Detection of serum alpha-fetoprotein in dogs with naturally occurring malignant neoplasia

Serum alpha-fetoprotein (AFP) concentrations were determined, by use of an automated microparticle enzyme-linked immunoassay (MEIA), in 16 control dogs and 48 dogs with previously untreated, histologically confirmed, naturally occurring neoplasia (17 dogs with lymphoma and 31 dogs with nonhematopoietic malignancies, 13 dogs with carcinomas, 18 dogs with sarcomas). Mean serum AFP concentrations for untreated dogs with lymphoma, for dogs with sarcomas, and for dogs with carcinomas were not significantly different from the mean serum AFP concentration for the 16 untreated control dogs. Mean serum AFP concentration for dogs with transitional cell carcinoma (n=7) was not significantly different from the mean serum AFP concentration for the control dogs. It has been shown previously by others that a mean serum AFP concentration > 225 ng/mL is suggestive of a hepatic malignancy (e.g., hepatocellular carcinoma, lymphoma). In our study, all 48 dogs had a normal complete blood count, serum biochemical analysis, and urinalysis. Only one of the 48 dogs was found to have a serum AFP concentration > 225 ng/mL. Later evaluation of this dog confirmed hepatic involvement with lymphoma. AFP can be detected in the serum of dogs with naturally occurring tumors using the MEIA technique. A serum AFP concentration above that observed in normal dogs is not a common finding in dogs with naturally occurring neoplasia; however, we confirmed that a serum AFP concentration > 225 ng/mL, with or without evidence of a serum biochemical abnormality, may suggest primary and/or secondary hepatic involvement with a neoplastic disease and may warrant an adjustment in clinical stage and prognosis. A prospective diagnostic and therapeutic evaluation of dogs, with naturally occurring tumors having an elevated serum AFP concentration would determine the validity of this conclusion.     

Evaluation of an insulin zinc suspension for control of naturally occurring diabetes mellitus in dogs

OBJECTIVE: To evaluate duration of action of an insulin zinc suspension (Caninsulin, Intervet) in spontaneously occurring cases of canine diabetes mellitus and suitability of its use as a once daily administered insulin for treatment of this disease. DESIGN: Eight client-owned canine diabetics were included in a prospective pilot study. All dogs had been treated with Caninsulin for a minimum of 2 months and were considered on clinical grounds to be adequately stabilised. PROCEDURE: Dogs were hospitalised for 24 h and blood collected every 2 h via indwelling venous catheters for blood glucose determination. RESULTS: Once daily Caninsulin administration failed to maintain glycaemic control for greater than 13 h in five of eight dogs, but acceptable blood glucose concentrations were maintained for 22 h and greater than 24 h in two others. One dog became distressed during hospitalisation and the blood glucose curve did not show an identifiable response to the insulin. CONCLUSION: Most diabetic dogs may require twice daily administration of Caninsulin for satisfactory glycaemic control, but once daily administration may be adequate in some animals. More comprehensive investigation into duration of activity of Caninsulin is warranted.     

Field evaluation of the efficacy and safety of a combination of spinosad and milbemycin oxime in the treatment and prevention of naturally acquired flea infestations and treatment of intestinal nematode infections in dogs in Europe

