Prevalence of Demodex gatoi in shelter and feral cats in a southeastern region of the United States.

BACKGROUND: Demodex gatoi is a contagious ectoparasite that causes pruritic dermatitis in otherwise healthy cats. The diagnosis of this mite can be difficult, and its prevalence is unknown. OBJECTIVES: The goal of this study was to identify the prevalence of D. gatoi in a population of cats with no known previous exposure to treatments using real-time PCR and superficial skin scrapings. ANIMALS: Fifty cats from shelters and 50 cats from feral populations of eastern Tennessee were included in this study. MATERIALS AND METHODS: To identify the presence of D. gatoi, superficial skin scrapings and plucked hairs were collected from multiple sites for microscopic and PCR evaluation, respectively. RESULTS: Ten of 100 cats were positive for D. gatoi. Nine cats had a positive PCR for D. gatoi with negative skin scrapings. One mite was identified on superficial skin scrapings from one cat, which was negative on PCR. Four of 50 feral cats (8%) were positive for D. gatoi. Of the shelter cats, four of 20 stray cats (20%) and two of 30 owner-surrendered cats (6.67%) were positive. Only one of 10 positive cats had skin lesions. CONCLUSIONS AND CLINICAL RELEVANCE: These findings demonstrate that asymptomatic cats represent a source of infection for D. gatoi to healthy cats. This mite should be considered a differential diagnosis in pruritic cats with a history of potential exposure. Additionally, skin scrapings appear to be insensitive; thus, multiple diagnostic tests, including PCR, should be performed to identify the presence of D. gatoi.

Effect of topical florfenicol, terbinafine and mometasone furoate ear drops on adrenocortical function in healthy small breed dogs with bilateral otitis externa.

BACKGROUND: Testing for hyperadrenocorticism is commonly pursued in adult dogs with dermatological disease, and adrenocortical suppression has been well-documented following the use of topical corticosteroids in otic preparations. An otic suspension that contains florfenicol, terbinafine and mometasone furoate, and lasts for 30 days after a single application, frequently is used to treat canine otitis externa (OE). This medication was shown to cause adrenocortical suppression on Day (D)2 postadministration and two weeks after two applications two weeks apart. HYPOTHESIS/OBJECTIVES: The objective of this study was to determine if topical florfenicol/terbinafine/mometasone furoate causes adrenocortical suppression in healthy, small-breed dogs with bilateral OE at D28 postapplication. ANIMAL: Seven client-owned dogs weighing <10 kg diagnosed with non-Pseudomonas bilateral OE. MATERIALS AND METHODS: Cortisol was measured pre- and post-adrenocorticotropic (ACTH) stimulation on D0. Topical florfenicol/terbinafine/mometasone furoate was applied in both ears. Dogs were reassessed on D28, and cortisol was measured pre- and post-ACTH stimulation. RESULTS: The median pre- and post-ACTH cortisol concentrations on D28 were 2.5 µg/dL (range 2.0-5.0 µg/dL) and 14.3 µg/dL (range 11.5-23.1 µg/dL), respectively. There was no significant difference (P = 0.85) between post-ACTH cortisol concentrations from D0 to D28. CONCLUSIONS AND CLINICAL RELEVANCE: Results demonstrated no evidence of adrenocortical suppression, suggesting that there is no need to delay adrenocortical function testing in dogs treated with topical florfenicol/terbinafine/mometasone furoate when applied as per the manufacturer's recommendations.

Vitamin A failed to ameliorate clinical signs in dogs with pituitary-dependent hypercortisolaemia.

