Hereditary equine regional dermal asthenia ("hyperelastosis cutis") in 50 horses: clinical, histological, immunohistological and ultrastructural findings

Data on fifty horses with hereditary equine regional dermal asthenia (HERDA; "hyperelastosis cutis") were collected on clinical, histopathological, ultrastructural and immunohistological findings. All horses were Quarter horses or of Quarter horse ancestry. Pedigree evaluation strongly supported an autosomal recessive mode of inheritance. The most common lesions were seromas/haematomas, open wounds, sloughing skin, and loose, easily tented skin that did not return to its initial position. Definitive diagnosis could not be made via histopathology, although the presence of tightly grouped thin and shortened collagen fibres arranged in clusters in the deep dermis was suggestive of the disease. Trichrome, acid orcein-Giemsa and immunohistochemical stains for collagens I and III showed no consistent abnormalities compared to control horses; an increase in elastic fibres was not a consistent finding. Electron microscopy showed no abnormalities in the periodicity of the collagen bundles; neither orientation nor variation of cross-section diameter of the collagen fibrils differentiated control from affected horses. The diagnosis of HERDA relies on clinical presentation, but may be supported by suggestive (although not pathognomonic) histopathological lesions.     

Radiographic evaluation and treatment of feline dental resorptive lesions.

Many feline resorptive lesions are easily diagnosed by clinical oral examination, whereas others require dental radiographs. Radiographs can reveal the presence of resorption, and often the nature of the resorptive process as well. Removal of affected teeth when they cause discomfort, or of the portion of the tooth causing the discomfort, remains the only treatment that provides long-term resolution. Until we understand the etiology of the inciting causes and of the factors contributing to the progression of resorptive lesions, reliable prevention cannot be offered.     

Normal hematologic and biochemical values for prelaying greater sage grouse (Centrocercus urophasianus) and their influence on chick survival.

Declines in greater sage grouse (Centrocercus urophasianus) productivity and population numbers throughout their range demand a better understanding of how nutrition influences sage grouse populations. During March and April 1999-2001, blood samples were collected from 158 female (73 adult, 85 yearling), free-ranging, prelaying, greater sage grouse from an area in northwestern Nevada, USA, and southeastern Oregon, USA. These blood samples were evaluated to establish normal blood values for sage grouse and ascertain if certain blood parameters, as indices of nutrition, are useful for predicting if sage grouse hens would raise at least one chick to 1 August. Results of logistic regression indicated that three of six blood parameters analyzed--glucose, total plasma protein, and calcium: phosphorus ratio-affected the probability of a female sage grouse raising at least one chick to late summer. Ranking of the standardized estimates revealed that glucose and total plasma protein had the greatest impact on the likelihood of a female successfully raising chicks. Odds ratios indicated that a 1-unit increase in glucose (1 mg/dl) and plasma protein (0.1 g/dl) would result in a 4% and 113% positive increase, respectively, in the predicted odds of at least one chick surviving until 1 August. Odds ratios for calcium : phosphorus ratio revealed a 70% decline in the predicted odds of at least one chick surviving until 1 August if the level of this parameter increased one unit (e.g., 3:1 to 4:1). Based on these analyses, values of some blood parameters used as indices of nutrition, especially glucose, total plasma protein, and calcium : phosphorus ratio, can be successfully used to predict reproductive success of sage grouse. These parameters are not only indicative of the nutritional status of prelaying hens but may be associated with nutritional quality of the habitat and therefore have important management significance.     

Toll-like receptor expression in feline lymphoid tissues

Toll-like receptors (TLRs) are germline-encoded pattern recognition receptors (PRRs) that activate the innate immune system. While it is clear that TLRs are important in the immune response against pathogens, they may also be exploited by some pathogens. Our objective is to determine whether feline immunodeficiency virus (FIV) infection affects TLR expression or function thereby resulting in innate immune dysfunction. To this end, we cloned partial sequences for feline TLRs 1--3, 5--8, and developed real-time PCR assays to quantify feline TLRs 1--9. TLR expression was quantified in normal cat lymphoid tissues, purified lymphocyte subsets, and FIV-infected cell lines. Different expression patterns of TLRs were found in spleen, mesenteric lymph node, retropharyngeal lymph node, thymus, intestinal intraepithelial lymphocytes, and lamina propria lymphocytes. B lymphocytes, CD4+ T cells, and CD8+ T cells all expressed TLRs 2--5, 7--9; however, the relative levels of expression varied among lymphocyte phenotypes. Infection of cell lines with FIV resulted in altered TLR expression levels that differed depending on cell type. These results demonstrate that tissue distribution of TLRs is associated with the immunological role of a particular tissue, that lymphocytes may also express these 'innate immune' receptors, and that FIV infection can alter TLR expression.     

