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991.
Ollulanus tricuspus is a parasite of the stomach of domestic cats and other animals, with a worldwide distribution. It can sometimes cause severe gastritis. Fifty-five cat stomachs were examined for O.tricuspis using three techniques. O.tricuspis was found in seven stomachs (13%) from adult cats; the number of parasites recovered from individual cats ranged from 9 to 119 (mean 54). The prevalence was higher than that previously recorded in New Zealand. Repeated dilution and sedimentation of the stomach contents and mucosal washings was found to be the most reliable detection method, being positive in all of the detected infections. Pepsin/HCI digestion of the stomach mucosa detected only 71% and punch sampling of the mucosa only 29% of these infections. This contrasts with an overseas study indicating that, in heavily infected cats, these techniques are similar in sensitivity. No macroscopic lesions were seen in the stomachs of infected cats.  相似文献   
992.
Infection of commercially reared white leghorn and white rock hens with adenovirus 127 was associated with decreases in total egg production, external egg quality, egg weight (P less than 0.01), and eggshell thickness (P less than 0.01). The egg-production and egg-quality disturbances were transient, and production returned to normal approximately 4 weeks postinfection. Infection of white leghorns with a hemagglutinating adenovirus isolated from Missouri ducks did not adversely affect egg production, external egg quality, or eggshell thickness, but it was associated with decreased egg weight (P less than 0.01). Prior infection with the duck adenovirus prevented the adverse egg-production effects of adenovirus 127 infection. Mean hemagglutination-inhibition antibody titers of chickens infected with adenovirus 127 or with duck adenovirus ranged from 1:588 to 1:10809, and mean titers of uninfected chickens did not exceed 1:2.  相似文献   
993.
The morphological and biochemical consequences of transplanting affected bone marrow from donor BALB/c mice with a lysosomal storage disorder (BALB/c LSD) into normal recipient mice were studied. Bone marrow was removed from normal BALB/c and BALB/c LSD mice and transfused into normal BALB/c recipient mice four hours after the mice received 850 rads of irradiation. Tissues of the recipient mice were examined 240 days later. This study revealed that the defective cells that constituted the visceral lesions of BALB/c LSD could be transplanted to normal BALB/c mice by the use of bone marrow from affected BALB/c LSD homozygote; that the defective cells of BALB/c LSD proliferated and disseminated throughout the mononuclear phagocytic system of the recipient; that there were increases in cholesterol, sphingolipids, and cystine with decreases in sphingomyelinase and glucocerebrosidase activity in tissues of the recipients; and that the recipients survived substantially longer than BALB/c LSD homozygotes and their lifespan was compromised mainly by the secondary effects of irradiation. These lesions, although not as extensive as in homozygous BALB/c LSD, paralleled the lesions which develop in BALB/c LSD. Since the recipient mice were not compromised by the short life span (70 days) of the BALB/c LSD mice, they may be used to study the long-term chronic effects of these metabolic lesions.  相似文献   
994.
A malignant catarrhal fever-like syndrome in indonesian swamp buffalo was experimentally transmitted to one of 2 Bos indicus and 3 of 3 Bos javanicus cattle by intravenous inoculation of 250 ml of citrated, whole blood from affected buffaloes. The 4 cattle developed clinical signs of disease on average 32.5 days after receiving the inoculation of blood. The 4 cattle died after a variable period of illness. None of a further 3 B. javanicus cattle inoculated intravenously with a spleen homogenate prepared from another affected buffalo developed the disease. The experimental disease was clinically and pathologically similar to the natural disease in buffaloes although differences were noted. Attempts to adapt the agent to mice, guinea pigs and rabbits failed. A cytopathic agent (Japanese encephalitis virus) was isolated from the spleen of one buffalo with clinical signs but was not considered significant. Sixty-three B. indicus, 7 B. javanicus (and 6 of their crosses), 3 B. taurus and 4 Bubalus bubalis (Murrah buffalo) were kept in the same quarters where 50 of 177 swamp buffaloes died between September 1979 and May 1982. Four of the 7 B. javanicus cattle developed the clinical signs of disease and died. All the other cattle in contact remained healthy.  相似文献   
995.
