This double-blinded noninferiority clinical trial evaluated the use of oral fluconazole for the treatment of Malassezia dermatitis in dogs by comparing it with use of an accepted therapeutic agent, ketoconazole. Dogs presenting with Malassezia dermatitis were treated with either fluconazole or ketoconazole in addition to cephalexin for concurrent bacterial dermatitis. Statistically significant improvements in cytologic yeast count, clinical signs associated with Malassezia dermatitis, and pruritus were seen with both antifungal treatments. There was no statistical difference between the treatments with regard to the magnitude of reduction in these parameters. These results suggest that fluconazole is at least as effective as ketoconazole for the treatment of dogs with Malassezia dermatitis.
The in vitro activity of 10 cephalosporin antimicrobial agents against 75 isolates of methicillin-susceptible Staphylococcus pseudintermedius derived from dogs was assessed. The lowest minimal inhibitory concentration for 90% of strains (MIC90) values obtained were for cephalothin, cefovecin, and cefazolin (0.12 ug/mL), followed by ceftiofur and cefoxitin (0.25 ug/mL), cefpodoxime (0.5 ug/mL), and cefaclor and cefadroxil (1 ug/mL). The highest MIC90 values were found for cephalexin and cefixime (2 ug/mL). In this in vitro study, sensitivity to cephalothin was indicative of cephalexin susceptibility, although there were marked differences in MICs. Cephalothin susceptibility was not indicative of susceptibility to all tested cephalosporins, nor was there a clear trend in susceptibility based on cephalosporin generation.
This pilot study evaluated protection of an equine autogenous bacterin-toxoid vaccine against Corynebacterium pseudotuberculosis infection. Twenty-four BALB/c mice were inoculated with two doses of bacterin-toxoid vaccine or two injections of a placebo. Clinical, microbiologic, and pathologic outcomes were assessed after intradermal infection with one of two equine-origin C. pseudotuberculosis strains. Mice receiving bacterin-toxoid from fast-growing C. pseudotuberculosis showed significant protection from challenge infection, as evidenced by a higher survival rate, fewer gross and histopathologic lesions, and lower bacterial levels on culture. Successful protection via a vaccine against equine internal abscesses might provide supplementary management options against an important, potentially fatal disease.
Assay-based chemotherapeutic protocols are common in human gynecologic oncology, most notably for patients with ovarian or breast cancer. The current study examines ex vivo incubation conditions necessary for the assessment of sarcomatous tumor response to potential chemotherapeutic drugs. Slices of sarcomatous tumors were incubated in one of two culture media. Viability indices were measured and compared across time and between media. Neither medium was sufficient to support the growth of sarcomatous tumor tissue slices based on the indices studied. It is likely that sarcomatous tumors require a different approach for ex vivo assessment than their epithelial counterparts. Our long-term goal is to incubate tumor slices with chemotherapeutic agents to predict the in vivo tumor response based on the maintenance or loss of slice viability within this system.
Methimazole (thiamazole) is an antithyroid drug commonly used to treat feline hyperthyroidism. It is routinely given twice daily. Carbimazole is a methimazole derivative that is rapidly metabolized to methimazole in vivo. A controlled-release tablet for once-daily carbimazole therapy has recently been developed in an attempt to improve compliance during medical management of feline hyperthyroidism. The results of a crossover study in six cats suggest that the pharmacokinetics of methimazole with a single dose of this controlled-release tablet may be similar to those with a single dose of a sugar-coated methimazole tablet when the two drugs are given at an equimolar dose. The mean half-lives were nearly identical (3.12 hours, sugar-coated methimazole tablets; 3.28 hours, controlled-release carbimazole tablets). The serum concentrations of methimazole at 24 hours were 21.7 ± 28.9 ng/mL in the cats treated with 5-mg sugar-coated methimazole tablets and 28.7 ± 37 ng/mL in the cats treated with 10-mg carbimazole tablets (which provide approximately 25% more methimazole after conversion to the active metabolite).
