Diascopy and histopathological evaluation of nonblanching erythematous dermatoses in dogs.

BACKGROUND: Diascopy is a point-of-care diagnostic test used to differentiate skin erythema due to vascular dilation from haemorrhage. In the veterinary literature, only a handful of diseases have been described to be associated with a negative (nonblanching) diascopy result, and histological investigation of haemorrhage has been inconsistent. OBJECTIVES: Retrospective study to undertake a histopathological investigation of canine, nonblanching erythematous dermatoses for the presence or absence of haemorrhage and vascular changes. MATERIALS AND METHODS: Skin biopsies from dogs presented with moderate-to-severe nonblanching erythema were evaluated histologically. Additionally, clinical data about each patient were analysed. RESULTS: Twenty cases were identified with nonblanching erythema. Diagnoses included vasculopathy (n = 6), canine eosinophilic dermatitis (n = 3), cutaneous epitheliotropic T-cell lymphoma (n = 2), and one case each of sterile granuloma and pyogranuloma syndrome, German shepherd dog pyoderma, multiple mast cell tumours, haemangiosarcoma, exfoliative cutaneous lupus erythematosus, canine leishmaniosis with sebaceous adenitis, sebaceous adenitis with concurrent dermatophytosis, calcinosis cutis and canine atopic dermatitis with insect-bite reaction. One or more vascular changes were present in all 20 cases and included perivascular oedema, endothelial swelling and neutrophilic infiltration of vessel walls. Haemorrhage was identified in 17 of 20 cases (85%). Three cases without dermal haemorrhage were calcinosis cutis, sebaceous adenitis with dermatophytosis and canine atopic dermatitis with insect-bite reaction. CONCLUSIONS AND CLINICAL RELEVANCE: Negative diascopy was associated with haemorrhage and vascular pathological findings in the majority of cases, yet not all. Haemorrhage was identified histologically in all diseases previously reported as nonblanching as well as in a few additional diseases.

Cutaneous microRNA expression in healthy Labrador and Golden retrievers and retrievers with allergic and inflammatory skin diseases.

BACKGROUND: MicroRNAs (miRNA) are short, single-stranded RNA molecules that regulate gene expression in a post-transcriptional manner. Their expression is proposed to be tissue-specific and alterations in miRNA expression have been detected in many diseases. OBJECTIVE: To compare miRNA expression in the skin of healthy Labrador and golden retrievers, and those with allergic and nonallergic dermatitis. METHODS AND MATERIALS: Formalin-fixed and paraffin-embedded (FFPE) skin specimens from seven healthy Labrador and golden retrievers, and seven dogs with allergic skin disease were collected. A further mixed nonallergic inflammation group consisted of samples from five dogs with fungal infection, demodicosis and mast cell tumours. Total RNA was extracted and miRNA primer assays for 18 target miRNAs (miR-142, miR-363, miR-18b, miR-451, miR-146a, miR-124, miR-409, miR-193b, miR-223, miR-215, miR-155, miR-423a, miR-143, miR-1839, miR-21, miR-34b, miR-146b and miR-202) were performed, with RNU6-2 and SNORD95 as miRNAs for normalisation. The selection of miRNAs for investigation was based on reported data and a pilot study evaluating miRNA extraction from FFPE tissue specimens. RESULTS: In the two dogs with mast cell tumours, miRNA expression was undetermined for most miRNAs, so both were excluded from analysis. Although there were differences in the miRNA expression between healthy and inflamed skin, allergic and nonallergic inflammation showed similar expression patterns. CONCLUSION AND CLINICAL RELEVANCE: Although the number of included dogs was small, based on this study, none of the evaluated miRNAs allowed differentiation of allergic dermatitis from other inflammatory skin diseases in retriever dogs.

Interferon therapies in small animals.

