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1.
Feather abnormalities and skin lesions caused by a papovavirus infection in budgerigars are described. Diseased one to 15 day old birds displayed a lack of nestling down feathers and filoplumes on the head and neck. Survivors older than 15 days exhibited retarded growth and temporary absence of feathers variable from bird to bird. Several birds between 15 and 25 days of age had flight feathers with total absence or marked sparseness of the vanes. After 25 days, feathers began to grow, although the tail and/or some flight feathers of some of the birds remained underdeveloped or absent for several weeks. Several of these affected birds were unable to fly and are called “runners”

Microscopic lesions in the feather follicles of the affected birds less than 15 days of age, were characterized by focal, multifocal or diffuse ballooning degeneration in the lateral and axial plate cells of the barb ridges with the presence of large basophilic or amphophilic intranuclear inclusions in the same cells. Focal areas of ballooning degeneration with intranuclear inclusions were also found in the epidermis. Clinical observations made on these birds are compared with those reported in the literature for French molt.

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2.
Common root rot (Aphanomyces euteiches Drechs.) has become a very destructive disease in the French pea crops since 1993. For an accurate investigation of the virulence variability among French A. euteiches populations and between French and foreign populations, a new set of differential pea genotypes was developed. Thirty-three American and European pea lines, displaying different levels of resistance, were screened in a growth chamber against two French isolates. Symptoms (disease severity from 0 to 5, evaluating symptom surface on roots and epicotyl) and percentage of top fresh weight (inoculated/uninoculated top fresh weight ratio) were measured. From this screening 12 relatively resistant lines, from various genetic backgrounds, were identified along with a highly susceptible control. This set of 13 genotypes was inoculated under controlled conditions with 14 isolates from France, Sweden, USA, Canada and New Zealand, to investigate genotype–isolate interactions. Root symptoms were rated (disease severity), and a susceptibility/resistance threshold was established at disease severity = 1. Significant quantitative interactions were observed, and five 'resistance patterns' were identified, leading to a set of six pea genotypes: Baccara (susceptible), Capella, MN313, 902131, 552 and PI180693. Fields trials of this set in 1999 and 2000 gave the same resistance rankings than in growth chamber conditions. This set will allow more accurate assessments of the variability in virulence/aggressiveness of A. euteiches isolates from France and foreign countries, and further investigations of the epidemiological and genetic basis of pea–A. euteiches interactions.  相似文献   
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This study represents an analysis of the principal clinical factors and pathological lesions of 150 cases of necrotic enteritis encountered during 1968 and 1969 in Quebec. Following multiple investigations no common factor was observed which might have explained the pathogenesis of the condition which was observed during every month of the year, especially from May to November. Birds two to four weeks of age were the most susceptible. The main lesion was a fibrino-necrotic enteritis always localized in the small intestine, either in its entire length or just a segment and characterized by the disappearance of the surface epithelium and necrosis of the villi. The lumen was filled with desquamated epithelial cells and bacteria. Foci of coagulation necrosis were observed in the liver and foci of nephrosis in the kidneys. A Gram+ bacillus, strictly anaerobic, was always isolated from the viscera.  相似文献   
7.
Malignant lymphoma is a common malignancy in birds. Paraneoplastic syndromes, which are commonly observed in domestic animals, have not been reported in association with lymphoma in birds. Hypercalcemia and hyperglobulinemia were found on plasma chemistry in two Amazon parrots, which were presented with aspecific symptoms. In both cases radiography and ultrasound demonstrated signs of hepatomegaly, which proved to be due to malignant lymphoma on postmortem examination. The hypercalcemia was found to be most consistent with a paraneoplastic effect of the malignant lymphoma in these birds. The exact origin of the hyperglobulinemia remains unclear.  相似文献   
8.
It has been shown that Escherichia coli isolates from lesions of cellulitis belong to a limited number of clonal groups distinct from those of isolates found in the environment of these birds. In this study, different in vitro methods were used to evaluate adherence properties of E. coli isolates from cellulitis lesions and environments of high- and low-cellulitis prevalence broiler flocks. One hundred isolates were tested by hemagglutination. Adherence to frozen sections of chicken skin and binding to soluble fibronectin were examined for 40 of these 100 isolates by immunofluorescence and by immunocytofluorometry, respectively. Localization of bacterial adherence to skin tissues was confirmed by immunohistochemistry. It was demonstrated that O78:K80 isolates from cellulitis lesions adhered to skin sections to a much greater extent in deeper than in superficial tissue layers. A greater bacterial adherence following growth in TSB at 37 C was demonstrated for isolates from flocks with high prevalence of cellulitis than for isolates from flocks with low prevalence of cellulitis. MANOVA analysis results showed a significant difference between superficial and deep tissue layers only for one set of isolates from flocks with high prevalence of cellulitis. Hemagglutinating activity was variable among the O78:K80 isolates obtained from flocks with high prevalence of cellulitis. The results obtained for some O78:K80 isolates following growth in TSB suggest a role for type 1 fimbriae or F1 in adherence to skin sections. This was reinforced by the finding that adherence was inhibited by D-mannose. Poultry E. coli isolates that express F1 had no affinity for soluble fibronectin, although localization of the adherence in skin sections suggested a role for extracellular matrix components such as collagen and insoluble fibronectin.  相似文献   
9.
OBJECTIVE: To determine whether hematologic and serum biochemical values for blood samples obtained from cats via vascular access ports (VAP) are comparable to those for samples obtained by direct venipuncture. DESIGN: Prospective study. ANIMALS: 14 healthy cats. PROCEDURE: A VAP was surgically implanted in a jugular vein in each cat. Blood samples were obtained from the VAP and by direct venipuncture of the contralateral jugular vein 10 weeks after VAP placement. Results of hematologic and serum biochemical analyses were compared by use of a paired t-test. The Pvalue to reject the null hypothesis was adjusted to account for multiple comparisons by using the Bonferroni procedure in which the nominal P-to-reject value is divided by the number of comparisons (0.05/24 = 0.002). RESULTS: Paired samples (VAP and venipuncture) obtained 10 weeks after VAP placement were evaluated for each cat. Of the 24 measured analytes, only potassium, total protein, and albumin concentrations differed significantly (P< 0.001 for all 3) between VAP and venipuncture samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that samples obtained from VAP are suitable for routine hematologic monitoring of feline cancer patients. Sample hemolysis may account for a slight increase in potassium, total protein, and albumin concentrations obtained from VAP samples. However, the values of variables most critical for monitoring of patients receiving chemotherapy (ie, mature neutrophil and platelet counts) are comparable. If proper techniques are used, VAP may be used for administration of chemotherapy as well as for blood collection in cats undergoing cancer treatment.  相似文献   
10.
ABSTRACT Spatial and temporal distribution of Maize streak virus (MSV, family Geminiviridae, genus Mastrevirus) was monitored in the vector species Cicadulina mbila and the nonvector species C. china? using conventional and real-time quantitative polymerase chain reaction. Sustained feeding on MSV-infected plants showed that virus accumulation reaches a maximum in C. china?, but not in C. mbila. After a 3-day acquisition access feeding period (AAP), MSV was detected in the gut, the hemolymph, and the head of C. mbila, but only in the gut of C. china?. Similarly, Digitaria streak virus (genus Mastrevirus), which is not transmitted by either of the two species, was only detected in the gut. MSV was detected in the hemolymph of C. mbila 3 h after the beginning of the AAP. Although viral DNA progressively decreases in the vector and nonvector species after a 3-day AAP, MSV DNA remained stable in the salivary glands of C. mbila.  相似文献   
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