Intradural vasculitis and hemorrhage in full sibling Welsh springer spaniels

Two, full sibling, Welsh springer spaniel presented at 8 and 18 mo of age with rapidly progressive ataxia, recumbency, and pyrexia. The spinal cord contained extensive subdural hemorrhage and, in 1 dog, suppurative and necrotizing arteritis in the dura. The findings suggest a familial form of canine juvenile polyarteritis syndrome.     

Evaluation of various compounds to inhibit activity of matrix metalloproteinases in the tear film of horses with ulcerative keratitis

OBJECTIVE: To examine in vitro effects of various antiproteolytic compounds on activity of matrix metalloproteinase (MMP)-2 and -9 in the tear film of horses with active corneal ulcers. SAMPLE POPULATION: Samples of tear film obtained from the eyes of 34 horses with active ulcerative keratitis. PROCEDURE: Horses were sedated, and tear samples were collected from the lower fornix of 34 ulcerated eyes by use of capillary tubes. The protease inhibitors 0.2% EDTA, 0.1% doxycycline, 10% N-acetylcysteine (NAC), 0.1% solution of a modified dipeptide that contains hydroxamic acid (ie, ilomostat), 0.1% alpha1-proteinase inhibitor (PI), 0.5% alpha1-PI, and 100% fresh equine serum (ES) were used to treat pooled samples. Amount of latent and active MMP-2 and -9 was measured by optical density scanning of gelatin zymograms of treated and untreated tear samples. RESULTS: Pooled tear samples obtained from ulcerated eyes contained the latent and active forms of MMP-2 and -9. Compared with MMP activity in untreated samples, total MMP activity (sum of all bands detected) observed on the gelatin zymogram gels was reduced by 99.4% by EDTA, 96.3% by doxycycline, 98.8% by NAC, 98.9% by ilomostat, 52.4% by 0.1% alpha1-PI, 93.6% by 0.5% alpha1-PI, and 90.0% by ES. CONCLUSIONS AND CLINICAL RELEVANCE: We documented that EDTA, doxycycline, NAC, ilomostat, alpha1PI, and ES inhibited MMP activity in vitro. Because these compounds use different mechanisms to inhibit various families of proteases in the tear film of horses, a combination of these protease inhibitors may be beneficial for treatment of corneal ulcers in horses.     

Evaluation of iohexol clearance used to estimate glomerular filtration rate in clinically normal foals

OBJECTIVE: To determine whether pharmacokinetic analysis of data derived from a single i.v. dose of iohexol could be used to predict creatinine clearance and evaluate simplified methods for predicting serum clearance of iohexol with data derived from 2 or 3 blood samples in clinically normal foals. ANIMALS: 10 healthy foals. PROCEDURE: Serum disposition of iohexol and exogenous creatinine clearance was determined simultaneously in each foal (5 males and 5 females). A 3-compartment model of iohexol serum disposition was selected via standard methods. Iohexol clearance calculated from the model was compared with creatinine clearance. Separate limited-sample models were created with various combinations of sample times from the terminal slope of the plasma versus time profile for iohexol. Correction factors were determined for the limited-sample models, and iohexol clearance calculated via each method was compared with exogenous creatinine clearance by use of method comparison techniques. RESULTS: Mean exogenous creatinine clearance was 2.17 mL/min/kg. The disposition of iohexol was best described by a 3-compartment open model. Mean clearance value for iohexol was 2.15 mL/min/kg and was not significantly different from mean creatinine clearance. A method for predicting serum iohexol clearance based on a 2-sample protocol (3- and 4-hour samples) was developed. CONCLUSIONS AND CLINICAL RELEVANCE: Iohexol clearance can be used to predict exogenous creatinine clearance and can be determined from 2 blood samples taken after i.v. injection of iohexol. Appropriate correction factors for adult horses and horses with abnormal glomerular filtration rate need to be determined.     

Effect of fenoldopam on renal function after nephrotomy in normal dogs

OBJECTIVE: To evaluate effects of fenoldopam on renal function in normal dogs subjected to bisection nephrotomy. In addition, effects of bisection nephrotomy on renal function in normal dogs were evaluated. STUDY DESIGN: Controlled, randomized, blinded experiment. SAMPLE POPULATION: Sixteen mixed-breed adult dogs. METHODS: Dogs were paired for sex, body weight, and approximate age and assigned to 1 of 2 groups: fenoldopam (F) or placebo (P). Baseline glomerular filtration rate (GFR) based on quantitative renal scintigraphy using (99m)Tc-DTPA, blood urea nitrogen (BUN), serum creatinine (SCr), urinalysis, and urine culture were performed before surgery. Left nephrotomy was performed via median celiotomy. Group F dogs were administered intravenous (IV) fenoldopam (0.1 microg/kg/min) for 90 minutes, whereas group P dogs were administered an equivalent volume of saline (0.9 % NaCl) solution for 90 minutes. Temperature, heart rate, respiration, direct arterial blood pressure, and urine volume were recorded during anesthesia. Renal function was assessed by measuring SCr, BUN, and GFR at 1, 21, and 42 days after surgery. RESULTS: There was no significant difference between groups in measured physiologic variables. No significant difference in GFR, BUN, or SCr between groups or between operated or control kidneys was detected. CONCLUSIONS: Bisection nephrotomy in normal dogs with renal arterial occlusion of 15 minutes and using a simple continuous capsular closure does not adversely affect renal function. CLINICAL RELEVANCE: Bisection nephrotomy, as described in this study, does not decrease renal function; perioperative administration of renoprotective agents is not necessary in normal dogs.     

