 7. 7 years (range, 2 to 11 years). Five of 11 dogs had a history of unrelated trauma. Four of 11 dogs had urinary or fecal incontinence. Eight of 11 dogs underwent surgical exploration. Despite surgical intervention, all dogs that survived surgery continued to have neurologic deficits., Conclusions and Clinical Relevance: In the present study, presence of aplastic or hypoplastic articular processes in the thoracolumbar region did not always produce neurologic signs. However, fibrous constrictive myelopathy should be considered in Pugs with pelvic limb gait and postural reaction deficits and lack of hyperpathia upon palpation of the vertebral column. Additional studies are warranted to further characterize the disease process and determine the most effective means of treatment.

Incomplete ossification of the humeral condyle (IOHC) is characterized by an intracondylar fissure located where the intercondylar physis is present in growing dogs. Its radiologic and computed tomographic features have been described but the magnetic resonance (MR) features have not been characterized. Our purpose was to further describe the range of MRappearances of IOHC, to assess the diagnostic capability of MRrelative to radiology, and to determine whether MRis able to identify the disease before a fissure forms. Thirty-eight elbow MRscans and radiographs, when available, were reviewed and divided into three groups. In Group 1 (affected elbows, n = 22), there was an intracondylar defect on MRwith variable appearance; the defect was not visible radiographically in 32% of the elbows. The main difference between Group 2 (nonaffected elbows, n = 6) and Group 3 (contralaterals to IOHC or to condylar fracture, without fissure, n = 10) was the appearance of the humeral condyle in short tau inversion recovery (STIR) sequences: all elbows in Group 2 had a homogeneous humeral condyle, whereas all but one in Group 3 were heterogeneous. One dog in Group 3 developed a complete condylar fissure 7 months after the first examination, when no evidence of an intracondylar defect had been detected. The MRappearance of IOHC is variable and a heterogeneous humeral condyle in STIR images without a clear defect may warn of the possibility for the subsequent development of a condylar fissure., (© 2012 Veterinary Radiology & Ultrasound.)

Congenital chondrodystrophy of unknown origin (CCUO), often referred to as 'acorn calf disease' or congenital joint laxity and dwarfism (CJLD), has been reported in beef cattle in Canada, the United States, Europe, South Africa, New Zealand and Australia. An association of CCUO with grazing drought-affected pastures, feeding hay-only or silage-only diets or supplementation with apple pulp suggests a nutritional cause such as a mineral deficiency. This review compares published reports on CCUO in order to identify common features among outbreaks and to provide a basis for future research into the condition. A protocol for investigation of outbreaks is provided to improve the outcome of future comparisons., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Hinged circular external skeletal fixator constructs are used to perform sequential correction of angular limb deformities, often with resultant limb segment lengthening, via distraction osteogenesis. Although there are several reports describing the use of these constructs for correction of antebrachial deformities in dogs, there is little information regarding their use on other limb segments. This report describes the use of hinged circular fixator constructs for the correction of acquired crural deformities in three skeletally immature dogs., Case Reports: Two dogs had purely frontal plane deformities (one valgus, one varus) and the third dog had frontal (valgus) and sagittal (recurvatum) components to its deformity. At the time of long-term evaluation, frontal plane angulation relative to the contralateral limb improved from 40° to 22° of valgus, 30° to 5° of valgus, and 20° to 1° of varus in the three individual dogs. Tibial length discrepancies of 12% and 22% that were initially present in two dogs were improved to 6% and 10%, respectively, of the contralateral tibial length at the time of final evaluation; both dogs had compensatory growth of the ipsilateral femur and all dogs had an excellent functional outcome., Conclusion: These cases illustrate the value of using hinged circular fixator constructs for correction of crural angular deformities, particularly when length discrepancies of the tibia are present., (© 2012 The Authors. Australian Veterinary Journal © 2012 Australian Veterinary Association.)