Interferons (IFNs) are cytokines that play an important role in the immune response of animals and humans. A number of studies reviewed here have evaluated the use of human, canine and feline IFNs as treatments for infectious, inflammatory and neoplastic disease in dogs and cats. Recombinant canine IFN-γ is deemed an efficacious therapy for canine atopic dermatitis. Recombinant feline IFN-ω is effective against canine parvoviral enteritis and has also been recommended for canine atopic dermatitis. Based on limited evidence, recombinant canine IFN-α could be a topical treatment option for dogs with gingivitis and keratoconjunctivitis sicca. Conclusive evidence is lacking for other diseases and large randomised controlled trials are needed before IFNs can be recommended for other indications.

A case series of canine cutaneous inverted papilloma with one case showing evidence of recurrence.

BACKGROUND: This article describes a case of multiple, recurrent, cutaneous inverted papillomas (CIPs) in a German shepherd dog, combined with a retrospective follow-up assessment of eight cases. METHODS: A 3-year-old, black, female German shepherd dog presented with four rapidly growing, alopecic, domed, hyperpigmented, shiny nodules, compatible with CIP. The dog was managed for pruritus, associated with atopic dermatitis, with long-term prednisolone therapy and this therapy was continued after the surgical excision. Twelve months after the initial presentation the dog was represented for two new CIP lesions, coinciding with an increased dosage of prednisolone during an allergic flare-up period. RESULTS: Histopathological evaluation was conducted on both the original and subsequent lesions from the case with recurrence. Eight cases of CIP, based on histopathological findings, were identified retrospectively from the authors' diagnostic pathology service over the previous two years. All nine cases had lesions that exhibited varying degrees of inverted epithelial hyperplasia, multiple, endophytic, papillary epidermal projections, a cup-shaped base with central hyperkeratosis and active viral pathological findings (koilocytes). The submitting veterinarians were contacted and follow-up regarding recurrence and concurrent medications was obtained. CONCLUSIONS AND CLINICAL IMPORTANCE: CIP is uncommonly reported, typically as a single lesion with no previous reports of recurrence, although one group of dogs with severe combined immunodeficiency developed invasive malignancies. In seven of eight retrospective cases no recurrence of CIP was recorded. The authors speculate that the recurrence in the German shepherd dog may have been associated with chronic (although low-dose) glucocorticoid administration.

Recurrent polyp formation with Candida tropicalis infection and otitis in a dog.

To describe a case of a recurrent Candida tropicalis otitis externa, media and interna in a dog with an ear polyp. A 9-year-old Irish Setter was presented with 2 episodes of otitis sinistra, left-sided vestibular syndrome and Horner syndrome 7 months apart. At the first episode a benign ear polyp was extracted and Candida tropicalis cultured from the left middle ear. The neurological signs disappeared within 7 days, the Candida infection was more difficult to treat. Seven months later, a polyp was found in the ear again and cytology was consistent with Candida tropicalis. A unilateral left total ear canal ablation with lateral bulla osteotomy was performed and a middle ear culture confirmed Candida tropicalis. Treatment led to resolution of clinical signs. Candida tropicalis, an emerging pathogen, should be considered in cases of recurrent yeast otitis and may be difficult to treat.

Serum concentrations of IL-31 in dogs with nonpruritic mast cell tumours or lymphoma.

BACKGROUND: The aim of this study was to compare serum interleukin (IL)-31 concentrations in dogs with lymphoma and mast cell tumours (MCT) without pruritus to those of healthy dogs. HYPOTHESIS/OBJECTIVES: To determine if IL-31 plays a role in tumour pathogenesis and if IL-31 could be a biological marker for disease progression. ANIMALS: Forty-eight healthy dogs and 36 dogs with neoplasia [multicentric lymphoma (14), MCT (15) and cutaneous lymphoma (7)] were included in the study. METHODS AND MATERIALS: Dogs with neoplasia were assigned to three different groups. Group 1 consisted of patients with multicentric lymphoma, which were diagnosed by cytological, histopathological and clonality investigations. Thoracic radiographs, ultrasound examination of the abdominal cavity, and fine-needle aspirates from liver and spleen were used to determine the lymphoma stage Patients with cutaneous lymphoma, diagnosed by cytological and histopathological findings, were included in Group 2. Patients with MCT, diagnosed by cytological and histopathological findings, were included in Group 3. Serum was frozen at -80ºC before measuring the concentration of IL-31 via a Simoa ultra-sensitive, fully automated two-step immunoassay. RESULTS: Serum concentrations of IL-31, regardless of the disease and its staging, were within the normal range in all patients; there was no difference between any of the different tumour groups and healthy dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: IL-31 is not likely to be involved in the pathogenesis of canine MCT or lymphoma without pruritus.

