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Ultrasonography of the urinary tract of female sheep
1992
Braun, U. | Schefer, U. | Gerber, D.
We determined the position, dimensions, and structure of the kidneys, ureters, bladder, and urethra of 62 female sheep by use of ultrasonography. A 5.0-MHz convex transducer was placed over the right flank to examine the kidneys, and a 5.0 MHz-linear transducer was used to examine the bladder and urethra transrectally. All examinations were performed on sheep in standing position. The left kidney was 7.1 to 8.9 cm long, 3.4 to 5.5 cm wide, and 3.3 to 4.7 cm deep. Diameter of the parenchyma and renal sinus of the left kidney ranged between 1.1 and 1.9 cm and 1.1 and 2.0 cm, respectively. Circumference of the medullary pyramids varied between 2.1 and 3.3 cm. Similar ultrasonographic measurements were obtained for the right kidney. The diameter of the bladder varied between 0.3 and 6.9 cm in 96.8% of the sheep. The diameter of the bladder could not be determined in 32% of the sheep because it was > 10 cm, and, therefore, was beyond the penetration depth of the scanner. The only part of the urethra that could be ultrasonographically visualized was the internal urethral orifice. It had diameter between 0.1 and 0.2 cm. The ureters could not be ultrasonographically visualized in any of the sheep examined. The urinary tract of 8 sheep was examined 10 times within 2 weeks to examine whether measurements were reproducible. The interassay variation coefficient determined ranged from 3.1 to 31.8%, although for most variables, it ranged between 5 and 11%. Measurements for the length and width of the kidneys had the smallest interassay variation coefficient, whereas values obtained for diameter of the bladder and urethra, as well as thickness of the bladder, had the largest. It was concluded that the ultrasonographic findings described in this study can be used as references for diagnosis of morphologic changes in the kidneys, bladder, and urethra of sheep.
Mostrar más [+] Menos [-]Acute effects of a gamma-glutamylated derivate of S-(1,2-dichlorovinyl)-L-cysteine on renal function and ultrasturcture in pentobarbital-anesthetized dogs: site-specific toxicity involving S1 and S2 cells of the proximal tubule
1992
Ridgewell, R.E. | Krejci, M.E. | Koechel, D.A.
It has been established that L-gamma-glutamylated derivatives of alpha-amino acids are delivered more efficiently to the kidneys than are the parent alpha-amino acids. Therefore, we synthesized L-gamma-glutamyl-S-(1,2-dichlorovinyl)-L-cysteine (L-gamma-glutamyl-L-DCVC), the simplest L-gamma-glutamylated derivative of the nephrotoxic alpha-amino acid S-(1,2-dichlorovinyl)-L-cysteine (L-DCVC), and investigated its effects on renal function and ultrastructure in pentobarbital-anesthetized dogs. Intravenous doses of 23.15 and 92.60 micromoles of L-gamma-glutamyl-L-DCVC/kg of body weight induced significant increases in urinary protein output and significant decreases in the clearance of inulin during the 6-hour post-injection period. Changes were not observed in any of the other 13 renal function variables or in the 11 plasma and blood variables that were monitored throughout the same period. Both doses of L-gamma-glutamyl-L-DCVC induced renal ultrastructural lesions in the S1 and S2 cells of the canine proximal tubule; the remaining 8 cell types downstream and the glomeruli were not damaged. The onset and magnitude of renal function changes and the cell types affected by L-gamma-glutamyl-L-DCVC were virtually identical to those observed previously following IV administration of equivalent doses of L-DCVC to pentobarbital-anesthetized dogs. Rapid removal of the L-gamma-glutamyl group from L-gamma-glutamyl-L-DCVC (ie, deglutamylation) resulting in formation of the parent alpha-amino acid, L-DCVC, can best explain the extreme similarity in the nephrotoxic profiles of these 2 toxicants.
Mostrar más [+] Menos [-]Changes in erythrocyte deformability in NaCl-induced right-sided cardiac failure in broiler chickens
1992
Mirsalimi, S.M. | O'Brien, P.J. | Julian, R.J.
