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1.
The release of tumor necrosis factor-alpha (TNF-) from cultured bovine alveolar macrophages (BAM) was evaluated following stimulation of BAM with bovine herpesvirus-1 (BHV-1), parainfluenza-3 (PI-3) virus, bovine respiratory syncytial virus (BRSV), Escherichia coli 0111:B4 endotoxin, Pasteurella haemolytica type 1 endotoxin, Pasteurella multocida endotoxin, and virus/endotoxin combinations. A cytotoxic assay system using Georgia bovine kidney cells as targets was used to measure TNF- activity. The cytotoxic activity was neutralized by an anti-human TNF- monoclonal antibody.

Stimulation of BAM with 1 median tissue culture infectious dose (TCID50) of live or ultraviolet (UV)-inactivated PI-3 virus/cell resulted in release of TNF- in significantly (P<0.05) higher amounts than sham-induced BAM. The quantities of TNF- released after live or UV-inactivated BHV-1 or BRSV induction were not significantly higher than sham-induced BAM. E. coli 0111:B4, P. haemolytica type 1 and P. multocida endotoxins stimulated TNF- release in a dose-dependent manner. Sequential exposure of BAM to 1 TCID50 per cell of either live BHV-1, PI-3 virus or BRSV and then 5 μg ml−1 of either E. coli 0111:B4, P. haemolytica type 1 or P. multocida endotoxin caused a significant (P<0.05) reduction in detectable TNF- in seven of nine virus/endotoxin combinations tested, when compared with 5 μg ml−1 of endotoxin alone. Parainfluenza-3 virus/endotoxin combinations stimulated higher TNF- release when compared with other virus/endotoxin combinations. Five out of six test animals had serum-neutralizing antibodies to PI-3 virus, one out of six had serum-neutralizing antibodies to BHV-1, and two out of six had serum-neutralizing antibodies to BRSV, suggesting a possible relationship between serum neutralizing antibodies and TNF- release from in vitro cultivated BAM.  相似文献   

2.
An old dog had an expansile lesion affecting the ulnar diaphysis. The lesion had clinical and radiographic features typical of a bone cyst; however, computed X-ray tomography indicated that the lesion had a tissue content incompatible with a true cyst. The histological diagnosis was osteosarcoma. This report emphasises the highly variable radiological appearance of canine osteosarcoma; biopsy is required to establish the diagnosis because the radiological signs may mimic a lesion of different aetiology.  相似文献   
3.
Totally 13575 ewes of two different breeds, Dala and Spel, were inseminated with semen, frozen in straws and thawed at 70°C for 8 sec. An insemination dose of 0.2 ml containing approx. 150 × 106 spermatozoa with at least 45 to 50% progressive motility was imerted 5 to 12 mm into the cervix. The insemination was performed once between 12 and 30 h after the onset of heat. The NR rate of the Dala ewes increased significantly during the season. The NR rate of the ewes inseminated before 15. November was 44.3%, from 15. to 20. November 52.2%. from 20. to 25. November 55.3% and from 25. November and later 61.4%. The corresponding values for the ewes of the Spel breed were 57.3, 58.7, 61.5 and 71.0% respectively, and only the difference between the two last values was statistically significant. The difference between the fertility of the two breeds was significant within each of the periods .  相似文献   
4.
In six experimental dogs, arthrographic quality and synovial inflammatory response with shoulder arthrography comparing meglumine-sodium diatrizoate (Urovison) and the monoacidic dimer, meglumine-sodium ioxaglate (Hexabrix) was evaluated. In our study initial films were of equally high diagnostic quality for both contrast media, but delayed films significantly favored ioxaglate for diagnostic quality. The rise in white blood cells in synovial fluid samples collected 24 hours after the arthrographic procedure was significantly lower after the use of ioxaglate. Histologic examination performed 14 days after the intra-articular injection revealed no drug related lesions.  相似文献   
5.
Adult populations ofMaladera matrida Argaman (Coleoptera: Scarabaeidae), a beetle highly injurious to agricultural crops, were studied in the coastal plain of Israel from 1985 to 1988. There were two generations annually. Adults emerged in March, April or May and disappeared in October or November. The beetles are on the wing, mate, and feed at twilight and in the dark. Feeding and mating behavior, sex ratio, and preferred food plants were studied.  相似文献   
6.
In this two year study we investigated the effect that the level of concentrate in feedlot diet had on the occurrence of health problems in bull calves belonging to two multibreed groups.

