Effects of Alendronate on A Disintegrin and Metalloproteinase with Thrombospondin Motifs Expression in the Developing Epiphyseal Cartilage in Rats

A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been reported to play a role in the degradation of aggrecan, a major component of cartilage. This study was performed to examine the effects of alendronate on the expression of ADAMTS in developing femoral epiphyseal cartilage. Primary cultured chondrocytes from this cartilage were treated with alendronate in vitro and postnatal day 1 rats were injected subcutaneously with alendronate (1 mg/kg) every second day in vivo . The number of cultured chondrocytes and their aggrecan mRNA levels were unaffected by the alendronate treatment at 10⁻⁶ to 10⁻⁴  m concentrations. The mRNA levels of ADAMTS-1, -2 and -9 in chondrocytes were also unaffected. However, the levels of ADAMTS-5 and -4 were reduced significantly by the same treatment. The thickness of the proliferating chondrocyte layers and the aggrecan mRNA levels in the epiphysis were unaffected by the alendronate treatment in vivo . However, the hypertrophied chondrocyte layers became significantly thicker, and the size of the secondary ossification centre was reduced significantly by the same treatment ( P  < 0.05). Both ADAMTS-4 and -5 mRNA expressions were also reduced significantly in vivo . The immunoreactivity against ADAMTS-4 was seen in hypertrophied chondrocytes and reduced significantly by the alendronate treatment. These results suggested that alendronate can inhibit the degradation of aggrecan in the articular cartilage by downregulating the expression of matrix enzymes such as ADAMTS-4 and -5.     

Mapping of Split-Line Pattern and Cartilage Thickness of Selected Donor and Recipient Sites for Autologous Osteochondral Transplantation in the Canine Stifle Joint

Objective— To characterize donor and recipient sites for autologous osteochondral transplantation in the canine stifle joint with respect to split-line pattern and cartilage thickness.
Study Design— In vitro study.
Sample Population— Stifle joints (n=30) of dogs >20 kg.
Methods— Collagen network orientation of the hyaline cartilage coverage of the distal femur was assessed using split-line technique (n=10). Cartilage thickness was measured radiographically on osteochondral plugs harvested at the abaxial and axial surfaces of the femoropatellar joint (n=15), the most proximal abaxial aspect of the medial condyle (CO; n=5) and at both femoral condyles (n=15).
Results— Cartilage within the femoropatellar joint and both femoral condyles had mostly transversely orientated pattern of split-lines. Abaxial to the femoropatellar joint split-lines were absent. All donor sites had significantly thinner cartilage than the medial condyle (CM). Only the distal trochlea had cartilage thickness comparable to the lateral condyle (CL). The thinnest cartilage was found abaxial to the femoropatellar joint followed by CO, which was ∼2–3 times thinner than the cartilage at both condyles.
Conclusions— None of the investigated donor sites provided transplants of comparable cartilage thickness to CM. Transplants from within the femoropatellar joint should be harvested in priority as they reach cartilage morphology comparable to CL.
Clinical Relevance— Adjusting for cartilage thickness and split-line pattern may improve long-term outcome after autologous osteochondral transplantation. But surface curvature and donor-site morbidity have to be considered as well when choosing the most suitable donor site.     

Comparison of radiofrequency treatment and mechanical debridement of fibrillated cartilage in an equine model.

OBJECTIVE: To compare a radiofrequency energy (RFE) prototype probe to mechanical debridement (MD) and a commercially available RFE system used for chondroplasty in the treatment of an experimentally created partial thickness cartilage lesion in horses. The study design was experimental, randomized complete block, n=8, using fifteen mature ponies. METHODS: Grade 2 to 3 cartilage lesions were prepared in both patellae. After 10 months duration, the injuries were used to study the effects of MD, a commercially available bipolar RFE device (CoVac 50; ArthroCare Corporation) and a prototype monopolar RFE device (Smith & Nephew Endoscopy). Six months after treatment the patellae were examined for chondrocyte viability and cartilage structure. RESULTS: Mean depth of cell death was significantly different among groups (controls, MD 相似文献   

Blood flow distribution in hind limb bones and joint cartilage from young growing pigs.