Critically appraised topic on adverse food reactions of companion animals (9): time to flare of cutaneous signs after a dietary challenge in dogs and cats with food allergies.

BACKGROUND: At this time, elimination diets followed by oral food challenges (OFCs) represent the "gold standard" for diagnosing skin-manifesting food allergies (FA) in dogs and cats. Regrettably, there is no clear consensus on how long one should wait for clinical signs to flare after an OFC before diagnosing or ruling-out a FA in a dog or a cat. RESULTS: We searched two databases on October 23, 2019 to look for specific information on the time for a flare of clinical signs to occur during OFCs after elimination diets in dogs and cats with skin-manifesting FAs. Altogether, we reviewed the study results of nine papers that included 234 dogs and four articles containing data from 83 cats. As multiple OFCs could be done in the same patient and not all animals included were subjected to an OFC, we were able to compile 315 and 72 times to flare (TTF) after an OFC in dogs and cats, respectively. When regrouping all cases together, about 9% of dogs and 27% of cats exhibited a flare of clinical signs in the first day after an OFC; 21% of dogs and 29% of cats had such relapse by the end of the second day. The time needed for 50 and 90% of dogs to exhibit a deterioration of clinical signs (TTF50 and TTF90) was 5 and 14, respectively; in cats, these times were 4 and 7 days, respectively. By 14 days after an OFC, nearly all food-allergic patients from both species had had a relapse of clinical signs. These results are limited by the likely under-reporting of flares that occur on the first day immediately following an OFC, the time in which IgE-mediated acute allergic reactions typically develop. CONCLUSION: Veterinary clinicians performing an OFC need to wait for 14 and 7 days for more than 90% of dogs and cats with a skin-manifesting FA to have a flare of clinical signs, respectively.

Is there a correlation between canine adult-onset demodicosis and other diseases?

Demodicosis is frequently seen in small animal practice. In older dogs, it is often associated with immunosuppression and immunosuppressive diseases. The aim of this study was to evaluate a larger number of dogs with adult-onset demodicosis (AOD) at the veterinary teaching hospitals of the University of Sydney/Australia and the University of Munich/Germany. Breed predispositions were compared with the two control populations. Of more than 20 000 dogs and 15 000 in each respective hospital population, 54 dogs in Munich and 68 dogs in Sydney were diagnosed with AOD at a mean age of 8 years. Breed predispositions were seen for West Highland White Terriers in Munich (p<0.0001) and Maltese Terriers and Shih Tzus in Sydney (p<0.01). Concurrent diseases were confirmed in approximately 40% of the dogs both in Munich and Sydney. A significant association was only found between AOD and hyperglucocorticoidism, hypothyroidism and (in Munich) leishmaniosis. Neoplastic diseases were not significantly more common in dogs with demodicosis than in the total population at both locations (p>0.05). Consequently, dogs with AOD should be evaluated for concurrent hyperglucocorticoidism and hypothyroidism, and, in areas of the world where this is prevalent, also for leishmaniosis.

Dermatophytosis in dogs and cats - an update. / Dermatophytose bei Hund und Katze ­ ein Update.

Dermatophytosis is a cutaneous infection, caused by several types of keratophilic fungi (dermatophytes). It represents a serious and common contagious skin disease in dogs and cats. The significance of this disease for pet owners is based on the zoonotic potential. The prevalence varies with climate and local dermatophyte infestation. The most common infection in dogs and cats are caused by the genera Microsporum (M.), Nannizzia (N.) or Trichophyton (T.). The aim of this article is to summarise novel taxonomy, diagnosis, and treatment recommendations as well as the recently revised recommendations of the World Association of Veterinary Dermatology.