Two separate randomised, blinded, multicentre field trials were conducted to evaluate the efficacy and safety of a combination of spinosad and milbemycin oxime (MO) (Trifexis^®, Elanco Animal Health) in the treatment and prevention of naturally acquired flea infestations and intestinal nematode infections in European dogs. Treatments using Trifexis^® and each control veterinary product (CVP) were administered once on Day 0 in both field studies.In the flea field trial, 11 veterinary clinics in France participated in the study. On Day 0, whole body flea comb counts were conducted on all dogs being evaluated for enrolment. Dogs with ≥7 fleas on Day 0 were enrolled, treated once on Day 0 with spinosad/MO or the CVP (Stronghold^®; selamectin) and then underwent post-treatment flea counts on Days 14 and 30. There were 150 spinosad/MO treated dogs and 71 CVP treated dogs included in the flea effectiveness population. Effectiveness against fleas (% reduction in geometric means; GM) was 98.97% and 97.37% for the spinosad/MO treated dogs, and 97.43% and 93.96% for the CVP dogs on Days 14 and 30, respectively, compared to the pre-treatment baseline flea counts. Of the spinosad/MO dogs, 89.3% and 80.0% had no live fleas on Days 14 and 30, compared to 77.5% and 70.4% of the CVP dogs, respectively.In the nematode field trial, data from 10 veterinary clinics in France and 19 in Ireland were pooled. Faecal samples from dogs at each clinic were analysed. A positive result at screening (parasite eggs from Toxocara canis, Toxascaris leonina, Trichuris vulpis or Ancylostoma caninum) allowed for enrolment. Dogs were randomised to spinosad/MO or the CVP (Milbemax^®; MO/praziquantel). On Day 8, a post-treatment faecal sample was taken and analysed. Of 2333 dogs screened for nematode eggs, 238 dogs were positive with one or more of these nematodes, and 229 were enrolled in the study. Of the 229 dogs, 151 were treated with a single dose of spinosad/MO, and 77 were treated with a single dose of CVP. Post-treatment effectiveness against all nematodes (% reduction GM) was achieved with reductions of 98.57% and 97.57% for the spinosad/MO treated dogs and CVP dogs, respectively, as compared to the pre-treatment baseline faecal egg counts.Trifexis^® was shown to be safe and effective against natural infestations of fleas as well as mixed and single intestinal nematode infections in client owned dogs in Europe when administered as a single oral administration at the recommended dose.     

Retrospective evaluation of notched and fragmented QRS complex in dogs with naturally occurring myxomatous mitral valve disease

Myxomatous mitral valve disease (MMVD) is the most common cardiac disease in dogs. The association of QRS notching (nQRS) or fragmentation (fQRS) with disease severity is currently unknown. The study objective was to assess the prevalence of nQRS and fQRS in dogs with MMVD and its severity according to ACVIM classification and to compare the results with a group of healthy dogs. This retrospective cross-sectional study included 34 healthy control dogs and 155 dogs with spontaneous MMVD (42% of dogs in class B1, 23% in class B2 and 35% in class C). fQRS was defined as nQRS complexes in two contiguous leads in the frontal plane (leads I and aVL) and (II, III or aVF). A one-way ANOVA with Bonferroni post-hoc test was used to assess the differences in continuous data between control and MMVD groups. Of the MMVD group, 58% showed nQRS in at least one lead and 27% presented fQRS. There was no difference between the number of leads with a nQRS and disease severity (p = 0.75) nor did the number of leads with a nQRS correlate with left atrial size (r = 0.48; p = 0.5). The number of dogs with fQRS did not differ among classes of MMVD (p = 0.21). nQRS and fQRS were more prevalent in dogs with MMVD compared to control dogs (p < 0.01). This study did not identify any relationship between the number of leads with a nQRS and disease severity. However, dogs with MMVD had a higher prevalence of nQRS and fQRS compared to control group.     

Doxorubicin area under the curve is an important predictor of neutropenia in dogs with naturally occurring cancers

Doxorubicin (DOX) area‐under‐the‐curve (AUC) was calculated for 40 dogs with spontaneously occurring cancers using a previously validated limited‐sampling approach. All dogs were administered a dose of 30 mg/m² by intravenous infusion and serum samples were collected at 5, 45 and 60 minutes post‐infusion. DOX and its major metabolite, doxorubicinol (doxol), were quantified in serum samples using high‐performance liquid chromatography tandem‐mass spectrometry. Wide interpatient variability was observed in the predicted DOX AUC with a coefficient of variation of 34%. A significant relationship was found between DOX AUC and absolute white blood cell count (P = 0.003), absolute neutrophil count (ANC; P = 0.002) and surviving fraction of neutrophils (P = 0.03) approximately 1 week after dosing (nadir). No changes in other hematologic parameters (red blood cells, platelets, lymphocytes, haemoglobin) were found to correlate with DOX AUC. The absolute dose (mg) and the dose per unit body weight (mg/kg) were not significantly correlated with nadir ANC. No relationships were found between maximum serum doxol concentration and myelosuppression. Baseline ANC was also significantly correlated to nadir ANC and a model was constructed using baseline ANC and DOX AUC that significantly described the nadir ANC. These findings demonstrate the important relationship between systemic DOX exposure and degree of neutropenia in dogs, and suggest a potential for individualized, pharmacokinetically‐guided DOX dosing in dogs.     