Objective: To report the computed tomographic (CT) documentation of humeral intracondylar fissure (HIF) developing after complete ossification of the humeral condyle (HC)., Study Design: Clinical report., Animals: Male 3 year old working (English) Cocker Spaniel., Methods: Sequential CT screening (659-day interval between analyses)., Results: A sagittal hypodense fissure typical of incomplete ossification of the humeral condyle (IOHC) was identified ≈ 22 months after screening CT examination documented a normal elbow joint., Conclusion: Even in dogs with clinical features typical of the condition most commonly termed IOHC, fissure formation and propagation can occur after ossification is complete., (© Copyright 2011 by The American College of Veterinary Surgeons.)

Rabbits obtained from a South African rabbit breeder exhibited deformities of the distal forelimbs. The clinical, radiological and histological presentation of mid-antebrachial valgus formation (a.k.a distal foreleg curvature) in these rabbits was consistent with an autosomal recessive trait associated with a chondrodystrophic lesion of the distal ulna epiphysis 1st described in the 1960s. The impact this might have on South African farming enterprises and laboratory facilities has not been established, but the heritability and welfare implications of this condition make it a concern. Mildly affected animals can adapt to the deformity with some housing adjustments, but severely affected animals may require humane euthanasia.

Objective: To describe incidence and type of postoperative complications in the surgical management of incomplete ossification of the humeral condyle (IOHC) and identify any risk factors associated with development of these complications., Study Design: Case series., Methods: Clinical records of dogs (n=57) that had prophylactic transcondylar screw insertion for treatment of IOHC (79 elbows) at 6 UK referral centers were reviewed. Signalment, presentation, surgical management, postoperative care, and complications were recorded. Postoperative complications were divided into seroma, surgical site infections (SSI) and implant complications., Results: Spaniel breeds and entire males were overrepresented. The overall complication rate was 59.5%. Seroma (n=25) and SSI (24) were the most commonly encountered complications. Implant failure occurred in 2 dogs. Labrador retrievers were at greater risk of developing a postoperative complication than other breeds (P=.03). Increasing bodyweight was a significant risk factor for development of a SSI (P=.03). Placement of the transcondylar screw in lag fashion rather than as a positional screw reduced the incidence of postoperative SSI (P=.007)., Conclusions: Surgical management of IOHC is associated with a high rate of postoperative complications. Placement of the transcondylar screw in lag fashion may limit postoperative complications and warrants further consideration., (© Copyright 2011 by The American College of Veterinary Surgeons.)