Retrospective analysis of pleural effusion in cats.

OBJECTIVES: Pleural effusion is a common presenting cause for feline patients in small animal practice. The objectives of this study were to identify possible correlations between the aetiology of effusion and clinical and laboratory findings. METHODS: In this retrospective study of 306 cats diagnosed with pleural effusion of established aetiology, cats were divided into six major groups: cardiac disease (CD), feline infectious peritonitis (FIP), neoplasia, pyothorax, chylothorax and miscellaneous. Clinical, laboratory and radiographic parameters were compared between groups. RESULTS: CD was the most common aetiology (35.3%), followed by neoplasia (30.7%), pyothorax (8.8%), FIP (8.5%), chylothorax (4.6%) and miscellaneous diseases (3.7%). In 26 (8.5%) cats, more than one underlying disease was diagnosed as a possible aetiology for pleural effusion. Cats with FIP were significantly younger than those with CD (P <0.001) and neoplasia (P <0.001). Cats with CD were presented with a significantly lower body temperature compared with cats with FIP (P = 0.022). Cats with CD had significantly higher serum alanine aminotransferase activity compared with all other cats (FIP and pyothorax, P <0.001; neoplasia and chylothorax, P = 0.02) and serum alkaline phosphatase activity compared with the pyothorax (P <0.001) and FIP groups (P = 0.04), and significantly lower protein concentrations (FIP, pyothorax and neoplasia, P <0.001; chylothorax, P = 0.04) and nucleated cell counts in the effusion than all other groups (pyothorax and neoplasia, P <0.001; chylothorax, P = 0.02; FIP, P = 0.04). The glucose level in the effusion of cats with pyothorax was significantly lower than glucose levels in patients with CD, neoplasia and chylothorax (P <0.001). Of 249 cats with a follow-up of at least 10 days, 55.8% died or were euthanased during that time. CONCLUSIONS AND RELEVANCE: CD and neoplasia were the most common causes for feline pleural effusion. Age, liver enzymes, as well as cell count, protein and glucose levels in the effusion can aid in the investigation of underlying aetiologies.

[Targeting the skin - erythema multiforme in dogs and cats]. / Die Haut als Zielscheibe ­ Erythema multiforme bei Hund und Katze.

This review article will describe the complex nature of erythema multiforme in dogs and cats. The disease pattern will be illustrated in terms of etiology, pathogenesis, clinical signs, diagnostics and therapy. Erythema multiforme is a rare, immune-mediated skin disorder with an acute specific reaction pattern of skin and mucous membranes against different underlying causes. Reported triggering factors include drugs, food ingredients and neoplasias, but viral or bacterial infections and vaccine reactions were also identified. In over 20% of the cases the cause cannot be identified. The German Shepherd dog and Pembroke Welsh Corgi seem to be predisposed. Erythematous macules, slightly elevated and peripherally spreading papules as well as circular to arciform patterns were described frequently in the dog. Wheals, plaques, vesicles and bullae that develop into ulcers, are also seen. Frequently affected areas in the dog are the ventrum, mucocutaneous junctions, mouth, pinnae and foot pads. Histopathological findings include single cell necrosis in all layers of the epidermis with lymphocytic satellitosis and a cell-poor interface dermatitis. Elimination of the causative factors and concurrent symptomatic therapy are recommended. The prognosis varies from guarded to fair, depending on the underlying cause, presenting clinical signs and response to therapy.

Seasonal leukotrichia in a German shepherd dog. A case report. / Saisonale Leukotrichie bei einem Deutschen Schäferhund. Ein Fallbericht.

