Cellular immunophenotyping of exfoliative dermatitis in canine leishmaniosis (Leishmania infantum)

Lymphocyte subsets, major histocompatibility complex (MHC)-II expressing cells and number of amastigotes in the epidermis and dermis were investigated immunohistochemically in 48 dogs with patent leishmaniosis, with or without exfoliative dermatitis (ED) to study the immunopathogenesis of this common cutaneous form of the disease. Skin biopsies were obtained and compared for ED sites (group A, n = 26), normal-appearing skin from the same animals (group B, n = 24), and leishmanial dogs not exhibiting ED (group C, n = 22), and normal controls (group D, n = 22). The CD3+, CD45RA+, CD4+, CD8+ (CD8a+), CD21+, and MHC-II+ cells and leishmania amastigotes were identified immunohistochemically and counted with the aid of an image analysis system. Pyogranulomatous to granulomatous dermatitis, expressed in various histopathological patterns, was noticed in all groups A and B and in half of group C dogs. In the epidermis, the low number of T-cells and their subsets did not differ significantly between groups A and B, but CD8+ outnumbered CD4+ lymphocytes in both groups. MHC-II+ expression on epidermal keratinocytes was intense in the skin with and without lesions from dogs with ED but not in group C dogs. CD3+, CD8+ and MHC-II+ cells were fewer in group C compared to group A and B dogs. In the dermis, CD3+ cells in group A animals were mainly represented by the CD8+. CD45RA+ and CD21+ cells were also seen in high numbers. MHC-II expression, potentially in lymphocytes, fibroblasts, dendritic cells, and macrophages was intense. The numbers of all cellular subpopulations in the dermis were significantly different between the groups, being highest in group A and lowest in group D. In sebaceous adenitis sites, CD4+ outnumbered CD8+ cells in contrast to the neighbouring dermis and the epidermis. The number of CD21+ and CD45RA+ cells was much lower in the inflamed sebaceous glands compared to the dermis. Finally, the number of amastigotes in the normal-appearing skin was significantly higher in the ED dogs (group B) than in those not exhibiting this cutaneous form of the disease (group C).     

Hypersensitivity skin testing of lambs infested with the biting louse (Bovicola ovis)

Abstract Cockle, a defect of lamb's pelts, has recently been shown to be associated with infestation of lambs with the louse Bovicoh ovis. The mechanisms by which infestation with the louse leads to cockle are not known, but immunological hypersensitivity has been suggested. The objectives of our work are to determine if lambs respond immunologically to lice and, if so, whether hypersensitivity occurs. Preliminary results are presented here.     

Combined effects of clenbuterol and various concentrations of protein on performance of broiler chickens

1. The effects of the beta-adrenergic agonist, clenbuterol (1 mg/kg diet) on the growth and muscle composition in female broiler chickens (14 to 32 d of age) fed on diets containing various concentrations of protein (220, 240 or 260 g protein/kg) were examined. 2. Body weight gain over the 18 d period increased linearly with increasing protein intake. The rate of gain was significantly higher in clenbuterol-treated chickens than in control birds. 3. Dietary clenbuterol increased thigh muscle weight and protein concentration of breast and thigh muscle, regardless of dietary protein content. Protein/DNA ratio in thigh muscle was enhanced by clenbuterol feeding, and the magnitude of difference of the ratio was higher in chickens fed on the 240 and 260 g CP/kg diets than in those fed the 220 g CP/kg diet. 4. It was concluded that clenbuterol-treated chickens require increased dietary protein to maintain maximal growth, and that increased protein consumption is an important factor in improving growth in clenbuterolfed broilers.     

Inter‐ and intra‐individual differences in serum copper and zinc concentrations after feeding different amounts of copper and zinc over two lactations

The influence of different copper and zinc contents in rations on blood serum concentrations was tested in a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute for Animal Health (FLI). A total of 60 German Holstein breed cows (38 first lactating and 22 second lactating cows) were tested. All animals received a diet based on maize‐ and grass silage ad libitum. The animals were divided into two groups with 30 cows each. Group A received concentrates supplemented with copper and zinc as recommended, whereas Group B was offered a concentrate with roughly double the amount of copper and zinc. Blood samples were taken several times during the lactation. The concentrations of copper and zinc in the serum were measured and correlations between trace element intake and their serum concentrations were calculated. The mean dry matter intake was significantly higher for cows in the second lactation (19.1 kg/day) than for cows in the first lactation (16.4 kg/day), whereas the DM‐intake was constant in the different feeding groups (17.3 and 17.4 kg/day). The correlation between feed intake in the first and the second lactation was r = 0.76. The copper concentration in the serum was not influenced by the different feedings (11.9 and 12.5 μmol/l), but high variations were found between the cows. The influence of the lactation number was not significant (12.1 and 12.4 μmol/l). In contrast to copper, the zinc concentration in the serum was significantly higher for Group B (14.0 μmol/l) than for Group A (12.2 μmol/l), respectively, for second lactating cows (13.8 μmol/l) in relation to 12.7 μmol/l for first lactating cows. The individual variation was also high as for copper. Neither the correlation between copper intake and copper serum concentration nor the correlation between zinc intake and zinc serum concentration was significant.     