BACKGROUND: In dogs with pituitary-dependent hypercortisolaemia, retinoic acid was shown to lower cortisol, reduce pituitary tumour size and decrease clinical signs when administered for six months. Oral vitamin A (retinol) has been used to treat various canine dermatoses in which retinoic acid has been efficacious. OBJECTIVES: To determine if orally administered vitamin A lowers cortisol and reduces clinical signs in dogs with pituitary-dependent hypercortisolaemia over a five month period. METHODS AND MATERIALS: Five dogs were enrolled in this study. Diagnosis of hypercortisolaemia was based on the presence of at least three clinical signs and one abnormal screening test. Diagnosis of pituitary-dependent disease was based on low dose dexamethasone suppression (LDDS) test results and symmetrical adrenal glands on ultrasound. Adrenocorticotropic hormone (ACTH) stimulation testing and adrenal ultrasound were performed at each visit. Plasma was collected at each visit and stored at -80°C for batch analysis of endogenous ACTH at conclusion of the study. RESULTS: Four dogs completed the study. A fifth dog died from complications of hypercortisolaemia before the third month. One dog showed improvement in clinical signs, yet there was no significant decrease in adrenal gland size or cortisol concentrations. Endogenous ACTH concentrations at the fifth month were decreased from baseline in two dogs and increased from baseline in one dog. The treatment had no adverse effects. CONCLUSIONS AND CLINICAL IMPORTANCE: Results from this study failed to show an improvement in clinical signs or cortisol concentration after five months of oral daily vitamin A in dogs with hypercortisolaemia.

Feline bilateral inflammatory aural polyps: a descriptive retrospective study.

BACKGROUND: Feline inflammatory aural polyps (IP) have been reported as solitary growths, yet bilateral polyps may occur more commonly than described previously. OBJECTIVES: To identify the prevalence and risk factors associated with bilateral feline IP within a population of cats evaluated at a veterinary teaching hospital over a 10 year period. ANIMALS: Twenty-five cats with histologically confirmed IP. METHODS AND MATERIALS: A retrospective study was performed by searching computerized medical records of cats seen at The University of Tennessee Veterinary Teaching Hospital from 2005 to 2015. Keywords used for the search included "feline polyp", "ventral bulla osteotomy", "inflammatory polyp ear canal" and "nasopharyngeal polyp". RESULTS: Cats were separated into groups with unilateral or bilateral disease. Six of 25 (24%) cats had bilateral IP. Twelve cats had computed tomography performed (four of six with bilateral IP; eight of 19 with unilateral IP). Clinical signs, history of upper respiratory infection, post-treatment complications, and IP recurrence with and without local and systemic steroid administration were studied between groups and no differences were identified. In four of six cats with bilateral disease, the second polyp was identified with advanced imaging performed at the time of referral. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings demonstrate that bilateral IP occur more frequently than reported previously and establish a prevalence for bilateral IP. These findings also highlight the value of advanced imaging techniques in diagnosing bilateral IP.

Staphylococcus pseudintermedius 5'-nucleotidase suppresses canine phagocytic activity.

Staphylococcus pseudintermedius is a major opportunistic bacterial pathogen and the leading cause of pyoderma in dogs. In canines it is also often associated with infections of the urinary system and wounds and occasionally infects people. Widespread antimicrobial resistance has made the development of alternative treatments a high priority. The development of a staphylococcal vaccine, however, has proven challenging. Identification of virulence factors that inhibit phagocytosis and avoid innate immunity may play a significant role in preventing or treating infection with S. pseudintermedius. In this study, we identified a putative 5'-nucleotidase provisionally named SpAdsA, a S. pseudintermedius cell- wall protein encoded by SpAdsA. SpAdsA shares approximately 52% identity with the orthologous protein of Staphylococcus aureus and 14.8% identity with that of Streptococcus suis type2. It catalyzes the dephosphorylation of adenosine triphosphate and attenuation of this enzyme with critical amino acid substitutions nearly eliminated its hydrolytic activity. Exogenous adenosine inhibited phagocytosis of S. pseudintermedius by canine neutrophils and monocytes. Conversely, the addition of SpAdsA inhibitor or A2A adenosine receptor antagonist impaired the capacity of S. pseudintermedius to escape from killing by phagocytic cells. The neutralizing ability of canine antibody produced against SpAdsA-M was determined. Taken together, these results suggest that SpAdsA likely plays an important role in S. pseudintermedius virulence and that attenuated SpAdsA may be a good candidate for inclusion in a vaccine against S. pseudintermedius.

Identification, cloning and characterization of SpEX exotoxin produced by Staphylococcus pseudintermedius.

