In vitro and in vivo effects of lufenuron on dermatophytes isolated from cases of canine and feline dermatophytoses

Lufenuron is a benzyl-urea phenol compound that inhibits chitin synthesis and is used as an insecticide. Its efficacy in the therapy of dermatophytosis in dogs and cats was evaluated in several clinical studies, with contradictory results. We assessed the in vitro susceptibility of dermatophytes isolated from dogs and cats to lufenuron, and the clinical response of skin lesions to the drug. Dermatophyte cultures isolated from clinical cases were exposed to lufenuron by three different methods: direct application and application of whole blood or subcutaneous tissue samples obtained from a lufenuron-treated healthy dog. No inhibition of dermatophyte growth was observed in any of the samples after 1 week of incubation. Eight dogs and six cats with skin lesions were included in the in vivo survey. Results indicated that six of seven skin lesions that were diagnosed as being caused by dermatophytes did not respond to lufenuron whereas six of seven skin lesions that were not caused by dermatophytes improved. We concluded that lufenuron, in the way it was administered in this study, had no inhibitory activity on dermatophytes in vitro or in vivo and its clinical use as an anti-fungal agent is questionable. An immunomodulatory effect of the drug is, however, possible.     

P‐13 Dermatophytosis in domestic cats: treatment with lufenuron

Preliminary studies showed that lufenuron inhibits chitin synthesis, a dermatophyte cell wall constituent, and may be effective in the treatment of dermatophytosis. Our purpose was to evaluate the efficacy of lufenuron in the treatment of feline dermatophytosis. Forty‐six cats (Persians and mixed‐breed cats from 1‐month to 4‐years old) naturally infected with Microsporumcanis were included in this study. Fifteen cats were treated isolated in cages in the veterinary hospital and 31 were treated in their home environment (some with access to the outdoors). Dermatophyte skin lesions were seen in 29 animals while 17 other cats were asymptomatic carriers. Wood's lamp, direct microscopic examination of hairs, fungal culture and skin biopsies were used for the diagnosis. Affected cats and all in‐contact animals received lufenuron at a dose of 120 mg/kg every 21 days for four treatments. Of the 29 symptomatic cats treated with lufenuron, 70% recovered within 21 days and 28% within 42 days of initiation of therapy. One cat had only partial recovery and another was euthanized. Negative fungal culture was recorded only after the fourth dose of lufenuron in 98% of affected cats and 100% of asymptomatic carriers. There was no difference in clinical response to lufenuron between the cats treated in their home environment and those treated in the veterinary hospital. Side effects were not observed, thus the drug proved to be safe and effective for the treatment of dermatophytosis. Funding: Novartis.     

Dermatophytes from skin lesions of domestic animals in Nsukka,Enugu State,Nigeria

Background – Dermatophytes are well‐recognized cutaneous fungi with public health implications. In Nigeria, several studies have been carried out on dermatophytosis in humans; however, data on dermatophytes in animals are lacking. Objectives – This study was conducted to determine the occurrence and species of dermatophytes in skin lesions in domestic animals in Nsukka Agricultural Zone of Enugu State, Nigeria. Animals – Forty‐six domestic animals (dogs, goats, sheep and pigs) presented for sale in the local markets in the study area and with suspected lesions of dermatophytosis were used for the study. Methods – Plucked hairs and epidermal scales from the skin lesions of affected animals were inoculated on Sabouraud dextrose agar slants containing 0.05 mg/mL of chloramphenicol and 0.5 mg/mL of cycloheximide. Inoculated slants were incubated at room temperature (27°C) for up to 4 weeks and examined at 2–3 day intervals for fungal growth. Laboratory identification of the fungal isolates was based on their colonial, microscopic and biochemical characteristics. Results – Of the 46 animals with suspected lesions of dermatophytosis, six (13.0%) were positive for a dermatophyte, and the following dermatophytes were identified: Microsporum gypseum, two of 12 sheep; Microsporum audouinii, one of 16 dogs; Trichophyton mentagrophytes, one of 16 dogs and one of 12 sheep; and Trichophyton schoenleinii, one of 13 goats. Conclusions and clinical importance – Anthropophilic dermatophytes are among the fungal agents associated with dermatophytosis in animals in Nsukka Agricultural Zone. These dermatophytes could constitute health risks to humans in contact with the animals.     

