Effect of signalment on the presentation of canine patients suffering from cranial cruciate ligament disease

Objective : To determine the effect of signalment on the incidence and presentation of patients suffering from cranial cruciate ligament disease. Methods : Data relating to 426 dogs (44 breeds) that met specific selection criteria were obtained from the hospital archive (2002 to 2008). Cases were followed up for 2 years. Results : The breeds most commonly presented with cranial cruciate ligament disease were Labrador retriever (16%), Rottweiler (15%), golden retriever (12%) and boxer (9%). Rottweilers were significantly more likely (69%; P=0·05) to develop and present with (50%; P=0·03) bilateral cranial cruciate ligament disease. Rottweilers presenting with cranial cruciate ligament disease were significantly younger (median 977 days; P<0·0001) than other breeds; golden retrievers being significantly older at presentation (median 1994 days; P=0·004). Neither sex nor neutered status significantly affected the incidence of developing (P=0·77 and P=0·30, respectively) or presenting with (P=0·62 and P=0·35, respectively) bilateral cranial cruciate ligament disease. Entire dogs were significantly younger than neutered dogs at presentation (P=0·0004). Entire female dogs presented significantly younger than neutered females (P=0·0002), entire males (P=0·01) and neutered males (P=0·0001). Clinical Significance : Breed affects the incidence of developing and presenting with bilateral cranial cruciate ligament disease. Breed and sex both affect the age that patients present with cranial cruciate ligament disease.     

Canine dilated cardiomyopathy: a retrospective study of prognostic findings in 367 clinical cases

Objective : To review the association between clinical signs and diagnostic findings and the survival time of dogs with dilated cardiomyopathy (DCM), and any influence of treatment prescribed. Methods : A retrospective observational study of 367 dogs with DCM. Survival times until death or euthanasia for cardiac reasons were analysed using the Kaplan–Meier method plus univariate and multivariate Cox proportional hazards models. Two-tailed P values less than 0·05 were considered statistically significant. Results : In the multivariate model, left ventricular diameter (LVDs)-index (P=0·0067), presence of pulmonary oedema on radio-graphy (P=0·043), presence of ventricular premature complexes (VPCs) (P=0·0012), higher plasma creatinine (P=0·0002), lower plasma protein (P=0·029) and great Dane breed (P=0·0003) were negatively associated with survival. Most dogs were treated with angiotensin-converting enzyme inhibitors (93%) or furosemide (86%), and many received digoxin (50%) and/or pimobendan (30%). Thirteen dogs were lost to follow-up. No conclusions could be made in this study on the association between use of drugs and survival. Clinical Significance : The LVDs-index was the single best variable for assessing the prognosis in this group of dogs with DCM. Other variables that were negatively associated with survival were presence of pulmonary oedema on radiography, presence of VPCs, higher plasma creatinine, lower plasma protein and great Dane breed.     

Lack of correlation between canine heart rate and body size in veterinary clinical practice

Objectives : An association between heart rate (HR) and bodyweight has been reported in dogs and it is common belief that small breeds of dog exhibit higher HR than large breeds. The first aim of this study was to test the null hypothesis that, in veterinary clinical practice, bodyweight does not affect HR measured in healthy dogs. A second objective of this investigation was to assess whether other variables, such as gender, breed morphology, age and demeanour, may have a significant effect on dog’s HR measured in a clinical setting. Methods : The investigation was performed via two different studies: a retrospective analysis performed on 243 electrocardiogram recordings and a prospective study based on 153 standardised clinical examinations. Results : The two separate studies did not show any significant correlation between HR and bodyweight (P=0·5705 and P=0·4682, respectively). Subject’s breed morphology and gender did not appear to affect HR measured under these circumstances. However, dogs under the age of one year seem to have significantly higher HRs than older dogs (P < 0·05). Finally, subject’s demeanour was also found to have a significant influence on HR; lower values were recorded in relaxed dogs, and higher rates were documented in excited, nervous dogs (P < 0·05). Clinical Significance : Normal HR could be erroneously interpreted as bradycardia or tachycardia if bodyweight was to be considered a determinant factor. Instead, HR in healthy dogs undergoing routine clinical examination is related to their demeanour or age, if younger than 12 months, but does not appear to be related to bodyweight.     