There is no labeled treatment for dogs with American canine hepatozoonosis (ACH), but the drug therapies discussed in this article, although not rapidly curative, may be successful in alleviating acute clinical signs, prolonging life, reducing the number of clinical relapses, and enhancing quality of life. This article also describes a pilot trial conducted to assess the efficacy of a novel treatment approach with ponazuril as a stand-alone parasiticide administered for 4 weeks without follow-up decoquinate treatment. Although extended ponazuril treatment in combination with NSAID administration did ameliorate acute clinical signs associated with ACH, the parasite was not completely cleared with this treatment protocol alone. Long-term decoquinate therapy remains a critical component of successful treatment of ACH.
To investigate the cutaneous distribution, localization, and persistence of imidacloprid in dogs, Advantage Topical Solution labeled with carbon 14 ((14)C) was topically applied as a single treatment at label rates and application pattern based on body weight to two adult beagles. One dog (8.5 kg) received 1.0 mL of the test solution at a single spot in the interscapular area (14 mg active ingredient/kg body weight); the second dog (12.3 kg) was treated with 2.5 mL of the test solution at four sites, each site receiving approximately 0.625 mL, along the dorsal thoracic and lumbar spine area (21 mg active ingredient/kg body weight). Samples of hair, skin surface residue, and skin taken from the application sites and/or distal body regions of the dogs at four intervals between 7 and 56 days after treatment demonstrated the migration of (14)C radioactivity from the application sites to distal areas of the canine haircoat and skin. The (14)C radioactivity concentrations in the skin biopsy and stratum corneum samples diminished steadily over 56 days after treatment. Microautoradiography of the skin showed focal concentrations of radioactivity in the superficial epidermis, hair follicles, and sebaceous glands. The presence of imidacloprid-derived radioactivity within hair follicles and sebaceous glands and on the skin surface is in good agreement with the reported efficacy of imidacloprid against fleas on dogs and cats for up to 1 month despite posttreatment bathing, shampooing, and/or swimming.
The goal of glaucoma management is to reduce intraocular pressure (IOP) and maintain it at a level compatible with the health of the optic nerve. New therapies are constantly being sought. Topical instillation of levobunolol 0.5%, alone or with dorzolamide 2%, has a hypotensive effect on the IOP in healthy dogs, and levobunolol combined with dorzolamide produces a stronger hypotensive effect than the combination of timolol and dorzolamide. All animals tolerate these topical medications well with no signs of discomfort, and no ocular side effects have been observed. Levobunolol, alone or in combination with dorzolamide, induces bradycardia, as does timolol with dorzolamide.
A Borrelia burgdorferi antibody screening and vaccination program was established at a 2.5-doctor small animal hospital where no prior program had existed. A commercially available nonadjuvanted recombinant outer surface protein A vaccine was given at day 0, 3 weeks, and 6 months and then yearly based on recommendations by Topfer and Straubinger. Analysis of Lyme-specific serologic results in the hospital's canine patient population over a 33-month period showed that >99% of C6 Lyme antibody-positive dogs had not been immunized, were previously C6 antibody positive, or had not completed the hospital's recommended vaccine protocol. Additionally, the overall seroprevalence of B. burgdorferi C6 antibody decreased in the patient population during the postvaccination period.
In the past 5 years, the incidence of canine skin infections caused by resistant strains of Staphylococcus (pseud)intermedius has increased. Many older antibiotics are used to treat these infections because the sensitivity can be demonstrated in vitro. Additionally, many of these older drugs are efficacious and unlikely to induce multidrug resistance. More than a decade ago, the antibiotic tylosin tartrate was reported to be efficacious in vitro and in vivo against Staphylococcus intermedius. The purpose of this study was to determine whether S. (pseud)intermedius isolated from untreated pyoderma cases at veterinary referral centers across the United States are sensitive in vitro to this antibiotic. Minimum inhibitory concentrations for tylosin tartrate and other commonly used antibiotics were determined for 103 isolates. Most (82.61%) of the isolates not exposed to antibiotics in the 3 months before submission were sensitive to tylosin tartrate. These findings suggest that tylosin tartrate warrants further study as a first-line option for the treatment of dogs initially presenting with pyoderma.