Use of lufenuron for treating fungal infections of dogs and cats: 297 cases (1997-1999)

OBJECTIVE: To evaluate use of lufenuron for treating cutaneous fungal infections in dogs and cats. DESIGN: Retrospective study. ANIMALS: 156 dogs and 201 cats with dermatophytosis or superficial dermatomycoses. PROCEDURE: Medical records were reviewed for dogs and cats that had been treated for dermatophytosis or other fungal infections by administration of lufenuron and 18 dogs and 42 cats that were not treated and served as a control group. RESULTS: Dogs were treated once by oral administration of lufenuron tablets at doses ranging from 54.2 to 68.3 mg/kg (24.6 to 31.0 mg/lb) of body weight. Samples of skin, scrapings, and hair were obtained daily from 14 dogs with dermatophytosis; mean durations from time of treatment to time of negative fungal culture results and resolution of gross lesions were 14.5 and 20.75 days, respectively. In all treated dogs, gross lesions resolved within approximately 21 days. Cats were treated once by oral administration of lufenuron suspension in doses ranging from 51.2 to 266 mg/kg (23.3 to 120.9 mg/lb). Samples were obtained daily from 23 cats; mean durations from time of treatment to time of negative fungal culture results and resolution of gross lesions were 8.3 and 12 days, respectively. Time to resolution of lesions in most untreated control animals was approximately 90 days. Adverse effects of treatment were not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study suggest that lufenuron provides an effective, convenient, and rapid method for treating fungal infections in dogs and cats.     

FC‐42 Sarcoptic mange epidemic in a cat population

Worldwide, sarcoptic mange in cats is seldom reported, and then only in sporadic individual cases. We describe an epidemic in a household with a dog and 25 cats. From September 2002, the dog was repeatedly treated with ivermectin for sarcoptic mange. The diagnosis was confirmed by skin scrapings. Fifteen months later, cats from the same household were diagnosed with severe sarcoptic mange. Twenty‐one of the cats were euthanized and necropsies were performed. Skin samples were taken from all cats from different body sites for histology, and skin scrapings were examined for ectoparasites. Samples for bacterial and dermatophyte culture were taken from six cats. Smears for cytology were made from lesions on four cats with severe mange. Sera from 21 cats and the dog were analysed for specific antibodies to Sarcoptesscabiei. Molecular characterizations of six individual mites were done. Large numbers of S.scabiei were isolated from the infected skin of most of the cats. Two‐thirds of the cats showed skin lesions compatible with chronic sarcoptic mange. Macroscopically, internal organs exhibited no obvious pathology. Yeast organisms and coccoid bacteria were found in the smears; penicillinase‐negative Staphylococcus aureus was isolated from all samples and Malassezia pachydermatis was identified from four cats. Sarcoptes scabiei was seen histologically in all cats showing chronic skin lesions. No other ectoparasites were found. All analysed cats had specific antibodies against S. scabiei. Twenty‐one cats tested negatively for FeLV and FIV. The mites had DNA sequences identical to S. scabiei from naturally infected dogs and Swedish wildlife. Funding: Self‐funded.     

FC‐1 Comparative efficacy of lufenuron and itraconazole in a guinea pig model of cutaneous Microsporum canis

During the last few years, reports have appeared claiming that lufenuron diminished or even cured dermatophyte infections in cats and dogs. As these observations have a rather anecdotal character leading to some ambiguity in the literature, it was decided to test lufenuron in a generally accepted animal model for dermatomycotic infection. The test was carried out in guinea pigs artificially infected with Microsporum canis on scarified dorsal skin and orally treated with lufenuron (Program?). The efficacy of up to five doses of 80 mg/kg was assessed 7 and 14 days after the start of treatment. All animals failed to show any improvement in skin lesions as compared to the vehicle‐only treated animals. Clinical symptoms taken into account were scaling, crust formation, erythema, and exudation. Neither the number of treatments (one or five) nor the dose range (40 or 80 mg/kg) made any difference. Itraconazole, tested earlier under identical circumstances, resulted in a clear and consistent improvement at day 7 of the infection at a dose of 15 mg/kg, given either in one dose or spread over several days. The absence of antimycotic activity of lufenuron in this established animal model constitutes a significant element in the discussion on the antifungal potency of lufenuron and supports the fact that there is, as yet, no evidence that benzoylphenyl urea derivative compounds have an effect on chitin synthesis in fungi. Funding: J&J Pharmaceutical Research and Development, Janssen Animal Health.     

