Twenty-nine dogs were included in a double-blinded, placebo-controlled, randomised trial and were orally supplemented for 10 weeks with either flax oil (200 mg/kg/day), eicosapentaenoic acid (50 mg/kg/day) and docosahexaenoic acid (35 mg/kg/day) in a commercial preparation, or mineral oil as a placebo. For each dog, clinical scores were determined based on a scoring system developed prior to the trial. Total omega-6 and omega-3 intake and the ratio of omega-6:omega-3 (omega-6:3) were calculated before and after the trial. The dogs' clinical scores improved in those supplemented with flax oil and the commercial preparation, but not in the placebo group. No correlation was identified between total fatty acid intake or omega-6:3 ratio and clinical scores. Based on the results of this study, the total intake of fatty acids or the omega-6:3 ratio do not seem to be the main factors in determining the clinical response.

The objectives of this multicentre study were to analyse and compare breed predispositions and lesion distributions of 552 dogs diagnosed with atopic dermatitis from five different dermatologic referral centres located in Australia, Germany (2) and the United States (2). Breeds were compared with the canine population in the respective locations. Breed predispositions varied from geographical site, although golden retrievers and German shepherd dogs were predisposed in three of five practices. Lesions were present most commonly on the paws (62%), ventrum (51%), ears (48%) and face (39%). Various breeds had specific site predilections. Based on this study, breed predispositions can vary greatly both between continents and also between different locations on the same continent. In addition, some breeds showed predispositions for certain body sites which also varied in some instances with the geographical location.

The purposes of this double‐blinded, randomized study were to determine the success rate of rush immunotherapy in canine atopic dermatitis and compare it to conventional immunotherapy, and to assess if rush immunotherapy leads to a quicker reduction in clinical signs than conventional immunotherapy. Twenty‐two atopic dogs diagnosed by history, physical examination and appropriate exclusion of differential diagnoses were included in the study. Offending allergens were identified with an intradermal test. All dogs were premedicated for 3 days with an antihistamine, and then hospitalized for 1 day. Injections with prepared treatment sets were administered every 30 min subcutaneously for 7 h; dogs were then discharged and continued on immunotherapy for 1 year. All dogs were evaluated monthly by their owners for 12 months, and by clinicians prior to therapy and after 3, 6, 9 and 12 months of therapy using a standardized scoring system to measure pruritus, lesions present and any concurrent medications given. Eleven dogs were treated with rush immunotherapy, and 11 dogs with conventional immunotherapy. Significant differences in mean pruritus, medication, lesion and total scores between groups were determined by use of a repeated‐measures ANOVA. Mean pruritus scores decreased from 13.5 to 6.7 (P = 0.0333) and from 13.9 to 10.3, medication scores from 23.6 to 10.6 (P = 0.0001) and from 14.1 to 13.6, lesion scores from 5.9 to 1.6 (P = 0.0001) and from 3.0 to 1.9, and total scores from 42 to 18.1 (P = 0.001) and from 30.6 to 21.5 in the rush immunotherapy group and in the conventional immunotherapy group, respectively. Using a Tukey–Kramer Multiple Comparison test, differences between the total scores at the beginning of the study and at the various time points reached significance after 3 months. An improvement of >50% in pruritus was noted in six of 11 dogs in the rush immunotherapy group and in five of 11 dogs in the conventional immunotherapy group; similar improvements in lesion scores and total scores were observed in dogs treated with rush immunotherapy (seven of 11 and five of 11 dogs, respectively) and in dogs treated with conventional immunotherapy (seven of 11 and four of 11 dogs, respectively). Based on these results, rush immunotherapy seems to be associated with a higher success rate than conventional immunotherapy, and improvement is typically seen within the first 6 months of therapy. Funding: Morris Animal Foundation.

The records of 15 horses with pemphigus foliaceus diagnosed on the basis of their history, clinical signs, histopathology and the exclusion of differential diagnoses were evaluated with respect to the age of onset, the clinical signs and the diagnostic tests used. There was no apparent breed predisposition. The horses' mean age was nine years, with a range from three months to 25.5 years, three were foals up to six months old and eight were nine years old or older. The most frequent lesions were scaling in 11, crusting in 10 and alopecia in 10, and they appeared most commonly on the face, neck and trunk, in 10 horses for each of these sites. The extremities were involved in nine of the horses, pruritus occurred in seven, and four of the horses had pustules. The clinical signs mostly corresponded with those described in previous reports, but signs of pain were not a prominent feature. Acantholytic cells were identified cytologically in four of six of the horses.

Canine toxic epidermal necrosis (TEN), a rare and life-threatening cutaneous drug reaction, traditionally has been described as full-thickness devitalization of the epidermis with minimal dermal inflammation; however, few reports detail the histologic findings. We characterize the clinical features and histologic variations of 3 canine TEN patients. Clinically, irregular erythematous and purpuric macules evolved into widespread and severely painful erosions. The number of eroded mucosae varied; however, periocular and perilabial mucocutaneous junctions frequently were affected. Thirteen of 17 biopsies were evaluated. Apoptosis at multiple epidermal levels was the most common pattern of epidermal necrosis (12/13 biopsies, 92%). In contrast, full-thickness coagulation necrosis was present less often (7/13 biopsies, 52%). Lymphocytic interface dermatitis was the predominant inflammatory pattern, and intraepidermal lymphocytes, along with fewer histiocytes, were present to some degree in all samples along with lymphocytic satellitosis of apoptotic keratinocytes. The sequence of changes points to lymphocyte-mediated keratinocyte apoptosis as an early step in lesion development with subsequent variation in progression to coagulation necrosis among patients. Histopathologic changes overlapped with those reported for erythema multiforme, in contrast to traditional histologic descriptions of canine TEN. A specific algorithm for assessment of drug causality in epidermal necrolysis (ALDEN) was applied for each patient; carprofen was associated with a probable score for causality in 1 dog. Clinicians should be encouraged to take multiple biopsies in TEN suspect cases as nearly 25% of all biopsies lacked epithelium and were not diagnostic.