The association between the signalment, common causes of canine otitis externa and pathogens

Objective : To determine whether associations exist between pathogens, allergies, conformational abnormalities, endocrinopathies and signalment in canine otitis externa (OE). Methods : Medical records of 149 dogs which met predetermined inclusion criteria were evaluated retrospectively. Correlations between pathogens and the presence of allergy, endocrinopathy, conformational abnormalities and signalment were evaluated statistically. Results : The shar‐pei, German shepherd and cocker spaniel breeds were over‐represented compared with the hospital's breed distribution (P<0·001). German shepherd dogs and cocker spaniels were statistically more prone to infection with rod‐shaped organisms and Labrador retrievers less than other breeds (P=0·034). Almost all dogs that were older than five years when diagnosed with OE had cocci (P=0·01) and also had higher levels of rods (P=0·028). The incidence of rods was higher in endocrinopathies (P=0·004), while that of Malassezia spp. tended to be higher in allergies (P=0·098). There were no statistically significant differences among the groups for all the other parameters examined. Clinical Significance : OE infection is usually not influenced by primary causes or predisposing factors. Endocrinopathies may be followed by a more severe otitis, however. OE may be more severe when it affects older dogs.     

Structural characteristics of the soft palate and meatus nasopharyngeus in brachycephalic and non-brachycephalic dogs analysed by CT

Objectives : The goal of this study was to compare the dimensions of the soft palate and cross‐sectional area of the meatus nasopharyngeus in non‐brachycephalic dogs and brachycephalic dogs with different degrees of severity of brachycephalic airway syndrome using computed tomography. Methods : A total of 26 brachycephalic dogs that had at least one of four major symptoms of snoring, inspiratory effort, stress or exercise intolerance, and syncope were included in this prospective study. The dogs were grouped by the frequency of different clinical signs into absent/minimal brachycephalic airway syndrome and severe brachycephalic airway syndrome groups. Five non‐brachycephalic dogs were studied as control animals. All dogs underwent pharyngeal area computed tomography. Seven measurements were made on the transverse and midsagittal reconstructions. All parameters were compared between controls, absent/minimal and severe brachycephalic airway syndrome groups. Results : The dogs with severe brachycephalic airway syndrome had significantly thicker soft palates compared to absent/minimal brachycephalic airway syndrome (P<0·05) and control (P<0·05) dogs. There were no significant differences among groups with regard to the length of the soft palate or the cross‐sectional area of the airway at the level of the meatus nasopharyngeus. Clinical Relevance : These results support the thickening of the soft palate as a component of severe brachycephalic airway syndrome. Further studies are required to confirm the association between this anatomical characteristic and functional impairment.     

Influence of signalment on developing cranial cruciate rupture in dogs in the UK

Objectives : To investigate risk factors associated with cranial cruciate ligament rupture in dogs. Methods : Retrospective case‐control study: medical records of a first‐opinion veterinary practice were searched for dogs diagnosed with cranial cruciate ligament rupture (1995 to 2007). For each case, six unaffected dogs were randomly selected from all dogs presenting that day for comparison. Multi‐variable binary logistic regression was performed to assess the association of variables on likelihood of cruciate rupture. Results : Frequency of cranial cruciate ligament rupture was 1·19% [95% confidence interval (CI) 1·02 to 1.36%]. West Highland white terriers (n=17), Yorkshire terriers (n=14) and Rottweilers (n=11) were at significantly increased risk of cranial cruciate ligament rupture (P≤0·002). Rottweilers were at five times greater risk compared with other pure breeds (OR 5·12, 95% CI 2·281 to 11·494, P<0·001), obesity quadrupled the risk of cranial cruciate ligament rupture (OR 3·756, 95% CI 1·659 to 8·502, P=0·001) and females were twice as likely to suffer cranial cruciate ligament failure compared to males (OR 2·054, 95% CI 1·467 to 2·877, P<0·001). Dogs less than two years old were statistically less likely to sustain cranial cruciate ligament rupture than dogs older than eight years (OR 0·246, 95% CI 0·127 to 0·477, P<0·001). There was no significant difference in median weights (in kilograms) of neutered dogs, compared to their entire counterparts in either the case group (P=0·994) or in the control group (P=0·630). There was also no significant difference in body condition (‐underweight/normal weight/overweight/obese) of neutered versus entire dogs among the cases (P=0·243), or the controls (P=0·211). Clinical Significance : Cranial cruciate ligament rupture is more likely in Rottweilers and in female dogs, older dogs and obese dogs. Following multi‐variable analysis, it was established that neutering was not associated with increased risk of cranial cruciate ligament rupture.     

