Owner assessed outcomes following elbow arthroscopy with or without platelet rich plasma for fragmented medial coronoid process.

Objective: Document the outcomes of bilateral arthroscopic subtotal coronoidectomy for the fragmented medial coronoid process, quantify persistent lameness that required additional treatment (PRP), and document the outcomes of dogs that followed up with PRP injections. Study design: Retrospective study. Sample population: Overall, 115 dogs underwent arthroscopy alone and 31 received PRP at least 6 weeks after arthroscopy. The owner's response rate was ~50% (73 dogs). Methods: Collected data included signalment, unilateral or bilateral clinical signs, intra-articular chondroprotective injection during the procedure, if PRP intra-articular injection was received postoperatively, and if it was received, the time from the initial surgery to administration was recorded. Outcomes were assessed via standardized owner questionnaires using the Liverpool Osteoarthritis in Dogs (LOAD) score, the Canine Brief Pain Inventory (CBPI) score, and the overall quality of life (QOL) assessment. Results: Approximately 20% of the patients received PRP post-operatively due to persistent lameness following surgery. Similar pain scores were found between the two groups with an average of 11-13 LOAD score, 13-15 CBPI score, and good quality of life. Older animals at the time of surgery and those that received pain-relieving medications after the procedure were more painful and affected their functional outcome. PRP as an adjunctive therapy achieved a perceived good to excellent quality of life in ~90% of pets in this population. Conclusion: Arthroscopy and subtotal coronoidectomy followed by PRP, if needed, seemed to decrease pain, and improve lameness in the long term. Clinical significance: PRP should be considered as adjunctive therapy in dogs with the limited response to arthroscopy alone.

Assessment of dermal absorption of aluminium from a representative antiperspirant formulation using a (26Al)Al microtracer approach: a follow-up study in humans.

A follow-up study was performed in 12 healthy women to evaluate systemic exposure to aluminium following topical application of a representative antiperspirant formulation under real-life use conditions (part A) and to assess the local fate of topically applied aluminium by taking additional tape strips and skin biopsies (Part B). A simple roll-on formulation, containing the maximal possible radioactive dose, was prepared with [26Al] aluminium-labeled chlorohydrate (ACH). The microtracer of [26Al] was used to distinguish aluminium from the natural background, using accelerator mass spectrometry. [26Al] aluminiumcitrate was administered intravenously to estimate the dermal fraction absorbed. Despite the 25-fold increase of the topical dose compared with the previous study, only 12 blood samples gave results above the lower limit of quantitation (0.118 fg/mL). The most reliable estimates of the dermal fraction absorbed are derived from noncompartmental analysis with the urine data. By using the intravenous dose to normalize the urinary excretion to 100% bioavailability, the best estimate of the fraction absorbed of [26Al] from a topical application of [26Al]-aluminium-labeled chlorohydrate in an antiperspirant formulation was 0.00052%. Part B of the study demonstrated that the majority of the aluminium in the formulation remained associated with the external layers of the skin without penetration through the skin.

Effects of carbon dioxide on growth of proteolytic Clostridium botulinum, its ability to produce neurotoxin, and its transcriptome.

The antimicrobial gas carbon dioxide is frequently used in modified atmosphere packaging. In the present study, the effects of CO2 (10 to 70%, vol/vol) on gene expression (measured using quantitative reverse transcription-PCR and a whole-genome DNA microarray) and neurotoxin formation (measured using an enzyme-linked immunosorbent assay [ELISA]) by proteolytic Clostridium botulinum type A1 strain ATCC 3502 were studied during the growth cycle. Interestingly, in marked contrast to the situation with nonproteolytic C. botulinum types B and E, CO2 had little effect on any of these parameters. At all CO2 concentrations, relative expression of neurotoxin cluster genes peaked in the transition between exponential and stationary phases, with evidence of a second rise in expression in late stationary phase. Microarray analysis enabled identification of coding sequences whose expression profiles matched those of the neurotoxin cluster. Further research is needed to determine whether these are connected to neurotoxin formation or are merely growth phase associated.

