Symmetrical onychomadesis in Norwegian Gordon and English setters

This study reports the condition onychomadesis affecting multiple claws in Norwegian Gordon and English setters. Medical records of and claw biopsies from 18 Gordon and four English setters with onychomadesis of multiple claws were obtained from July 2005 to January 2007. Only dogs with symmetrical onychomadesis and no signs of concurrent disease were included. Histopathological features varied between dogs, but typically included interface dermatitis with subepidermal cleft formation, pigment incontinence, basal cell vacuolization and necrosis, spongiosis and lymphocytic exocytosis, a lymphocytic, plasmacytic subepidermal inflammation, and fibroplasia. In two dogs, histopathological signs of a superficial infection were present. The age of onset of disease varied between 2 and 7 years with a mean of 3.9 years, and was not correlated with vaccination time. Six of the affected dogs also had siblings with the disease. Due to the close relationship of the affected dogs, pedigree map analysis was not possible. Three dogs were euthanized because of the disease and two had regrowth of normal claws. Seventeen dogs had persistent onychodystrophy that typically was nonpainful during therapy which in most dogs consisted of fatty acid supplementation or prednisolone.     

Antinuclear antibodies (ANA) in Gordon setters with symmetrical lupoid onychodystrophy and black hair follicular dysplasia

Antinuclear antibodies (ANA) were demonstrated in 3 out of 10 Gordon setters with symmetrical lupoid onychodystrophy and in 5 out of 13 Gordon setters with black hair follicular dysplasia. Two dogs showed both symmetrical lupoid onychodystrophy and black hair follicular dysplasia, and one of these was ANA positive. The results suggest that symmetrical lupoid onychodystrophy and black hair follicular dysplasia in the Gordon setter might be autoimmune diseases that are pathogenetically related, which might indicate a common genetic predisposition.     

Effect of acetazolamide and subsequent ventriculo-peritoneal shunting on clinical signs and ventricular volumes in dogs with internal hydrocephalus

Background

Acetazolamide is recommended for the reduction of cerebrospinal fluid production in canine internal hydrocephalus. The efficacy of the drug in terms of alleviation of the clinical symptoms and the restoration of normal ventricular volume has not been documented. We hypothesize that acetazolamide inadequately improve clinical signs and has no effect on the ventricular volume. Six dogs with internal hydrocephalus underwent neurological examination and were examined by magnetic resonance imaging, on the day of the diagnosis, after treatment with acetazolamide directly before surgery, and 6 weeks after implantation of a vetriculo-peritoneal shunt due to lack of improvement after medical therapy with 10 mg/kg acetazolamide three times daily (TID). The ventricular volume in relation to the total brain volume was determined on each occasion. The changes in relative ventricular volume and of the neurological status were assessed and compared.

Results

McNemar’s test revealed no significant differences in clinical symptoms before and after medical treatment (P > 0.05). However, clinical symptoms changed significantly after surgical treatment (P = 0.001). The ventricle-brain ratio was not significantly changed after therapy with acetazolamide (P > 0.05); however, after subsequent shunt implantation, it was significantly reduced (P = 0.001).

Conclusion

Acetazolamide (10 mg/kg TID) showed no effects on clinical signs or ventricular volume in dogs with internal hydrocephalus. After subsequent ventriculo-peritoneal shunting, the dogs had a significantly reduced cerebral ventricular volume and five out of six dogs had no abnormal findings in neurological examination.     

A scavenging double mask to reduce workplace contamination during mask induction of inhalation anesthesia in dogs

Background

Workplace contamination by the use of volatile anesthetic agents should be kept to a minimum if a potential health hazard is to be minimised. Mask induction of animals is a common procedure. The present study investigates the efficiency of a novel scavenging double mask in reducing waste gas concentrations in the breathing zone of the anesthetist performing this procedure.