Treatment of canine nictitans plasmacytic conjunctivitis with 0–2 per cent cyclosporin ointment

Nictitans plasmacytic conjunctivitis, commonly referred to as plasma cell infiltrate of the nictitans or plasmoma, was diagnosed in 12 dogs (23 eyes) on the basis of clinical signs and nictitans conjunctival biopsy specimens. These dogs underwent a clinical therapeutic trial with twice daily 0·2 per cent cyclosporin ophthalmic ointment. Response to therapy was monitored over a six-week period and repeat biopsy specimens were then taken. Significant (P<0·05) reductions between pre- and post trial scores were recorded for: mucopurulent ocular discharge quantity; degree of bulbar conjunctival hyperaemia; areas of nictitans hyperaemia, thickening and depigmentation. Schirmer tear test values significantly increased between the start and end of treatment. Biopsy specimens were subjected to selective detection procedures for plasma cells (methyl green-pyronin staining) and T lymphocytes (CD3 antigen labelling). Mean cell counts showed a significant reduction in plasma cell numbers, but the trend towards reduced T lymphocyte numbers was not significant.     

Plasma cholesterol and lipoprotein concentrations in the dog: The effects of age, breed, gender and endocrine disease

A combined ultracentrifugation and precipitation technique was used to quantify the plasma lipoprotein concentrations of control dogs (n=33) and dogs with diabetes mellitus (n=11), hyper-adrenocorticism (n=14), hypothyroidism (n=10) and obesity (n=20). In addition, the effect of breed type, age and gender on the lipoprotein phenotype was assessed. Breed type and age were found to have no effect upon cholesterol and lipoprotein concentrations but the high density lipoprotein cholesterol (HDL-C) concentration was greater in intact females than intact males. Cholesterol concentrations were significantly higher than those of the control group in dogs with diabetes mellitus (P<0·01), hyper-adrenocorticism (P<0·01) and hypothyroidism (P<0·001). In dogs with diabetes mellitus this was due to increased concentrations of very low density lipoprotein cholesterol (VLDL-C) (P<0·01) and HDL-C (P<0·05). The concentrations of low density lipoprotein cholesterol (LDL-C) (P<0·05) were significantly increased in dogs with hyperadrenocorticism, while in the hypothyroid dogs, VLDL-C (P<0·05), LDL-C (P<0·001) and HDL-C (P<0·05) were significantly higher than the control group. The cholesterol and lipoprotein concentrations in the obese population were not significantly different from control dogs.     

Hypovitaminosis D in dogs with inflammatory bowel disease and hypoalbuminaemia

Objectives : To compare serum vitamin D metabolites and plasma parathyroid hormone concentrations in dogs with inflammatory bowel disease and normal albumin concentration, dogs with inflammatory bowel disease and hypoalbuminaemia, healthy dogs and hospitalised ill dogs with non‐gastrointestinal illness. Methods : Serum 25 hydroxyvitamin D and 1,25 dihydroxyvitamin D concentrations were measured in 36 healthy dogs, 49 hospitalised ill dogs with non‐gastrointestinal illnesses, 21 dogs with inflammatory bowel disease and normoalbuminaemia and 12 dogs with inflammatory bowel disease and hypoalbuminaemia. Plasma parathyroid hormone and ionised calcium concentrations were measured in a subset of these dogs. Results : Concentrations of serum 25 hydroxyvitamin D were lower in hypoalbuminaemic dogs with inflammatory bowel disease than in the healthy dogs (P<0·001), hospitalised ill dogs (P<0·001) and normoalbuminaemic dogs with inflammatory bowel disease (P<0·001). Dogs with inflammatory bowel disease and hypoalbuminaemia had a higher plasma concentration of parathyroid hormone (P<0·01) and lower plasma concentration of ionised calcium (P<0·001) than hospitalised ill dogs. Dogs with inflammatory bowel disease had a positive correlation between serum 25 hydroxyvitamin D concentrations and serum albumin (P<0·0001), serum calcium (P<0·0001) and plasma ionised calcium (P<0·0005) concentrations. Clinical Significance : Dogs with inflammatory bowel disease and hypoalbuminaemia frequently have ionised hypocalcaemia, high parathyroid hormone and low serum 25 hydroxyvitamin D concentrations. Further studies are indicated to establish the pathogenesis of this disease complication as well as therapeutic strategies to reverse this state.     