Severity of patellar luxation and frequency of concomitant cranial cruciate ligament rupture in dogs: 162 cases (2004-2007).

OBJECTIVE: To evaluate severity of medial patellar luxation (MPL) and frequency of concomitant cranial cruciate ligament rupture (CCLR) in dogs. DESIGN: Retrospective case series. ANIMALS: 162 dogs (266 stifle joints). PROCEDURES: Medical records of 162 small-breed dogs with MPL were reviewed. Signalment, body weight, luxation grade, bilateral or unilateral MPL, CCLR, and difference in luxation grades between stifle joints were evaluated. Association between severity of MPL and CCLR was investigated. RESULTS: 58 dogs had unilateral MPL, and 104 dogs had bilateral MPL. Dogs ranged from 8.4 months to 16.7 years of age (mean, 5.7 years), and mean body weight was 5.45 kg (12 lb). Forty-one percent of all dogs had concomitant CCLR. Mean age for dogs with MPL alone was 3.0 years, which differed significantly from mean age of dogs with MPL and concomitant CCLR (7.8 years). Dogs with grade IV MPL were significantly more likely to have concomitant CCLR than were dogs with any other grade of MPL. In dogs with bilateral MPL and unilateral CCLR, there was a significantly higher grade of luxation in the stifle joint with CCLR. CONCLUSIONS AND CLINICAL RELEVANCE: Small-breed dogs with MPL and concomitant CCLR were older than were dogs with only MPL. Dogs with grade IV MPL were more likely to have CCLR than were dogs with other grades of MPL. Most dogs with concomitant CCLR had a higher MPL grade in the affected stifle joint than in the intact joint. These findings should be beneficial in client education and clinical diagnosis.

An analysis of the quality of canine cranial cruciate ligament disease information available on the Internet.

OBJECTIVE: To assess the quality of information available on the Internet pertaining to canine cranial cruciate ligament (CCL) disease. STUDY DESIGN: Survey Study. METHODS: Three search phrases were entered separately into 5 search engines and the 1st page of websites from each search was analyzed. Unique websites were evaluated by 3 Diplomates of the American College of Veterinary Surgeons using standardized scales for content and information value score (IVS). Websites were further categorized by veterinary or non-veterinary authorship. The readability of each website was scored using a proven literacy scale (Flesch-Kinkaid system). RESULTS: Fifty-four unique websites were evaluated. Websites located using anatomically correct veterinary terminology had significantly (P<.05) higher ratings for content and IVS compared with those found using lay terminology. Websites authored by veterinarians also had significantly (P<.05) higher IVS compared with those authored by non-veterinarians. Websites found using anatomically correct veterinary terminology, and those authored by veterinarians, had significantly (P<.05) lower readability scores, requiring a higher literacy level for comprehension. CONCLUSIONS: Information available on the Internet with respect to canine CCL disease is of highly variable quality. Use of anatomically correct veterinary terminology when conducting an Internet search detects sites with higher quality information; however, a higher literacy level is required to understand the material. Similarly, websites authored by veterinarians are more likely to present higher quality information, but require a more advanced literacy level for comprehension. CLINICAL RELEVANCE: CCL disease information on the Internet is of variable quality and can be misleading.

Independent evolution of neurotoxin and flagellar genetic loci in proteolytic Clostridium botulinum.