P-15 Identification of Malassezia spp. isolated from a cat and cattle, including a new species, M. nana

Preliminary studies showed that lufenuron inhibits chitin synthesis, a dermatophyte cell wall constituent, and may be effective in the treatment of dermatophytosis. Our purpose was to evaluate the efficacy of lufenuron in the treatment of feline dermatophytosis. Forty-six cats (Persians and mixed-breed cats from 1-month to 4-years old) naturally infected with Microsporum canis were included in this study. Fifteen cats were treated isolated in cages in the veterinary hospital and 31 were treated in their home environment (some with access to the outdoors). Dermatophyte skin lesions were seen in 29 animals while 17 other cats were asymptomatic carriers. Wood's lamp, direct microscopic examination of hairs, fungal culture and skin biopsies were used for the diagnosis. Affected cats and all in-contact animals received lufenuron at a dose of 120 mg/kg every 21 days for four treatments. Of the 29 symptomatic cats treated with lufenuron, 70% recovered within 21 days and 28% within 42 days of initiation of therapy. One cat had only partial recovery and another was euthanized. Negative fungal culture was recorded only after the fourth dose of lufenuron in 98% of affected cats and 100% of asymptomatic carriers. There was no difference in clinical response to lufenuron between the cats treated in their home environment and those treated in the veterinary hospital. Side effects were not observed, thus the drug proved to be safe and effective for the treatment of dermatophytosis.
Funding: Novartis.     

Ultrasonographic Percutaneous Anatomy of the Atlanto‐Occipital Region and Indirect Ultrasound‐Guided Cisternal Puncture in the Dog and the Cat

Cisternal puncture in dogs and cats is commonly carried out. This article describes the percutaneous ultrasound anatomy of the cisternal region in the dog and the cat and an indirect technique for ultrasound‐guided cisternal puncture. Ultrasound images obtained ex vivo and in vivo were compared with anatomic sections and used to identify the landmarks for ultrasound‐guided cisternal puncture. The ultrasound‐guided procedure was established in cadavers and then applied in vivo in seven dogs and two cats. The anatomic landmarks for the ultrasound‐guided puncture are the cisterna magna, the spinal cord, the two occipital condyles on transverse images, the external occipital crest and the dorsal arch of the first cervical vertebra on longitudinal images. Using these ultrasound anatomic landmarks, an indirect ultrasound‐guided technique for cisternal puncture is applicable in the dog and the cat.     

Usefulness of cefovecin disk‐diffusion test for predicting mecA gene‐containing strains of Staphylococcus pseudintermedius and clinical efficacy of cefovecin in dogs with superficial pyoderma

Background –  Cefovecin has been widely used to treat skin infections in dogs. The relationship of the cefovecin disk‐diffusion test results to the presence of the mecA gene and the clinical efficacy of cefovecin have not been fully evaluated. Hypothesis/Objectives –  To determine the usefulness of an in vitro cefovecin disk‐diffusion test in predicting the presence of the mecA gene in Staphylococcus pseudintermedius, as well as the in vivo efficacy of cefovecin therapy in dogs with superficial pyoderma. Methods –  Twenty‐six S. pseudintermedius strains isolated from 22 dogs with pyoderma were used. In vitro disk‐diffusion test results of cefovecin were compared with agar‐dilution test results, the presence of the mecA gene, and the improvement in clinical scores of dogs with superficial pyoderma at 14 days post treatment. Results –  There was a significant linear correlation (r = ?0.83) between the diameter of the obvious zone of inhibition by disk diffusion and the minimal inhibitory concentration for cefovecin (P < 0.0001). Receiver operating characteristic analysis revealed that zone diameters between 25 and 27 mm exhibited better sensitivity (92.9%) and specificity (100.0%) for detection of strains carrying the mecA gene. The mean improvement in clinical scores in dogs carrying cefovecin‐resistant strains was significantly lower than in dogs carrying cefovecin‐susceptible strains (P < 0.01). Conclusions and clinical importance –  The cefovecin disk‐diffusion test with a cut‐off value estimated in this study was valuable for predicting mecA gene carriage in S. pseudintermedius, as well as the in vivo efficacy of cefovecin therapy in dogs with superficial pyoderma caused by S. pseudintermedius.     