Prevalence of adverse food reactions in 130 dogs in Italy with dermatological signs: a retrospective study

Objectives : To determine the prevalence of adverse food reactions (AFRs) in dogs with dermatological signs presented to the referral dermatological clinic of the University of Milan. Methods : The medical records of dogs with dermatological signs were reviewed. Prevalence of AFRs was calculated. Owner and clinician pruritus scores were compared. Breed, sex and age predisposition were statistically tested, as was the association between AFR and selected clinical features. Results : The prevalence of AFRs in dogs with dermatological signs was 12% (16 of 130). AFR was diagnosed in 26% of dogs with allergic disease and 48% of those subjected to a dietary trial. There was a significant association between AFRs and early onset of clinical signs (<1 year) (OR=3·8; P=0·0221, 95% CI=1·27 to 11·16). There was a significant association between AFRs and both otitis externa (OR=5·9; P=0·0015, 95% CI=2 to 17·9) and perianal fistula (OR=26·1; P=0·0058, 95% CI=2·52 to 269·4), although all dogs with perianal fistulas were German shepherd dogs. Clinical Significance : The prevalence of AFRs in the study population was higher than most reported values. Further studies are warranted to investigate the true prevalence of AFR and its possible association with perianal fistula and other potential markers.     

Complications associated with temporary tracheostomy tubes in 42 dogs (1998 to 2007)

Objective : To identify the type and frequency of tracheostomy tube complications, and to determine factors associated with these complications, and with poor outcome. Methods : A database search for dogs undergoing temporary tube tracheostomy was performed. The medical records were scrutinised. The signalment, respiratory disease history, diagnosis, surgery, type and frequency of tube care procedures, type of complications and outcome were recorded. Results : Forty‐two records were found. Complications occurred in 36 of 42 (86%) cases. Bulldogs were more likely to dislodge the tube than other breeds (P=0·0376), and cases with three or more complication types underwent more routine care procedures than those with fewer complications (P=0·0370). Thirty‐four of 42 (81%) dogs had a successfully managed tracheostomy tube and survived until tube removal, or elective euthanasia without significant tube complications. Bulldogs were also significantly (P=0·0376) more likely to have an unsuccessful tube outcome, as were dogs experiencing severe bradycardia during treatment (P=0·0176). Dogs with unsuccessful tube outcome were significantly (P=0·0331) younger than dogs with successful tube outcome. Clinical Significance : Tracheostomy tubes in dogs have a high complication rate but a good outcome in most dogs. Careful management may improve the outcome of dogs with tracheostomy tubes, especially bulldogs and dogs exhibiting bradycardia during treatment.     

Prevention of leptospirosis in young calves by vaccinating their dams in late pregnancy

Idiopathic laryngeal paralysis in dogs is now a frequently recognised disorder, particularly in certain breeds such as the Labrador retriever, Afghan hound and Irish setter. Since it occurs in the older animal, distinguishing the clinical signs and their significance from lower respiratory tract or cardiac disease can be challenging. At present little is known about its aetiology and therefore the treatment is directed at relieving the clinical signs.

Recent work indicates that arytenoid cartilage lateralisation achieves the best results as a method of surgically correcting the laryngeal obstruction. However, it should be remembered that the potential benefits of surgery should be assessed for each individual, taking into account the presence of concurrent disease and lifestyle of the dog.     