Staphylococci have evolved numerous strategies to evade their hosts' immune systems. Some staphylococcal toxins target essential components of host innate immunity, one of the two main branches of the immune system. Analysis of the Staphylococcus pseudintermedius secretome using liquid chromatography mass spectrometry guided by genomic data, was used to identify an S. pseudintermedius exotoxin provisionally named SpEX. This exoprotein has low overall amino acid identity with the Staphylococcus aureus group of proteins named staphylococcal superantigen like proteins (SSLs) and staphylococcal enterotoxin- like toxin X (SEIX), but predictive modeling showed that it shares similar folds and domain architecture to these important virulence factors. In this study, we found SpEX binds to complement component C5, prevents complement mediated lysis of sensitized bovine red blood cells, kills polymorphonuclear leukocytes and monocytes and inhibits neutrophil migration at sub-lethal concentrations. A mutant version of SpEX, produced through amino acid substitution at selected positions, had diminished cytotoxicity. Anti-SpEX produced in dogs reduced the inhibitory effect of native SpEX on canine neutrophil migration and protected immune cells from the toxic effects of the native recombinant protein. These results suggest that SpEX likely plays an important role in S. pseudintermedius virulence and that attenuated SpEX may be an important candidate for inclusion in a vaccine against S. pseudintermedius infections.

Description and characterization of a hair coat disorder in schipperkes.

BACKGROUND: Schipperkes develop bilaterally symmetrical alopecia preceded by lightening of the hair coat not associated with systemic clinical signs. The alopecia is presumptively diagnosed as Alopecia X but has never been investigated. HYPOTHESIS/OBJECTIVES: The purpose of this study was to describe clinical features, histopathological and laboratory abnormalities associated with symmetrical, noninflammatory alopecia in schipperkes. ANIMALS: Three healthy and eight affected schipperkes. METHODS AND MATERIALS: Complete blood count (CBC), serum chemistry panel, urinalysis (UA), urine cortisol: creatinine ratio (UCCR), total thyroxine (T4 ), free thyroxine by equilibrium dialysis (fT4 ed), thyroid stimulating hormone (TSH) and pre- and post-stimulation cortisol with sex hormone analyses were performed for all dogs. A minimum of two skin biopsy sites were sampled for histopathological evaluation. RESULTS: The CBC, serum chemistry panel, UA, T4 , fT4 ed, TSH and post-ACTH cortisol concentrations were normal for all dogs. Androstenedione concentrations were increased for all dogs; two of three healthy and five of eight affected dogs had increased post-ACTH androstenedione concentrations. Estradiol concentrations were increased for all healthy and four of eight affected dogs, with post-ACTH estradiol concentrations increased for all healthy and five of eight affected dogs. Progesterone concentrations were increased for two of three healthy and four of eight affected dogs. Post-ACTH progesterone concentrations were increased for one of three healthy and four of eight affected dogs. For one of three healthy and two of eight affected dogs, 17-hydroxyprogesterone concentrations were increased; post-ACTH 17-hydroxyprogesterone concentrations were increased in three of eight affected dogs only. Histopathology results from affected dogs were consistent with hair cycle arrest. CONCLUSIONS AND CLINICAL IMPORTANCE: This disorder resembles Alopecia X clinically and histologically.

Characterization of a leukocidin identified in Staphylococcus pseudintermedius.

Bacterial infections from Staphylococcus pseudintermedius are the most common cause of skin infections (pyoderma) affecting dogs. Two component pore-forming leukocidins are a family of potent toxins secreted by staphylococci and consist of S (slow) and F (fast) components. They impair the innate immune system, the first line of defense against these pathogens. Seven different leukocidins have been characterized in Staphylococcus aureus, some of which are host and cell specific. Through genome sequencing and analysis of the S. pseudintermedius secretome using liquid chromatography mass spectrometry we identified two proteins, named "LukS-I" and "LukF-I", encoded on a degenerate prophage contained in the genome of S. pseudintermedius isolates. Phylogenetic analysis of LukS-I components in comparison to the rest of the leukocidin family showed that LukS-I was most closely related to S. intermedius LukS-I, S. aureus LukE and LukP, whereas LukF-I was most similar to S. intermedius LukF-I S. aureus gamma hemolysin subunit B. The killing effect of recombinant S. pseudintermedius LukS-I and LukF-I on canine polymorphonuclear leukocytes was determined using a flow cytometry cell permeability assay. The cytotoxic effect occurred only when the two recombinant proteins were combined. Engineered mutant versions of the two-component pore-forming leukocidins, produced through amino acids substitutions at selected points, were not cytotoxic. Anti-Luk-I produced in dogs against attenuated proteins reduced the cytotoxic effect of native canine leukotoxin which highlights the importance of Luk-I as a promising component in a vaccine against canine S. pseudintermedius infections.

