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991.
A microplate enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to avian leukosis virus (ALV) of subgroups A and B in infected chickens was developed with the use of Rous-associated virus (RAV)-1 (subgroup A) and RAV-2 (subgroup B) antigens purified by sucrose-gradient centrifugation. The antigen was used for ELISA after treatment with Triton X-100. In the ELISA, the subgroup viral antigen reacted strongly with homologous antiserum but also reacted with heterologous antiserum. Tests with serum absorbed with purified homologous and heterologous virus and tests for antigen-blocking by group-specific antibodies to ALV revealed that the reaction was caused mainly by subgroup-specific antibodies. The ELISA was 8 to 32 times more sensitive than the virus-neutralization (VN) test and detected antibodies to ALV earlier than the VN test in chickens infected experimentally with RAV-1 and RAV-2. In field application of the ELISA, 44.2% of 484 chicken sera were positive for RAV-1 and/or RAV-2 antigen, and 80.4% of flocks were positive. These findings indicate that ELISA is superior to the VN test in sensitivity, simplicity, rapidity, and applicability for large-scale field surveys for ALV infection. 相似文献
992.
An indirect hemagglutination (IHA) test using sonicated extract as the antigen was developed for the detection of antibodies to Clostridium chauvoei. This antigen can be adsorbed onto glutaraldehyde-fixed sheep red blood cells treated with tannic acid and can be destroyed by trypsin and heat treatment. It corresponded well with the flagella of the organism, when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the gel diffusion test. No serological cross-reactivity was found in the IHA test when the antigen was tested against 4 species of clostridial antibodies. Our results suggest that the IHA test mainly detects antibodies against the flagella of C. chauvoei. 相似文献
993.
Results of the effect of cocoa pod ash and KHCO3 on phosphatase activity of some cocoa soils of Ghana are reported. Phosphatase activity of control soils generally decreased with duration of incubation. Higher rates of the ash application, regardless of time, resulted in a lower phosphatase activity than the control. This inhibition, among other factors, may be due to the presence of high available P and certain cations such as Mn and Zn. The KHCO3 increased the activity of the phosphatase in all soils when compared with the control. 相似文献
994.
995.
996.
O bjective : To characterise lipid profile in dogs with tail chasing.
M ethods : Fifteen dogs with tail chasing were included in this study. A behavioural diagnosis was made for each dog on the basis of the dog's behavioural history, clinical signs and results of other medical assessments. None of the dogs had concurrent medical disease that would account for compulsive tail chasing. Blood samples were taken from each dog after a fasting period of 12 to 16 hours to measure total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and very low-density lipoprotein cholesterol levels. Fifteen control dogs were also enrolled on the basis of normal physical examination results, complete blood count and serum biochemistry profiles.
R esults : Dogs with tail chasing had significantly higher total cholesterol (P < 0·01), high-density lipoprotein cholesterol (P<0·05) and low-density lipoprotein cholesterol (P<0·001) compared with control dogs. Very low-density lipoprotein cholesterol and triglyceride levels did not differ significantly between the groups.
C linical S ignificance : Tail chasing may be associated with serum cholesterol elevations in dogs. High serum cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol levels may be used as biochemical parameters of compulsive tail chasing in clinical settings. 相似文献
M ethods : Fifteen dogs with tail chasing were included in this study. A behavioural diagnosis was made for each dog on the basis of the dog's behavioural history, clinical signs and results of other medical assessments. None of the dogs had concurrent medical disease that would account for compulsive tail chasing. Blood samples were taken from each dog after a fasting period of 12 to 16 hours to measure total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and very low-density lipoprotein cholesterol levels. Fifteen control dogs were also enrolled on the basis of normal physical examination results, complete blood count and serum biochemistry profiles.
R esults : Dogs with tail chasing had significantly higher total cholesterol (P < 0·01), high-density lipoprotein cholesterol (P<0·05) and low-density lipoprotein cholesterol (P<0·001) compared with control dogs. Very low-density lipoprotein cholesterol and triglyceride levels did not differ significantly between the groups.
C linical S ignificance : Tail chasing may be associated with serum cholesterol elevations in dogs. High serum cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol levels may be used as biochemical parameters of compulsive tail chasing in clinical settings. 相似文献
997.
Porcine group C rotavirus as a cause of neonatal diarrhea in a Quebec swine herd. 总被引:3,自引:0,他引:3 下载免费PDF全文
A porcine group C rotavirus was found to be the unique cause of a problem of enzootic neonatal diarrhea in a minimal disease herd composed of 190 sows on a continuous farrowing program. During the outbreaks of diarrhea, 10 to 80% of the litters were affected with a morbidity rate of 100% and case fatality rates of 5 to 10%. Clinical signs began 24 to 48 h after birth and were characterized by a profuse yellow diarrhea lasting a few days. Piglets from different outbreaks of diarrhea were necropsied. They had multifocal villous atrophy in the small intestine, especially in the ileum. Group C rotavirus was demonstrated by direct immunofluorescent staining of frozen intestinal sections and by polyacrylamide gel electrophoresis of viral RNA extracted from the intestinal contents of diarrheic piglets. The infection with clinical illness and lesions was reproduced experimentally in newborn piglets by oral inoculation of a suspension prepared from a pool of intestinal contents from diarrheic piglets. 相似文献
998.
Blood and tissue concentrations of ampicillin in chickens 总被引:1,自引:0,他引:1
M Atef A Y el-Gendi M G el-Sayed A M Amer 《DTW. Deutsche tier?rztliche Wochenschrift》1986,93(3):110-112
999.
Accurate assessment of genetic similarity is important for plant breeding, germplasm enhancement and conservation of plant
genetic resources. A comparative analysis of genome diversity among a group of six-rowed spring barley (Hordeum vulgare L.) cultivars was carried out using sequence-specific amplified polymorphism (S-SAP) and single nucleotide polymorphism (SNP),
with the results compared to the kinship coefficients derived from the pedigree data. Mean pair-wise GS values were estimated
to be 0.0957 ± 0.144 (Kinship), 0.491 ± 0.189 (SNPs), and 0.602 ± 0.098 (S-SAPs). S-SAP and SNP-based genetic similarity (GS)
values were normally distributed but kinship values had a non-normal and skewed distribution. Pair-wise correlation of GS
values were lowest for the S-SAP and the SNP matrices (r =; 0.040, p<0.230) and highest for the SNP and pedigree matrices (r =; 0.240, p < 0.001). Analysis of molecular variance (AMOVA) attributed about 90.4% of observed variation to the cultivars within each
of the malting and feed groups. Variance component between malting and feed groups was 6.6% for both SNP and S-SAP data suggesting
lack of a significant genetic differentiation along this agronomic division. The remaining 3% of variation was attributed
to genetic diversity within cultivars. Although both DNA-based marker systems were able to differentiate all barley cultivars,
significant difference were observed in the pattern of genetic relationships obtained by the two marker systems and the pedigree
data. 相似文献
1000.
Ohne Zusammenfassung 相似文献