Leukotrichia can be caused by a variety of metabolic and inflammatory diseases. Canine alopecia areata is a rare multifactorial benign non-scarring alopecia. This case report describes a seasonally recurrent leukotrichia associated with alopecia areata in a German shepherd dog. Important differential diagnoses were ruled out and histopathology finally confirmed the diagnosis of alopecia areata. Topical tacrolimus and hydrocortisone aceponate were ineffective. The cause for the seasonal character in this case remained undetermined.

Urinary tract infections in cats. Prevalence of comorbidities and bacterial species, and determination of antimicrobial susceptibility to commonly used antimicrobial agents. / Bakterielle Harnwegsinfektionen bei Katzen. Prävalenz prädisponierender Erkrankungen und bakterieller Isolate sowie Ermittlung der antimikrobiellen Resistenz gegenüber häufig eingesetzten Antibiotika.

OBJECTIVE: To investigate the prevalence of comorbidities (CM) in cats with urinary tract infections (UTIs), as well as the prevalence of bacterial species in cats with different CM and their antimicrobial susceptibility to the commonly used antibacterial agents doxycycline, trimethoprim-sulfamethoxazole (TMS), amoxicillin-clavulanic acid (AMC), cephalothin, and enrofloxacin. MATERIAL AND METHODS: A retrospective analysis of cats with positive urine cultures in the years 2003 to 2009 was performed. Cats were assigned to one of four groups: cats with systemic comorbidities (sCM), cats with indwelling urinary catheters (iUC), cats with local comorbidities (lCM), or cats without CM. To evaluate the potential effectivity of the antibiotics the antibacterial impact factors were calculated. RESULTS: A total of 194 cats with 219 isolates were included in the study. In 78.4% (152/194) of cats, a CM was identified; 49.5% had a sCM and 28.9% (56/194) had an iUC or a lCM. Cats with sCM were significantly older than cats in all other groups, and the proportion of female animals was higher in cats with sCM than in cats with iUC or lCM. More than half of the cats with sCM did not show clinical signs of lower urinary tract disease. The most commonly isolated bacteria species were Escherichia (E.) coli, Streptococcus spp., Staphylococcus spp., and Enterococcus spp. with a significantly higher proportion of E. coli isolates in cats with sCM and significantly higher proportions of Streptococcus and Staphylococcus spp. isolates in cats with iUC and other lCM. According to the antimicrobial impact factors bacterial isolates in cats with any CM were most likely susceptible to AMC and TMS. Isolates from cats with iUC and lCM had a lower likelihood to be susceptible to the tested antimicrobials than cats with sCM and cats without CM. CONCLUSION AND CLINICAL RELEVANCE: Relevant comorbidities for bacterial urinary tract infection were identified in the majority of cats in the present study. Cats with sCM often do not show clinical signs of lower urinary tract disease. AMC and TMS were the antimicrobial agents with the highest antimicrobial impact factor in this population of cats.

Sampling sites for detection of feline herpesvirus-1, feline calicivirus and Chlamydia felis in cats with feline upper respiratory tract disease.

OBJECTIVES: Feline herpesvirus-1 (FHV-1), feline calicivirus (FCV) and Chlamydia felis are involved in feline upper respiratory tract disease (FURTD). Clinical signs caused by these agents can overlap, and the involvement of certain pathogens is often unpredictable. The objectives of this study were to compare detection rates of FHV-1, FCV and C felis at different sampling sites, and to investigate the correlation between positive test results and clinical signs in cats with FURTD. METHODS: Swabs were taken from the nose, pharynx, tongue and conjunctiva of 104 cats with signs of FURTD. Real-time PCR was performed on all samples for the detection of FHV-1, FCV and C felis. RESULTS: Infectious agents were identified in 93 (89.4%) cats. Of these, 55.8% were positive for FHV-1, 50.0% for FCV and 35.6% for C felis. FCV was found more frequently in the oropharynx (92.3% of FCV-positive cats) and on the tongue (90.4%) than the conjunctiva (38.5%) (P <0.001). There was no significant difference between the four sampling sites for the detection of FHV-1 and C felis. If nasal samples had also been taken, 94.9% of FHV-1-positive cats, 96.2% of FCV-positive cats and 81.1% of C felis-positive cats would have been detected. CONCLUSIONS AND RELEVANCE: The oropharynx can be recommended as the preferred single sampling site for the detection of FCV, FHV-1 and C felis if only one sample can be taken; however, taking samples at different sites significantly increases the detection rate for all pathogens studied. Interestingly, sampling from a site with FURTD-associated lesions did not increase the likelihood of detecting the infectious agents.