Ultrastructural changes are reported in the kidney and liver of 20-day-old broiler chicks fed ochratoxin A (OA), incorporated in the diet at levels of 2 and 4 ppm. Changes in the kidney included the presence of abnormally shaped mitochondria in the proximal convoluted tubules. There was an increase in the size and number of mitochondrial dense granules and cytoplasmic peroxisomes. Intranuclear and cytoplasmic lipid droplets and electron dense round bodies in the dilated smooth endoplasmic reticulum were also noted. Regional thickening and degeneration of the glomerular basement membrane was observed in some cases. In the liver from OA fed birds there was an increased accumulation of cytoplasmic glycogen in the hepatocytes. Abnormal mitochondrial ring forms in the kidney and the accumulation of glycogen in the liver are considered to be of diagnostic significance in ochratoxicosis of young broiler chicks. The severity of the changes was found to be dose related. These results suggest that the mitochondria in the proximal convoluted tubules of kidney were most sensitive to OA toxicity.  相似文献   
996.
Trichostrongylid burdens in 1 to 2-year-old dairy heifers were estimated after they grazed with a dairy herd for up to 12 months. Ostertagia ostertagi, Trichostrongylus axei and Cooperia oncophora represented 79.5, 12.7 and 7.8% respectively of all trichostrongylids recovered. The largest burden was 97,000 trichostrongyles with less than 20,000 being the typical burden. Clinical disease was not observed. The strain of O. ostertagi present was capable of inhibition and was not necessarily controlled by anthelmintics. Availability of infective larvae increased with the onset of spring when "modified tracer" calves accumulated up to 30,000 trichostrongyles over intervals of one month. From July to September each year, up to 80% of the Ostertagia burden in these animals were inhibited larvae. Faecal strongyloid egg counts fell from less than an average of 60 eggs per gram to 10 eggs per gram when the heifers were one and 2 years old, respectively. Mature cows continually passed few eggs in their faeces.  相似文献   
997.
Survey of thyroglobulin autoantibodies in dogs   总被引:1,自引:0,他引:1  
An enzyme-linked immunosorbent assay was used to detect autoantibodies to thyroglobulin in dogs with and without clinical evidence of thyroid disease. Autoantibodies were found in 59% of 34 clinically hypothyroid dogs, 43% of 65 dogs with nonthyroidal endocrine diseases, 47% of 64 healthy dogs closely related to antibody-positive canine hospital patients, and 13% of 1,057 canine hospital patients without endocrine disorders. Dogs with bacterial skin disease and alopecia of unknown causes had an increased prevalence of autoantibodies compared with the prevalence of autoantibodies in healthy dogs and dogs with other diseases. Three breeds of dogs, Great Danes, Irish Setters, and Old English Sheepdogs, had an increased occurrence of autoantibodies compared with that in other breeds and dogs of mixed breeding. A familial tendency to thyroid autoimmunity was demonstrated in a group of Great Dane dogs. The occurrence of autoantibodies was not influenced by age or sex. Thyroid function, as assessed by total thyroxine estimation, was depressed in hospitalized dogs compared with the thyroid function in healthy dogs, irrespective of thyroglobulin-antibody status. Two of 11 autoantibody-positive dogs monitored for an 18-month period developed low thyroxine concentration and depressed thyroid responsiveness to exogeneous thyrotropin stimulation.  相似文献   
998.
Intra-articular tissue response to analytical grade metrizamide in dogs   总被引:1,自引:0,他引:1  
The effect of analytical grade metrizamide (AM) injected into the canine stifle, for purposes of arthrography, was studied in 12 adult dogs using saline solution as the control solution injected into the contralateral joints. The AM was used at a concentration of 280 mg of iodine/ml and was administered at the dose of 0.3 ml/cm thickness of the stifle joint. For each joint, arthrocentesis was done before and 7 days after injection of either the contrast medium or saline solution. Physical, biochemical, and cytologic examinations were done on the synovial fluid while the synovial membranes and femoral articular cartilages were sectioned, stained, and examined for histopathologic changes. At the 95% confidence level, significant differences in the total and differential mononuclear cell counts were not seen between the AM- and saline solution-injected joints. However, some subtle changes in the synovial membranes were observed. Intra-articular injection of AM or saline solution initiated a mild inflammatory response, the AM causing slightly more response than the saline solution.  相似文献   
999.