Methods

Twelve beagle dogs (ASA I) undergoing general anesthesia for a dental procedure were intravenously premedicated with medetomidine and butorphanol (10 μg/kg and 0.2 mg/kg). Anesthesia was induced via a custom-made scavenging mask using isoflurane in oxygen. In six dogs (group S), scavenging from the mask was performed whereas in six other dogs (group NS) the scavenging function was disabled. Isoflurane concentration was continuously measured with photoacoustic spectroscopy at the level of the shoulder of the anesthetist before and during mask induction and additionally during intubation. Statistical analysis was performed with a Student t- test and a Mann-Whitney U test (p < 0.05 for significance).

Results

The mean isoflurane concentration during baseline (premedication) was 1.8 ± 0.8 ppm and 2.3 ± 0.6 ppm in group S and NS respectively. This increased during mask induction to 2.0 ± 0.8 ppm and 11.2 ± 6.0 ppm respectively (p < 0.01). The maximum isoflurane concentration ranged from 0.7 ppm to 2.8 ppm and from from 8.3 ppm to 43.7 ppm in group S and NS respectively.

Conclusion

This double mask can be used to induce inhalation anesthesia in dogs. Scavenging from the mask significantly decreases the amount of waste anaesthetic gas concentrations in the breathing zone of the anesthetist. Therefore, such a system can be recommended whenever induction or maintenance of general anesthesia by mask is considered.     

Efficacy of two low-dose oral tylosin regimens in controlling the relapse of diarrhea in dogs with tylosin-responsive diarrhea: a prospective,single-blinded,two-arm parallel,clinical field trial

Background

Despite its wide acceptance as a treatment for canine chronic enteropathies, the macrolide antibiotic tylosin lacks official oral dosage recommendations. Not even textbooks share consensus about the dose; daily recommendations vary from 25 to 80 mg/kg and dosing intervals from one to three times daily.The objective of this prospective, single-blinded, two-arm parallel, clinical field trial was to determine whether doses of 5 mg/kg or 15 mg/kg tylosin administered orally once daily for seven days would have a similar effect on fecal consistency in diarrhea relapses to that of a 25 mg/kg dose of tylosin administered once daily for seven days, a dosage that has proved effective in controlling canine tylosin-responsive diarrhea (TRD). A further objective was to compare the efficacy of the 5 mg/kg and 15 mg/kg tylosin dosages. Fifteen client-owned dogs diagnosed with TRD that had responded to a dose of 25 mg/kg tylosin once daily for seven days were enrolled in the study. After a relapse of diarrhea the dogs were allocated into two groups receiving tylosin orally in doses of either 5 mg/kg or 15 mg/kg once daily for seven days. The owners were blinded to the dosage. The elimination of diarrhea was the main criterion in assessing treatment success. The mean fecal consistency score of the last three treatment days for all dosages, including 25 mg/kg, as evaluated by the owners according to a standardized fecal scoring system, served as the primary outcome measures.

Results

All eight dogs responded to the 5 mg/kg dose, and six of seven dogs responded to the 15 mg/kg dose. The mean fecal consistency scores at the 25 mg/kg tylosin dosage were no significantly different from scores at the 5 mg/kg or 15 mg/kg tylosin dosages (P = 0.672, P = 0.345).

Conclusions

Interestingly, 14/15 (93%) of the dogs responding to a dose of 25 mg/kg tylosin once daily for seven days also responded to the lower dosages at diarrhea relapse. The data indicate that a suitable dose of tylosin for treating diarrhea relapse in canine TRD could be as low as 5 mg/kg once daily for seven days.     

Speckle tracking echocardiography in mature Irish Wolfhound dogs: technical feasibility,measurement error and reference intervals

Background

Two-dimensional strain measurements obtained by speckle tracking echocardiography (STE) have been reported in both humans and dogs. Incorporation of this technique into canine clinical practice requires the availability of measurements from clinically normal dogs, ideally of the same breed, taken under normal clinical conditions.The aims of this prospective study were to assess if it is possible to obtain STE data during a routine echocardiographic examination in Irish Wolfhound dogs and that these data will provide reference values and an estimation of measurement error.

Methods

Fifty- four healthy mature Irish Wolfhounds were used. These were scanned under normal clinical conditions to obtain in one session both standard echocardiographic parameters and STE data. Measurement error was determined separately in 5 healthy mature Irish Wolfhounds.