Orbital abscess bacterial isolates and in vitro antimicrobial susceptibility patterns in dogs and cats

Objective To determine bacterial populations, in vitro antimicrobial susceptibility patterns, and sources of microorganisms for dogs and cats with orbital abscess. Animals studied In total, 34 dogs and 7 cats with orbital abscess participated in the study. Procedure Medical records of dogs and cats with a clinical diagnosis of orbital abscess, confirmed by cytologic or histopathologic evaluation of orbital specimens, were reviewed from the years 1990 to 2007. Animal signalment, presumptive source of microorganisms and mechanism of orbital introduction, bacterial isolates, and aerobic bacterial in vitro antimicrobial susceptibility test results were recorded. Percentages of susceptible aerobic bacterial isolates were compared among antimicrobials. Results Twenty dogs and five cats had positive culture results. The most frequent bacterial genera isolated from dogs were Staphylococcus, Escherichia, Bacteroides, Clostridium and Pasteurella. The most frequent bacterial genera isolated from cats were Pasteurella and Bacteroides. Aerobic bacterial isolates from dogs had the highest percentage of susceptibility to amikacin, ceftiofur, gentamicin, imipenem, ticarcillin and trimethoprim–sulfamethoxazole. Aerobic bacterial isolates from dogs had the lowest percentage of susceptibility to ampicillin, clindamycin, erythromycin and penicillin. Antimicrobial resistance was uncommon among feline aerobic bacterial isolates. The most commonly identified routes of orbital bacteria introduction were extension from adjacent anatomical structures, penetrating exogenous trauma, and foreign bodies. Conclusions Mixed aerobic and anaerobic bacterial infections of the orbit occur commonly in dogs and cats. On the basis of aerobic and anaerobic bacterial isolates and in vitro susceptibility testing of aerobic bacterial isolates, cephalosporins, extended‐spectrum penicillins, potentiated‐penicillins and carbapenems are recommended for initial antimicrobial therapy of orbital abscess in dogs and cats.     

Isolation of dermatophytes from dogs and cats with suspected dermatophytosis in Western Turkey

The aim of this study was to determine the species of dermatophytes isolated from dogs and cats and their prevalence in the two big provinces of Western Turkey. A total of 362 animals (198 dogs and 164 cats) with skin lesions (alopecia and desquamation) were examined from March 2006 to February 2008. Of the 362 samples examined, 52 (14.4%) were positive for fungal elements by direct microscopic examination, and 70 (19.3%) were culture positive for dermatophytes. The isolation rates of dermatophyte species from dogs and cats were 18.7% and 20.1%, respectively. Microsporum canis (57.1%) was the most common species isolated from dogs and cats. The prevalence of Trichophyton mentagrophytes was five-fold greater in dogs than in cats (odds ratio=5.226; CI=1.152-23.696). No association was detected between prevalence of infection and provinces, and also sex of dogs and cats. The only risk factor found to be significantly associated with infection was age. Dogs and cats younger than one year of age showed a statistically significant higher prevalence of dermatophytes than other age groups (P<0.05). The isolation rate of dermatophytes was relatively high in the spring and winter for dogs, and in the spring, summer and autumn for cats. However, the association of season and prevalence was found not to be significant.     