Developmental Orthopaedic Disease (DOD) in limb joints is frequent, can cause lameness and is a major cause of economic losses for the horse breeding industry. Studies on risk factors for DOD usually dichotomise the outcome to presence/absence without considering the extent of the disease, which can be appreciated by the number or the severity of the lesions. The aim of this study was to assess the effects of growth, exercise conditions and feeding practices on the number of radiographic findings (RF) of DOD in a cohort of horses, assuming that the risk factors associated with the presence of the disease and the number of RF may differ. We recruited broodmares on 21 stud farms in the Normandy region, France in 2002-2004. The stud farms were visited regularly to collect growth, exercise conditions, and feeding practices data from the end of the gestation to the weaning of the foal. The carpus, the front and hind digits, the tarsus and the stifle of the foals were radiographed at approximately six months of age. Each foal was classified according to the absence (no RF) or presence (≥1 RF) of DOD and to the number of RF. A zero-inflated Poisson model was used to simultaneously determine risk factors for presence/absence and for the number of RF of the disease. The convenience sample consisted of 378 foals, 53.1% of which did not have any RF. The mean number of RF per foal was 1.25 and the variance was 2.80. Comparing to the Poisson, negative binomial, and zero-inflated negative binomial regressions, the zero-inflated Poisson model was found to be best suited for these data. Of the 295 foals with complete data, three risk factors were significantly associated with a higher risk of being affected by DOD: high wither height increase, large group size in pasture and large pasture size. Seven risk factors were associated with the number of RF: wither height at 30 days of age, age of the mare, breed, regularity of exercise, Ca/P level in the mare and foal rations, group size in pasture, and the type and frequency of handling. This study shows that risk factors vary for the presence and extent of DOD, and that the use of a count model achieves a more detailed determination of risk factors for the presence of DOD and for the number of RF of DOD compared to the more conventional dichotomy presence/absence of the disease., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Results from radiographic screening for canine hip dysplasia (CHD) and elbow dysplasia (CED) of 48 367 German shepherd dogs born in 2001-07 were used for the population genetic analyses. Available information included CHD scores for 47 730 dogs, CED scores for 28 011 dogs and detailed veterinary diagnoses of primary ED lesions for a subsample of 18 899 dogs. Quasi-continuous traits were CHD, CED and cases of CED without radiographically visible primary lesion (CED-ARTH). Binary coding was used for fragmented medial coronoid process of the ulna (FCP), borderline findings and mild to severe signs of dysplasia in hip and elbow joints. Genetic parameters were estimated in univariate threshold and multivariate linear and mixed linear-threshold models using Gibbs sampling. Correlations between univariately predicted breeding values (BV) indicated genetic differences between borderline and affected disease status for both CHD (r(BV) = 0.5) and CED (r(BV) = 0.3). Multivariate genetic analyses with separate consideration of borderline findings revealed moderate heritabilities of 0.2-0.3 for the quasi-continuous traits with positive additive genetic correlation of 0.3 between CHD and both CED and CED-ARTH. For FCP, heritability of 0.6 and additive genetic correlations of +0.1 to CHD and -0.1 to CED-ARTH were estimated. Results supported the relevant genetic determination of CHD and CED, argued for both diseases against interpretation of borderline findings as healthy and implied genetic heterogeneity of CED. Accordingly, future breeding strategies to reduce the prevalences of CHD and CED in the German shepherd dog should be most efficient when based on BV from multivariate genetic evaluation for CHD, CED-ARTH and FCP with use of the whole scale of categories for classification of CHD and CED., (© 2011 Blackwell Verlag GmbH.)

A 10-week-old intact female Australian shepherd dog was presented sternally recumbent, mildly pyrexic, and painful on long bone palpation of both forelimbs. Based on radiographs she was diagnosed with hypertrophic osteodystrophy. Analgesia was provided with intravenous, oral, and topical medications. Approximately 2 wk later she was presented for facial swelling, regional dermatitis, and lymphadenopathy. Canine juvenile cellulitis was diagnosed and successfully treated.

This report describes a 4 mo old intact male Akita that presented for evaluation of a life-long history of facial swelling and failure to thrive. Physical examination revealed an enlarged cranium with prominent bony swellings on the maxillary bone, excessive laxity and crepitus involving multiple joints, and proprioceptive deficits. Radiographs demonstrated multiple osseous abnormalities including endosteal thickening of the femurs and ilium. Necropsy revealed gross compression of the cerebellum and brainstem. Physical exam findings, radiographic abnormalities, and histopathology of multiple bony lesions were all consistent with craniomandibular osteopathy. In this unique case of craniomandibular osteopathy, the dog was affected with severe bony proliferations leading to generalized hyperostotic lesions and brainstem compression resulting in neurologic deficits.

A hypoattenuating lesion in the left humeral condyle of an American cocker spaniel consistent with partial incomplete ossification of the humeral condyle was observed on computed tomography. Left forelimb lameness developed over the following three weeks at which time repeat computed tomography examination confirmed propagation of the lesion. Lameness resolved following placement of a transcondylar positional screw, suggesting that lameness was secondary to condylar instability. To the authors' knowledge this is the first report of propagation of an intracondylar lesion in a dog., (© 2010 British Small Animal Veterinary Association.)