The prevalence of Dermatophilus congolensis in horses with pastern dermatitis using PCR to diagnose infection in a population of horses in southern USA.

BACKGROUND: Dermatophilus congolensis is a facultative anaerobic actinomycete that causes papular to exudative dermatitis with crusting in horses. This organism is frequently implicated as a cause of pastern dermatitis, but few data are available validating the organism's association with this disease. HYPOTHESIS/OBJECTIVES: The aim of this study was to evaluate if D. congolensis is associated with pastern dermatitis in horses utilizing RT-qPCR. ANIMALS: Fifteen client-owned horses diagnosed with pastern dermatitis and eight client-owned unaffected control horses were utilized for this study. METHODS: A cross-sectional study was performed. History and physical examination findings were recorded, and samples were collected and tested for D. congolensis utilizing cytological evaluation and RT-qPCR. Dermatophyte culture and superficial skin scrapings were also performed. RESULTS: Ten of 15 horses with pastern dermatitis had feathered pasterns. Dermatophilus congolensis was identified by RT-qPCR from one nonfeathered horse but none with feathered pasterns. Cytological evaluation identified bacteria in all horses but failed to identify organisms resembling D. congolensis in any horse. Four of 15 horses, all feathered, were positive for Chorioptes mites. Fungal culture was negative for dermatophytes in all horses. All test results were negative for the eight control horses. CONCLUSIONS AND CLINICAL IMPORTANCE: Dermatophilus congolensis was uncommonly associated with pastern dermatitis in horses in this population. However, chorioptic mange was commonly associated with pastern dermatitis in feathered horses and represented an important differential diagnosis for this clinical presentation.

PCR analysis of a prescription vegetarian diet and use in three dogs with cutaneous adverse food reactions.

BACKGROUND: Cutaneous adverse food reaction (CAFR) is diagnosed by performing an elimination diet trial utilizing prescription or home-cooked diets followed by provocative challenge. OBJECTIVES: To report findings of PCR analysis of a prescription vegetarian diet (RCV) for undeclared proteins of animal origin, as well as to describe its utilization for diagnosis and management of dogs suspected of having CAFR. ANIMALS: Three client-owned dogs. METHODS: PCR analysis of RCV for 11 mammalian species and poultry. In three dogs, clinical examination, cytology, aerobic culture (if indicated) and at least one elimination diet trial with RCV. RESULTS: In our case series, all dogs had a history of pruritus and recurrent pyoderma that resolved with infection control and an elimination diet trial. In cases 1 and 2, a diagnosis of CAFR was made following an elimination trial with RCV and provocative challenge. Case 3 had a previously confirmed diagnosis of CAFR and RCV was successfully used to maintain remission of CAFR-related signs. PCR testing of RCV was negative for 11 mammalian species and poultry. CONCLUSIONS AND CLINICAL IMPORTANCE: The RCV diet was found not to contain any undeclared mammalian or avian proteins. In this case series, the RCV was successfully used to diagnose and maintain three dogs with CAFR.

Lymphocytic Mural Folliculitis Resembling Epitheliotropic Lymphoma in Tigers ( Panthera tigris).

A striking form of lymphocytic mural folliculitis is described in 6 tigers ( Panthera tigris). Clinically, all tigers exhibited regionally extensive chronic, variably waxing and waning alopecia with minimal scaling and crusting most pronounced over the head, neck, and shoulders. More severely affected tigers exhibited marked hyperpigmentation and lichenification. Pruritus was not a feature. Tigers generally lacked signs of systemic illness and clinical pathology findings were unremarkable. Histologic examination of skin biopsies revealed infiltrative lymphocytic mural folliculitis extending the length of the hair follicle. Mild epidermal lymphocytic infiltrates were frequent. The surrounding dermis was histologically unremarkable in 4 of 6 tigers or associated with mild perifollicular and periadnexal mixed inflammation in 2 of 6 tigers. The cause of the mural folliculitis was not identified, and tigers responded poorly to immunomodulatory therapy. Lymphocytic mural folliculitis might be a nonspecific hypersensitivity reaction pattern in tigers, and care should be taken to differentiate this reaction pattern from epitheliotropic T-cell lymphoma.

