Liver glutathione concentrations in dogs and cats with naturally occurring liver disease

OBJECTIVE: To determine total glutathione (GSH) and glutathione disulfide (GSSG) concentrations in liver tissues from dogs and cats with spontaneous liver disease. SAMPLE POPULATION: Liver biopsy specimens from 63 dogs and 20 cats with liver disease and 12 healthy dogs and 15 healthy cats. PROCEDURE: GSH was measured by use of an enzymatic method; GSSG was measured after 2-vinylpyridine extraction of reduced GSH. Concentrations were expressed by use of wet liver weight and concentration of tissue protein and DNA. RESULTS: Disorders included necroinflammatory liver diseases (24 dogs, 10 cats), extrahepatic bile duct obstruction (8 dogs, 3 cats), vacuolar hepatopathy (16 dogs), hepatic lipidosis (4 cats), portosystemic vascular anomalies (15 dogs), and hepatic lymphosarcoma (3 cats). Significantly higher liver GSH and protein concentrations and a lower tissue DNA concentration and ratio of reduced GSH-to-GSSG were found in healthy cats, compared with healthy dogs. Of 63 dogs and 20 cats with liver disease, 22 and 14 had low liver concentrations of GSH (micromol) per gram of tissue; 10 and 10 had low liver concentrations of GSH (nmol) per milligram of tissue protein; and 26 and 18 had low liver concentrations of GSH (nmol) per microgram of tissue DNA, respectively. Low liver tissue concentrations of GSH were found in cats with necroinflammatory liver disease and hepatic lipidosis. Low liver concentrations of GSH per microgram of tissue DNA were found in dogs with necroinflammatory liver disease and cats with necroinflammatory liver disease, extrahepatic bile duct occlusion, and hepatic lipidosis. CONCLUSIONS AND CLINICAL RELEVANCE: Low GSH values are common in necroinflammatory liver disorders, extrahepatic bile duct occlusion, and feline hepatic lipidosis. Cats may have higher risk than dogs for low liver GSH concentrations.     

Outcome of ameroid constrictor occlusion of single congenital extrahepatic portosystemic shunts in cats: 12 cases (1993-2000)

OBJECTIVE: To determine postoperative (< or = 6 days), short-term (< or = 90 days), and long-term (> or = 6 months) outcomes of cats undergoing ameroid constrictor occlusion of single congenital extrahepatic portosystemic shunts (PSS) and identify factors associated with outcome. DESIGN: Retrospective study. ANIMALS: 12 cats. PROCEDURE: Cats with single congenital PSS that underwent surgical placement of ameroid constrictors were identified. Follow-up information was obtained through telephone interviews and facsimile correspondence with referring veterinarians and owners. Results-All cats survived the surgery and were discharged from the hospital. One cat had seizures during the postoperative period. Five cats were clinically normal during follow-up evaluations within 90 days after the surgery. Long-term follow-up information was available for 9 cats. Three were clinically normal, 4 had been euthanatized because of progressive neurologic disease, and 2 had neurologic abnormalities that could not be controlled with medication. Four of 7 cats with continued or recurrent neurologic abnormalities 1 or more months after surgery had normal scintigraphic or hepatic function test results 2 to 6 months after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the long-term outcome of ameroid constrictor occlusion of PSS in cats is poor. Owners of older cats and cats with preexisting neurologic signs should be made aware of the potential for a poor outcome when considering surgical correction of this disease.     

Clinical features and outcome in dogs and cats with obsessive-compulsive disorder: 126 cases (1989-2000)

OBJECTIVE: To determine clinical features and outcome in dogs and cats with obsessive-compulsive disorder (OCD). DESIGN: Retrospective study. ANIMALS: 103 dogs and 23 cats. PROCEDURES: Records of patients with OCD were analyzed for clinical features, medication used, extent of behavior modification, and outcome. RESULTS: Most dogs affected with OCD had been obtained from breeders. Male dogs significantly outnumbered females (2:1). Female cats outnumbered male cats by 2:1 in a small sample. Most affected dogs lived in households with 2 or more humans and other dogs or cats, and had some formal training. Client compliance with behavior modification was high. A combination of behavior modification and medication resulted in a large decrease in intensity and frequency of OCD in most animals. Clomipramine was significantly more efficacious for treatment in dogs than was amitriptyline. Only 1 dog and 1 cat were euthanatized because of OCD during the study. CONCLUSIONS AND CLINICAL RELEVANCE: OCD in dogs does not appear to be associated with lack of training, lack of household stimulation, or social confinement. In cats, OCD may be associated with environmental and social stress. Obsessive-compulsive disorder appears at the time of social maturity and may have sporadic and heritable forms. With appropriate treatment (consistent behavior modification and treatment with clomipramine), frequency and intensity of clinical signs in most dogs and cats may decrease by > 50%. Success appears to depend on client understanding and compliance and the reasonable expectation that OCD cannot be cured, but can be well controlled.     