Failure to induce homologous immunity to Fasciola hepatica in sheep vaccinated with irradiated metacercariae

Vaccination of sheep with either 100 or 1000 γ-irradiated (2.5 krad) metacercariae of Fasciola hepatica, on two occasions six weeks apart, did not generate significant protection against intraruminal challenge with F. hepatica six weeks after the second vaccinating dose as measured by recovery of flukes from liver and bile ducts, twenty weeks after challenge. There was, however, a significant increase in the proportion of flukes retarded in the parenchyma of both vaccinated groups. The percentage of retarded flukes was positively correlated with the degree of liver damage and increased weight of the hepatic lymph nodes. It was not possible to determine if the retarded flukes were derived from the vaccine or challenge infections or both.Challenge infection of both vaccinated and unvaccinated sheep significantly increased the numbers of eosinophils and globule leucocytes in the parenchymal bile duct and the numbers of mast cells and globule leucocytes in the abdominal bile duct. In addition the numbers of eosinophils and globule leucocytes in the parenchymal bile duct were significantly correlated with the percentage of retarded flukes in both vaccinated groups. In the abdominal bile duct, only the numbers of eosinophils in the low level vaccination group were significantly correlated with fluke retardation.Vaccination did not protect against the pathogenic effects of challenge infection as measured by reduced packed cell volumes and weight gain.     

RADIOGRAPHIC BONE LOSS CORRELATIONS AND TECHNETIUM-99m-MDP BONE UPTAKE IN LIGATURE-INDUCED PERIODONTAL DISEASE IN THE BEAGLE

The goal of this study was to develop an animal model for the study of acute periodontal disease using silk ligatures in combination with a soft diet in eleven purebred beagle dogs. The silk ligatures were placed subgingivally on the mandible second and fourth premolar on one side of the mouth; the opposite side served as a control. Dogs were monitored during the 16–20 weeks of ligature placement, and for 48 weeks after ligature removal. Development of periodontal disease was evaluated by radiopharmaceutical uptake into bone, radiographic evidence of alveolar bone loss, attachment loss, gingival index and prostaglandin level. Bone loss occurred on the ligatured side during the ligature phase of the study. Radiopharmaceutical uptake was correlated with radiographic evidence of bone loss during the ligature phase. No significant bone loss occurred during the post-ligature phase. Progressive periodontal disease was induced during ligature placement. However, a chronic less aggressive form was not sustained by soft diet alone after ligature removal.     

Kinetic gait analysis of healthy dogs on two different surfaces

Objective— To determine the effects of 2 different, commonly used surfaces with different coefficients of friction on ground reaction forces in normal dogs.
Study Design— Prospective, observational, single cross-over study.
Animals— Dogs (n=10) with no gait abnormalities.
Methods— Dogs were acclimated to the force plate and 5 valid trials for each dog and each limb were recorded. Velocity and acceleration were tightly controlled. Each dog was tested on both surfaces sequentially in different sequences. Data analysis was done on peak vertical force, peak impulse, breaking and propulsion peak forces and impulses. Three-way repeated measures analysis of variance was used to separately evaluate the effect of floor type on force plate measures in fore and hind limbs, while controlling for side (left versus right) and experimental replicate. P -values<.05 were considered significant. Mean force and 95% confidence interval for the 6 variables analyzed for all limbs on each surface were calculated.
Results— There were no significant differences in ground reaction forces between the linoleum and the carpet surface for thoracic or pelvic limbs for all gait variables measured. There were no significant differences between each individual gait trial per dog between the right and left thoracic limbs trials nor differences between the right and left pelvic limb trials.
Conclusions— Normal dogs had no change in their ground reaction forces on linoleum and carpet surfaces.
Clinical Relevance— Kinetic results from multi-center or comparative trials will not be affected by use of either linoleum or carpet surfaces.