Blood flow distribution was studied in hind limb bones and joint cartilage from four ten week old and four 20 week old pigs using 141Ce-microspheres. In general, blood flow rate was greater in the epiphyseal and metaphyseal cancellous bone than in the cortical bone and joint cartilage. In the epiphyseal cancellous bone, blood flow rate was three to tenfold greater (P less than 0.01) in the surface 2 mm layer than in the remaining deeper bone in all femoral and tibial samples examined. In the joint cartilage, blood flow rate in the femoral condyle was greater (P less than 0.05) than in the proximal femur, patella, central tarsus and metatarsus in ten week old pigs, and was greater (P less than 0.05) in the femoral condyle than in the patella and metatarsus in 20 week old pigs. A significant (P less than 0.05) age-associated decrease in the rate of blood flow was observed in the femoral, patellar and metatarsal cartilage. Within the femoral condyle, no differences in blood flow were found between areas associated with relatively high versus relatively low incidences of osteochondrosis.     

Effects of dietary supplementation of Acanthopanax senticosus on gastrointestinal tract development in calves

Twenty‐four newborn Holstein dairy male calves (with initial body weight of 38 ± 3.0 kg) were used in a randomized block design experiment to determine effects of dietary supplementation of Acanthopanax senticosus (AS) on gastrointestinal tract development. Calves were fed milk (10%/body weight) three times at 06.00, 12.00 and 18.00 hours daily with one to four treatments during the experimental periods (4 to 28 days): no supplementation of AS (control group, CG); 1.0 g/L?time of micro‐powder AS (MP); 1.0 g/L?time of superfine powder AS (SP); or 1.0 g/L?time of coarse powder AS (CP). On days 7, 14, 21 and 28, 20 mL blood samples were collected at 06.00 hours before the morning feeding. At the end of the trial (28 days), all calves were euthanized, and tissue samples were taken and placed in 4% buffered formaldehyde for analyses. In the rumen of MP treatment, compared with the CG treatment, wall thickness and papillae diameter was both significantly lower (P <0.05), while crypt depth was significantly greater (P <0.05). In the duodenum, villi diameter of AS supplemented treatments was significantly lower than that of CG treatment (P <0.05) . Results indicate that calves during sucking period supplemented with AS as MP style could promote gastrointestinal development.     

Effect of polysulfated glycosaminoglycan on DNA content and proteoglycan metabolism in normal and osteoarthritic canine articular cartilage explants

OBJECTIVE: To study the effect of polysulfated glycosaminoglycan (PSGAG) on proteoglycan metabolism and DNA content of control and osteoarthritic (OA) cartilage. STUDY DESIGN: An in vitro study comparing the effects of PSGAG on articular cartilage explants from canine stifle joints with and without chronic OA after transection of the left cranial cruciate ligament. SAMPLE POPULATION: Five large cross-breed dogs. METHODS: Cartilage explants (6 to 13 per treatment group) from the medial side of the femoral trochlea and medial femoral condyle from both stifles of each dog were incubated in a defined medium containing 0, 0.05, 0.5, or 5 mg/mL of PSGAG. After 72 hours in culture, explants were pulsed for 6 hours with sodium [35S]sulfate. Aminophenylmercuric acetate (APMA) was used to activate endogenous neutral matrix metalloproteinases (MMPs) and induce proteoglycan degradation in the radiolabeled explants. DNA content and radioactivity were measured in papain-digested explants, and radioactivity was measured in the medium by liquid scintillation counting. Proteoglycan synthesis and degradation were calculated. Cartilage was examined histologically for signs of OA. A mixed model analysis of variance and linear contrasts were used to test for significant (P < .05) effects of OA and treatment with PSGAG. RESULTS: Transection of the cranial cruciate ligament produced OA in operated joints. DNA content and proteoglycan synthesis of OA cartilage were significantly lower than in cartilage from control joints. For both DNA content and proteoglycan synthesis, significant interactions occurred between the concentration of PSGAG and whether the articular cartilage was from OA or control joints. The two lower concentrations of PSGAG (0.05 and 0.5 mg/mL) predominantly increased DNA content in OA cartilage (7 and 18%, respectively, compared with 0 mg/mL PSGAG) while the highest concentration (5 mg/mL) predominantly increased DNA content in control cartilage (30% compared with 0 mg/mL PSGAG). PSGAG at .05 mg/mL predominantly decreased proteoglycan synthesis in OA cartilage (19% reduction compared with 0 mg/mL PSGAG) while PSGAG at .5 and 5 mg/mL predominantly decreased proteoglycan synthesis in control cartilage (17 and 55% reduction, respectively, compared with 0 mg/mL PSGAG). Following activation of MMPs, PSGAG caused a dose-dependent decrease in degradation of radiolabeled proteoglycan in both OA and control cartilage. CONCLUSIONS: OA cartilage was responsive to treatment with PSGAG at 100-fold lower concentration than control cartilage. When treated with PSGAG, articular cartilage explants maintained or increased DNA content at the expense of proteoglycan synthesis. Following MMP activation, proteoglycan degradation was inhibited in OA and control explants in a dose-dependent manner. CLINICAL RELEVANCE: If the results of this study extend to in vivo use, treatment with PSGAG may modify the progression of OA in articular cartilage by maintaining chondrocyte viability or stimulating chondrocyte division as well as protecting against extracellular matrix degradation.     

Effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs

Two experiments were conducted to investigate the effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs. In experiment 1, the dietary treatments were (i) CON (CP 19.5%) and (ii) T1 (CP 16.0%). In feces samples, NH₃, H₂S, acetic acid and butyric acid emissions during the T1 treatment were lower than during the CON treatment ( P  < 0.05). In feces-urine samples, NH₃ emission during the T1 treatment was lower than during the CON treatment ( P  < 0.05). In experiment 2, 28 crossbred (Landrace × Yorkshire × Duroc) pigs (13.58 ± 0.10 kg) were used for a 42-day growth trial. Throughout the entire experimental period, ADG and ADFI of the CON treatment were higher than the T1 treatment ( P  < 0.05). On day 14, N digestibility in pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). On days 28 and 42, DM digestibility of the CON diet was greater than the T1 treatment ( P  < 0.05). On dat 42, serum BUN concentration of pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). In conclusion, these results indicate that reduction in dietary CP concentration decreased NH₃, H₂S and VFA emissions in feces and growth performance in nursery pigs.     

Effects of glycosaminoglycan polysulfate treatment on soundness, hyaluronic acid content of synovial fluid and proteoglycan aggregate in articular cartilage of lame boars.

Eighteen lame boars were equally assigned to two treatment groups based on initial bodyweight and leg soundness. The boars were injected intramuscularly with an aqueous solution of glycosaminoglycan polysulfate or saline on day 0, 5, 10, 15, 20 and 25 and killed on day 27. The glycosaminoglycan polysulfate treatment significantly (P less than 0.05) improved leg soundness score, and resulted in an increase (P less than 0.06) in the hyaluronic acid concentration of the cubitus joint synovial fluid, and an increase (P less than 0.05) in the proportion of aggregated proteoglycans in the articular cartilage of the medial femoral condyle. Feed intake, growth rate and articular cartilage soundness score for the cubitus and stifle joints were not significantly (P greater than 0.10) affected by the treatment.     