BACKGROUND: Proteolytic Clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. Given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of C. botulinum. The recent determination of the genome sequence of C. botulinum has allowed comparative genomic indexing using a DNA microarray. RESULTS: Whole genome microarray analysis revealed that 63% of the coding sequences (CDSs) present in reference strain ATCC 3502 were common to all 61 widely-representative strains of proteolytic C. botulinum and the closely related C. sporogenes tested. This indicates a relatively stable genome. There was, however, evidence for recombination and genetic exchange, in particular within the neurotoxin gene and cluster (including transfer of neurotoxin genes to C. sporogenes), and the flagellar glycosylation island (FGI). These two loci appear to have evolved independently from each other, and from the remainder of the genetic complement. A number of strains were atypical; for example, while 10 out of 14 strains that formed type A1 toxin gave almost identical profiles in whole genome, neurotoxin cluster and FGI analyses, the other four strains showed divergent properties. Furthermore, a new neurotoxin sub-type (A5) has been discovered in strains from heroin-associated wound botulism cases. For the first time, differences in glycosylation profiles of the flagella could be linked to differences in the gene content of the FGI. CONCLUSION: Proteolytic C. botulinum has a stable genome backbone containing specific regions of genetic heterogeneity. These include the neurotoxin gene cluster and the FGI, each having evolved independently of each other and the remainder of the genetic complement. Analysis of these genetic components provides a high degree of discrimination of strains of proteolytic C. botulinum, and is suitable for clinical and forensic investigations of botulism outbreaks.

Comparative genomic hybridization analysis of two predominant Nordic group I (proteolytic) Clostridium botulinum type B clusters.

Comparative genomic hybridization analysis of 32 Nordic group I Clostridium botulinum type B strains isolated from various sources revealed two homogeneous clusters, clusters BI and BII. The type B strains differed from reference strain ATCC 3502 by 413 coding sequence (CDS) probes, sharing 88% of all the ATCC 3502 genes represented on the microarray. The two Nordic type B clusters differed from each other by their response to 145 CDS probes related mainly to transport and binding, adaptive mechanisms, fatty acid biosynthesis, the cell membranes, bacteriophages, and transposon-related elements. The most prominent differences between the two clusters were related to resistance to toxic compounds frequently found in the environment, such as arsenic and cadmium, reflecting different adaptive responses in the evolution of the two clusters. Other relatively variable CDS groups were related to surface structures and the gram-positive cell wall, suggesting that the two clusters possess different antigenic properties. All the type B strains carried CDSs putatively related to capsule formation, which may play a role in adaptation to different environmental and clinical niches. Sequencing showed that representative strains of the two type B clusters both carried subtype B2 neurotoxin genes. As many of the type B strains studied have been isolated from foods or associated with botulism, it is expected that the two group I C. botulinum type B clusters present a public health hazard in Nordic countries. Knowing the genetic and physiological markers of these clusters will assist in targeting control measures against these pathogens.

Effects of carbon dioxide on neurotoxin gene expression in nonproteolytic Clostridium botulinum Type E.

Carbon dioxide is an antimicrobial gas commonly used in modified atmosphere packaging. In the present study, the effects of carbon dioxide on the growth of and neurotoxin production by nonproteolytic Clostridium botulinum type E were studied during the growth cycle. Quantitative reverse transcription-PCR and an enzyme-linked immunosorbent assay were used to quantify expression of the type E botulinum neurotoxin gene (cntE) and the formation of type E neurotoxin. The expression levels of cntE were similar in two strains, with relative expression peaking in the transition between exponential phase and stationary phase. In stationary phase, cntE mRNA expression declined rapidly. The cntE mRNA half-life was calculated to be approximately 9 minutes. Neurotoxin formation occurred in late exponential phase and stationary phase. High carbon dioxide concentrations delayed growth by increasing the lag time and decreasing the maximum growth rate. The effects of carbon dioxide concentration on relative neurotoxin gene expression and neurotoxin formation were significant. Expression of cntE mRNA and the formation of extracellular neurotoxin were twofold higher with a headspace carbon dioxide concentration of 70% (vol/vol) compared to 10% (vol/vol). This finding sheds a new, cautionary light on the potential risks of botulism associated with the use of modified atmosphere packaging.

Measurement of humeroradial and humeroulnar transarticular joint forces in the canine elbow joint after humeral wedge and humeral slide osteotomies.