Results

Eight dogs were rejected by the software algorithm for reasons of image quality, resulting in a total of 46 dogs (85.2%) being included in the statistical analysis. In 46 dogs it was possible to obtain STE data from three scanning planes, as well as to measure the rotation of the left ventricle at two levels and thus calculate the torsion of the heart. The mean peak radial strain at the cardiac apex (RS-apex) was 45.1 ± 10.4% (n = 44), and the mean peak radial strain at the base (RS-base) was 36.9 ± 14.7% (n = 46). The mean peak circumferential strain at the apex (CS-apex) was -24.8 ± 6.2% (n = 44), and the mean peak circumferential strain at the heart base (CS-base) was -15.9 ± 3.2% (n = 44). The mean peak longitudinal strain (LS) was -16.2 ± 3.0% (n = 46). The calculated mean peak torsion of the heart was 11.6 ± 5.1 degrees (n = 45).The measurement error was 24.8%, 26.4%, 11.5%, 6.7%, 9.0% and 10 degrees, for RS-apex, RS-base, CS-apex, CS-base, LS and torsion, respectively.

Conclusions

It is concluded that this technique can be included in a normal echocardiographic examination in large breed dogs under clinical conditions. The usefulness of the reference values reported here, given their wide normal range, will ultimately be determined by the values that are obtained from a large numbers of diseased dogs.     

Toxicokinetics of mercury in blood compartments and hair of fish-fed sled dogs

Background

Understanding mercury (Hg) distribution in blood and the importance of hair as an excretory pathway is critical for evaluating risk from long term dietary Hg exposure. The major objective of this study was to characterize changes in total Hg concentrations in specific blood compartments and hair over time due to long term piscivory.

Methods

Eight sled dogs (Canis lupus familiaris) were fed either a fish and kibble diet (n = 4), or a fish-free control diet (n = 4) for 12 weeks. Concentrations of Hg were monitored throughout the exposure period, and for 10 weeks post exposure, until Hg concentrations in all blood compartments of one of the exposed dogs dropped below detection limit. Additionally, foreleg hair was sampled during acclimation and weeks 0 and 12.

Results

Hg was detected primarily in whole blood and packed cells, although it was sporadically detected at low concentrations in plasma and serum in two of the fish fed dogs. Dogs ingested an estimated average of 13.4 ± 0.58 μg Hg per kg body weight per day. Hg was detectable in whole blood and packed cells within a week of exposure. Detected concentrations continued to rise until plateauing at approximately 3-6 weeks of exposure at a mean of 9.2 ± 1.97 ng/g (ppb) in whole blood. Hg concentration decreased post exposure following 1st order elimination. The mean half-life (t_1/2) in whole blood for Hg was 7 weeks. Mean Hg in hair for the fish-fed dogs at week 12 was 540 ± 111 ppb and was significantly greater (about 7-fold) than the Hg hair concentration for the control dogs. The hair to blood ratio for Hg in fish-fed dogs was 59.0 ± 7.6:1.

Conclusions

This study found the sled dog model to be an effective method for investigating and characterizing blood Hg distribution (whole blood, serum, plasma, packed cells) and toxicokinetics associated with a piscivorous diet, especially for Hg-exposed fur bearing mammals (such as polar bears). Although hair excretion and hair to blood Hg ratios were not similar to human concentrations and ratios, the sled dog toxicokinetics of Hg in blood, was more similar to that of humans than traditional laboratory animals (such as the rat).     

Prevalence of thermophilic Campylobacter species in Swedish dogs and characterization of C. jejuni isolates

Background

The aims of this study were to investigate the prevalence of Campylobacter species in Swedish dogs, to identify the species of the Campylobacter isolates and to genotype the C. jejuni isolates. Young and healthy dogs were targeted and the sampling was performed at 11 veterinary clinics throughout Sweden from October 2011 to October 2012. Faecal swab samples were collected and sent to the laboratory at the National Veterinary Institute (SVA) for isolation of Campylobacter, speciation and genotyping.