Background: Canine hip dysplasia (HD) is a common polygenic trait characterized by hip malformation that results in osteoarthritis (OA). The condition in dogs is very similar to developmental dysplasia of the human hip which also leads to OA., Methodology/principal Findings: A total of 721 dogs, including both an association and linkage population, were genotyped. The association population included 8 pure breeds (Labrador retriever, Greyhounds, German Shepherd, Newfoundland, Golden retriever, Rottweiler, Border Collie and Bernese Mountain Dog). The linkage population included Labrador retrievers, Greyhounds, and their crosses. Of these, 366 dogs were genotyped at ∼22,000 single nucleotide polymorphism (SNP) loci and a targeted screen across 8 chromosomes with ∼3,300 SNPs was performed on 551 dogs (196 dogs were common to both sets). A mixed linear model approach was used to perform an association study on this combined association and linkage population. The study identified 4 susceptibility SNPs associated with HD and 2 SNPs associated with hip OA., Conclusion/significance: The identified SNPs included those near known genes (PTPRD, PARD3B, and COL15A1) reported to be associated with, or expressed in, OA in humans. This suggested that the canine model could provide a unique opportunity to identify genes underlying natural HD and hip OA, which are common and debilitating conditions in both dogs and humans.

A case-control study was conducted on 46 farms in south-eastern Australia with a recent history of congenital chondrodystrophy of unknown origin (CCUO) between 2002 and 2007. For each farm data was collected using face-to-face interviews concerning the management of case and control mobs during the gestation period in which affected calves were born. Data concerning the paddocks in which gestating cattle were maintained was also collected for analysis. Three separate multivariable models were constructed using generalised linear mixed models (GLMMs). The first model was based on the dichotomous outcome of mob status (affected/not affected) and included explanatory variables for management and environment factors. The second model used a novel approach, taking into account the number of cases in affected mobs in order to utilise available data. The outcome events/trials was used where the numerator was equal to the number of affected calves in a mob, and the denominator was equal to the total number of calves in the mob. The third model used the dichotomous outcome paddock status and included environmental and soil variables for paddocks involved with case and control mobs. Confounding for dam age and year affected was included in the mob outcome models, and random effects for paddock and farm were incorporated into the models. The birth of CCUO calves was associated with dams grazing native pastures on hilly terrain during gestation. Low levels of pasture were also associated with the outcome. The two models used for the mob outcome were similar in many respects. The events/trial model included the use of supplemental feed and an interaction term. This study demonstrates an association between a maternal nutritional disturbance and the occurrence of CCUO.

The coxofemoral joint is the most commonly luxated joint in dogs and cats. Coxofemoral luxations are generally craniodorsal; caudoventral coxofemoral luxations are relatively rare occurrences and may be accompanied by fracture of the greater trochanter. The aim of our study was to report the results of a modified Knowles toggle pin application in two caudoventral hip luxations for which closed reduction had not been achieved. Medical records of dogs and cats, which had been presented at our institution between September 1999 and October 2007, were reviewed for cases of coxofemoral luxation. In total, the case records of 67 cats and 147 dogs were found. Of these cases, there was one cat and one dog with caudoventral coxofemoral luxation. For both cases, the toggle pin technique was the method of treatment. The cat had a good clinical recovery within three days after surgery. The dog, which also had a cruciate ligament rupture in the same limb and medial patellar luxation in the contralateral limb, was presented with severe lameness and pain approximately two and a half months after surgery, at which time fracture of the femoral head was diagnosed. Functional recovery was achieved after a femoral head and neck ostectomy had been performed.

