Osteochondrosis in the central and third tarsal bones of young horses.

Recently, the central and third tarsal bones of 23 equine fetuses and foals were examined using micro-computed tomography. Radiological changes, including incomplete ossification and focal ossification defects interpreted as osteochondrosis, were detected in 16 of 23 cases. The geometry of the osteochondrosis defects suggested they were the result of vascular failure, but this requires histological confirmation.

Nerve growth factor receptors in equine synovial membranes vary with osteoarthritic disease severity.

Nerve growth factor (NGF) is a neurotrophin that has been implicated in pain signaling, apoptosis, inflammation and proliferation. The resultant effects depend on interaction with two different receptors; tyrosine kinase A (TrkA) and p75 . NGF increases in synovial fluid from osteoarthritic joints, and monoclonal antibody therapy is trialed to treat osteoarthritis (OA)-related pain.

Conditioned serum in vitro treatment of chondrocyte pellets and osteoarthritic explants.

Background: Autologous conditioned serum (ACS) is used to treat osteoarthritis in horses, although its effects are not fully investigated.

Objectives: To investigate the effects of equine serum and conditioned serum on chondrocytes stimulated with interleukin (IL)-1β and cartilage explants with mild osteoarthritis.

Study Design: In vitro experimental study.

Guided bone tissue regeneration using a hollow calcium phosphate based implant in a critical size rabbit radius defect.

Long bone fractures are common and sometimes difficult to treat. Autologous bone (AB), bovine bone and calcium phosphates are used to stimulate bone growth with varying results. In the present study, a calcium phosphate cement (CPC) that previously showed promising grafting capabilities was evaluated for the first time in a long bone defect.

The effect of housing environment on bone healing in a critical radius defect in New Zealand White rabbits.

In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.

Neuromas at the castration site in geldings.

Background: Inguinal pain, unexplained hind limb lameness, back pain or behavioural problems in geldings could be attributable to painful neuromas that develop as a consequence of crushing and severing the testicular nerves during castration. The presence of neuroma in this anatomical location has never been reported, hence the knowledge of possible clinical relevance is limited. The aim of this study was to histologically investigate the testicular nerves at the castration site in geldings for the presence of neuromas.

Observational Study Design in Veterinary Pathology, Part 2: Methodology.

Observational studies are a basis for much of our knowledge of veterinary pathology, yet considerations for conducting pathology-based observational studies are not readily available. In part 1 of this series, we offered advice on planning and carrying out an observational study. Part 2 of the series focuses on methodology.

Observational Study Design in Veterinary Pathology, Part 1: Study Design.

Observational studies are the basis for much of our knowledge of veterinary pathology and are highly relevant to the daily practice of pathology. However, recommendations for conducting pathology-based observational studies are not readily available. In part 1 of this series, we offer advice on planning and conducting an observational study with examples from the veterinary pathology literature.

Septic Arthritis/Osteomyelitis May Lead to Osteochondrosis-Like Lesions in Foals.

Failure of the cartilage canal blood supply leads to ischemic chondronecrosis which causes osteochondrosis, and osteochondral lesions. Osteochondrosis is a disease with a heritable component and usually occurs under aseptic conditions. Because bacteria can bind to growth cartilage and disrupt the blood supply in pigs and chickens, we considered whether this might play a role in development of equine osteochondrosis.

Time-dependent changes in gene expression induced in vitro by interleukin-1β in equine articular cartilage.

Osteoarthritis is an inflammatory and degenerative joint disease commonly affecting horses. To identify genes of relevance for cartilage pathology in osteoarthritis we studied the time-course effects of interleukin (IL)-1β on equine articular cartilage. Articular cartilage explants from the distal third metacarpal bone were collected postmortem from three horses without evidence of joint disease.

A new synthetic granular calcium phosphate compound induces new bone in a sinus lift rabbit model.