Effect of anticonvulsant dosages of potassium bromide on thyroid function and morphology in dogs

A placebo-controlled experiment was performed to evaluate the effect of potassium bromide on the canine thyroid gland. Basal total thyroxine, free thyroxine, and basal thyrotropin serum concentrations were evaluated over a 6-month period in potassium bromide-treated and control dogs. A thyrotropin-releasing hormone stimulation test was also performed in all dogs at the beginning and conclusion of the study. Thyroid histopathology was compared between treated and control dogs at the end of the study. No difference was detected in any parameter between the two groups at the end of the study. A decline in thyroid hormone concentrations over the course of the study did occur in both groups of dogs. Potassium bromide does not appear to have a significant effect on canine thyroid function or morphology.     

The accessory lung lobe in thoracic disease: a case series and anatomical review

Diseases of the accessory lung lobe (AccLL) are often overlooked in dogs and cats, perhaps because of its recessed location. Diseases of this lobe also can mimic diseases of the diaphragm or structures comprising the caudal mediastinum. Normal anatomy of the AccLL and the diagnostic tools used today will be reviewed to help differentiate disease of adjacent organs. Four cases will also be described to illustrate disease presentation and radiographic findings affecting this lobe.     

Cloning and sequence analysis of the complementary DNA for feline preproparathyroid hormone

OBJECTIVES: To clone and sequence the cDNA for feline preproparathyroid hormone (preproPTH) and to compare that sequence with other known parathyroid hormone (PTH) sequences. SAMPLE POPULATION: Parathyroid glands from 1 healthy cat. PROCEDURES: A cDNA library was constructed in lambda phage from feline parathyroid gland mRNA and screened with a radiolabeled canine PTH probe. Positive clones were sequenced, and nucleic acid and deduced amino acid sequences were analyzed and compared with known preproPTH and PTH sequences. RESULTS: Screening of approximately 2 X 10(5) recombinant plaques revealed 3 that hybridized with the canine PTH probe; 2 clones comprised the complete sequence for feline preproPTH. Feline preproPTH cDNA consisted of a 63-base pair (bp) 5'-untranslated region (UTR), a 348-bp coding region, and a 326-bp 3'-UTR. The coding region encoded a 115-amino acid peptide. Mature feline PTH consisted of 84 amino acids. Amino acid sequence analysis revealed that feline PTH was > 83% identical to canine, bovine, swine, equine, human, and macaque PTH and 69, 71, and 44% identical to mouse, rat, and chicken PTH, respectively. Within the region responsible for hormonal activity (amino acids 1 to 34), feline PTH was > 79% identical to other mammalian PTH sequences and 64% identical to the chicken sequence. CONCLUSIONS AND CLINICAL RELEVANCE: The amino acid sequence of PTH is conserved among mammalian species. Knowledge of the cDNA sequence for feline PTH may be useful to investigate disturbances of calcium metabolism and alterations in PTH expression in cats.     

Effects of diet restriction on life span and age-related changes in dogs

OBJECTIVE: To evaluate the effects of 25% diet restriction on life span of dogs and on markers of aging. DESIGN: Paired feeding study. ANIMALS: 48 Labrador Retrievers. PROCEDURES: Dogs were paired, and 1 dog in each pair was fed 25% less food than its pair-mate from 8 weeks of age until death. Serum biochemical analyses were performed, body condition was scored, and body composition was measured annually until 12 years of age. Age at onset of chronic disease and median (age when 50% of the dogs were deceased) and maximum (age when 90% of the dogs were deceased) life spans were evaluated. RESULTS: Compared with control dogs, food-restricted dogs weighed less and had lower body fat content and lower serum triglycerides, triiodothyronine, insulin, and glucose concentrations. Median life span was significantly longer for dogs in which food was restricted. The onset of clinical signs of chronic disease generally was delayed for food-restricted dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 25% restriction in food intake increased median life span and delayed the onset of signs of chronic disease in these dogs.     

Evaluation of a commercially available immunoassay for assessing adequacy of passive transfer in calves

OBJECTIVE: To evaluate diagnostic utility of a commercially available immunoassay for assessing adequacy of passive transfer of immunity in neonatal calves. DESIGN: Prospective study. ANIMALS: 123 calves. PROCEDURE: Blood and serum samples were obtained from the calves prior to 2 weeks of age. The immunoassay was performed, along with refractometry and an 18% sodium sulfite turbidity test. Serum IgG concentration was determined with a radial immunodiffusion assay. Sensitivity and specificity of the immunoassay, refractometry, and the sodium sulfite test were calculated by comparing results with results of the radial immunodiffusion assay. RESULTS: Sensitivity and specificity of the blood IgG immunoassay were 0.93 and 0.88, respectively, compared with 1.00 and 0.53 for the sodium sulfite test. For refractometry, sensitivity and specificity were 0.71 and 0.83, respectively, when a serum total solids concentration of 5.2 g/dl was used as the cutoff between positive and negative test results. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the immunoassay performs well in detecting calves with inadequate passive transfer of immunity.