Effects of propranolol on thyroid function in the dog   总被引:1,自引:0,他引:1  
The effect of propranolol on thyroid function was evaluated in 6 mature euthyroid Beagles. Propranolol was administered orally in doses of 20 mg given 3 times daily for 2 weeks and then increased to 40 mg given 3 times daily for an additional 2 weeks. Six age- and sex-matched, euthyroid Beagles served as controls. Serum base-line concentrations of tetraiodothyronine (T4), triiodothyronine (T3), and reverse triiodothyronine (rT3) were measured before propranolol administration and at weekly intervals thereafter. Thyroid response to 5 IU of aqueous thyroid stimulating hormone administered IV was monitored before propranolol administration and at the 2- and 4-week treatment intervals. The T4, T3, and rT3 concentrations were measured by radioimmunoassay. There were no significant differences in base-line or postthyroid stimulating hormone serum concentrations of T4, T3, or rT3 in any individual or between the treatment or control groups at any treatment interval (P greater than 0.05). Seemingly, the therapeutic use of propranolol in euthyroid dogs should not alter thyroid hormone metabolism.  相似文献   
1000.
  1. An enzymatic ‘reaction rate’ micro-method for the rapid routine estimation of D-B-hydroxybutyrate (D-B-HOB) in ruminant plasma, using an I.L. Multistat III centrifugal analyzer, is described.
  2. Reaction conditions were optimized to give a linear response for plasma D-B-HOB concentrations between 100 and 2500 μmoles per litre, at 30°C and pH 9.0.
  3. For the standardized method the within-run and between-run coefficients of variation for deproteinised ovine plasma were consistently less than 3.5%.
  4. There was good agreement between plasma concentrations obtained by the present method and both original U.V. end-point technique (r=0.927b=0.950) and a colorimetric end-point procedure (r=0.937. b=0.879).
  5. Utreated ovine and bovine plasma consistently exhibited high ‘blank’ activity and this was directly correlated with plasma lactate dehydrogenase (LDH) activity in both species (r=0.971; p<0.001 and r=0.949; p<0.001 respectively). The distribution of LDH activity in man was similar to sheep but, contrastingly, non-specific interference was extremely low in human plasma and unrelated to LDH. Horse, chicken and rat had negligible ‘blank” activity and comparatively low LDH levels. In both cattle and sheep non-specific interference was abolished by perchloric acid precipitation. In the sheep subtraction of ‘blank’ activity gave D-H-HOB concentrations for untreated plasma comparable to those in deproteinised samples. However, in the bovine, D-B-HOB levels remained significantly (t=6.44; p<0.001) higher even after ‘blank’ correlation. In contrast to man and other non-ruminants, perchloric acid precipitation is essential in ruminants to avoid false overestimation of plasma D-B-HOB levels.
  6. Plasma with EDTA as anticoagulant and serum gave concentrations of D-B-HOB approximately 60% lower, than samples containing heparin or oxalate/fluoride. However, heparin was associated with much higher (up to 50%) non-specific NAD rduction than oxalate/fluoride.
  7. High levels of acetoacetate (400–1000 μmoles per litre) reduced the recovery of D-B-HOB from ovine plasma by less than 10%. This effect was negated by the inclusion of hydrazine hydrates in the reaction mixture. Perchlorate ion concentrations above 25 μmoles per litre per test dramatically inhibited the assay in ovine plasma, and therefore precipitation conditions must be carefully controlled.
  8. Plasma with oxalate/fluoride as anticoagulant showed the greatest stability in storage; 24 hours at room temperature, one week at +4°C and at least one month at ?20°C.
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