Treatment of subchondral cystic lesions of the medial femoral condyle of mature horses with growth factor enhanced chondrocyte grafts: a retrospective study of 49 cases

Reasons for performing study: To evaluate the long‐term clinical outcome after allogeneic chondrocyte and insulin‐like growth factor‐I (IGF‐I) grafting of subchondral cystic lesions (SCLs) of the femoral condyle in horses. Objective: To test the hypothesis that chondrocyte and IGF‐I grafts will improve the long‐term clinical outcome in arthroscopically debrided SCLs. Methods: Medical records of 49 horses with SCLs of the femoral condyle treated by debridement and implantation of chondrocytes and IGF‐I were reviewed. Preoperative radiographs were obtained, and caudocranial radiographic projections were used to establish a ratio between cyst and femoral condyle size. Arthroscopic cyst debridement followed by filling of the bone void with autologous cancellous bone (45 horses) or tricalcium phosphate granules (4 horses) was performed. A paired syringe containing a fibrinogen and chondrocyte mixture in one syringe and calcium‐activated bovine thrombin with IGF‐I in the other was used to cover the surface. A successful outcome was defined as a horse that performed to its intended use without lameness. Results: A successful outcome was achieved in 36 of 49 horses (74%). Preoperative radiography was performed in all horses, with 33 horses having unilateral SCLs of the medial femoral condyle, 15 horses having bilateral SCLs of the medial femoral condyle, and one horse having bilateral SCLs of the lateral femoral condyle. Median age of the horses was 3.3 years. Fifteen horses had preoperative radiographic and arthroscopic evidence of osteoarthritis (OA). A successful outcome was not influenced by age of horse, presence of pre‐existing osteoarthritis or preoperative size of the subchondral cyst. Grafting resulted in success for 80% of horses >3 years old, and in 80% of horses with OA. Conclusions: Implantation of allogeneic chondrocytes supplemented with IGF‐I is an effective treatment for horses with SCLs of the femoral condyle, and particularly for older horses and horses with pre‐existing osteoarthritis. Potential relevance: Chondrocyte implantation may offer a greater chance of long‐term success in older horses and horses with osteoarthritis than has been previously reported with cyst debridement alone.     

Experimental rickets in broilers: gross, microscopic, and radiographic lesions. III. Vitamin D deficiency

Day-old broiler chicks were fed a vitamin D-deficient diet for 30 days. Gross, microscopic, and radiographic examinations of the proximal tibiotarsus were done at 2, 3, and 4 weeks of age. In 2-week-old chicks, there was variable lengthening and disorganization of the proliferating-prehypertrophied zone (P-PHZ), resorption of cartilage spicules in the degenerating hypertrophied zone and primary spongiosa, and lengthening of bone spicules in the secondary spongiosa; many bone surfaces were lined with increased osteoid. In 3-week-old chicks, there was a tendency for the P-PHZ to decrease in relative length and for cartilage spicules to increase in length. In 4-week-old chicks, however, there was marked lengthening of the P-PHZ, resorption of cartilage spicules, and replacement of the metaphysis with irregularly oriented islands of woven bone, osteoid, and loose fibrous connective tissue.     

A study on feeding hazelnut kernel oil meal as a protein source for broiler chickens

An experiment was conducted to evaluate the effect of substituting different levels of hazelnut kernel oil meal (HKM) for soybean meal (SBM) in diets for broiler. A total of 450 one-day-old female Ross 308 broiler chicks were allocated randomly to three treatment groups of 150 birds each in a randomized design. Each treatment group consisted of five replicates each of 30 chicks. All diets (in mash form) were formulated to meet nutrient concentrations recommended for broilers. The experiment lasted for six weeks. In the experiment, an SBM control (SBM) diet was compared to two HKM diets, replacing 50 (50HKM) and 100% (HKM) of SBM protein, respectively. Body weight gain, feed intake and feed conversion ratio of broilers were adversely affected ( P  < 0.05) by the HKM diets at 42 days of age. Broilers fed 50HKM and HKM had growth performances similar ( P  > 0.05). The carcass yield and abdominal fat pads of birds fed diets with SBM were higher ( P  < 0.05) than those of chicks fed the 50HKM and HKM diets. The edible inner organ weight of chicks fed diets with HKM was the heaviest ( P  < 0.05). It is concluded that SBM cannot be replaced even up to 50% with HKM in commercial broiler diet.     

Age related changes and osteochondrosis in swine articular and epiphyseal cartilage: light ane electron microscopy.