Nonthymoma-associated exfoliative dermatitis in 18 cats.

BACKGROUND: Exfoliative dermatitis has been described in cats as a paraneoplastic skin disease associated with thymoma. There are anecdotal reports of cases without thymoma, with various suspected aetiologies. HYPOTHESIS/OBJECTIVES: To identify common features, underlying causes, response to therapy and outcome of nonthymoma-associated exfoliative dermatitis in cats. METHODS: Retrospective analysis was carried out of cases presented to dermatology referral centres or cases submitted for histopathological examination. Detailed historical and clinical data were obtained and evaluated statistically. Histopathology was reviewed in a blinded fashion by three dermatopathologists, and PCR for herpesvirus was performed. RESULTS: Eighteen cats fulfilled all inclusion criteria. There was no sex, age or breed predisposition. All cats presented with severe generalized (77%) or multifocal exfoliation (23%); 12 cats were severely depressed. In all cats, thymoma was excluded radiographically and feline leukaemia virus tests were negative. Additional imaging procedures in 14 cats and postmortem examination in two cats did not detect neoplasia. Histopathology revealed interface dermatitis, mural interface folliculitis and sebaceous adenitis indistinguishable from findings in thymoma-associated cases. PCR for herpes DNA was negative. No aetiology was identified. Treatment in 12 cases consisted of immunosuppressive doses of corticosteroids and/or ciclosporin; one responded to antibiotics, one to shampoo, two went into spontaneous remission, and two did not receive any therapy and were euthanized. CONCLUSIONS AND CLINICAL IMPORTANCE: Nonthymoma-associated exfoliative dermatitis in cats is clinically and histopathologically indistinguishable from thymoma-associated cases. Most cases benefit from immunosuppressive therapy; therefore, an immunopathological response to an undefined trigger is suspected.

Gene expression in the skin of dogs sensitized to the house dust mite Dermatophagoides farinae.

Atopic dermatitis is a multifactorial allergic skin disease in humans and dogs. Genetic predisposition, immunologic hyperreactivity, a defective skin barrier, and environmental factors play a role in its pathogenesis. The aim of this study was to analyze gene expression in the skin of dogs sensitized to house dust mite antigens. Skin biopsy samples were collected from six sensitized and six nonsensitized Beagle dogs before and 6 hr and 24 hr after challenge using skin patches with allergen or saline as a negative control. Transcriptome analysis was performed by the use of DNA microarrays and expression of selected genes was validated by quantitative real-time RT-PCR. Expression data were compared between groups (unpaired design). After 24 hr, 597 differentially expressed genes were detected, 361 with higher and 226 with lower mRNA concentrations in allergen-treated skin of sensitized dogs compared with their saline-treated skin and compared with the control specimens. Functional annotation clustering and pathway- and co-citation analysis showed that the genes with increased expression were involved in inflammation, wound healing, and immune response. In contrast, genes with decreased expression in sensitized dogs were associated with differentiation and barrier function of the skin. Because the sensitized dogs did not show differences in the untreated skin compared with controls, inflammation after allergen patch test probably led to a decrease in the expression of genes important for barrier formation. Our results further confirm the similar pathophysiology of human and canine atopic dermatitis and revealed genes previously not known to be involved in canine atopic dermatitis.

Detection of feline Mycoplasma species in cats with feline asthma and chronic bronchitis.