X-ray and CT morphology of atlas variants in the dog

To investigate variations in atlas shape in dogs the image archives of the Department for Small Animals and Horses, University of Vienna, and The Royal Veterinary College, University of London were searched for radiographs and CT images of the canine atlas. 32 radiographic and 78 CT studies, including 51 toy and 54 large breed dogs, were retrieved and analysed. Five dogs had both radiographs and CT scans. Patients with pathologic alterations, such as fractures and incomplete ossification of the atlas, as well as oblique projections were excluded. Compared to large breed dogs (body weight more than 30 kg) the atlas of toy breed dogs (body weight less than 10 kg) had a reduced craniocaudal and an increased dorsoventral diameter. The vertebral longitudinal axis appeared to be dorsorotated, resulting in a steeper rise of the atlas wings and a more dorsally located lateral vertebral foramen. When comparing the atlas of toy and large breed dogs, the distribution of three morphologic parameters was statistically different: Ratio length to height (toy breeds > 1, large breeds < or = 1), shape of the vertebral chanal (toy breeds: vertically oval, large breeds: round resp. cross-oval, or vertically oval) and trabecular bone of the dorsal arch (toy breeds: absent, large breeds: present). There was no significant difference in the morphology of the ventral arch. Differences in atlas morphology could contribute to the predisposition of toy breed dogs to atlanto-axial instability; however, further studies are necessary to test this hypothesis.     

Low central venous oxygen saturation is associated with increased mortality in critically ill dogs

Objectives : To investigate relationships between central venous oxygen saturation (ScvO₂) and survival to hospital discharge in dogs. Central venous oxygen saturation is an accessible measure of the balance between systemic oxygen delivery and consumption. Methods : Prospective observational cohort study, enrolling 126 client‐owned dogs with central venous catheters. Central venous oxygen saturation was measured over the 24 hours following intensive care unit admission. Poor outcome was defined as death or euthanasia performed for moribund status. Regression analysis identified independent predictors of non‐survival and physiologic parameters associated with central venous oxygen saturation. Area under the receiver operator curve analysis identified a cut‐off point of central venous oxygen saturation, below which central venous oxygen saturation decrease was associated with increased mortality risk. Results : Mortality risk was 30·9%. Low central venous oxygen saturation was associated with poor outcome (P<0·05). Area under the receiver operator curve analysis selected a central venous oxygen saturation of 68% as the point below which a fall in central venous oxygen saturation was associated with increased mortality risk. For each 10% drop in central venous oxygen saturation below 68%, odds of non‐survival increased by 2·66 times (P=0·0002, 95% confidence interval of odds ratio=1·45 to 4·85). Central venous oxygen saturation was equivalent to lactate in predicting non‐survival. Predictors of central venous oxygen saturation (packed cell volume, mean arterial blood pressure, fever, % arterial haemoglobin saturation as measured by pulse oximeter) were consistent with hypothesised physiologic mechanisms. Clinical Significance : Central venous oxygen saturation was a strong mortality predictor. Further work is needed to determine if therapy targeting central venous oxygen saturation can reduce mortality in canine intensive care unit patients.     

English springer spaniels with significant bradyarrhythmias—presentation,troponin I and follow-up after pacemaker implantation

Objectives : English springer spaniels (ESS) are one of the most frequently presented breeds for pacemaker implantation in the UK and may do so at an early age. In comparison to dogs of other breeds (non-ESS) presenting for pacemaker implantation, cardiac troponin I (cTnI), the outcome and survival of ESS were investigated. Methods : Case records of dogs receiving pacemaker implantation were retrospectively reviewed. Results : Between September 2004 and October 2008, 58 dogs were presented to the Small Animal Teaching Hospital, University of Liverpool for pacemaker implantation. ESS (n=10) was the second most commonly presented breed. ESS were significantly younger than non-ESS (P=0·022). cTnI values were elevated on presentation and a significant reduction was present after pacemaker implantation (P=0·008) in all dogs. No significant difference in initial cTnI was identified comparing ESS and non-ESS (P=0·45) and median survival times were similar (P=0·37). Clinical Significance : ESS may be predisposed to bradyarrhythmias requiring pacemaker implantation. They present at a significantly younger age than non-ESS. Survival times between ESS and non-ESS were similar, despite ESS being paced at a younger age. However, pacemaker implantation is recommended in ESS as median survival times of 30 months with a good quality of life were achieved.     