In this study, we tested the hypothesis that erythrocyte deformability is decreased in the development of cardiac failure induced by NaCl toxicosis. Deformability of erythrocytes and routine hematologic and biochemical variables were measured in 6 of 50 chickens that were given 5 g of NaCl/L in their drinking water from day 7 to day 42, and were compared with values in 6 of 50 healthy chickens given free access to tap water. Deformability was assessed by passing a 10% suspension of erythrocytes through a polycarbonate membrane with 5 micromoles pores. Chickens were euthanatized and heart and body weights were determined. Treatment with NaCl induced right-sided cardiac failure up to day 28. The ratios of heart weight to body weight were greater, for right ventricle by 20 to 64% and for left ventricle by 15 to 27%, attributable to NaCl treatment. Deformability of erythrocytes of NaCl-treated chickens was markedly decreased, in association with increased erythrocyte size and plasma Na+ concentration. However, only part of the decreased deformability could be explained by swelling of erythrocytes. Decreased deformability could not be explained by increased cell viscosity because mean corpuscular hemoglobin concentration, the primary determinant of erythrocyte viscosity, was decreased. Because decreased deformability of erythrocytes has been demonstrated previously to be associated with increased vascular resistance, decreased deformability may have contributed to the development of right-sided cardiac failure in these chickens.
Mostrar más [+] Menos [-]Detection of Campylobacter upsaliensis in diarrheic dogs and cats, using a selective medium with cefoperazone
1992
Burnens, A.P. | Nicolet, J.
Using a newly formulated selective medium containing cefoperazone, we isolated 72 Campylobacter strains in fecal samples from 397 diarrheic dogs and cats. Of these, 39 were thermophilic catalase-negative Campylobacter species. We identified these Campylobacter strains by DNA:DNA hybridization, using digoxigenin-labeled total genomic DNA of 4 Campylobacter reference strains (C jejuni, C coli, C lari, and C upsaliensis) as a probe. The labeling was done with a commercially available kit. We could identify 66 of the 72 Campylobacter isolates to the species level with this method; identification with probes always agreed with conventional test results. Of the 66 identified strains, 33 were C upsaliensis and 33 were C jejuni. Six isolates could not be assigned to a known species with probes or conventional tests. On the basis of our findings, C upsaliensis is more resistant to cefoperazone than to cephalothin, thereby explaining the unexpected recovery of these campylobacters on cephalosporin-containing media.
Mostrar más [+] Menos [-]Evaluation of granulocytic ehrlichiosis in dogs of Missouri, including serologic status to Ehrlichia canis, Ehrlichia equi, and Borrelia burgdorferi
1992
Stockham, S.L. | Schmidt, D.A. | Curtis, K.S. | Schauf, B.G. | Tyler, J.W. | Simpson, S.T.
Canine granulocytic ehrlichiosis was diagnosed in 37 dogs by finding ehrlichial morulae in 0.1 to 26.2% of their blood neutrophils and eosinophils. All 37 dogs had clinical signs of arthritis or muscular stiffness. Titer to Ehrlichia canis was determined in sera from 31 of the 37 dogs; 25 dogs had titer ranging from 1:20 to 1:5,120. In the other 6 dogs, titer to E canis was < 1:10. The most common hematologic abnormality in these dogs, other than rickettsiemia, was thrombocytopenia. Granulocytes infected with ehrlichial organisms were not found in another 10 dogs that had clinical signs of arthritis or muscular stiffness. Of these 10 dogs, 3 had titer to E canis ranging from 1:40 to 1:320. Titer in the other 7 dogs was < 1:10. Ehrlichial morulae were not found in the granulocytes of 18 healthy dogs. Of these 18 dogs, 9 had titer to E canis ranging from 1:20 to 1:5,120. Titer in the other 9 dogs was < 1:10. Titer to Borrelia burgdorferi was determined in dogs with granulocytic ehrlichiosis, arthritic dogs without detected rickettsiemia, and in healthy dogs. Low titer determined by 2 laboratories was considered to be nonspecific reaction in all 3 groups of dogs and, thus, did not indicate that the arthritic disorders were attributable to canine borreliosis.
Mostrar más [+] Menos [-]Evaluation of total protein content in tears of dogs by polyacrylamide gel disk electrophoresis
1992
Barrera, R. | Jimenez, A. | Lopez, R. | Mane, M.C. | Rodriguez, J.F. | Molleda, J.M.
Concentration of total proteins was measured and sodium dodecyl sulfate-polyacrylamide gel disk electrophoresis was performed on tear and plasma samples obtained from 26 healthy dogs, and the results were compared. Mean +/- SEM concentration of total proteins in tears was 0.63 +/- 0.04 g/dl, and significant effects of age or gender were not found. The protein composition of tears in dogs was complex, and bands from light and heavy chains of immunoglobulins were identified by electrophoresis.
Mostrar más [+] Menos [-]Effect of initial restraint, weaning, and transport stress on baseline and ACTH-stimulated cortisol responses in beef calves of different genotypes
1992
Zavy, M.T. | Juniewicz, P.E. | Phillips, W.A. | VonTungeln, D.L.