Objectives: The aim of this study was to investigate if a synthetic granular calcium phosphate compound (CPC) and a composite bisphosphonate-linked hyaluronic acid-calcium phosphate hydrogel (HABP·CaP) induced similar or more amount of bone as bovine mineral in a modified sinus lift rabbit model.

Material And Methods: Eighteen adult male New Zeeland White rabbits, received randomly one of the two test materials on a random side of the face, and bovine mineral as control on the contralateral side. In a sinus lift, the sinus mucosa was elevated and a titanium mini-implant was placed in the alveolar bone.

Biomarkers for equine joint injury and osteoarthritis.

We report the results of a symposium aimed at identifying validated biomarkers that can be used to complement clinical observations for diagnosis and prognosis of joint injury leading to equine osteoarthritis (OA). Biomarkers might also predict pre-fracture change that could lead to catastrophic bone failure in equine athletes. The workshop was attended by leading scientists in the fields of equine and human musculoskeletal biomarkers to enable cross-disciplinary exchange and improve knowledge in both.

Cartilage canals in the distal intermediate ridge of the tibia of fetuses and foals are surrounded by different types of collagen.

Some epiphyseal growth cartilage canals are surrounded by a ring of hypereosinophilic matrix consisting of collagen type I. Absence of the collagen type I ring may predispose canal vessels to failure and osteochondrosis, which can lead to fragments in joints (osteochondrosis dissecans). It is not known whether the ring develops in response to programming or biomechanical force.

Carprofen neither reduces postoperative facial expression scores in rabbits treated with buprenorphine nor alters long term bone formation after maxillary sinus grafting.

In connection with bilateral maxillary sinus augmentation, the acute effects of the nonsteroidal anti-inflammatory drug carprofen on facial expressions and long-term effects on bone formation were evaluated in 18 male New Zealand White rabbits. A 10×10mm bone window was drilled in the maxilla, the sinus membrane elevated and a titanium mini-implant inserted. One of two test materials was randomly inserted unilaterally and bovine bone chips (control) on the contralateral side in the created space.

Discontinuities in the endothelium of epiphyseal cartilage canals and relevance to joint disease in foals.

Cartilage canals have been shown to contain discontinuous blood vessels that enable circulating bacteria to bind to cartilage matrix, leading to vascular occlusion and associated pathological changes in pigs and chickens. It is also inconsistently reported that cartilage canals are surrounded by a cellular or acellular wall that may influence whether bacterial binding can occur. It is not known whether equine cartilage canals contain discontinuous endothelium or are surrounded by a wall.

Osteochondrosis, but not lameness, is more frequent among free-range pigs than confined herd-mates.

Background: Organic pig production is expanding and amongst the objectives of organic farming are enhancing animal health and welfare. However, some studies have reported a higher prevalence of lameness and joint condemnation at slaughter in free-range/organic pigs than in conventionally raised pigs. Organic slaughter pigs have free-range housing in which indoor and outdoor access is compulsory, while in conventional farming the pigs are commonly confined to indoor pens.

An inflammatory equine model demonstrates dynamic changes of immune response and cartilage matrix molecule degradation in vitro.

The molecular aspects of inflammation were investigated in equine articular cartilage explants using quantitative proteomics. Articular cartilage explants were stimulated with interleukin (IL)-1β in vitro for 25 days, and proteins released into cell culture media were chemically labeled with isobaric mass tags and analyzed by liquid chromatography-tandem mass spectrometry. A total of 127 proteins were identified and quantified in media from explants.

Effects of free-range and confined housing on joint health in a herd of fattening pigs.

Background: Free-range housing, in which pigs have access to both indoor and outdoor areas, is mandatory in organic pig production in Europe, but little is known about the effects of this housing on joint health in pigs. A high level of joint condemnations at slaughter has been reported in organic free-range pigs in Sweden, compared with pigs raised in conventional confined housing. We hypothesised that biomechanical forces imposed on the joints of pigs that range freely promote the development of osteochondrosis and lead to joint condemnation.

Cell and matrix modulation in prenatal and postnatal equine growth cartilage, zones of Ranvier and articular cartilage.

Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and to follow changes in matrix protein localisation during joint development.

Effects of interleukin-6 and interleukin-1β on expression of growth differentiation factor-5 and Wnt signaling pathway genes in equine chondrocytes.

Objective: To determine the effects of interleukin (IL)-6 and IL-1β stimulation on expression of growth differentiation factor (GDF)-5 and Wnt signaling pathway genes in equine chondrocytes.

Sample: Macroscopically normal articular cartilage samples from 6 horses and osteochondral fragments (OCFs) from 3 horses.

Procedures: Chondrocyte pellets were prepared and cultured without stimulation or following stimulation with IL-6 or IL-1β for 1, 2, 12, and 48 hours; expression of GDF-5 was determined with a quantitative real-time PCR assay.

Local Morphological Response of the Distal Femoral Articular-Epiphyseal Cartilage Complex of Young Foals to Surgical Stab Incision and Potential Relevance to Cartilage Injury and Repair in Children.

Objective: Describe the local morphological response of the articular-epiphyseal cartilage complex to surgical stab incision in the distal femur of foals, with emphasis on the relationship between growth cartilage injury, enchondral ossification, and repair.

Design: Nine foals were induced into general anesthesia at the age of 13 to 15 days. Four full-thickness stab incision defects were created in the cartilage on the lateral aspect of the lateral trochlear ridge of the left distal femur.

Evaluation of osteochondral sample collection guided by computed tomography and magnetic resonance imaging for early detection of osteoarthritis in centrodistal joints of young Icelandic horses.

Objective: To evaluate the use of CT and MRI for guidance of osteochondral sample collection for histologic detection of early osteoarthritic lesions in centrodistal (distal intertarsal) joints of horses.

Sample: Right tarsal joints from the cadavers of 24 Icelandic horses aged 29 to 31 months.

Procedures: CT and MRI were used to evaluate the extent of suspected osteoarthritic changes in centrodistal joints, which were graded with a semiquantitative system.

Immunolocalization of collagens (I and III) and cartilage oligomeric matrix protein in the normal and injured equine superficial digital flexor tendon.

This is a descriptive study of tendon pathology with different structural appearances of repair tissue correlated to immunolocalization of cartilage oligomeric matrix protein (COMP) and type I and III collagens and expression of COMP mRNA. The material consists of nine tendons from seven horses (5-25 years old; mean age of 10 years) with clinical tendinopathy and three normal tendons from horses (3, 3, and 13 years old) euthanized for non-orthopedic reasons. The injured tendons displayed different repair-tissue appearances with organized and disorganized fibroblastic regions as well as areas of necrosis.

Effects of high mobility group box protein-1, interleukin-1β, and interleukin-6 on cartilage matrix metabolism in three-dimensional equine chondrocyte cultures.

The effects of high mobility group box protein (HMGB)-1, interleukin (IL)-1β, and IL-6 on equine articular chondrocytes were investigated, with emphasis on detecting differences between anatomical sites exposed to different loading in vivo, using three-dimensional (3D) cell cultures established with chondrocytes from dorsal radial facet (DRF, highly loaded) and palmar condyle (PC, less loaded) of the third carpal bone (C3). Expression of important genes involved in cartilage metabolism, presence of glycosaminoglycans and cartilage oligomeric matrix protein (COMP) in pellets, and concentrations of matrix metalloproteinase (MMP)-13 and aggrecan epitope CS 846 were evaluated. Compared to controls, IL-1β treatment increased gene expression of versican, matrix-degrading enzymes, and tissue inhibitor of metalloproteinase (TIMP)-1, and decreased aggrecan and collagen type I and type II expression.

Retinal degeneration in nine Swedish Jämthund dogs.

The Jämthund is the fourth most common breed in Sweden with approximately 1600 pups registered each year. Although it has been known that some adult dogs go blind, so they cannot hunt, the Jämthund dog has historically not been screened for hereditary eye diseases. This report describes nine Swedish Jämthund dogs with retinal degeneration.