Neurogenic laryngeal paralysis in the dog

Idiopathic laryngeal paralysis in dogs is now a frequently recognised disorder, particularly in certain breeds such as the Labrador retriever, Afghan hound and Irish setter. Since it occurs in the older animal, distinguishing the clinical signs and their significance from lower respiratory tract or cardiac disease can be challenging. At present little is known about its aetiology and therefore the treatment is directed at relieving the clinical signs. Recent work indicates that arytenoid cartilage lateralisation achieves the best results as a method of surgically correcting the laryngeal obstruction. However, it should be remembered that the potential benefits of surgery should be assessed for each individual, taking into account the presence of concurrent disease and lifestyle of the dog.     

Prognostic significance of specific magnetic resonance imaging features in canine nasal tumours treated by radiotherapy

Objectives : To investigate the prognostic significance of the magnetic resonance (MR) findings of meningeal hyperintensity of the olfactory bulbs and tumour extension into the caudal nasal recess (CNR) in dogs with nasal tumours treated by radiotherapy. Methods : MR images of 41 dogs with nasal tumours treated with radiotherapy were reviewed. The occurrence of neurological signs and survival of patients with and without meningeal hyperintensity of the olfactory bulbs and tumour extension into the CNR were analysed together with possible confounding factors including intracranial extension and patient age. Results : There was no significant association between the presence of meningeal hyperintensity or CNR involvement and the occurrence of neurological signs. Although there was a tendency towards shorter survival in dogs with tumour extension into the CNR, multivariable analysis showed no significant difference in survival between dogs with/without CNR involvement, meningeal hyperintensity or intracranial tumour extension (P=0·12, 0·50 and 0·57, respectively). Clinical Significance : In dogs with nasal tumours treated with radiotherapy, tumour extension into the cranium is not necessarily associated with shorter survival in patients without neurological signs at time of diagnosis. Although a definite influence of CNR involvement on case outcome could not be demonstrated, studies with a larger population are warranted.     

Surgical treatment of severe pulmonic stenosis under cardiopulmonary bypass in small dogs

Objectives : The aim of this study was to report the long‐term outcome of the surgical palliation of pulmonic stenosis in dogs. Methods : The subjects comprised three female and six male dogs, mean (±sd) age: 23 (±25) months, mean (±sd) weight: 3·4 (±2·1) kg, diagnosed with severe pulmonic stenosis and right ventricular hypertrophy, with an average preoperative pressure gradient of 153 (±43) mmHg on echocardiography. Results : The pressure overload with severe pulmonic stenosis was reduced by valvotomy, i.e., open pulmonary valve commissurotomy, with/without biomembrane patch grafting, under cardiopulmonary bypass. The postoperative pressure gradient at 1 to 7 days was significantly decreased to 65 (±39) mmHg (P<0·05). The reduced pressure gradient was maintained at 58 (±38) mmHg at final follow‐up. Clinical Significance : Open valvotomy, pulmonary valve commissurotomy and biomembrane patch grafting were effective in reducing obstruction in severe pulmonic stenosis in dogs.     

Initial evaluation of canine urinary cystatin C as a marker of renal tubular function

Objectives : To evaluate the performance of a particle‐enhanced turbidimetric assay for measuring canine urinary cystatin C and to investigate if the urinary cystatin C to creatinine ratio is higher in dogs with renal disease than in non‐renal disease dogs. Methods : Urinary cystatin C was measured by particle‐enhanced turbidimetric assay using an avian antihuman cystatin C antibody and the performance of this assay was evaluated. Clinical relevance was tested in 46 dogs that were divided into three groups: healthy dogs (n=14), non‐renal disease dogs (n=17) and dogs with renal disease (n=15). Results : The assay was linear (R2=0·99) and precise (mean intra‐ and inter‐assay coefficients of variation were 2·3 and 2·9%, respectively). The recovery was 111·5% and the limit of blank was 0·02 mg/L. Urinary cystatin C and urinary cystatin C to creatinine ratio differed significantly (P<0·001) between the three cohorts of dogs. Clinical Significance : Measurement of cystatin C by particle‐enhanced turbidimetric assay performed with high precision and linearity. This assay can be processed on automated clinical chemistry analysers making it widely available to commercial laboratories. Urinary cystatin C to creatinine ratio can differentiate dogs with renal disease from dogs without renal disease. These preliminary results suggest that urinary cystatin C to creatinine ratio is a promising marker for evaluating renal tubular function.