Mycoplasma infection of the middle ear in three cats.

BACKGROUND: Mycoplasma spp. are commensal organisms found in association with the mucus membranes of all mammalian species and are implicated in bacterial infections of many different locations. Mycoplasma spp. as a primary pathogen associated with otitis media in cats has not been reported. OBJECTIVES: To describe three cats with Mycoplasma infection of the middle ear associated with various underlying disease processes. ANIMALS: Three client-owned cats. METHODS: Clinical examination, aerobic culture of the middle ear and computed tomography or magnetic resonance imaging of the skull. RESULTS: Mycoplasma spp. were grown on aerobic culture from the middle ear of three cats. In Case 1, concurrent neoplasia of the bulla was identified. Mycoplasma alone was cultured in Case 2 and Mycoplasma was grown in addition to Bordetella in Case 3. Case 1 was euthanized, Case 2 responded to Mycoplasma targeted therapy and Case 3 responded to Bordetella targeted therapy. CONCLUSIONS AND CLINICAL IMPORTANCE: Mycoplasma infections of the middle ear may be clinically important and require targeted treatment in some cases.

Use of mycophenolate mofetil to treat immune-mediated skin disease in 14 dogs - a retrospective evaluation.

BACKGROUND: Mycophenolate mofetil (MMF) is a lymphocytotoxic immunosuppressive agent used in human and companion animal medicine for the treatment of immune-mediated disease. Mycophenolate mofetil is reported to have reduced myelotoxicity and hepatotoxicity when compared to azathioprine. OBJECTIVES: It was hypothesized that treatment with MMF as a secondary agent with glucocorticoids would be effective in treating immune-mediated skin disease. In addition, adverse effects associated with the drug are reported. ANIMALS: Fourteen dogs from a hospital population diagnosed with immune-mediated skin disease. METHODS: A retrospective review of medical records from 2010 to 2015 was used to identify dogs with immune-mediated skin disease that were treated with MMF. RESULTS: All dogs were treated with MMF (mean dose 14.7 mg/kg twice daily) in conjunction with glucocorticoids. Ten of 14 cases showed positive results, with complete remission in eight cases and partial remission in two cases. Mean time to remission was 5.7 weeks. Therapy was discontinued in one case (perianal fistula) due to lack of response. Adverse events were noted in six cases and included diarrhoea (n = 6), haematochezia (n = 2), vomiting (n = 3) and papilloma formation (n = 1). Therapy was discontinued in two cases with diarrhoea. Mycophenolate mofetil was discontinued in an additional case because of a diagnosis of neoplasia. All other adverse events were self-limiting or easily medically managed. No hepatotoxicity or bone marrow suppression was noted. CONCLUSION: This study supports the use of MMF as a second-line immunotherapeutic in immune-mediated skin disease in dogs.

Identification of canine papillomavirus by PCR in Greyhound dogs.

BACKGROUND: Corns are hard protuberances that occur on the digital footpads of Greyhound dogs. The cause of these lesions is unknown and there is little information about them in the veterinary literature. We received anecdotal examples of dog to dog spread of corns suggesting an infectious cause. The aim of this study was to determine if papillomavirus (PV) is associated with Greyhound corns. METHODS: We examined four corns from two unrelated adult Greyhound dogs that resided in Florida and Washington, respectively, for PV by PCR. The samples were obtained by owner coring of two lesions from one dog and laser removal of two lesions from the other dog. Total nucleic acid was extracted and DNA was amplified using two PCR primer sets that have been shown to amplify a broad range of PVs from humans and animals: FAP59/ FAP64 and MY11/ MY09. The DNA sequences were compared with all sequences in GenBank. Formalin-fixed, paraffin-embedded tissue from the footpads of four dogs with other inflammatory dermatoses were also examined. RESULTS: PV DNA was amplified from all four corn lesions, while no PV DNA was amplified from other tissues. Comparison of the 444-bp sequences amplified by the MY11/ MY09 primers identified two different PVs. One showed 96% nucleotide sequence similarity with the L1 gene of canine PV type 12. The other showed 78% similarity to canine PV type 16 and, therefore, represents a novel PV. In one of the corns, infection by two of the identified PVs was found. DISCUSSION: These results suggest PV infection could be involved in the pathogenesis of corns in Greyhound dogs.