Little is known about the aetiology of inflammatory lower airway disease in cats. The aim of this study was to investigate the role of Mycoplasma species in cats with feline asthma (FA) and chronic bronchitis (CB). The study population consisted of 17 cats with FA/CB, and 14 sick cats without clinical and historical signs of respiratory disease, which were euthanased for various other reasons. Nasal swabs, nasal lavage and bronchoalveolar lavage fluid (BALF) samples were taken from patients from both groups. Mycoplasma species culture with modified Hayflick agar and Mycoplasma polymerase chain reaction (PCR) were performed on all samples followed by sequencing of all Mycoplasma species-positive samples for differentiation of subspecies. PCR testing detected significantly more Mycoplasma species-positive BALF samples than Mycoplasma culture (P = 0.021). When cats with oropharyngeal contamination were excluded from comparison, the numbers of Mycoplasma species-positive BALF samples in the group with FA/CB (6/17) and the control group (4/9) were not significantly different (P = 0.6924). While all nasal samples of the cats with FA/CB were negative for Mycoplasma organisms, five samples in the control group (P = 0.041) were positive on PCR. Sequencing revealed Mycoplasma felis in all PCR-positive samples. Mycoplasma species can be detected in the lower airways of cats with FA/CB, as well as in the BALF of sick cats without respiratory signs. Further studies are warranted to investigate the possibility that Mycoplasma species represent commensals of the lower respiratory tract of cats.

Treatment of demodicosis in dogs: 2011 clinical practice guidelines.

BACKGROUND AND OBJECTIVES: These guidelines were written by an international group of specialists with the aim to provide veterinarians with current recommendations for the diagnosis and treatment of canine demodicosis. METHODS: Published studies of the various treatment options were reviewed and summarized. Where evidence in form of published studies was not available, expert consensus formed the base of the recommendations. RESULTS: Demodicosis can usually be diagnosed by deep skin scrapings or trichograms; in rare cases a skin biopsy may be needed for diagnosis. Immune suppression due to endoparasitism or malnutrition in young dogs and endocrine diseases, neoplasia and chemotherapy in older dogs are considered predisposing factors and should be diagnosed and treated to optimize the therapeutic outcome. Dogs with disease severity requiring parasiticidal therapy should not be bred. Secondary bacterial skin infections frequently complicate the disease and require topical and/or systemic antimicrobial therapy. There is good evidence for the efficacy of weekly amitraz rinses and daily oral macrocyclic lactones such as milbemycin oxime, ivermectin and moxidectin for the treatment of canine demodicosis. Weekly application of topical moxidectin can be useful in dogs with milder forms of the disease. There is some evidence for the efficacy of weekly or twice weekly subcutaneous or oral doramectin. Systemic macrocyclic lactones may cause neurological adverse effects in sensitive dogs, thus a gradual increase to the final therapeutic dose may be prudent (particularly in herding breeds). Treatment should be monitored with monthly skin scrapings and extended beyond clinical and microscopic cure to minimize recurrences.

Bovine besnoitiosis in Germany.

This paper reports a case of natural occurring bovine besnoitiosis in Germany. The skin lesions consisted of multifocal hypotrichosis and alopecia, lichenification, erythema and seborrhoea. Histopathologic findings revealed characteristic cysts of Besnoitia spp. The diagnosis was confirmed by serology and the species Besnoitia besnoiti was identified by polymerase chain reaction (PCR).

Cutaneous epitheliotropic T-cell lymphoma with dissemination to the liver in an eastern chipmunk (Tamias striatus).

Cutaneous epitheliotropic T-cell lymphoma with liver metastasis was diagnosed in a 10-year-old eastern chipmunk (Tamias striatus). Physical findings included intracutaneous swellings, ulcerated plaques and nodules, hypotrichosis and erythema of the skin. Fine needle aspiration from the skin lesions showed a population of large lymphocytes and lymphoblasts, and was helpful in establishing the diagnosis antemortem. The post-mortem examination revealed epitheliotropic lymphoma with liver metastasis. Immunohistochemistry proved the T-cell origin both in the liver and skin tumours. Electron microscopy did not reveal any viral particles within the tumour. To the authors' knowledge, this is the first case of lymphoma described in this species.