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951.
Cyathostomins are important equine gastrointestinal parasites. Mass emergence of mucosal stage larvae causes a potentially fatal colitis. Mucosal stages are undetectable non-invasively. An assay that would estimate mucosal larval stage infection would greatly assist in treatment, control and prognosis. Previously, we identified two putative diagnostic antigens (20 and 25 kDa) in somatic larval preparations. Here, we describe their purification and antigen-specific IgG(T) responses to them. Western blots confirmed the purity of the antigens and showed that epitopes in the 20 kDa complex were specific to larval cyathostomins. No cross-reactive antigens appeared to be present in Parascaris equorum or Strongyloides westeri species. Low levels of cross-reactivity were observed in Strongylus edentatus and Strongylus vulgaris species. Use of purified antigens greatly reduced background binding in equine sera. These results indicate that both antigen complexes may be of use in a diagnostic assay.  相似文献   
952.
Atriplex species are tolerant to salinity and water stress and thus they are suitable for restoration of many degraded ecosystems. In addition, many Atriplex species offer good value as forages. We compared growth and leaf chemistry of Atriplex canescens, a well-known halophyte, and A. acanthocarpa, a poorly-studied species, as affected by salinity in a greenhouse study. Seeds and soil were collected in northern Mexico, the native range of these species. Plants were grown in pots containing native soil and irrigated with NaCl solutions of 0, 50, and 100 mM. Shoot growth of A. canescens declined 37% as NaCl treatments increased from 0 to 100 mM while shoot growth of A acanthocarpa was not significantly affected by salinity. The high salt tolerance of A. acanthocarpa was linked to a high accumulation of leaf sodium (Na) (7- to 13-fold higher than A. canescens). A. acanthocarpa had also higher growth rate than A. canescenes, making the former species a good candidate for cultivation, especially under saline conditions. Tissue concentration of potassium (K) in both species was minimally affected by the salinity treatments. Leaf nitrogen (N) concentration increased as plants faced higher salinity treatments, especially in A. canescens. The high salt tolerance and higher Na accumulation of A. acanthocarpa make this species an attractive choice for reclamation of saline areas. We suggest A. acanthocarpa should be explored as viable forage for cultivation and for reclamation of degraded areas just as A. canescens has been throughout the world.  相似文献   
953.
This retrospective study summarises the case details, presenting signs, management and outcome in cases of temporohyoid osteoarthropathy (THO) and describes the findings of diagnostic imaging modalities. The condition appears to be relatively rare in Europe and the objective of this study is to make clinicians aware that THO can have a range of various neurological and clinical presentations. The records of 2 referral equine practices in England were reviewed and 7 horses with THO diagnosed on guttural pouch endoscopy indentified. The clinical and neurological signs, diagnostic procedures, treatment and outcomes were reviewed. Although small, this group is the largest case series of THO from Europe. One horse was a yearling, whereas THO is generally considered usually to affect middle aged and older horses. Computed tomography was used to confirm the diagnosis and demonstrated stylohyoid bone fractures in 2 cases while there was mild increased radionuclide uptake in one of 2 cases undergoing nuclear scintigraphy. Treatment is still controversial, although ceratohyoidectomy led to complete resolution of signs in 2 of 5 cases thus treated and improvement in the other 3. One horse with mild signs treated with antimicrobials and nonsteroidal anti‐inflammatory drugs made a full recovery while another, presented with head shaking and managed with a phased exercise programme, improved but did not resolve completely.  相似文献   
954.
1. Hatching time, hatchability of fertile eggs and embryo mortality in relation to (1) physical quality of fresh eggs and (2) embryonic development during storage and incubation periods were analysed after egg storage for 1, 5 or 10 d at 30°C in the meat-type lines of Japanese quail, HG and LG, divergently selected for high and low relative weight gain between 11 and 28 d of age, respectively, and constant body weight at 49 d of age.

2. In both lines, the increase of egg storage temperature from 12°C (standard level) to 30°C increased the egg weight loss during storage, shortened the incubation period and reduced the hatching success.