Molecular characterization of community‐associated methicillin‐resistant Staphylococcus aureus from pet dogs

Community‐associated methicillin‐resistant Staphylococcus aureus (MRSA) is a serious public health concern and in Australia, one that disproportionately affects Aboriginal people. Paralleling MRSA in human medicine, methicillin‐resistant S. pseudintermedius (MRSP) is an increasingly prevalent pathogen in veterinary medicine. We aimed to characterize the carriage of MRSA and MRSP in dogs and cats from predominantly Aboriginal communities in a very remote region of New South Wales (NSW), Australia. Pets (303 dogs and 80 cats) were recruited from six communities in western NSW. Three swabs were collected from each animal (anterior nares, oropharynx and perineum) and from skin lesions or wounds (if present) and cultured on selective media for methicillin‐resistant staphylococci. Human host‐adapted community‐associated MRSA representing four multilocus sequence types (ST1‐IV, ST5‐IV, ST72‐IV, ST93‐IV) were isolated from eight dogs (prevalence 2.6%, 95% confidence interval 1.3%–5.1%). Two ST5‐IV isolates from a single dog were phenotypically trimethoprim‐resistant, harbouring trimethoprim‐resistant gene dfrG within the SCCmec type IVo mobile genetic element. MRSA was not isolated from any cats and MRSP was not isolated from any dogs or cats. This study estimated a high prevalence of human host‐adapted community‐associated MRSA carriage in dogs despite an absence of MRSP. This suggests MRSA carried by dogs in remote NSW originate from human hosts. The cycle of transmission between people, dogs and common environmental sources warrants further investigation. To our knowledge, this is the first report of trimethoprim‐resistant ST5‐IV in eastern Australia and the first report of trimethoprim‐resistant ST5‐IV from a dog.     

WHOLE BODY COMPUTED TOMOGRAPHIC CHARACTERISTICS OF SKELETAL AND CARDIAC MUSCULAR METASTATIC NEOPLASIA IN DOGS AND CATS

Muscular metastatic neoplasia has been reported to be rare in domestic animals, however previous studies were based primarily on necropsy findings. The purpose of this retrospective study was to describe whole body computed tomography (CT) characteristics of confirmed muscular metastases in a cohort of dogs and cats presented for oncology evaluation. Medical records of 1201 oncology patients were reviewed. Included animals underwent pre and postcontrast whole body CT, and CT‐guided tru‐cut biopsy or fine needle aspiration of one or more metastatic lesions. Twenty‐one dogs and six cats met inclusion criteria, representing 2.08% of all canine oncology patients and 3.1% of all feline oncology patients. Mean age was 9.6 years. Postcontrast CT characteristics included well‐demarcated, oval‐to‐round lesions with varying enhancement patterns: ring enhancing (n = 16), heterogeneously enhancing (n = 8), or homogeneously enhancing (n = 5). Five animals showed concurrent and varying nodular patterns. In seven cases (five dogs and two cats), one single muscular nodule was observed. In 20 cases, two or more lesions were observed. In two cases, cardiac hypodense nodules were observed in the postcontrast CT, while appearing isodense in the precontrast study. Necropsy confirmed neoplasia in both of them. Locations of muscular metastases included epaxial/paraspinal muscles of the cervical, thoracic, and lumbar spine (n = 18), superficial muscles of the thoracic wall (n = 13), scapular/shoulder region (n = 3), hind limb (n = 3), and abdominal wall muscles (n = 1). Findings supported the use of pre and postcontrast whole body CT for oncologic staging in dogs and cats, especially for primary tumors characterized by a high metastatic rate.     

Ringworm in dogs and cats

Ringworm is an uncommon disease of dogs, but cats, especially the longhaired breeds, are more frequently infected. Of the several dermatophytes involved, Microsporum canis causes 94 per cent of ringworm in cats and 65 per cent in dogs. This species is highly contagious for man but the true incidence of human infection is unknown. Ringworm caused by M canis usually responds readily to treatment, but when the infection establishes in a colony of cats, eradication can be difficult and expensive. Other forms of ringworm in dogs and cats are caused by dermatophytes acquired from wild animals, mainly small rodents such as mice and voles. This is an uncommon and trivial disease of cats, but some infections in dogs can be remarkably persistent and difficult to resolve.     