Results

Campylobacter spp. were isolated from 67 of the 180 sampled dogs which yields an overall prevalence of 37%. The most prevalent species of Campylobacter among the participating dogs was C. upsaliensis with 52 of the 67 identified isolates. A lower prevalence was observed for C. jejuni with seven identified isolates and one isolate was identified as C. helveticus. Multi-locus sequence typing (MLST) was carried out on the seven C. jejuni isolates and all sequence types that were found are also commonly found in humans. The dogs were divided into three age groups; 1) under 12 months, 2) 12 to 23 months and 3) 24 months and older. The highest prevalence was found in the two younger age groups. Dogs shedding C. jejuni were between 3–12 months of age while dogs shedding C. upsaliensis were found in all ages.

Conclusions

The present investigation finds that Campylobacter spp. known to cause campylobacteriosis in humans are present in Swedish dogs. The results suggest an age predisposition where dogs under 2 years of age are more likely to shed Campylobacter spp. than older dogs. The most commonly isolated species was C. upsaliensis followed by C. jejuni, which was only detected in dogs up to 12 months of age. All C. jejuni isolates identified in the present study were of the same MLST types that have previously been described both in humans and in animals. The awareness of the Campylobacter risk of healthy young dogs may be an important way to reduce the transmission from dogs to infants, young children and immunocompromised adults.     

Clostridium difficile in faeces from healthy dogs and dogs with diarrhea

Background

This study was conducted to evaluate the faecal occurrence and characterization of Clostridium difficile in clinically healthy dogs (N = 50) and in dogs with diarrhea (N = 20) in the Stockholm-Uppsala region of Sweden.

Findings

Clostridium difficile was isolated from 2/50 healthy dogs and from 2/20 diarrheic dogs. Isolates from healthy dogs were negative for toxin A and B and for the tcdA and tcdB genes. Both isolates from diarrheic dogs were positive for toxin B and for the tcdA and tcdB genes. The C. difficile isolates from healthy dogs had PCR ribotype 009 (SE-type 6) and 010 (SE-type 3) whereas both isolates from dogs with diarrhoea had the toxigenic ribotype 014 (SE-type 21). One of the isolates from healthy dogs was initially resistant to metronidazole.

Conclusions

This study revealed presence of toxigenic C. difficile in faecal samples of diarrheic dogs and low number of non- toxigenic isolates in healthy dogs from Uppsala-Stockholm region in Sweden. However, more comprehensive studies are warranted to investigate the role of C. difficile in gastrointestinal disease in dogs.     

Plasma and Urine Neutrophil Gelatinase–Associated Lipocalin (NGAL) in Dogs with Acute Kidney Injury or Chronic Kidney Disease

Background

Neutrophil gelatinase–associated lipocalin (NGAL) is a protein that is used in human medicine as a real‐time indicator of acute kidney injury (AKI).

Hypothesis

Dogs with AKI have significantly higher plasma NGAL concentration and urine NGAL‐to‐creatinine ratio (UNCR) compared with healthy dogs and dogs with chronic kidney disease (CKD).

Animals

18 healthy control dogs, 17 dogs with CKD, and 48 dogs with AKI.

Methods

Over a period of 1 year, all dogs with renal azotemia were prospectively included. Urine and plasma samples were collected during the first 24 hours after presentation or after development of renal azotemia. Plasma and urine NGAL concentrations were measured with a commercially available canine NGAL Elisa Kit (Bioporto® Diagnostic) and UNCR was calculated. A single‐injection plasma inulin clearance was performed in the healthy dogs.

Results

Median (range) NGAL plasma concentration in healthy dogs, dogs with CKD, and AKI were 10.7 ng/mL (2.5–21.2), 22.0 ng/mL (7.7–62.3), and 48.3 ng/mL (5.7–469.0), respectively. UNCR was 2 × 10⁻⁸ (0–46), 1,424 × 10⁻⁸ (385–18,347), and 2,366 × 10⁻⁸ (36–994,669), respectively. Dogs with renal azotemia had significantly higher NGAL concentrations and UNCR than did healthy dogs (P < .0001 for both). Plasma NGAL concentration was significantly higher in dogs with AKI compared with dogs with CKD (P = .027).