Phase I and pharmacokinetic evaluation of the combination of orally administered docetaxel and cyclosporin A in tumor-bearing cats

Intravenously administered docetaxel (DT) is problematic in cats because of the requirement for premedication to ameliorate acute vehicle-induced hypersensitivity reactions. Previously we have revealed that therapeutic plasma concentrations of DT can be achieved in normal and tumor-bearing dogs when DT is administered PO in combination with oral cyclosporin A (CSA). The purpose of this study was to identify the maximally tolerated dosage and characterize the pharmacokinetic disposition of oral DT combined with CSA in cats with tumors. Eighteen tumor-bearing cats were enrolled in this phase I dose escalation and pharmacokinetic study. DT was administered by gavage with CSA (5 mg/kg) twice over a 3-week period. The starting dose of DT was 1.0 mg/kg. Based on the clinical toxicity profile, with gastrointestinal adverse effects and hematologic toxicity the maximal tolerated dose of oral DT was 1.75 mg/kg in combination with 5 mg/kg CSA. Additional studies are necessary to determine the efficacy of DT/CSA in cats with epithelial tumors.     

Phase II, open-label trial of single-agent CCNU in dogs with previously untreated histiocytic sarcoma

Background: Histiocytic sarcoma (HS) is an aggressive neoplasm in dogs, and in most instances, the disease is localized, but not amenable to surgical removal, or is disseminated. Affected patients usually die within 6 months. There have been no prospective studies to determine efficacy of single‐agent chemotherapy in dogs with HS. Hypothesis: Single‐agent CCNU [1‐(2‐chloroethyl)3‐cyclohexyl‐1‐nitrosourea; lomustine] has antitumor activity against HS in dogs. Animals: Twenty‐one dogs with histologically confirmed, nonresectable localized or disseminated HS. Methods: Prospective, open‐label phase II clinical trial in which dogs with previously untreated HS were uniformly treated with CCNU as a single oral dosage of 90 mg/m² every 4 weeks. The primary outcome measure was reduction in tumor size. Results: Fourteen dogs with disseminated HS and 7 with localized HS were enrolled between 1999 and 2008. Overall response rate was 29% (95% confidence interval [CI], 14–50%) for a median of 96 days (95% CI, 55–137 days). Three dogs (1 disseminated, 2 localized) had complete responses lasting for 54–269 days and 3 dogs (2 disseminated, 1 localized) had partial responses lasting for 78–112 days. Conclusions and Clinical Importance: CCNU, when used as a single agent, has activity against HS in dogs. Evaluation of CCNU postoperatively for dogs with resectable localized HS and as part of combination therapy for tumors that are nonresectable or disseminated should be considered.     

Clinical signs,diagnosis and treatment of three dogs with angiostrongylosis in Ireland

: Infection with Angiostrongylus vasorum was diagnosed at necropsy on a dog that died from acute pulmonary haemorrhage, and on recovery of L1 larvae by Baermann examination of faeces from two dogs, one of which had abdominal pain and retroperitoneal haemorrhage, while the other had right-sided heart failure due to cor pulmonale. The presenting signs included syncope (one dog), exercise intolerance (two dogs), cough (two dogs), abdominal pain (one dog) and depression (one dog). One-stage prothrombin time and activated partial thromboplastin time were prolonged in two dogs, buccal mucosal bleeding time was prolonged in one dog and globulin was elevated in all three dogs. Two dogs were treated with fenbendazole and recovered.     