Usefulness of aerobic microbial culture and cytologic evaluation of corneal specimens in the diagnosis of infectious ulcerative keratitis in animals

OBJECTIVE: To determine the diagnostic value of aerobic microbial culture and cytologic evaluation of corneal specimens in the diagnosis of infectious ulcerative keratitis (IUK). DESIGN: Prospective study. ANIMALS: 48 animals (26 dogs, 13 horses, 7 cats, 1 bird, and 1 llama) with corneal ulcers. PROCEDURE: Scrapings from corneal ulcers were examined cytologically. Corneal swab specimens were submitted for microbial culture. Animals were grouped according to whether they had been receiving antimicrobials at the time of admission. RESULTS: Of the 38 animals receiving antimicrobials, 19 had positive results for IUK on cytologic evaluation, 20 on microbial culture, and 26 on cytologic evaluation, microbial culture, or both. Of the 10 animals not receiving antimicrobials at the time of admission, 7 had positive results for IUK on cytologic evaluation, and 9 had positive results on microbial culture. In this group of 10 animals, additional animals with IUK were not identified on the basis of cytologic evaluation alone. When all 48 animals were considered irrespective of antimicrobial treatment, 26 and 29 had positive results for IUK on cytologic evaluation and microbial culture, respectively, whereas IUK was confirmed in 35 animals on the basis of cytologic evaluation, microbial culture results, or both. CONCLUSIONS AND CLINICAL RELEVANCE: Microbial culture and cytologic evaluation of corneal specimens maximizes identification of IUK, especially in animals receiving antimicrobial treatment. Because of serious consequences of untreated IUK, we recommend that both diagnostic tests be used to tailor treatment and reduce risk of vision impairment in animals.     

Pathological studies of cheek teeth apical infections in the horse: 4. Aetiopathological findings in 41 apically infected mandibular cheek teeth

Examination of 41 extracted, apically infected mandibular cheek teeth (CT) without obvious causes of infection included radiography, computerised axial tomography and decalcified and undecalcified histology. In CT with recent infections, some pulps remained viable, with proliferative soft and calcified tissue changes confined to the apex. With more advanced CT infections, occlusal pulpar exposure was sometimes present (in 34% of the 41 CT), some infected pulp chambers were filled with necrotic pulp or food, and extensive destructive or proliferative changes were present in the calcified apical tissues.No physical route of infection to the apex was found in 24 CT (59%) that consequently were believed to have anachoretic infections. Fractures involving pulps, including fissure fractures between the clinical crown and infected pulps, were found in eight (20%) CT. Some CT had vertical, full length periodontal destruction between the infected apex and the gingival margin that were believed to be the route of infection in four (19%) CT and dysplastic changes were believed to have caused one (2%) infections.     

Seasonal Variability in Stormwater Quality Treatment of Permeable Pavements Situated Over Heavy Clay and in a Cold Climate

Permeable pavements mitigate the impacts of urbanization on surface waters through pollutant load reduction, both by sequestration of pollutants and stormwater volume reduction through exfiltration. This study examined the non-winter water quality performance of two side-by-side permeable pavements in the Ohio snowbelt. The permeable interlocking concrete pavements were designed to drain impervious catchments 2.2 (large) and 7.2 (small) times larger than their surface area, were located over clay soils, and incorporated the internal water storage design feature. Nutrient reduction was similar to past studies—organic nitrogen and particulate phosphorus were removed through filtration and settling, while dissolved constituents received little treatment. Because of 16 and 32 % volume reductions in the small and large installations, respectively, nutrient loads were often significantly reduced but generally by less than 50 %. Aluminum, calcium, iron, magnesium, lead, chloride, and total suspended solids (TSS) concentrations and loads often increased after passing through the permeable pavements; effluent TSS loads were three- to five-fold higher than influent TSS loads. This was apparently due to seasonal release of clay- and silt-sized particles from the soils underlying the permeable pavement and inversely related to elapsed time since winter. The application of de-icing salt is thought to have caused deflocculation of the underlying soils, allowing particulates to exit with stormwater as it discharged from the underdrain of the permeable pavements. By autumn, both permeable pavements discharged metals and TSS concentrations similar to others in the literature, suggesting the de-icing effects lasted 3–6 months post-winter. Sodium may substantially affect the performance of permeable pavements following winter de-icing salt application, particularly when 2:1 clay minerals, such as vermiculites and smectites, predominate.