Conclusions and Clinical Importance

Plasma NGAL could be helpful to differentiate AKI from CKD in dogs with renal azotemia.     

Treatment of canine generalized demodicosis associated with hyperadrenocorticism with spot-on moxidectin and imidacloprid

Background

Canine generalized demodicosis associated with hyperadrenocorticism is often problematic and might be intractable. The aim of this study was to report the efficacy of a weekly application of spot-on moxidectin/imidacloprid in dogs with hyperadrenocorticism and secondary generalized demodicosis.

Methods

Dogs with hyperadrenocorticism and secondary generalized demodicosis were included. The condition of hyperadrenocorticism was treated and stabilized with trilostane before and throughout the study period in all dogs.

Results

Average total live adult mite counts before treatment and after four, eight and 12 weeks of spot-on moxidectin/imidacloprid (2.5/10 mg/kg) applications were 20.1 ± 6.3 (range, 13–33), 0.5 ± 0.7 (range, 0–2; 6/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative) and 0.1 ± 0.3 (range, 0–1; 10/11 were negative) respectively; this difference was significant (P < 0.001). Ten of 11 dogs (90.1%) achieved clinical remission, as demonstrated by the absence of demodectic mites at any life stage at monthly scrapings for eight consecutive weeks, and maintained remission throughout the 12-month follow-up period.

Conclusion

The weekly application of spot-on moxidectin/imidacloprid appeared to be effective and safe against generalized adult onset canine demodicosis associated with hyperadrenocorticism.     

Evaluation of adverse reactions in dogs following intravenous mesenchymal stem cell transplantation

Background

Recent studies have assessed the therapeutic potential and drawbacks of mesenchymal stem cells (MSCs). The adverse reactions of intravenous transplantation of bone marrow (BM)-derived MSCs were examined at varying doses and frequencies of administration.Nine healthy beagle dogs were purchased from a commercial laboratory. The dogs were distributed equally (n = 3 per group) and randomly into three groups. All dogs received allogeneic BM-derived MSCs: 2 × 10⁶ once (group A), 2 × 10⁷ once (group B), and 2 × 10⁶ for three consecutive days (group C). Various laboratory examinations, multi-detector computed tomography features and histopathology were evaluated to clarify the clinical and diagnostic features of adverse reactions of MSCs administration, prior to receiving MSCs (pre procedure) and on days 1, 3, and 7 post transplantation.

Results

Only one dog had clinical signs during and after MSCs transplantation. Dogs receiving 2 × 10⁶ MSCs showed increased numbers of lymphocytes but the total white blood cell counts were not elevated (P < 0.01). Multi-detector computed tomography (MDCT) revealed pulmonary parenchymal changes in one dog and histopathologic examination revealed pulmonary parenchymal edema and hemorrhage in four dogs. The presence of pulmonary thromboembolism was not detected in either examination.

Conclusions

We considered the presence of pulmonary edema and hemorrhage as possible adverse reactions after intravenous MSCs transplantation; however these results should be cautiously interpreted.     

Evaluation of total oxidant and antioxidant status in dogs under different CO2 pneumoperitoneum conditions

Background

The induction of the pneumoperitoneum increases intraabdominal pressure (IAP), causing splanchnic ischemia, whereas its deflation normalizes IAP and splanchnic blood flow. We investigated the oxidant-antioxidant status of dogs who underwent low pressure (7 mm Hg), standard pressure (12 mm Hg), and high pressure (15 mm Hg) pneumoperitoneum.

Results

Twenty-four beagle dogs (12 males and 12 females), 4–6 years old, weighing 8–11 kg were used. The animals were assigned to one of four groups (n = 6 dogs). Group 1 served as a control; these animals received only anaesthesia for 90 min. In groups 2, 3 and 4, intra-abdominal pressure was increased to 7, 12 and 15 mmHg, respectively, and maintained for 60 min. Total oxidant status (TOS) and total antioxidant status (TAS) were determined in venous blood samples. The percentage ratio of TOS to TAS provided an oxidative stress index (OSI).No significant difference in TOS levels was found among the groups. A significant decrease in TAS levels and an increase in OSI levels were observed at 90 min and 24 h of pneumoperitoneum deflation within group 4. No differences were found among the groups.