OBJECTIVE: To determine the effect of humeral wedge and humeral slide osteotomies on force distribution between the articular surfaces of the humerus and the radius and ulna in normal canine thoracic limbs. STUDY DESIGN: In vitro mechanical testing. SAMPLE POPULATION: Cadaveric canine right thoracic limbs (n=12). METHODS: Transarticular elbow force maps were measured using a tactile array pressure sensor in elbow joints of axially aligned limbs under 200 N axial load before and after humeral wedge and humeral slide osteotomies. RESULTS: Loading induced 2 distinct areas of high forces that corresponded with the proximal articular surfaces of the radius and ulna. Mean force on the proximal articular surface of the ulna was reduced by 25% and 28% after 4 and 8 mm sliding osteotomies, respectively. Statistically significant differences were not observed for the wedge osteotomies. CONCLUSION: Humeral slide osteotomy significantly decreases force on the proximal articular surface of the ulna. CLINICAL RELEVANCE: The proximal articular surface of the ulna contributes significantly to load transfer through the canine elbow joint. Abnormalities that significantly increase this force might contribute to canine elbow dysplasia, specifically fragmentation of the medial coronoid process and osteochondritis dissecans of the medial aspect of the humeral condyle. Under the conditions studied, the overall reduction in mean joint surface force across the proximal articular surface of the ulna after humeral slide osteotomy indicates that this technique merits further investigation for potential use in medial compartmental osteoarthritis of the canine elbow joint.

Intra-abdominal complications following intestinal anastomoses by suture and staple techniques in dogs.

OBJECTIVE To compare the incidence of intra-abdominal complications in dogs following resection and functional end-to-end stapled anastomosis (FEESA) versus anastomosis with an end-to-end sutured technique for treatment of enteric lesions. DESIGN Multicenter, retrospective descriptive cohort study. ANIMALS 180 dogs. PROCEDURES Medical records of dogs undergoing intestinal resection and anastomosis at 3 nonaffiliated private practice specialty centers were retrospectively reviewed. Preoperative clinical variables, indication for surgery, surgical technique (sutured end-to-end anastomosis vs FEESA), and evidence of postoperative anastomosis site leakage (dehiscence) were recorded. Variables of interest were analyzed for associations with dehiscence. RESULTS Dehiscence rates of sutured and stapled anastomoses were 12 of 93 (13%) and 4 of 87 (5%), respectively; odds of postoperative dehiscence were significantly lower for dogs with FEESAs than for dogs with sutured anastomoses (OR, 0.28; 95% confidence interval, 0.09 to 0.94). Among dogs that underwent surgery for treatment of intestinal dehiscence after surgery at another facility, subsequent dehiscence developed in 3 of 5 with sutured anastomoses and 0 of 11 with stapled anastomoses. Dehiscence rates varied significantly among clinics. No other variable was associated with risk of dehiscence. Eleven of 16 dogs with dehiscence were euthanized without additional surgery. Impaction at the anastomosis site was identified months or years after surgery in 3 dogs (4 anastomosis sites) that had FEESAs. CONCLUSIONS AND CLINICAL RELEVANCE Odds for dehiscence were significantly greater for sutured end-to-end anastomoses than FEESAs, and dogs undergoing surgery for previous dehiscence were significantly more likely to experience a subsequent dehiscence with a sutured anastomosis. However, variability of procedure types and dehiscence rates among clinics suggested further research is needed to confirm these findings. Obstruction at the anastomosis site was identified as a potential long-term complication of FEESA.

Phosphorylation of cyclin D1 at Thr 286 during S phase leads to its proteasomal degradation and allows efficient DNA synthesis.