RT-qPCR for the diagnosis of dermatophilosis in horses.

BACKGROUND: Dermatophilus congolensis causes a crusting dermatitis that affects horses. Diagnosis requires the identification of the organism with cytological evaluation of crust samples. This method can lack sensitivity in chronic cases. HYPOTHESIS/OBJECTIVES: To develop a probe-based real time quantitative polymerase chain reaction (RT-qPCR) test to assist with the diagnosis of dermatophilosis in horses. ANIMALS: Twenty six privately owned horses and seven horses from a research colony were used. METHODS: Crust samples, collected from 14 horses with suspected dermatophilosis and 12 horses with crusting skin disease not characteristic of dermatophilosis, were evaluated by cytological evaluation and RT-qPCR; the latter was also performed on hair samples collected from seven healthy horses. RESULTS: Cytological evaluation revealed organisms consistent with Dermatophilus congolensis from nine horses with suspected dermatophilosis, with only a few organisms seen from five samples. Cytological evaluation of all other crusts was negative for Dermatophilus. Other bacterial organisms were detected on cytological evaluation from 15 samples. RT-qPCR for Dermatophilus was positive from 11 crusts, whereas all other samples were negative. Two samples were cytologically negative but RT-qPCR positive for Dermatophilus. No samples were cytologically positive but RT-qPCR negative for Dermatophilus. CONCLUSION: Results of this study show that RT-qPCR may be a more sensitive and easier method than cytological evaluation for the diagnosis of dermatophilosis in horses.

Erythema multiforme associated with zonisamide in a dog.

This report describes a dog that developed erythema multiforme in temporal association with administration of the sulphonamide-based anticonvulsant drug zonisamide. Similar adverse drug reactions have been associated with sulphonamide antimicrobial drugs. Caution should be exercised when prescribing this medication for dogs with known hypersensitivity to sulphonamides.

Dorsal black skin necrosis in a Vietnamese pot-bellied pig.

BACKGROUND: Thermal burns are an uncommon cause of injury in large animals. CASE REPORT: A 10-month-old pet female black and white Vietnamese pot-bellied pig presented to the emergency service with fever and erythematous to purpuric skin lesions affecting the intermandibular space and hocks. One week prior to the emergency visit, she had appeared restless and in pain. Two weeks following the emergency visit, she again presented to the large animal clinic with sloughing of the pigmented skin on her head, face, dorsal and lateral trunk sparing the nonpigmented skin and pigmented ears. The affected skin constituted ~40% of her total skin. Histopathological findings for affected skin included full-thickness epidermal and partial to full-thickness dermal coagulative necrosis with follicular epithelial mineralization, while that from normal-appearing pigmented skin was within normal limits. A culture from a skin biopsy yielded meticillin-resistant Staphylococcus aureus (ST-72). Treatments included oral antibiotics, pain management, hyperbaric oxygen therapy and general anaesthesia to facilitate debridement. Healthy skin was often present when the necrotic skin was debrided, although in some areas the necrosis extended into the underlying fat. Complications that occurred during rehabilitation included intense pruritus that resulted in self-trauma and the formation of a nasal fistula, which was later surgically corrected. CONCLUSIONS AND CLINICAL IMPORTANCE: Cases of dorsal thermal necrosis in pot-bellied pigs are uncommon in the literature. Based on the clinical presentation and lack of another identifying cause, the lesions were attributed to a sun-induced thermal burn.

PCR amplification and DNA sequence identification of an unusual morphological form of Demodex cati in a cat.