Age related changes and osteochondrosis in swine were studied using light microscopy and electron microscopy in articular cartilage and light microscopy and epiphyseal cartilage of swine from three days to 30 weeks of age. Thickness, cellularity and vascularity of both the epiphyseal and articular cartilage, decreased as the swine aged. Osteochondrotic changes included formation of "plugs" of cartilage indicating localized failure of ossification and separation and space formation in epiphyseal cartilage. Eosinophilic streaks and space formation in epiphyseal cartilage was observed in relation to epiphyseal separation. Electron microscopy showed a continuous fibrillar layer on the surface of the cartilage corresponding to the lamina splendens of light microscopy. This layer increased in the thickness and showed accumulation of amorphous material between the fibrils with aging. In the matrix, the orientation and distribution of the collagen fibers changed with growth and thicker fibers with clear sub banding were more common in older age groups. Also, necrotic cells, glycogen containing bodies and cellular debris were noticed in the matrix of normal cartilage in old animals. Chondrocytes in the younger cartilage showed accumulation of organelles responsible for protein synthesis; while Golgi bodies, vesicles, lysosomes, well developed foot processes and other inclusions were noticed in older cartilage. Cartilage erosions had a clumped and disrupted lamina splendens on the surface and electron lucent patches in the ground substances of the matrix and chondrocyte cytoplasm.     

Effects of GH gene polymorphism and sex on carcass traits and fatty acid compositions in Japanese Black cattle

To investigate the effects of bovine growth hormone (bGH) gene polymorphism on carcass traits and fatty acid compositions in Japanese Black cattle caused by nucleotide substitution of CTG (allele A)/GTG (allele B) at codon 127 and of ACG (allele A and B)/ATG (allele C) at codon 172 of bGH, GH genotypes of 135 cattle were determined using allele specific-multiplex polymerase chain reaction (PCR). Allele A gave greater rib thickness and lower melting point of fat (MP) while allele B gave higher C18:1% ( P  < 0.05). Allele C gave higher C18:1, monounsaturated fatty acid (MUFA), unsaturated fatty acid (USFA) percentages ( P  < 0.05). It also gave lower saturated fatty acid (SFA) percentages, higher MUFA/SFA and USFA/SFA ratios, and lower MP ( P  < 0.05). Interactions of sex and GH alleles were analyzed. In heifers, allele A gave higher carcass weight, daily carcass gain, rib eye area, rib thickness, subcutaneous fat thickness, and BMS while allele B gave greater rib eye area and rib thickness ( P  < 0.05). Allele C gave higher C18:1 ( P  < 0.01), MUFA ( P  < 0.01), USFA percentages ( P  < 0.05) and MUFA/SFA and USFA/SFA ratios ( P  < 0.01), and lower C16:0 and SFA percentages ( P  < 0.05) and MP ( P  < 0.01). GH gene polymorphism affected carcass traits and fatty acid compositions although the effects were more pronounced in heifers.     

Interleukin-1beta and tumor necrosis factor-alpha produce distinct, time-dependent patterns of acute arthritis in the rat knee

Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) synergistically induce and sustain arthritis. Two competing hypotheses of arthritis induction are 1) that TNF preferentially mediates inflammation, whereas IL-1 impels bone destruction, or 2) that either cytokine controls the entire process. In this study, these propositions were tested in two experiments by instilling IL-1beta or TNF-alpha into one knee of Lewis rats (n = 6/group) to incite arthritis, after which semiquantitative scores for inflammation, bone resorption, osteoclasts, and cartilage integrity were acquired. In the induction study, IL-1beta or TNF-alpha (3, 10, or 30 micro g) was given once to incite arthritis. After 2 days, IL-1beta induced significant, dose-dependent increases in inflammation (mild to marked), bone resorption (minimal to moderate), and osteoclasts (minimal to moderate). In contrast, TNF-alpha induced minimal to mild inflammation but had little impact on resorption or osteoclasts. Both IL-1 and TNF (>/=10 micro g) yielded mild cartilage degeneration. Most lesion scores in TNF-treated rats were significantly lower than those in animals given the same dose of IL-1beta. In the persistence study, rats were injected once with IL-1 or TNF (10 micro g) and maintained for 2, 3, or 7 days. IL-1beta significantly enhanced inflammation (all 3 days), bone resorption (days 2 and 3), osteoclasts (days 2 and 3), and cartilage matrix loss (days 2 and 3), whereas TNF-alpha augmented inflammation (days 2 and 3) and cartilage degeneration (day 2) but not bone resorption or osteoclasts. Thus, both IL-1beta and TNF-alpha can launch inflammation, but IL-1beta drives skeletal destruction.     