Continuing proliferation requires regulation of cyclin D1 levels in each cell cycle phase. Growth factors stimulate high levels during G2 phase, which commits the cell to continue through G1 phase with sufficient cyclin D1 to initiate DNA synthesis. Upon entry into S phase, however, cyclin D1 levels rapidly decline. Our goal is to understand the mechanism and importance of this S-phase suppression. Here, we demonstrate that cyclin D1 levels decline during S phase due to reduced protein stability, without alterations in the rate of protein synthesis. This decline depends upon Thr 286, since mutation of this site eliminates the normal pattern of cyclin D1 suppression during S phase. As evidence that phosphorylation of Thr 286 is responsible for this decline, Thr 286 is shown to be more efficiently phosphorylated during S phase than in other cell cycle periods. Finally, high cyclin D1 levels during S phase are shown to inhibit DNA synthesis. This inhibitory activity presumably blocks the growth of cells with altered cyclin D1 expression characteristics. Abnormal stimulation of cyclin D1 might result in levels high enough to promote G1/S phase transition even in the absence of appropriate growth stimuli. In such cells, however, the levels of cyclin D1 would presumably be too high to be suppressed during S phase, resulting in the inhibition of DNA synthesis.

Use of posaconazole in the management of invasive orbital aspergillosis in a cat.

Orbital infection with Aspergillus fumigatus was diagnosed in a Persian cat that was presented with chronic third eyelid protrusion and exophthalmos. Evidence of nasal, sinus, or disseminated aspergillosis was not detected in this cat. Complete surgical excision of diseased tissues was not possible during orbital exenteration, and infection subsequently extended into the tissues of the oral cavity. Oral therapy with itraconazole and parenteral therapy with amphotericin B were ineffective in resolving the infection. Oral therapy with a novel triazole, posaconazole, was curative.

In vitro force mapping of normal canine humeroradial and humeroulnar joints.

OBJECTIVE: To determine the distribution of force between the articular surfaces of the humerus and radius and between the humerus and ulna in normal canine forelimbs. SAMPLE POPULATION: 12 cadaveric canine right forelimbs. PROCEDURE: Transarticular force maps were created by placing a tactile array pressure sensor into the elbow joint cavity and loading cadaveric forelimbs in a materials testing system. Mean joint forces were determined at loads of 50, 100, 150, and 200 N. RESULTS: All tests produced 2 distinct areas of high load that corresponded with the proximal articular surfaces of the radius and ulna. Mean forces for the radial proximal articular surface were slightly but significantly greater than for the ulna, averaging 51% to 52% of total force for all applied loads. CONCLUSIONS AND CLINICAL RELEVANCE: The proximal articular surface of the ulna contributes substantially to load transfer through the canine elbow joint. Abnormalities, which increase this load, might contribute to canine elbow joint dysplasia, specifically fragmentation of the medial coronoid process and osteochondritis dissecans of the medial aspect of the humeral condyle. In the treatment of these conditions, the normal force distribution within the canine elbow joint should be taken into consideration.

Canine Platelet-Rich Plasma Systems: A Prospective Analysis.

OBJECTIVE: To quantitate key parameters of the platelet-rich plasma (PRP) product from five commercial canine PRP systems in healthy, adult canines. MATERIALS AND METHODS: A prospective study was performed from January 2013 to April 2014. Five commercial systems were analyzed using 10 healthy dogs per system.(-) Blood was obtained according to the manufacturer's protocol for each system. The mean baseline whole blood platelet, RBC, WBC, neutrophil, monocyte, and lymphocyte concentrations were determined for each PRP system. All blood samples were processed according to the manufacturer's protocols. The mean PRP product platelet, RBC, WBC, neutrophil, monocyte, and lymphocyte concentrations were determined for each PRP system. These values were then compared to the mean baseline values. Comparisons of mean whole blood and mean PRP product parameters were calculated using a paired t-test with significance established at p = 0.05. RESULTS: Platelet concentration was significantly increased for System 1 (p = 0.0088) and System 3 (p < 0.0001), and was significantly decreased for System 2 (p < 0.0001). All five systems significantly decreased the red blood cell concentration (p < 0.0001 for each system comparison). Neutrophil concentration was significantly decreased for System 2, System 3, and System 4 (p < 0.0001 for each system comparison). Neutrophil concentration was significantly increased for System 5 (p = 0.0089). CLINICAL RELEVANCE: The systems with the highest platelet yield were System 1 and System 3. System 3 increased platelet concentration while significantly reducing the RBC and neutrophil concentrations. Further study is indicated to assess the efficacy of PRP therapy in canines, the efficacy of canine PRP systems, and the clinical applications for PRP therapy in dogs.