Alternatives to intravenous administration of opioids are needed in veterinary medicine. Previous research suggests that opioids can be administered through the buccal mucosa in dogs. This study reports the pharmacokinetics of buprenorphine HCl (0.05 mg/kg) administered transmucosally in six dogs compared with those of buprenorphine HCl (0.015 mg/kg) administered intravenously. The results suggest that the pharmacokinetics of buprenorphine HCl administered intravenously or transmucosally are similar and that transmucosal administration may be considered as a noninvasive alternative to intravenous administration.
Although probiotics are generally considered to be safe, their increasingly widespread use warrants better understanding of their risks in companion animals. This study evaluated the safety and tolerance of dietary supplementation with a canine-derived probiotic, Bifidobacterium animalis strain AHC7 (Prostora, Procter & Gamble Pet Care), fed to growing beagles beginning at approximately 6 months of age (11 males; 9 females). Probiotic B. animalis AHC7 administered orally once per day at a dose of up to 5 x 1010 colony-forming units for at least 12 consecutive weeks was well tolerated with no safety concerns.
This double-blinded noninferiority clinical trial evaluated the use of oral fluconazole for the treatment of Malassezia dermatitis in dogs by comparing it with use of an accepted therapeutic agent, ketoconazole. Dogs presenting with Malassezia dermatitis were treated with either fluconazole or ketoconazole in addition to cephalexin for concurrent bacterial dermatitis. Statistically significant improvements in cytologic yeast count, clinical signs associated with Malassezia dermatitis, and pruritus were seen with both antifungal treatments. There was no statistical difference between the treatments with regard to the magnitude of reduction in these parameters. These results suggest that fluconazole is at least as effective as ketoconazole for the treatment of dogs with Malassezia dermatitis.
This study determined the antimicrobial activity of tulathromycin against Rhodococcus equi in vitro. Ninety-eight virulent isolates of R. equi from equine clinical cases were examined, of which 20 isolates were macrolide resistant. A custom 96-well antimicrobial susceptibility testing plate was used, allowing 14 additional antimicrobials to be tested against R. equi. Isolates were cultured with various concentrations of antimicrobials, and minimal inhibitory concentration (MIC) values were determined. Tulathromycin was found to have poor activity in vitro against R. equi isolates susceptible or resistant to macrolides, with MIC50 and MIC90 values >64 ug/mL for all isolates. MIC values for other macrolides tested were similar to previously published data.
Stem cells and their potential therapeutic uses in human and veterinary medicine have generated considerable interest. These cells have a number of potentially unique immunologic properties; most notable are their reported regenerative and antiinflammatory capabilities. The aim of this prospective pilot study was to evaluate the efficacy of intravenously administered autogenous adipose-derived mesenchymal stem cells (AD-MSCs) in the treatment of canine atopic dermatitis. AD-MSCs administered intravenously at a dose of 1.3 million cells/kg did not significantly reduce the clinical signs of canine atopic dermatitis or the owner-assessed pruritus level.