Clinical pharmacokinetics and outcomes of oral fluconazole therapy in dogs and cats with naturally occurring fungal disease

This multi-institutional study was designed to determine the clinical pharmacokinetics of fluconazole and outcomes in client-owned dogs (n = 37) and cats (n = 35) with fungal disease. Fluconazole serum concentrations were measured. Pharmacokinetic analysis was limited to animals at steady state (≥72 hr of treatment). The mean (range) body weight in 31 dogs was 25.6 (2.8–58.2) kg and in 31 cats was 3.9 (2.4–6.1) kg included in pharmacokinetic analyses. The dose, average steady-state serum concentrations (C_SS), and oral clearance in dogs were 14.2 (4.5–21.3) mg/kg/d, 26.8 (3.8–61.5) µg/mL, and 0.63 ml min⁻¹ kg⁻¹, respectively, and in cats were 18.6 (8.2–40.0) mg/kg/d, 32.1 (1.9–103.5) µg/mL, and 0.61 ml min⁻¹ kg⁻¹, respectively. Random inter-animal pharmacokinetic variability was high in both species. Two dogs had near twofold increases in serum fluconazole when generic formulations were changed, suggesting lack of bioequivalence. Median C_SS for dogs and cats achieving clinical remission was 19.4 and 35.8 µg/ml, respectively. Starting oral doses of 10 mg/kg q12h in dogs and 50–100 mg total daily dose in cats are recommended to achieve median C_SS associated with clinical remission. Due to the large pharmacokinetic variability, individualized dose adjustments based on C_SS (therapeutic drug monitoring) and treatment failure should be considered.     

The effect of dietary corn oil and fish oil supplementation in dogs with naturally occurring gingivitis

The aim of this randomized, double‐blinded, placebo‐controlled study was to evaluate if downregulation of the inflammatory response due to ingestion of high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can slow down gingivitis development, and thus delay the progression of periodontal disease (PD) in dogs. To this aim, 44 client‐owned adult dogs (>1 and <8 years old) with naturally occurring PD (stages 1 and 2) were submitted to a plaque, gingivitis and calculus scoring followed by a dental cleaning procedure and collection of blood samples. The animals were then fed a canine adult maintenance diet, supplemented with either corn oil (0.00 g EPA and 0.00 g DHA) or fish oil (1.53 g EPA and 0.86 g DHA, both per 1,000 kcal ME) over the following 5 months. At the end of this period, the PD scoring and the blood sampling were repeated. The animals consuming fish oil had higher plasma levels of the longer chain (C ≥ 20) omega 3 fatty acids (p < 0.01) and similar plasma levels of alpha‐linolenic acid (p = 0.53), omega 6 fatty acids (p > 0.63) and C reactive protein (p = 0.28) then the ones consuming corn oil. There were no differences between fish oil and corn oil diet supplementation on plaque (18.2 vs. 17.8, p = 0.78), calculus (10.1 vs. 11.5, p = 0.18) or gingivitis (19.3 vs. 19.0, p = 0.77) indexes. The authors conclude that supplementation with EPA + DHA does not slow down progression of PD in dogs.     

Evaluation of the efficacy and safety of a novel formulation of metaflumizone plus amitraz in dogs naturally infested with fleas and ticks in Europe

The efficacy and safety of a novel spot-on formulation of metaflumizone plus amitraz (ProMeris/ProMeris Duo for Dogs, Fort Dodge Animal Health, Overland Park, KS) was assessed in dogs naturally infested with ticks and/or fleas in a multiregional, clinical field study. Nineteen veterinary clinics in Germany and 11 clinics in France enrolled patients to the study. One hundred eighty one dogs with tick infestation and 170 dogs with flea infestation (plus three dogs harboring both ticks and fleas) qualified as primary patients and were randomly allocated to one of two treatments in a ratio of approximately 2:1 for metaflumizone plus amitraz (minimum dosage of 20 plus 20mg/kg) or fipronil (at the recommended label rate). Clinical examinations and baseline parasite counts were performed on Day 0 prior to treatment. Tick and/or flea counts and safety evaluations were repeated at intervals of about 2 weeks for 8 weeks. Both products resulted in consistent reductions in tick numbers (>81%) throughout the study, with metaflumizone plus amitraz giving consistently higher reductions in tick numbers. The efficacy against tick count compared with Day 0 was 97.6%, 93.5%, 89% and 94% at Day 14, 28, 42 and 56, respectively, for metaflumizone plus amitraz. The corresponding efficacies for fipronil were 86.3%, 81.1%, 84.8% and 86.1%. Within groups, the tick reduction was highly significant (P<0.0001) compared to baseline at all observation periods. Both treatments resulted in consistent (>89%) and highly significant (P<0.0001) reductions in flea numbers relative to the baseline counts throughout the study, although fipronil resulted in numerically higher reductions on each count day. The efficacy against fleas compared to baseline was 91.8%, 88.7%, 91.5% and 92.0% at Day 14, 28, 42 and 56, respectively, for metaflumizone plus amitraz. The corresponding efficacies for fipronil were 98.2%, 96.3%, 95.9% and 96.7%. Metaflumizone plus amitraz was highly effective in controlling existing infestations of fleas and ticks on dogs and was effective against reinfestation for at least 56 days. Metaflumizone plus amitraz showed a good tolerance profile in dogs.     