Effect of humeral osteotomy on joint surface contact in canine elbow joints.

OBJECTIVE: To determine the effect of sliding and wedge osteotomies of the humerus on the joint surface contact areas in anatomically normal elbow joints of dogs. SAMPLE POPULATION: Left thoracic limbs from 5 skeletally mature mixed-breed canine cadavers. PROCEDURE: Joint casting was performed by placement of colored polymethylmethacrylate in the elbow joint cavity followed by loading in a materials testing system at physiologic angle and load. Joint casting was performed in unaltered specimens, after 10 degrees medial opening wedge osteotomy, and after lateral sliding osteotomy of the proximal portion of the humerus. Computer-aided analysis of photographs of proximal radial and ulnar articular surfaces after each casting procedure was performed. RESULTS: The lateral sliding humeral osteotomy and 10 degrees medial opening wedge osteotomy significantly altered joint surface contact regions of the canine elbow joint. Osteotomies resulted in a reduction in the size of the radial, ulnar, and combined radioulnar contact areas. Both osteotomies also resulted in craniolateral migration of the radial contact area and craniomedial recession of the ulnar contact area. Although the reduction in ulnar contact area with these treatments is consistent with our hypotheses, the reduction in radial contact area was not anticipated. CONCLUSIONS AND CLINICAL RELEVANCE: Humeral osteotomies alter joint surface contact areas of the canine elbow joint in vitro. Humeral osteotomies may decrease contact areas on the diseased region of the joint in dogs with elbow dysplasia; however, the overall decrease in joint surface contact area suggests that these procedures may induce focal increases in pressure that may cause iatrogenic cartilage damage when applied in vivo.

In vitro biomechanical study of rotational stabilizers of the canine elbow joint.

OBJECTIVE: To develop a model for measuring rotary stability of the canine elbow joint and to evaluate the relative contribution of the anconeal process (AN), lateral collateral ligament (LCL), and medial collateral ligament (MCL). SAMPLE POPULATION: 18 forelimbs from 12 canine cadavers. PROCEDURE: Forelimbs were allocated to 3 experimental groups (6 forelimbs/group). Each intact forelimb was placed in extension at an angle of 135 degrees and cycled 50 times from -16 degrees (pronation) to +28 degrees (supination) in a continuous manner at 2.0 Hz. Cycling was repeated following sectioning of the structure of interest (group 1, AN; group 2, LCL; and group 3, MCL). Torque at -12 degrees (pronation) and +18 degrees (supination) was measured for each intact and experimentally sectioned limb. A Student t test was performed to compare torque values obtained from intact verses experimentally sectioned limbs and for comparison with established criteria for differentiation of primary (> or = 33%), secondary (10 to 33%), and tertiary rotational stabilizers (< 10%). RESULTS: In pronation, the AN was the only primary stabilizer (65%). For supination, the LCL was a primary stabilizer (48%), AN was a secondary stabilizer (24%), and MCL was a tertiary stabilizer (7%). CONCLUSIONS AND CLINICAL RELEVANCE: With the elbow joint in extension at an angle of 135 degrees, the AN is a primary rotational stabilizer in pronation, and the LCL is a primary stabilizer in supination. Disruption of the AN or LCL may affect rotary range of motion or compromise stability of the elbow joint in dogs.

Effects of a whole-body spandex garment on rectal temperature and oxygen consumption in healthy dogs.