Arachnomelia syndrome is a lethal inherited malformation mainly of the limbs, vertebral column and skull in cattle, which poses a severe impairment to farmers and breeders. Recently, a number of cases of arachnomelia syndrome have occurred in the Simmental breed and some sires with excellent breeding values had been shown to be carriers of the disease. We herein report the genetic mapping of the mutation underlying arachnomelia in cattle. The disease was mapped using a two-stage genome scan. A first round autosomal genome-wide screening using a limited number of cases identified three chromosomal regions with lod-scores > 1. The position of the arachnomelia syndrome locus was identified to be on BTA 23 by genotyping an additional, independent set of animals with markers that provided positive lod-scores in the course of the initial genome-wide screen. Using a denser set of regional microsatellites, the locus could be mapped to a region about 9 cM in length. The most significant linkage signal with arachnomelia syndrome was obtained with marker NRKM-17 (lod-score > 20) using a recessive model. Interestingly, different genes seem to be responsible for the disease in Brown Swiss and Simmental breeds, as arachnomelia syndrome was mapped to a different location in Brown Swiss. The results provide sufficient information for the development of a genetic test system and also allow the identification of positional candidate genes.

A radiographic study documented shoulder dysplasia (n = 43), with varying degrees of malformation of the supraglenoid and infraglenoid tubercles and the coracoid process, shallowing or loss of the glenoid cavity, flattening or loss of the humeral head, malformation of the greater and lesser tubercles, loss of the intertubercle groove, and humeral diaphyseal abnormalities, in northern koalas (Phascolarctos cinereus) in the San Diego Zoo (San Diego, California, USA) colony. Retrospectively, historic radiographs (n = 38) were examined where available. Prospectively, three standard views (lateral extended arm, ventrodorsal cranially positioned arms, and ventrodorsal caudally positioned arms) were imaged (n = 25). In all radiographs, shoulders were graded as normal, or mildly, moderately, or severely dysplastic. Although affected koalas typically do not exhibit clinical signs, degenerative joint disease may develop and clinical signs treated with nonsteroidal anti-inflammatory drugs. Where shoulder and hip radiographs were both available (n = 60), 92% of individuals had correlation between the degree of shoulder and hip dysplasia.

The aim of this study was the analysis of non-genetic and genetic factors influencing elbow dysplasia (ED) in a Labrador retriever population. We analysed scores of elbow dysplasia from the official screening programme of the Labrador Club Deutschland (LCD) following the protocol of the International Elbow Working Group. The data set included X-rays from 2931 Labrador retrievers. These dogs were born between 2000 and 2004 and originated from 834 litters and 315 kennels. The pedigree file contained 27 305 dogs pertaining to 20 generations. We analysed four different traits including ED-Mit as the averaged result of ED scores from both elbow joints, ED-Max as the higher score of both elbow joints and ED-links and ED-rechts as the ED score of left or right elbow joint. Animal models were employed to estimate heritabilities, additive genetic correlation and residual correlation using residual maximum likelihood (REML). Significant effects for all four ED-traits were gender, month of birth and inbreeding coefficient. The fixed effect of birth year showed only significant effects for ED-Mit and ED-rechts. Age at examination was not significant. Heritability estimates for ED-Mit were 0.12 +/- 0.03, for ED-Max 0.11 +/- 0.03 and 0.13 +/- 0.03 for ED-links as well as 0.07 +/- 0.02 for ED-rechts. Heritability for female dogs was 0.12 +/- 0.03 and 0.10 +/- 0.03 for male dogs. The additive genetic correlation between ED-links and ED-rechts was 1 and the residual correlation 0.64. The heritabilities for ED were low to moderate based on models employed here and taking this into consideration, selection response will be small when employing phenotypic ED scores from breeding animals as the sole selection criterion. Therefore, breeding programmes should be supported by breeding values as tools for selection of breeding dogs. There was no difference in heritabilities between the mean ED score of the joints or the ED score of the joint with the higher ED grade. Furthermore, either specific genetic effects from a body side or sex-specific genetic effects could be observed for the expression of ED. Dogs showing radiographic signs of ED or dogs having been submitted for a surgery due to clinical signs of ED have to be precluded from breeding. The veterinary practitioner can help to reduce the frequency of dogs exhibiting a genetic disposition to ED when the radiographs of the elbow joints of many as possible purebred dogs are submitted to the respective dog breeding associations.