In each of the two years, the 168 day feedlot period was divided into two equal periods of 77 days with an intervening 14 day adjustment period. During the first period, the animals in half of the pens within each breed-group received a high concentrate (85% grain) diet (H) while the rest of the pens received a diet (L) of hay ad libitum and half as much concentrate as the bulls on high concentrate. The L diet contained an average of 48% grain. In the second period, diets of bulls in half of the pens within each breed-group were switched from L to H and vice versa. During the feedlot period, the incidence of sickness among bulls was recorded. Disease incidence was higher in the second year compared to the first. In the second year, 49 out of 56 (87.5%) calves on the high concentrate diet required treatment for respiratory infections compared to only four (7.14%) in bulls on the low concentrate diet. The results suggest that a high concentrate diet for animals in feedlots may be more stressful to calves coming directly to the feedlot following weaning compared to a low concentrate diet, thereby acting as an additional predisposing factor to respiratory infections.

  相似文献   
7.
Amplified fragment length polymorphism (AFLP) analysis was used to study genetic variation among 76 isolates of Verticillium. A dendrogram based on the AFLP data revealed three main groups. One group consisted of 35 European isolates derived from Brassica napus together with five Californian isolates taken from B. oleracea. This group displayed a high degree of genetic similarity and included three isolates earlier classified as Verticillium longisporum, indicating that all isolates in this group probably should be regarded as members of V. longisporum. V. dahliae isolates constituted the second group while the third group contained four V. albo-atrum isolates. In addition to these three groups, a cluster of six V. nigrescens isolates was observed. However, the genetic distances between the isolates of V. nigrescens were much higher than those between members in the other groups and the bootstrap value for the V. nigrescens cluster was subsequently low. Four isolates classified as V. tricorpus were highly diverse and did not cluster together. Analysis of molecular variance revealed that the isolates of V. longisporum were separated into four subgroups, based on geographic origin. The study furthermore shows that AFLP is a suitable method for studying population structure in Verticillium.  相似文献   
8.
微管、微丝特异性抑制剂处理对水稻抗病性的影响   总被引:3,自引:0,他引:3  
 微管特异性抑制剂oryzalin、微丝特异性抑制剂细胞松弛素A (cytochalasin A,CA)和细胞松弛素D (cytochalasin D,CD)的试验表明:oryzalin在5~50μmol/L、CA在0.5~1.0μg/mL、CD在1~20μg/mL的浓度范围内,对稻瘟病菌孢子的萌发和附着胞的形成基本上没有影响。采用以上几种细胞骨架特异性抑制剂处理水稻叶鞘都可以不同程度地抑制寄主细胞抗病菌扩展的能力。在抑制剂处理的水稻叶鞘细胞中,病菌扩展的速度加快。进一步的观察发现,抑制剂处理抑制水稻细胞抗病菌的扩展能力与水稻的抗病防卫反应如原生质颗粒化、多酚类物质的积累和HR发生的延迟是相关的。  相似文献   
9.
To improve genetic gain of breeding programs for village poultry production, breeding schemes with observations obtained in village production systems using individual (VIO) and group recording (VGO) were examined under different levels of genotype-by-environment-interactions (GxE). GxE was modeled by varying the correlation between traits measured in the breeding station and village environments for bodyweight (rg_BW) and egg production (rg_EP). Relative and absolute genetic gains obtained from VIO and VGO were used for comparison between the schemes. Results showed that village observations significantly improved genetic gains compared to the scheme without birds tested in the village. The improvement was only slightly larger with individual observations than with group observations. Higher rg_BW and rg_EP led to lower relative genetic gain, but a higher absolute gain of VIO and VGO. It is recommended to apply a breeding scheme using group recording of village performance when strong GxE in breeding for village poultry is expected.  相似文献   
10.
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