This study investigated the dose dependency of the hemodynamic effects of IV medetomidine (MED) constant-rate infusion (CRI) during isoflurane anesthesia. Twenty-four healthy beagles randomly received one of six MED CRI regimens. A loading dose of MED was administered IV at 0.2, 0.5, 1.0, 1.7, 4.0, or 12.0 ug/kg-1 for 10 minutes, followed by a maintenance CRI providing identical dose amounts over 60 minutes. Heart rate and mean arterial blood pressure were recorded, blood gases were analyzed, and cardiac index (CI) was determined. Statistical analysis involved a repeated measures linear model. Baseline CI demonstrated a dose-dependent decrease as the MED dose increased, with decreases of 14.9% (SD, 12.7%), 21.7% (17.9%), 27.1% (13.2%), 44.2% (9.7%), 47.9% (8.1%), and 61.2% (14.1%) at doses of 0.2, 0.5, 1.0, 1.7, 4.0, and 12.0 ug/kg-1, respectively. The four lowest doses induced limited and transient changes in heart rate, mean arterial pressure, and CI. Further investigation into potential perioperative uses of MED CRI is warranted.
Pituitary pars intermedia dysfunction (PPID) is probably the most common disease of geriatric horses. Affected horses show a variety of clinical signs, including hirsutism, polyuria/polydipsia, immunosuppression, muscle wasting, and laminitis. The most common treatment for PPID is pergolide, a dopamine agonist; however, there are no pharmacokinetic data about the use of this drug in horses. This article describes a study designed to address this complete lack of pharmacokinetic information. The pharmacokinetics of pergolide are described in a small group of relatively young, healthy mares (n = 6), with the objective of generating data on which to base larger studies in the future. To make definitive dosing recommendations to clinicians, more studies will be needed to investigate the relationship between plasma pergolide concentrations and clinical outcomes, as well as the effect of gender, age, and concomitant disease on the absorption and disposition of this drug.
In vitro activity of ceftiofur and six other antimicrobial agents was assessed for 516 Streptococcus equi subsp zooepidemicus isolates collected from horses with lower respiratory tract infections in North America in 2007 and 2008 and 239 equine S. equi subsp zooepidemicus isolates received from US and Canadian veterinary diagnostic laboratories between 1989 and 2007. The lowest concentration of ceftiofur inhibiting the growth of 90% of the isolates (MIC90) was 0.12 microg/ml for both groups of isolates. The Clinical and Laboratory Standards Institute susceptible breakpoint set for ceftiofur against this organism is a minimal inhibitory concentration value of ≤ 0.25 microg/ml. The MIC90 values remained consistent for isolates collected over 19 years.
Canine influenza virus (CIV) subtype H3N8 is an emerging pathogen with sustained horizontal transmission in the dog population in the United States. This study evaluated the efficacy of an inactivated CIV vaccine in 6- to 8-week-old beagle pups challenged with virulent CIV. One group of CIV-seronegative pups was vaccinated with two doses of a CIV vaccine 3 weeks apart; a second group of pups received adjuvanted placebo as a control. Blood samples were collected at various times to determine antibody titers. All pups were challenged with a virulent CIV isolate 13 days after the second vaccination and monitored for clinical signs of respiratory disease, virus shedding, and lung consolidation. Vaccinated pups developed hemagglutination inhibition antibody titers after vaccination. The severity of clinical signs (P < .001) and the magnitude and duration of virus shedding (P < .0001) were significantly lower in vaccinated pups compared with control pups. These results demonstrate that the CIV vaccine used in this study provides protection against virulent CIV challenge in dogs.
In vitro activity of ceftiofur and six other antimicrobial agents was evaluated against 79 Streptococcus equi subsp zooepidemicus isolates collected from horses with respiratory disease in Europe during 2007 and 2008. In addition, the in vitro activity of ceftiofur and other antimicrobial drugs was assessed against 59 S. equi subsp zooepidemicus and 49 S. equi subsp equi isolates collected by veterinary diagnostic laboratories in Europe from 2002 to 2006. The lowest concentration of ceftiofur that inhibited the growth of 90% of the isolates (MIC90) was 0.12 microg/ml, with the Clinical Laboratory Standards Institute-approved susceptible breakpoint set at ≤ 0.25 microg/ml for ceftiofur against S. equi subsp zooepidemicus. The MIC90 values remained consistent when comparing the isolates collected from diagnostic laboratories or from the field study.