Evaluation of 1,2-O-dilauryl-rac-glycero glutaric acid-(6′-methylresorufin) ester (DGGR) and 1,2-diglyceride lipase assays in dogs with naturally occurring hypercortisolism

1,2-O-dilauryl-rac-glycero glutaric acid-(6′-methylresorufin) ester (DGGR) lipase activity has been proposed as a faster and less expensive test used in the diagnosis of acute pancreatitis (AP) compared to canine pancreatic lipase immunoreactivity (cPLI), which is considered the most sensitive and specific serum test available for dogs. Elevations in lipase activity have been observed in dogs with naturally occurring hypercortisolism (HC) and in those treated with exogenous steroids, which complicates the diagnosis of AP in dogs with HC. We compared lipase activity measured by DGGR and 1,2-diglyceride (1,2-DiG) assays in 22 dogs with HC, 22 with AP, and 22 healthy dogs. The dogs with HC had no clinical signs or ultrasonographic findings consistent with AP. DGGR lipase activity was elevated in 64% and 73% of the dogs with HC and AP, respectively, and in 18% of healthy dogs. 1,2-DiG lipase activity was high in 23% and 36% of the dogs with HC and AP, respectively, and in 5% of the healthy dogs. Both DGGR and 1,2-DiG lipase activities were significantly different between the healthy dogs and the other 2 groups, whereas no differences were detected between the dogs with HC and those with AP. Our results support a lack of specificity for both DGGR and 1,2-DiG lipase activity assays in aiding the diagnosis of AP in dogs with HC.     

A dose-finding,long-term study on the use of calcium chloride in saline solution as a method of nonsurgical sterilization in dogs: evaluation of the most effective concentration with the lowest risk

Background

Canine overpopulation is a global issue with serious health and welfare implications. Nonsurgical methods of sterilization could yield positive impacts on this problem, but no long-term data on such methods are available. The objective of the current investigation was to determine the effects of intratesticular injections of calcium chloride dihydrate (CaCl₂) in saline in dogs over a one year period. Five concentrations (0%, 10%, 20%, 30%, 60%) of CaCl₂ in saline were administered via intratesticular injection to groups of 10 dogs each. Total sperm count and motility, blood levels of testosterone, and side effects were examined at 0, 2, 6, and 12 months post-injection (PI). Testicular size and semen volume were examined at 0 and 12 months PI.

Results

Total sperm count, semen volume and testosterone showed significant dose-dependent decreases upon treatment with 10%-60% CaCl₂ compared with either the control group (0% CaCl₂) or baseline for each treatment group. Azoospermia was achieved for at least 12 months PI in 60% and 80% of treated dogs after administration of a 10% and 20% CaCl₂, respectively. Treatment with 30% or 60% CaCl₂ resulted in azoospermia in 100% of dogs, but more side effects were observed, while no side effects were noticed at lower doses. For each treatment group, testosterone levels had decreased an average of 35%-70% at 6 months following treatment. However, testosterone levels rebounded by the 12-month time point in all groups except the highest dosage group (60% CaCl₂), which remained at the low end of physiological range throughout the study. Sperm motility dropped to zero or near zero in all dogs treated with CaCl₂. Testicular size was significantly smaller at 12 months PI for all groups when compared to baseline.

Conclusions

This first long-term study confirms reports of the efficacy of CaCl₂ sterilization. However, at dosages free of adverse events, calcium chloride in saline may not provide permanent sterilization as previously believed. Future work should explore optimized solvents to increase the permanence of the well-tolerated 20% formulation.