Conclusions

A high pressure pneumoperitoneum induced significant changes in TAS and OSI. In addition, TOS and TAS levels are useful markers for evaluating changes in the oxidative status caused by a pneumoperitoneum during laparoscopy. Furthermore, a low-pressure pneumoperitoneum could attenuate oxidative stress induced by CO₂ insufflation in dogs.     

Epidemiology of methicillin resistant Staphylococcus pseudintermedius in guide dogs in Finland

Background

Methicillin resistant Staphylococcus pseudintermedius (MRSP) and Staphylococcus aureus (MRSA) are common multi-drug resistant (MDR) bacteria in dogs. In 2012–2013 three dogs of the Guide Dog School of the Finnish Federation of the Visually Impaired were found to be MRSP positive. Guide dogs have regular contact with each other during their first year of life and prolonged contact when in training. Since dogs are placed in different parts of Finland after training, there is a risk for national spread of MDR bacteria. In this study the prevalence of MRSP and MRSA, as well as the risk factors for MRSP were determined in the Finnish guide dog population. MRSP isolates were investigated using molecular methods and compared to the earlier isolates.

Results

Out of 132 tested dogs 4 were MRSP positive thus giving the prevalence estimate of 3% (95% CI: 1–8%) for MRSP in the target population. MRSA was not detected (prevalence estimate 0%, 95% CI: 0–3%). Risk factors associated with MRSP were being a breeding bitch (OR = 8.4; 95% CI: 1.1–64.1, P = 0.012), the number of veterinary visits (OR = 1.23; 95% CI: 1.0–1.5, P = 0.025) and number of antimicrobial courses (OR = 1.63; 95% CI: 1.0–2.55; P = 0.035). Identified MRSP isolates belonged to five different sequence types (ST45, 71, 402, 403 and 404). All ST71 isolates carried SCCmec II-III, while the SCCmec type of the ST45 and ST402 (a single locus variant of ST45) isolates were non-typeable with the method used.

Conclusions

MRSP and MRSA had low prevalence in the studied dog population despite the close contact between dogs, and the MRSP population was heterogenic. Antimicrobial therapy and veterinary visits are risk factors for MRSP even among a small case group.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-015-0129-8) contains supplementary material, which is available to authorized users.     

Serum Adipokine Concentrations in Dogs with Naturally Occurring Pituitary‐Dependent Hyperadrenocorticism

Background

An excess of intra‐abdominal fat is observed frequently in dogs with hyperadrenocorticism (HAC). Adipokine dysregulation is a possible cause of complications related to visceral obesity, but little information is available on adipokine in dogs with naturally occurring HAC.

Objectives

To examine the differences in the circulating adipokines concentrations in overweight dogs with and without pituitary‐dependent HAC (PDH).

Animals

Thirty healthy dogs and 15 client‐owned dogs with PDH.

Methods

Case–controlled observational study, which enrolled 15 overweight dogs diagnosed with PDH and 30 otherwise healthy dogs of similar body condition score. Nine of 15 dogs with PDH were treated with low‐dose trilostane twice daily and reassessed after treatment.

Results

The serum leptin (P < .0001) and insulin (P < .0001) concentrations were significantly higher in the PDH group (leptin, 22.8 ± 8.8 [mean ± SD]; insulin, 9.1 ± 6.1) than the healthy group (leptin, 4.9 ± 3.7; insulin, 1.9 ± 0.9). However, there were no significant differences in the adiponectin, resistin, tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐6, IL‐10, and IL‐18 levels between the 2 groups. In the PDH group, the serum cortisol concentrations had a linear association with the leptin concentrations, and there were significant decreases in the leptin (P = .0039) and insulin (P = .0039) levels after trilostane treatment. However, the leptin and insulin levels remained higher after trilostane treatment than in healthy control dogs with similar body condition score.