The productivity and well-being of animals can be substantially affected by stress. This is particularly true in the case of beef calves that are subjected to a multitude of stressors over a short period during the first year of life. Perhaps the most often studied stress-responsive variable has been blood corticosteroid concentrations. Factors such as age, gender, genetics, and degree of prior experience, can influence how an animal perceives and responds to a given stressor. Few studies have tried to control these variables, and accordingly, many conflicting results have been published regarding the impact of various stressors on cortisol response. We measured baseline plasma cortisol concentration over a 44-day study in Bos indicus and Bos taurus calves. Plasma cortisol values in Bos indicus calves were higher (32.60 +/- 0.66 ng/ml) than values in calves of Bos taurus (25.81 +/- 0.76) breeding. A precipitous decrease in cortisol concentration was observed 7 days after transport stress in all calves. Baseline cortisol concentration did not provide any indication of the intensity of the various stressors. However, significant differences were readily observed after ACTH administration. On the basis of cortisol secretion, stresses of transport and weaning were similar and were the most stressful to calves, regardless of genotype.
Mostrar más [+] Menos [-]Effect of calf age and Salmonella bacterin type on ability to produce immunoglobulins directed against Salmonella whole cells or lipopolysaccharide
1992
Roden, L.D. | Smith, B.P. | Spier, S.J. | Dilling, G.W.
A commercially available Salmonella bacterin was administered to Holstein calves starting at 1 to 19 weeks of age. Serum samples were obtained before administering bacterin and at 2-week intervals thereafter. An ELISA with Salmonella dublin lipopolysaccharide (LPS) or S dublin whole cells as antigen, was used to measure specific IgG and IgM responses. Antibody responses to LPS were not detected from calves < 12 weeks old inoculated with killed bacterin. Immunoglobulin responses to whole-cell antigen were detected from all age groups of calves inoculated with the same killed Salmonella bacterin. Calves < 11 weeks old are able to produce immunoglobulins to some whole-cell antigens, but are unable to produce anti-LPS immunoglobulins when inoculated with killed Salmonella bacterin. This age-related response to killed Salmonella antigens may account, in part, for increased susceptibility to salmonellosis in calves < 12 weeks old. In comparison to the response for killed antigen, 8 calves given modified-live aromatic-dependent S dublin bacterin at 1 to 3 weeks of age had detectable anti-LPS immunoglobulin after immunization, although the response was not as rapid and was of a lesser magnitude than that of older calves given killed Salmonella bacterin.
Mostrar más [+] Menos [-]Keratin and associated proteins of the equine hoof wall
1992
Grosenbaugh, D.A. | Hood, D.M.
In this study, we described water-insoluble proteins extracted from the germinative regions (stratum internum and coronary band epithelium) and the cornified outer surface (stratum medium) of the equine hoof wall. Two major types of polypeptides were identified: the intermediate filaments (IF) and the IF-associated proteins. The IF, including keratins, composed a major portion of this fraction, had electrophoretic mobilities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the range of 40 to 80 kDa, and reacted with acidic or basic keratinspecific monoclonal antibodies. Differences in the composition of keratins between germinative layers and the stratum medium were seen. Another less well-characterized group of polypeptides associated with the IF also were extracted with the water-insoluble polypeptide fraction. These associated proteins had an apparent molecular weight between 10 and 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and contained a higher percentage of sulfur-containing amino acids than did the IF. Water-insoluble protein fractions compared favorably with those found in other less-specialized keratinizing tissue with respect to size, immunoreactivity with monoclonal antibody, and amino acid composition.
Mostrar más [+] Menos [-]Biomechanical comparison of three internal fixations for treatment of slipped capital femoral epiphysis in immature dogs
1992
Belkoff, S.M. | Millis, D.L. | Probst, C.W.
The biomechanical strength and stiffness of 3 fixation techniques used to repair acute slipped capital femoral epiphysis were evaluated in bone specimens from immature dogs. A servohydraulic testing machine was used to create slipped capital femoral epiphysis in 9 pairs of femurs by shearing the capital femoral epiphysis along the physis in a craniocaudal direction. The slip was reduced and repaired with 1, 2, or 3 double-pointed, 1.6-mm (0.062-inch) smooth pin(s) and retested. The strength and stiffness of each intact femur (which served as the control) and repaired femur were compared. Results of the study indicated that differences among the failure strengths of 1- and 2-pin fixations and their respective controls were not significant; however, the 3-pin fixation was 29% stronger than its control and was 60 and 45% stronger than the 1- and 2-pin fixations, respectively. One- and 2-pin fixations were 34 and 24% less stiff than their respective controls, whereas the stiffness of the 3-pin fixation was similar to its control. The 2- and 3-pin fixations were 48 and 76% stiffer, respectfully, than the 1-pin fixation, but were not significantly different, compared with each other.
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