Kinematic analysis of equine masticatory movements: comparison before and after routine dental treatment

The objective of this study was to compare masticatory movements before and after dental treatment using kinematic analysis. The masticatory movements of 15 adult Warmblood horses with mild dental pathology chewing standardised hay were recorded on three consecutive days before and three times after (days 7, 21, 28) dental correction. The results of the leading mandibular tracking marker, located at the caudal edge of the inter-mandibular suture, were compared statistically. Reproducibility of measurements prior to dental treatment was excellent (P<0.05). Rostrocaudal mandibular motion was significantly reduced after dental correction (9±2mm vs. 8±2mm; P=0.046). Oscillations during the power stroke were significantly reduced after dental correction (R(2)=98.3%±0.3 vs. 98.8%±0.3; P=0.050). Although significant changes were observed in individual horses, the overall results of lateral and dorsoventral mandibular motion did not reveal significant differences. In conclusion, kinematic analysis of masticatory movements provided reproducible results and may be useful to evaluate changed movement patterns following dental correction.     

Comparison of the effects of caudal pole hemi-meniscectomy and complete medial meniscectomy in the canine stifle joint

OBJECTIVE: To compare the effects of caudal pole hemi-meniscectomy (CPHM) and complete medial meniscectomy (MM), specifically with respect to development of secondary osteoarthritis, in the stifle joints of clinically normal dogs. ANIMALS: 14 large-breed dogs. PROCEDURE: Unilateral CPHM (7 dogs) or MM (7) was performed, and the left stifle joints served as untreated control joints. Gait was assessed in all dogs before surgery and at 4, 8, 12, and 16 weeks postoperatively. After euthanasia, joints were evaluated grossly; Mankin cartilage scores, subchondral bone density assessment, and articular cartilage proteoglycan extraction and western blot analyses of 3B3(-) and 7D4 epitopes were performed. RESULTS: Weight distribution on control limbs exceeded that of treated limbs at 4 and 16 weeks after surgery in the CPHM group and at 4 and 8 weeks after surgery in the MM group; weight distribution was not significantly different between the 2 groups. After 16 weeks, incomplete meniscal regeneration and cartilage fibrillation on the medial aspect of the tibial plateau and medial femoral condyle were detected in treated joints in both groups. Mankin cartilage scores, subchondral bone density, and immunoexpression of 3B3(-) or 7D4 in articular cartilage in CPHM- or MM-treated joints were similar; 7D4 epitope concentration in synovial fluid was significantly greater in the MM-treated joints than in CPHM-treated joints. CONCLUSIONS AND CLINICAL RELEVANCE: Overall severity of secondary osteoarthritis induced by CPHM and MM was similar. Investigation of 7D4 epitope concentration in synovial fluid suggested that CPHM was associated with less disruption of chondrocyte metabolism.     

Osteochondral Dowel Transplantation for Repair of Focal Defects in the Knee: An Outcome Study Using an Ovine Model