Clinical signs, imaging features, neuropathology, and outcome in cats and dogs with central nervous system cryptococcosis from California

Background: Cryptococcus spp. is a fungal pathogen with a predilection for the central nervous system (CNS). Objectives: To compare the clinical, advanced imaging, and neuropathologic findings in dogs and cats with CNS cryptococcosis, and to evaluate outcome of treatment in these animals. Animals: Twenty‐six cats and 21 dogs with CNS cryptococcosis. Methods: Medical records were reviewed for clinical findings and results of CNS imaging. Archived cerebrospinal fluid and CNS tissue specimens were reviewed for pathology. Findings in cats were compared with those in dogs and the effects of variables on survival were determined by survival curve analysis. Results: When present, pain was localized to the cervical region in dogs and was generalized or localized to the thoracolumbar spine or pelvic limbs in cats. Magnetic resonance imaging (MRI) findings were variable but correlated with CNS histopathological findings of meningitis, meningitis with gelatinous pseudocyst formation, and granulomatous mass lesions. Peripherally enhancing brain lesions were seen only in cats. Histopathologically, the inflammatory response was milder in cats compared with dogs. Remissions of ≥1 year occurred in 32% of treated animals. Altered mentation was associated with negative outcome. Glucocorticoid use after diagnosis was associated with improved survival in the first 10 days. Conclusions and Clinical Importance: Lesions seen on MRI reflected neuropathological findings and were similar to those reported in human patients. The immune response to infection may differ between cats and dogs, or relate to the infecting cryptococcal species. Long‐term (>6 month median survival time) survival may be possible in animals surviving ≥4 days after diagnosis.     

FC‐14 Clonality studies of feline cutaneous lymphocytosis

A previous study described cutaneous lymphocytosis (CL) in 23 cats. The process resembles cutaneous pseudolymphoma in humans, a heterogeneous group of benign reactive proliferations of well‐differentiated lymphocytes in the skin of humans. Morphological and immunophenotypic characteristics do not offer reliable criteria to accurately predict the clinical outcome of feline CL or pseudolymphoma in humans. Presence of clonal cell populations is more consistent with a neoplastic process. In a previous study, feline CL lesions (20 cats) were evaluated for clonality using PCR, and only two cats had monoclonal T‐cell populations. Because false‐negative results may occur, the purpose of this study was to repeat the PCR using a revised primer set based on analysis of additional feline T‐cell receptor γ (TCRγ) sequences. DNA was isolated from 29 skin lesions and six internal organs of 20 cats. DNA integrity was assessed by glyceraldehyde‐3‐phosphate dehydrogenase PCR. Polymerase chain reaction clonality was performed using the revised primer set specific for feline TCRγ, and duplicate samples were evaluated. The PCR products were assessed by heteroduplex analysis. Clonal rearrangement of TCRγ was detected in 14 cats (24 of 35 tissues: 21 of 29 skin lesions and three of six internal organs); eight of these cats are still alive and six were euthanized. Monoclonal populations were seen in three of five cats that had involvement of internal organs. These findings indicate that feline CL is best considered as a slowly progressive process which may be reactive, but often evolves into a low‐grade indolent lymphoma. Funding: George H. Muller Fund for Research in Dermatology.     

Heterogeneity of Staphylococcus pseudintermedius isolates from atopic and healthy dogs

Staphylococcus pseudintermedius is part of the normal canine flora but frequently causes pyoderma in canine atopic dermatitis (AD). This study aimed to determine whether particular S. pseudintermedius strains were associated with AD and/or pyoderma. Ninety‐six S. pseudintermedius isolates from the ear, nares, perineum and lesions of 21 atopic and 16 healthy dogs were lysed with proteinase K and digested with 40 U SmaI. Restriction products were separated using pulsed‐field gel electrophoresis (PFGE) with an Oxford S. aureus control and lambda‐ladder DNA concatomer markers. A dendrogram was constructed by the unweighted pair group method. All isolates showed a ≥56% similarity coefficient. Nine distinct PFGE clusters were identified, as follows: five from both atopic and healthy dogs; three from atopic dogs only; and one from healthy dogs only. Nine clusters were isolated from the nares, eight from the perineum, five from the ears and six from pyoderma lesions. There were no significant differences in the frequency of isolation from atopic or healthy skin, body sites or infected lesions for any of the clusters. Two of six healthy dogs and 18 of 20 atopic dogs with multiple isolates had closely related isolates (less than three band differences) at more than one sampling site. Isolates from pyoderma lesions were closely related to at least one mucosal isolate in 11 of 16 dogs. Staphylococcus pseudintermedius isolates appear to be heterogeneous, and colonization or infection of atopic skin was not associated with any particular strain or cluster of strains.     

