Spongiotic vesicular dermatitis as a cutaneous reaction pattern in seven horses

Over a 6-year period seven adult horses of different breeds and genders developed multifocal, exudative, oozing dermatitis characterized histologically by epidermal spongiotic vesicles and perivascular eosinophilic, neutrophilic and mixed mononuclear inflammation. Three horses were pruritic. Systemic disease was not noted. Two horses had a history of recurrent urticaria (hives) and one horse had nodules or welt-type lesions that progressed to exudative, oozing lesions. Interepithelial immunoglobulin (Ig)G was detected by avidin-biotin complex-peroxidase staining, but the pattern of staining was more consistent with epithelial oedema than specific IgG deposition associated with pemphigus. The exudative oozing lesions developed under circumstances suggesting that dermal oedema progressed to intracellular and intercellular epidermal oedema, which in turn progressed to the spongiotic vesicular epidermal lesions.     

Assessment of infectious organisms associated with chronic rhinosinusitis in cats

OBJECTIVE: To determine detection rates for feline herpesvirus type 1 (FHV-1), Mycoplasma spp, fungi, and bacteria in flush samples and biopsy specimens from the nasal cavities of cats with and without chronic rhinosinusitis (CRS). DESIGN: Prospective study. ANIMALS: 10 CRS-affected cats and 7 cats without signs of respiratory tract disease. PROCEDURES: Nasal flush samples and biopsy specimens were collected from all cats for bacterial (aerobic and anaerobic), fungal, and mycoplasmal cultures; additional biopsy specimens were collected for virus isolation and polymerase chain reaction (PCR) assay (to detect FHV-1 DNA). RESULTS: Aerobic bacteria were detected in flush samples from 5 of 7 control cats; culture of flush samples from CRS-affected cats yielded aerobic bacteria (9/10 cats), anaerobic bacteria (3/10), and Mycoplasma spp (2/10). No fungal organisms were isolated from any cat. Potential pathogens were isolated significantly more often from CRS-affected cats than from control cats. Bacterial culture of biopsy specimens yielded aerobic bacteria (2/7 control cats and 4/10 CRS-affected cats) and anaerobic bacteria (2/10 CRS-affected cats). Although FHV-1 was not detected in nasal biopsy specimens from control or CRS-affected cats, FHV-1 DNA was detected via PCR assay in specimens from 4 of 7 control cats and 3 of 10 CRS-affected cats. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with findings in control cats, anaerobic bacteria, Mycoplasma spp, and a variety of potentially pathogenic organisms were detected more commonly in samples from cats with CRS. In both groups, FHV-1 was detected via PCR assay as a nonviable organism or in noncultivable amounts.     

Locomotive disorders associated with sow mortality in Danish pig herds

Given the increase in sow mortality in Danish pig herds over the last 10 years, we have investigated the causes of spontaneous death and killing of sows, especially those due to locomotive disorders. A total of 265 culled sows (93 spontaneously dead sows and 172 killed sows) from 10 different herds were sent for complete necropsy, and grouped according to primary diagnoses. From 35 of these sows, tissue for histological evaluation and samples for bacteriological cultivation were also collected, and secondary diagnoses and body condition were recorded. The main causes for killing were related to the locomotive system (72%), arthritis (24%) and fractures (16%) being the most frequent lesions. The main causes of spontaneous death were related to the gastrointestinal system and spleen (45%) and the reproductive system (24%). Arthrosis was a secondary diagnosis in 88% of the killed sows and in 92.5% of the spontaneously dead sows. Arcanobacterium pyogenes was the main cause of arthritis. The killed sows had significantly lower body condition compared with spontaneously dead sows. The first two parities and the time around farrowing were associated with the highest mortality in both groups. Hopefully, these observations can guide breeding units attempting to monitor, control and reduce sow mortality.     

Radiographic features of two cases of feline proximal femoral dysplasia

Congenital or acquired feline femoral dysplasia have seldom been reported in the literature. This report describes two cases of femoral dysplasia involving the proximal epiphyses. Bilateral agenesis of the femoral head and neck (case 1) constituted an incidental finding during a post-traumatic radiographic examination, while right proximal femoral dysplasia (case 2) was observed during an orthopaedic examination for lameness. To the authors' knowledge, such imaging findings have not been reported before in cats.     