BACKGROUND: Molecular characterization of Demodex mites is being used to identify mite species in dogs. This technique is now being applied to cat Demodex species, allowing for better characterization of the mites. HYPOTHESIS/OBJECTIVES: Molecular diagnostics will clarify the existence of diverse Demodex mites identified morphologically. ANIMALS: A cat with generalized demodicosis secondary to chronic steroid treatment for erythroid dysplasia. METHODS: Skin scrapings demonstrated large numbers of follicular mites consistent with Demodex cati as well as a morphologically different Demodex mite with a blunted abdomen. The 16S rRNA DNA was amplified by PCR, sequenced and compared with available Demodex sequences, including Demodex cati, Demodex gatoi and an unnamed Demodex sp. RESULTS: A single PCR product was obtained, the DNA sequence of which was an exact match with D. cati. CONCLUSIONS AND CLINICAL IMPORTANCE: The shorter unnamed mite was not a different species in this case, but a different morphological form of D. cati. This report demonstrates the utility of molecular diagnostics to clarify the identity of mites that differ morphologically.

Effects of butorphanol versus dexmedetomidine sedation on intradermal allergen and histamine responses in dogs with atopic dermatitis.

BACKGROUND: Sedation is commonly used during intradermal testing (IDT). Morphine and its derivatives have long been avoided because of their histamine-releasing effects. HYPOTHESIS/OBJECTIVES: Butorphanol, an opioid agonist/antagonist, will not adversely affect IDT in dogs. ANIMALS: Ten client-owned dogs diagnosed with atopic dermatitis. METHODS: Dogs were randomized to be sedated with butorphanol (0.4 mg/kg) or dexmedetomidine (5 µg/kg). Routine IDT along with intradermal injections of various dilutions of histamine were performed on the lateral thorax, followed 7 days later by the alternative sedative and IDT on the opposite side. The injection sites were subjectively scored and objectively measured by one investigator, blinded to the sedatives, and compared between groups. RESULTS: When the mean wheal diameters from the objective measurements of all antigens, including saline and histamine dilutions, were compared, butorphanol was associated with significantly smaller reactions than dexmedetomidine (P = 0.0001). There was a high level of agreement between sedatives when positive reactions subjectively scored as ≥3+ were compared (κ = 0.91). When mean wheal diameters of histamine at concentrations of 1:100,000, 1:400,000, 1:1,600,000 and 1:6,400,000 were compared, there were no significant differences between sedative types. Moreover, the percentage agreement when comparing subjective interpretation of all histamine dilutions between sedations was high (κ = 0.90). However, there was only 69% agreement beyond chance when objective and subjective interpretations of all antigens were compared between sedative groups. CONCLUSIONS: Although butorphanol resulted in significantly smaller wheal size in comparison to dexmedetomidine, it did not affect the overall subjective interpretation of the results of IDT.

Treatment of alopecia X with medroxyprogesterone acetate.

BACKGROUND: Alopecia X is a common cause of noninflammatory alopecia in Pomeranian dogs. In the past, treatment with growth hormone injections resulted in hair regrowth in many individuals. Progesterone can induce mammary-derived growth hormone and is used to treat dogs with congenital growth hormone deficiency. HYPOTHESIS/OBJECTIVES: To determine whether progesterone induces endogenous insulin-like growth factor-1 (IGF-1) and causes hair regrowth in dogs with alopecia X. ANIMALS: Eight neutered Pomeranian dogs with alopecia X for 1-2 years. METHODS: In part 1, two male and three female dogs received 5 mg/kg medroxyprogesterone acetate injected subcutaneously (s.c.) every 4 weeks for a total of four injections. In part 2, one male and two female dogs received 10 mg/kg medroxyprogesterone acetate injected s.c. every 4 weeks for four injections. Dogs were monitored monthly with physical examinations and complete blood counts, chemistry panels and urinalyses. In part 3, two coated Pomeranian dogs and two normal-coated small breed dogs received two s.c. injections of 10 mg/kg medroxyprogesterone acetate. Serum was saved from each visit for IGF-1 analysis. RESULTS: In part 1, two dogs had partial hair regrowth of ~40-60%. In part 2, one dog had partial hair regrowth and one dog had complete hair regrowth 2 months after completion of the study. Unlike the normal-coated dogs, whose IGF-1 concentrations increased, the IGF-1 concentrations in alopecic and coated Pomeranian dogs were low and remained unchanged. No adverse effects were noted. CONCLUSIONS AND CLINICAL IMPORTANCE: Results of this study showed that medroxyprogesterone injections resulted in partial hair regrowth in three and complete hair regrowth in one of eight Pomeranian dogs with alopecia X.