Induction of feline flea allergy dermatitis and the incidence and histopathological characteristics of concurrent indolent lip ulcers

The objectives of this study were to characterize the role of intermittent vs. continual flea exposure in the development of flea allergy dermatitis (FAD) in cats, assess the accuracy of intradermal skin testing (IDST) and in vitro testing, and document the incidence and histopathological features of indolent lip ulcers. Ten flea‐naive cats were divided into two groups. One group received intermittent flea exposure for 120 days. Thereafter, both groups of cats received continuous flea exposure for 120 days. In vitro testing for flea salivary antibody and IDST utilizing both whole flea antigen and flea salivary antigen were performed. Eight of 10 cats developed clinical signs of FAD within 3 months and five of these eight cats developed lip ulcers which where characterized histopathologically by ulceration with predominantly neutrophilic inflammation and surface bacterial colonization. There was no association between the presence or absence of clinical signs and positive IDST or in vitro results, and no difference in the development of clinical signs was noted between the two groups of cats.     

Evaluation of the comparative efficacy of selamectin against flea (Ctenocephalides felis felis) infestations on dogs and cats in simulated home environments

The comparative efficacy of monthly administration of selamectin or lufenuron against Ctenocephalides felis felis on dogs and cats was evaluated over a 5-month period in flea-infested environments. Twenty-four dogs and 32 cats were randomly allocated to receiving a topical treatment with selamectin or an oral administration of tablets containing lufenuron/milbemycin oxime (for dogs) or lufenuron only (for cats). Each product was administered in accordance with the manufacturer's label recommendations. Eight dogs and four cats served as untreated sentinels. Treatments were administered on days 0, 30, 60, 90, and 120. Each animal received an application of 100 fleas on days -28 and -21, and then weekly applications of 20 fleas from days 91 through 147. Flea comb counts were performed on day -6, and every 2 weeks after day 0. From day 29 (dogs) or day 44 (cats) to day 150, geometric mean flea counts for selamectin were < or =0.4. Mean flea counts for animals assigned to treatment with selamectin were significantly lower (P=0.0001) than for animals assigned to treatment with lufenuron at all assessments after day 0.     

Skin lipid profiling in normal and seborrhoeic shih tzu dogs

Background – Seborrhoea is a clinical condition resulting in excessive lipid and/or scale on the skin and is a common and important skin disease of dogs. However, there is little information on the skin surface lipid composition of dogs with seborrhoea. Hypothesis/Objectives – To compare skin surface lipid profiles in normal and seborrhoeic shih tzu dogs. Methods – Fourteen client‐owned dogs (seven seborrhoeic and seven normal) were investigated. Lipids in sebaceous glands (SGs) were extracted from homogenized tissues of SG hyperplasia. Surface lipid was collected by tape stripping [stratum corneum (SC)‐enriched fraction] and acetone‐wetted cotton swab (acetone‐extracted fraction). Lipids in SGs, SC‐enriched fractions and acetone‐extracted fractions were evaluated by high‐performance thin‐layer chromatography. Results – Lipids in SGs mainly consisted of cholesterol esters, wax esters and triglycerides, whereas lipids in the SC‐enriched fraction mainly consisted of ceramides. The acetone‐extracted fraction contained a mixture of lipid classes recognized in SG‐ and SC‐enriched fractions. In seborrhoeic dogs, concentrations of wax esters and triglycerides in the acetone‐extracted fraction were significantly higher than in control dogs (P = 0.0285). Amounts of total ceramides (in micrograms) per milligram of SC were not significantly different between the two groups (P = 0.5204). Interestingly, two unknown ceramide fractions, which accounted for 20% of the total ceramides, were recognized exclusively in seborrhoeic dogs. Conclusions and clinical importance – These results provide evidence that the skin surface lipid profiles are altered in shih tzu dogs with seborrhoea.