Risk factors associated with Neospora caninum abortion in Ontario Holstein dairy herds

The objective of this epidemiological study was to identify risk factors for Neospora caninum-related abortions in Ontario Holstein dairy herds. A total of 88 herds, consisting of 5080 cattle, and utilizing Dairy Herd Improvement (DHI) services, were divided into three groups. Case (n = 30) and first control (n = 31) herds were selected from 1998 and 1999 fetal abortion submissions to the Animal Health Laboratory, University of Guelph, that were histopathologically positive or negative, respectively, for N. caninum. A second control group (n = 27) was selected from multiple sources of herds sampled within the previous 4 years that had a low seroprevalence (<7%) to N. caninum. Between May and December 1999, all available cows on all farms, in parity one or greater, were blood sampled. The sera were then analyzed for antibody to N. caninum using a kinetic ELISA. A survey administered at the time of sampling recorded information on housing, animal species present, manure management, reproduction, biosecurity practices, wildlife observations, peri-parturient cow management, herd disease history and nutrition. Production and other herd parameters were obtained from DHI records. Logistic regression indicated that the following parameters were positively associated with a N. caninum abortion in a herd: the N. caninum herd seroprevalence (OR = 1.1), the total number of dogs on a farm (OR = 2.8), the frequency that dogs were observed defecating in mangers (OR = 2.8), the number of horses on a farm (OR = 3.1), the observed annual rate of retained fetal membranes (OR = 1.2) and the observed annual rate of cows returning to estrus after pregnancy confirmation (OR = 1.2). Factors negatively associated were the frequency of stray cats and wild canids observed on a farm (OR = 0.4 and OR = 0.7, respectively) and the housing of heifers on loafing packs (a housing pen divided into feed manger, scrape alley and bedded pack areas, OR = 0.1).     

Clinical evaluation of gemcitabine in dogs with spontaneously occurring malignancies

We conducted a clinical evaluation of gemcitabine in 19 dogs with spontaneously occurring malignancies. The principal objectives of this study were to characterize toxicity and seek preliminary evidence of antitumor activity of gemcitabine administered every 2 weeks (biweekly) as a 30-minute IV infusion. A total of 64 doses, ranging from 300 mg/m2 to 675 mg/m2, were administered during the initial 8-week evaluation period, and an additional 131 doses were administered during the extended evaluation period. The total cumulative dose for the 10 dogs receiving gemcitabine in the extended evaluation period ranged from 1,500 mg/m2 to 24,300 mg/m2. Clinical evidence of toxicity was minimal. Cumulative myelosuppression was not apparent. Unexplained retinal hemorrhages occurred in 1 dog. No complete or partial remissions were observed during the initial evaluation period; however, objective responses were observed in 2 dogs during the extended evaluation period. Gemcitabine is a promising new chemotherapeutic agent that can be used safely in dogs with cancer. Biweekly administration of doses of 675 mg/m2 IV results in minimal and acceptable toxicity.     

Diagnostic tests for small ruminant lentiviruses

Maedi visna virus and caprine arthritis encephalitis virus are closely related retroviruses that cause chronic inflammatory disease in small ruminants. The infections are characterised by insidious onset and slow progression. Diagnosis of infection is usually by serological testing. A variety of assays are available for this purpose, though the relative sensitivity and specificity of these assays has not been compared systematically. Here we review recent developments in laboratory diagnostic methods and their use in field diagnosis. The results suggest that a combination of ELISA and PCR might afford optimal detection of SRLV infection.     

Factors Affecting Fertility According to the Postpartum Period in Crossbred Dual-Purpose Suckling Cows in the Tropics

To determine the relationship between first service conception rate (FSC) and the postpartum period (PP), 6160 calvings from 2250 crossbred dual-purpose cows were analysed. The effects of breed predominance (BT: Bos taurus and BI: Bos indicus), season of service (dry, intermediate and humid), parity (1 or 2 and more), agroecological region (Sub-humid and Dry Tropical Forest) and milk production were studied. The postpartum period was grouped according to the calving–first service interval as G1 ≤ 60 days (n = 1889); G2 > 60 ≤ 90 days (n = 1436); G3 > 90 ≤ 120 days (n = 1030); and G4 > 120 days (n = 1805). Data were analysed by chi-squared test. The overall mean for FSC was 58.2% and was lower in G1 (p < 0.01). All PP showed a breed effect on FSC, with mean values of 61.6% and 53.3% for BI and BT, respectively. Season of service also affected FSC, which was significantly lower during the humid period: 51.2% versus 57.4% and 61.5% for the intermediate and dry periods (p < 0.01), respectively. Parity and environmental effects were not observed on FSC. Levels of milk yield did influence the FSC, which decreased from 66.7% and 61.0% for milk yields of < 1500 kg and between 1501 and 2000 kg to 46.0% in milk yields > 2000 kg (p < 0.01).