Conclusions and Clinical Importance

Hypercortisolemia in dogs with PDH might upregulate the circulating leptin levels. However, a large population‐based study will be necessary to determine whether the upregulation of leptin is involved directly with the complications caused by HAC.     

Effect of Trilostane and Mitotane on Aldosterone Secretory Reserve in Dogs with Pituitary‐Dependent Hyperadrenocorticism

Background

Maximal aldosterone secretion in healthy dogs occurs 30 minutes postadrenocorticotropin (ACTH; 5 μg/kg IV) stimulation. The effect of trilostane and mitotane on aldosterone at that time is unknown.

Objectives

To assess the effect of trilostane and mitotane in dogs with pituitary‐dependent hyperadrenocorticism on aldosterone secretory reserve. To determine if aldosterone concentration correlates with electrolyte concentrations.

Animals

Serum collected from 79 client‐owned dogs and 33 stored samples.

Methods

Client‐owned dogs had ACTH stimulation tests with cortisol concentrations measured at 0 and 60 minutes and aldosterone concentrations measured at 0, 30, and 60 minutes. Stored samples had aldosterone concentrations measured at 0 and 60 minutes. Ten historical clinically healthy controls were included. All had basal sodium and potassium concentrations measured.

Results

The aldosterone concentrations in the mitotane‐ and trilostane‐treated dogs at 30 and 60 minutes post‐ACTH were significantly lower than in clinically healthy dogs; no significant difference was detected in aldosterone concentration between 30 and 60 minutes in treated dogs. However, a significantly higher percentage of dogs had decreased aldosterone secretory reserve detected at 30 minutes than at 60 minutes. At 30 minutes, decreased secretory reserve was detected in 49% and 78% of trilostane‐ and mitotane‐treated dogs, respectively. No correlation was detected between aldosterone and serum electrolyte concentrations.

Conclusions and Clinical Importance

Decreased aldosterone secretory reserve is common in trilostane‐ and mitotane‐treated dogs; it cannot be predicted by measurement of serum electrolyte concentrations. Aldosterone concentration at 30 minutes post‐ACTH stimulation identifies more dogs with decreased aldosterone secretory reserve than conventional testing at 60 minutes.     

Pharmacokinetics of Total Thyroxine after Repeated Oral Administration of Levothyroxine Solution and its Clinical Efficacy in Hypothyroid Dogs

Background

Oral levothyroxine (l‐T₄) supplementation is commonly used to treat hypothyroid dogs.

Objectives

Investigate the plasma profile and pharmacokinetics of total thyroxine (tT₄) after PO administration of a l‐T₄ solution and its clinical efficacy in hypothyroid dogs.

Animals

Ten dogs with naturally occurring hypothyroidism.

Methods

After hypothyroidism diagnosis and supplementation with l‐T₄ solution PO q24h at 20 μg/kg BW for minimum 4 weeks, the plasma profile and pharmacokinetics of tT₄ were determined over 34 hours and the clinical condition of the dogs was evaluated.

Results

Before dosing for pharmacokinetic evaluation, mean tT₄ concentration was 23 ± 9 nmol/L. l‐T₄ was absorbed rapidly (t _max, 5 hours), reaching a mean maximal tT₄ concentration of 56 ± 11 nmol/L. The apparent terminal half‐life was 11.8 hours. Clinical signs of hypothyroidism improved or resolved in all dogs after 4 weeks of treatment. The dosage of 20 μg/kg PO q24h was judged appropriate in 5 dogs, and 4 dogs required slight increases (9–16%). Twice daily treatment, with a 30% increase in dosage, was necessary for 1 dog.

Conclusions and Clinical Importance

The pharmacokinetics of l‐T₄ in hypothyroid dogs was similar to that reported in healthy euthyroid dogs. Clinical and hormonal responses to l‐T₄ solution were rapid in all dogs. The starting dosage of 20 μg/kg PO q24h was suitable for maintenance supplementation in 50% of the dogs, minor dosage modification was required in 4 other dogs, and treatment q12h was required in 1 dog.     