Microsporidiosis in a Gouldian finch (Erythrura [Chloebia] gouldiae)

A 12-day-old nestling Gouldian finch (Erythrura [Chloebia] gouldiae) was presented for investigation of a mortality problem in nestling finches raised by Bengalese finch foster parents. On histological examination, large numbers of spores consistent with a microsporidian organism were present within the small intestinal mucosa. Electron microscopy and molecular studies (sequencing the 5' end of the ssu rRNA gene) further defined the organism as Encephalitozoon hellem. Sequence homology with other eukaryotes was determined using a BLASTN search from the NCBI GenBank database. The finch isolate sequences showed greater than 99% homology with those of previously reported human and avian isolates.     

Increased susceptibility of peripheral blood mononuclear cells to equine herpes virus type 1 infection upon mitogen stimulation: a role of the cell cycle and of cell-to-cell transmission of the virus

Equine herpesvirus-1 (EHV-1) is an important pathogen of horses, causing abortion and nervous system disorders, even in vaccinated animals. During the cell-associated viremia, EHV-1 is carried by peripheral blood mononuclear cells (PBMC), mainly lymphocytes. In vitro, monocytes are the most important fraction of PBMC in which EHV-1 replicates, however, mitogen stimulation prior to EHV-1 infection increases the percentage of infected lymphocytes. The role of the cell cycle in viral replication and the role of cluster formation in cell-to-cell transmission of the virus were examined in mitogen-stimulated PBMC. Involvement of the cell cycle was examined by stimulating PBMC with ionomycin/phorbol dibutyrate (IONO/PDB) during 0, 12, 24 and 36 h prior to inoculation. Cell cycle distribution at the moment of inoculation and the percentage of EHV-1 antigen-positive PBMC at 0, 12 and 24 hours post inoculation (hpi) were determined by flow cytometry and immunofluorescence microscopy, respectively. The role of clusters was examined by immunofluorescence staining within clusters of stimulated PBMC using antibodies against EHV-1. Significant correlations were found between the increase of cells in the S- or G2/M-phase after a certain time interval of prestimulation and the increase of EHV-1 antigen-positive cells. The percentage of clusters with adjacent infected cells significantly increased from 3.3% at 8 hpi to 23.7% at 24 hpi and the maximal number of adjacent infected cells increased from 2 to 7. Addition of anti-EHV-1 hyperimmune serum did not significantly alter these percentages. Mitogen stimulation favours EHV-1 infection in PBMC by: (i) initiating cell proliferation and (ii) inducing formation of clusters, thereby facilitating direct cell-associated transmission of virus.     

Cardiopulmonary effects of intrathoracic insufflation in dogs

This study was designed to quantify the effects of incremental positive insufflation of the intrathoracic space on cardiac output (CO), heart rate (HR), arterial pressure (AP), central venous pressure (CVP), and percent saturation of hemoglobin with oxygen (SPO2) in anesthetized dogs. Seven healthy, adult dogs from terminal teaching laboratories were maintained under anesthesia with isoflurane delivered with a mechanical ventilator. The experimental variables were recorded before introduction of an intrathoracic catheter, at intrathoracic pressures (IP) of 0 mm Hg, 3 mm Hg insufflation, and additional increments of 1 mm Hg insufflation thereafter until the SPO2 remained <85% despite increases in minute volume. Finally the variables were measured again at 0 mm Hg IP. The cardiac output and systolic and diastolic AP significantly (P < 0.05) decreased at 3 mm Hg IP. Significant decreases in SPO2 were seen at 10 mm Hg IP. Significant increase in CVP was noted at 6 mm Hg IP. Heart rate decreased significantly at 5 to 6 mm Hg IP but was not decreased above 6 mm Hg IP. Given the degree of CO decrease at low intrathoracic pressures, insufflation-aided thoracoscopy should be used with caution and at the lowest possible insufflation pressure. Standard anesthetic monitoring variables such as HR and AP measurements may not accurately reflect the animal's cardiovascular status.     