Objective—A model system was developed to objectively assess the quality of articular cartilage after surgical reconstruction of focal defects in the medial femoral condyle using osteochondral dowel grafts.
Study Design—The surgical technique was developed and customized to reproducibly minimize surgical trauma and graft instability in order to improve the survival of the transplanted cartilage and the long-term integrity of the joint surfaces.
Animals or Sample Population—24 adult female Suffolk-Romanoff crossbred sheep.
Methods—Biomechanical creep testing, paravital staining for chondrocyte viability, histological analysis, and gross morphological analysis were performed at 3, 6, and 12 months postoperatively to compare fresh autografted osteochondral dowels with allografts that had been subject to a freezing protocol known to kill chondrocytes. The latter was used to investigate the time course of cartilage degeneration after injury. These two groups were also compared with normal unoperated control tissue.
Results—Biomechanical behavior, chondrocyte survival, and cartilage histology differed significantly between fresh grafts and those that had been frozen.
Conclusions —Indentation testing and paravital staining were able to identify degenerative changes earlier than other methods of assessment. The technique developed here reproducibly and reliably transplanted osteochondral dowel grafts while minimizing the confounding effects of surgical trauma and graft instability.
Clinical Relevance —The technique provides both a promising surgical technique for the repair of focal defects of the medial femoral condyle and a sensitive model for the future study of cryopreservation strategies for articular cartilage.     

Effect of a novel topical diester glucocorticoid spray on immediate- and late-phase cutaneous allergic reactions in Maltese–beagle atopic dogs: a placebo-controlled study

The inhibitory effect of 0.0584% hydrocortisone aceponate spray on immediate- and late-phase skin reactions and the duration of inhibition after medication withdrawal were studied in 10 Maltese-beagle atopic dogs. All subjects were sprayed on axillary and inguinal regions and on one randomly chosen side of the thorax once daily for 14 (phase 1) or 7 days (phase 2). Intradermal injections (IDT) of histamine and anticanine IgE antiserum were performed bilaterally on the thorax before, 7 and 14 days after treatment. During phase 2, IDT was performed once weekly for 5 weeks. Each IDT was evaluated by an investigator blinded to the site of active treatment. Skin biopsies of 24-h anti-IgE-associated late-phase reactions were collected from both thoracic sides before and 14 days after treatment to determine the number of inflammatory cells and dermal thickness. Phase 1 : Histamine and anti-IgE-induced global wheal scores at treated sites were significantly lower after 7 and 14 days with negative reactions present in >90% of dogs. Late-phase reactions at both sides were also significantly decreased compared with that at baseline, and this was associated with reduced inflammatory cell influx. Moreover, a significant decrease in dermal thickness was recorded at treated sides after 14 days. Phase 2 : Histamine reactions became positive at untreated sides in all dogs 2 weeks after treatment. In conclusion, the 0.0584% hydrocortisone aceponate spray significantly decreased immediate- and late-phase IDT reactions, and prolonged application caused skin atrophy at treated sites. A 2-week withdrawal period prior to IDT is proposed.     

Effect of diet on longitudinal bone growth and osteochondrosis in swine

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

Temporomandibular joint injuries and ankylosis in the cat

Objective: To evaluate cause, location, treatment, and the clinical outcome of traumatic temporomandibular joint (TMJ) lesions and TMJ ankylosis in cats. Methods: Cats with TMJ injuries were included in this study. Lesions were classified as luxations, fractures of the condylar process, and intra-articular temporal bone fractures. Signalment, cause and type of injuries, treatment methods, clinical outcome, complications and joint ankylosis were assessed and evaluated statistically. Results: Temporomandibular joint lesions were observed in 82 of 161 cats with maxillofacial injuries. One hundred forty-nine TMJ lesions were determined in 112 joints. Falling was the most common cause and fractures of the condylar process were the most common types of injuries. Isolated TMJ injuries and caudal TMJ luxations were mainly caused by falling. Condylectomy was used in ankylosis, chronic luxation, reluxation and in two cases with multiple TMJ lesions. Ankylosis was observed in 10.97% of cases and was generally observed in fracture combinations of condylar process and mandibular fossa (χ2 = 8.52; p <0.05). No significant relationship between age and development of ankylosis (χ2 = 3.995; p >0.05) was found. Conclusion: In contrast to previous studies, traumatic TMJ lesions were observed in a considerable amount of cats with maxillofacial injuries, and fractures of the condylar process were the most common type. Lesions caused by falling were mostly simple, whereas vehicular trauma caused more complicated lesions. Ankylosis did not appear as a rare condition. Any cat with TMJ injury is susceptible to the development of ankylosis.