OBJECTIVE: To determine whether a full-body spandex garment would alter rectal temperatures of healthy dogs at rest in cool and warm environments. DESIGN: Prospective study. ANIMALS: 10 healthy dogs. PROCEDURES: Each dog was evaluated at a low (20 degrees to 25 degrees C [68 degrees to 77 degrees F]) or high (30 degrees to 35 degrees C [86 degrees to 95 degrees F]) ambient temperature while wearing or not wearing a commercially available whole-body spandex garment designed for dogs. Oxygen consumption was measured by placing dogs in a flow-through indirect calorimeter for 90 to 120 minutes. Rectal temperature was measured before dogs were placed in the calorimeter and after they were removed. RESULTS: Rectal temperature increased significantly more at the higher ambient temperature than at the lower temperature and when dogs were not wearing the garment than when they were wearing it. The specific rate of oxygen consumption was significantly higher at the lower ambient temperature than at the higher temperature. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that wearing a snug spandex body garment does not increase the possibility that dogs will overheat while in moderate ambient temperatures. Instead, wearing such a garment may enable dogs to better maintain body temperature during moderate heat loading. These results suggest that such garments might be used for purposes such as wound or suture protection without causing dogs to overheat.

Genome sequence of a proteolytic (Group I) Clostridium botulinum strain Hall A and comparative analysis of the clostridial genomes.

Clostridium botulinum is a heterogeneous Gram-positive species that comprises four genetically and physiologically distinct groups of bacteria that share the ability to produce botulinum neurotoxin, the most poisonous toxin known to man, and the causative agent of botulism, a severe disease of humans and animals. We report here the complete genome sequence of a representative of Group I (proteolytic) C. botulinum (strain Hall A, ATCC 3502). The genome consists of a chromosome (3,886,916 bp) and a plasmid (16,344 bp), which carry 3650 and 19 predicted genes, respectively. Consistent with the proteolytic phenotype of this strain, the genome harbors a large number of genes encoding secreted proteases and enzymes involved in uptake and metabolism of amino acids. The genome also reveals a hitherto unknown ability of C. botulinum to degrade chitin. There is a significant lack of recently acquired DNA, indicating a stable genomic content, in strong contrast to the fluid genome of Clostridium difficile, which can form longer-term relationships with its host. Overall, the genome indicates that C. botulinum is adapted to a saprophytic lifestyle both in soil and aquatic environments. This pathogen relies on its toxin to rapidly kill a wide range of prey species, and to gain access to nutrient sources, it releases a large number of extracellular enzymes to soften and destroy rotting or decayed tissues.

The effect of tibial plateau angle on ground reaction forces 4-17 months after tibial plateau leveling osteotomy in Labrador Retrievers.

OBJECTIVE: To assess the relationship between postoperative tibial plateau angle (TPA) and ground reaction forces (GRFs) in Labrador Retrievers at least 4-months after tibial plateau leveling osteotomy (TPLO) surgery. STUDY DESIGN: A retrospective longitudinal study. ANIMALS: Thirty-two Labrador Retrievers with unilateral cranial cruciate ligament disease that had TPLO and concurrent meniscal surgery. METHODS: TPA and GRFs were measured pre- and > or = 4 months postoperatively. Preoperative GRFs, preoperative TPA, duration of injury, postoperative TPA and degree of rotation were each compared with postoperative GRFs using correlation analysis. Dogs were also grouped by postoperative TPA and compared using 1-way analysis of variance (ANOVA). Postoperative function was compared with meniscal release/meniscectomy, patient age, sex, body weight and follow-up time using ANOVA. RESULTS: No significant relationship was found between preoperative GRFs, preoperative TPA, duration of injury, postoperative TPA, degree of rotation, or meniscal release/meniscectomy and postoperative function. Mean preoperative GRFs for all dogs were 28.8 +/- 9.5 for peak vertical force (PVF) and 9.3 +/- 3.1 for peak vertical impulse (VI). Mean postoperative GRFs for all dogs were 40.4 +/- 5.0 for PVF and 14.1 +/- 1.9 for VI. CONCLUSIONS: No statistically significant relationship was found between postoperative TPA and GRFs after TPLO > or = 4 months after surgery, where the postoperative angle was between 0 and 14 degrees. No significant relationship was found between the preoperative TPA and postoperative function. CLINICAL RELEVANCE: Limb function in Labrador Retrievers was not affected by postoperative TPA and re-operation for cases with a postoperative TPA between 0 and 14 degrees is not recommended.