Original surgical treatment of thoracolumbar subarachnoid cysts in six chondrodystrophic dogs

Background

Subarachnoid cysts are rare conditions in veterinary medicine, associated with spinal cord dysfunction. Most of the 100 cases of subarachnoid cysts described since the first report in 1968 were apparently not true cysts. Reported cysts are usually situated in the cervical area and occur in predisposed breeds such as the Rottweiler. The purpose of this retrospective study, from May 2003 to April 2012, was to describe the distinctive features of thoracolumbar spinal subarachnoid cysts, together with their surgical treatment and outcome in 6 chondrodystrophic dogs.

Results

Five Pugs and 1 French Bulldog were examined. Images suggestive of a subarachnoid cyst were obtained by myelography (2/6) and computed tomography myelography (4/6), and associated disc herniation was observed in 3/6 dogs. A hemilaminectomy was performed. The protruding disc eventually found in 5/6 dogs was treated by lateral corpectomy. The ventral leptomeningeal adhesions observed in all dogs after durotomy were dissected. No or only mild post-operative neurological degradation was observed. Follow-up studies (7 months to 4 years) indicated good outcome and no recurrence.

Conclusions

All the thoracolumbar subarachnoid cysts described in these 6 chondrodystrophic dogs were associated with leptomeningeal adhesions. Good results seemed to be obtained by dissecting and removing these adhesions. A protruding disc, found here in 5/6 dogs, needs to be ruled out and can be treated by lateral corpectomy.     

Associations among systemic blood pressure,microalbuminuria and albuminuria in dogs affected with pituitary- and adrenal-dependent hyperadrenocorticism

Background

Hypertension and proteinuria are medical complications associated with the multisystemic effects of long-term hypercortisolism in dogs with hyperadrenocorticism (HAC).

Methods

This study investigated the relationships among adrenocorticotropic hormone (ACTH)-stimulation test results, systemic blood pressure, and microalbuminuria in clinically-healthy dogs (n = 100), in dogs affected with naturally occurring pituitary-dependent (PDH; n = 40), or adrenal-dependent hyperadrenocorticism (ADH; n = 30).

Results

Mean systemic blood pressure was similar between clinically healthy dogs and dogs with HAC (p = 0.803). However the incidence of hypertension was highest in dogs with ADH (p = 0.017), followed by dogs with PDH, with the lowest levels in clinically healthy dogs (p = 0.019). Presence of microalbuminuria and albuminuria in clinically healthy dogs and dogs affected with HAC was significantly different (p < 0.001); incidences of albuminuria followed the same pattern of hypertension; highest incidence in dogs with ADH, and lowest level in clinically healthy dogs; but microalbuminuria showed a different pattern: clinically healthy dogs had highest incidences and dogs with ADH had lowest incidence. The presence of albuminuria was not associated with blood pressure values, regardless of whether dogs were clinically healthy or affected with ADH or PDH (p = 0.306).

Conclusions

Higher incidence of hypertension and albuminuria, not microalbuminuria was seen in dogs affected with HAC compared to clinically healthy dogs; incidence of hypertension and albuminuria was significantly higher in dogs affected with ADH compared to PDH. However, presence of albuminuria was not correlated with systemic blood pressure.     

Canine symmetrical lupoid onychodystrophy: a retrospective study with particular reference to management

The records of six dogs in which a diagnosis of symmetrical lupoid onychodystrophy (SLO) had been made were examined retrospectively. The age at onset ranged from six months to eight years. All the dogs had been presented with onycholysis, onychomadesis, onychalgia and onychodystrophy. The diagnosis of SLO was confirmed in all cases by histological examination. Histological features were similar in all cases and included hydropic degeneration of the basal cell layer, pigmentary incontinence and a cell-rich interface dermatitis. Response (defined as good, partial or failure) to various therapies was compared. Treatments (as initial therapy or following previous treatment failure) included essential fatty acids (EFA) (three cases), a combination of tetracycline and nicotinamide (four cases) and azathioprine and/or prednisolone (one case each). EFA therapy resulted in one good response, one partial and one failure, tetracycline and nicotinamide in two good responses, one partial and one failure, and azathioprine and/or prednisolone in one good and one partial response. Although all treatments were successful in some cases, none was universally effective.