This article reviews nutritional and hormonal influences, diseases with uncertain etiology, and hereditary disorders affecting the growth and development of the long bones in dogs and cats.

Most llama and alpaca crias will be born without complication and survive the neonatal period without incident. However, it is important to be able to recognize which crias are likely to be at risk of complications so that you are best able to advise owners and take the correct course of action if required. This article deals with management of the pregnant camelid, the events associated with parturition and the peripartum period with emphasis on the cria, management of the newborn cria including assessment of passive transfer of immunity, issues relating to prematurity, and the major congenital defects that may present as emergencies within the neonatal period.

Leg disorders have become a major concern in comercial poutltry meat production. The mechanisms which cause leg problems are not completely understood. It has been hypothesed that high growth rate and low locomotor activity are the main factors. The particular effects of the different factors have been elucidated in special experiments. The locomotor activity of broilers with different growth rates has been observed in deep litter compartments with videotracking technique. The effects of locomotor activity were analysed through a training on treadmills in slow and fast growing broilers. Fast growing broilers showed a lower activity level from week one onwards and there was a pronounced drop in walking distances in the third week of age (21 to 8 meters per hour), while the slow growing broilers maintained a high activity level from 36 m throughout the fattening period. Systematic training of fast growing birds on treadmills increased the locomotion ability, the bone density and thickness and reduced the bending and twisting in leg bones. Increasing the distance between feeders and drinkers may be a method to increase locomotor activity under practical conditions and may be a method to reduce the incidence of leg disorders. Based on the results of previous experiments, a final test was carried out placing the feeder and drinker at two varied distances apart from each other (2 and 12 meters) and monitoring the effects on growth rate, locomotor activity, bone development and leg weakness in broilers. A total of 4800 male and female broilers (in groups of 600) were tested under virtually real conditions. The larger distance between food and water led to a three times increased level of locomotor activity. Weight development and food utilisation were not negatively influenced. Groups of birds, whose food and water supply were placed 12 metres apart, had significantly less cases of leg weakness and deaths due to leg disorders (2%). Increased walking activated the bone building processes of the tibia. This method is a practical way for broiler farmers to decrease leg weakness.

Objective: To report clinical experience with autogenous bone grafting, with and without metallic implants, for treatment of lameness attributed to incomplete ossification of the humeral condyle (IOHC)., Study Design: Case series., Animals: Dogs (n=8; 9 elbows) with IOHC., Methods: A transcondylar humeral bone core was removed and the resultant socket grafted using autogenous bone harvested as either free cancellous bone or a corticocancellous dowel using an osteochondral autograph transfer system. In 8 elbows, additional support for the humeral condyle was provided with metallic implants. Postoperative outcome was assessed by clinical, radiographic, computed tomographic (CT) and owner questionnaire examinations in the short and medium term., Results: Eight dogs (9 elbows) were treated surgically for IOHC. Graft types were free cancellous graft (n=2) or corticocancellous dowel (7). Condylar augmentation was performed using epicondylar cross pins (1); transcondylar Acutrak (AT) screw and epicondylar cortical screw (1); and a single transcondylar AT screw (7). Lameness resolved in 1-12 weeks. Bone bridging was documented in 7 of 8 elbows assessed by CT examination. Owner questionnaires (6 dogs) assessing daily functions were available for 7 of 9 elbows (follow-up, 6-45 months). Relevant follow-up function scores were significantly improved compared with preoperative values. One dog was intermittently lame and was administered nonsteroidal antiinflammatory medication., Conclusion: Use of autogenous bone grafting techniques leads to resolution of lameness attributed to IOHC. Augmentation of grafts with implants like the AT screw is recommended., Clinical Relevance: Autogenous bone grafting techniques represent a viable alternative or adjunct to existing techniques for clinical management of IOHC in the dog.