Cardiac troponin I in feline hypertrophic cardiomyopathy

Measurement of plasma cardiac troponin I concentration ([cTnI]) is a sensitive and specific means for detecting myocardial damage in many mammalian species. Studies have shown that [cTnI] increases rapidly after cardiomyocyte injury. The molecular structure of cTnl is highly conserved across species, and current assays developed for its detection in humans have been validated in many species. In this study, [cTnI] was quantified using a 2-site sandwich assay in plasma of healthy control cats (n = 33) and cats with moderate to severe hypertrophic cardiomyopathy (HCM) (n = 20). [cTnI] was significantly higher in cats with HCM (median, 0.66 ng/mL; range, 0.05-10.93 ng/mL) as compared with normal cats (median, <0.03 ng/mL; range, <0.03-0.16 ng/mL) (P < .0001). An increase in [cTnI] was also highly sensitive (sensitivity = 85%) and specific (specificity = 97%) for differentiating cats with moderate to severe HCM from normal cats. [cTnI] was weakly correlated with diastolic thickness of the left ventricular free wall (r2 = .354; P = .009) but not with the diastolic thickness of the interventricular septum (P = .8467) or the left atrium: aorta ratio (P = .0652). Furthermore, cats with congestive heart failure at the time of cTnI analysis had a significantly higher [cTnI] than did cats that had never had heart failure and those whose heart failure was controlled at the time of analysis (P = .0095 and P = .0201, respectively). These data indicate that cats with HCM have ongoing myocardial damage. Although the origin of this damage is unknown, it most likely explains the replacement fibrosis that is consistently identified in cats with moderate to severe HCM.     

Complementary and alternative medicine for neurologic disorders

The use of complementary and alternative veterinary medicine in treating neurologic disorders has increased in popularity in response to advances in human alternative and integrative therapies. Neurolocalization of lesions to the brain, spinal cord, and neuromuscular systems is discussed, as well as the diagnostics and therapeutics used to treat such disorders. Emphasis is placed on integrative and alternative treatments for such neurologic diseases as seizures, cerebrovascular accidents, canine cognitive disorder, meningitis, intervertebral disc disease, fibrocartilagenous embolism, degenerative myelopathy, and myopathies. Thorough physical and neurologic examinations, establishment of a correct diagnosis, and integrative therapeutics are aimed at improving the overall quality of life of the veterinary patient.     

Bone Strength and Acetylcholinesterase Inhibition as Endpoints in Chlorpyrifos Toxicity toFundulus heteroclitus

Brain acetylcholinesterase (AChE) inhibition was measured during 4-week and 4-day episodic exposures to chlorpyrifos. Organisms were exposed to a seawater (−) control, an acetone (+) control (0.1%), and 0.625, 1.25, 2.5, 5.0, and 10.0 μg of chlorpyrifos L⁻¹in each test. These episodic exposures significantly depressed AChE activity at 2.5, 5.0, and 10.0 μg L⁻¹(weekly test) and at 1.25, 2.5, 5.0, and 10.0 μg L⁻¹(daily test). Six-hour pulsed exposure to chlorpyrifos inhibited brain AChE activity at concentrations as low as 1. 25 μg L⁻¹. Stress at failure of caudal vertebrae following episodic exposure was also tested. Analysis of samples from daily 6-h treatments found no differences after 2 days; however, vertebrae were significantly weaker (than controls) after 4 days. Analysis of weekly 6-h exposures found weaker caudal vertebrae after 2 weeks but not after 4 weeks.     

Field trial to determine the impact of providing additional care to litters on weaning weight of pigs

The purpose of this field trial was to determine if maximal care of pigs from birth until 16 d of age would result in a significant alteration in the survivorship and growth performance of the pigs compared with control pigs born in the same time period. Sows were randomly assigned to treatment group prior to farrowing. Control pigs received the standard, commercial farm care. In maximal care litters, pigs were dried off at farrowing, given a rubber mat in the creep area, and given electrolytes, chilled pigs were warmed and given colostrum or glucose, surgical instruments used for processing were dipped into an antiseptic between pigs, the castration wounds were sprayed with iodine, and sows were fed 3 times rather than twice a day. Pigs that received the maximal care weighed 170 g (+/− 80 g) more at 16 d of age than standard care pigs. Factors that reduced weight at 16 d included having a low birth weight, nursing a gilt or a parity 5–6 sow, nursing in a large litter, being clinically ill or being lame after 3 d of age, being cross-fostered and nursing an ill sow. In general, maximal care did not reduce mortality. Providing maximal care did improve weaning weights and enabled small birth weight pigs to reach 3.7 kg at 16 d of age.