3. Similar to standard egg storage temperature, LG quail hatched earlier than HG quail after egg storage at 30°C and early and late mortality of both lines increased with a prolonged period of egg storage. In contrast to the standard egg storage conditions, no line differences in hatchability were observed.

4. The results did not identify a relationship between the decrease in hatchability or embryo viability and line differences in external egg parameters as well as any important role of undesirable changes induced by a high storage temperature on albumen viscosity.

5. The pattern of embryonic death, low developmental rate of embryos and a dichotomy between the development of the extra-embryonic vascular system and the embryo itself during egg storage at high temperature implied that an insufficient nutrient supply in consequence of developmental delay could represent a key factor in increasing early and late embryo mortality.  相似文献   

955.
This is the first report of detection of Candidatus Mycoplasma haemolamae in alpacas in England. The primary case occurred in a three year-old male alpaca in the south-east of England which presented with a history of progressive weight loss, lethargy, swelling of the scrotum and pale mucous membranes. Blood smear examination revealed a moderate, regenerative anaemia, with numerous small basophilic coccoid structures consistent with Candidatus M haemolamae. To confirm the presence of Candidatus M haemolamae, a portion of the 16S rDNA gene was amplified and analysed by denaturing gradient gel electrophoresis (DGGE). 16S rDNA gene sequencing showed a 99.8 per cent homology with Candidatus M haemolamae sequences deposited in GenBank. Subsequently, a cross-sectional study was carried out to investigate the presence of Candidatus M haemolamae infection in the alpaca herd from which the primary case was detected (n=131). Blood smear examinations and PCR with DGGE were used and compared with a species-specific PCR. The prevalence of infection when PCR positive results were combined was 29 per cent. A substantial agreement between the PCR/DGGE and the species-specific PCR was found (κ=0.86). A significant association was also found between age and infection (P=0.04) while no significant association was found with sex or origin.  相似文献   
956.
To investigate the hepatic metabolism of the new insecticide flupyrazofos [O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphorothioate], isolated rat liver was perfused with flupyrazofos under single-pass conditions. In outflow perfusate and bile, 1-phenyl-3-trifluoromethyl-5-hydroxyprazole (PTMHP), PTMHP-sulfate and PTMHP-glucuronide conjugates were identified as the metabolites of flupyrazofos. However, O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphate (flupyrazofos oxon) was not detected. A HPLC method with UV detection was used to investigate the hepatic disposition of flupyrazofos and its metabolite PTMHP. The concentrations of flupyrazofos, PTMHP and PTMHP conjugates in outflow perfusate reached steady-state levels within 20 min after commencing perfusion of 7.3 microM flupyrazofos. At steady state, the mean extraction ratio of flupyrazofos was 0.93 (+/- 0.01) and clearance was 26.1 (+/- 0.2) ml min-1 which nearly approached perfusate flow rate (28 ml min-1). PTMHP accounted for 55.7 (+/- 5.8)% of eliminated flupyrazofos and was recovered as unchanged PTMHP, PTMHP-sulfate and PTMHP-glucuronide in the bile as well as the outflow perfusate.  相似文献   
957.
An adult female neutered crossbred dog was referred in respiratory distress. Thoracic radiographs revealed tracheal narrowing with a soft tissue opacity dorsal to the trachea, near the thoracic inlet, and a patchy interstitial pulmonary infiltrate. The tracheal narrowing was thought to be due to a combination of intraluminal haemorrhage and mediastinal haemorrhage resulting from a coagulopathy caused by anticoagulant rodenticide intoxication. Treatment included supportive care and administration of vitamin K1, and the dog showed a complete resolution of the clinical signs.  相似文献   
958.
Dogs were examined ophthalmoscopically to determine the prevalence and type of ocular lesions associated with naturally acquired Rocky Mountain spotted fever (RMSF). In a consecutive series of 11 dogs with serologically confirmed RMSF, 9 had ocular involvement reflecting various degrees of vascular damage, including subconjunctival hemorrhage, hyphema, anterior uveitis, iris stromal hemorrhage, retinal petechiae, and focal areas of retinal edema and perivascular inflammatory cell infiltrate. The ophthalmic lesions generally were mild, and most resolved without complication after systemic administration of appropriate antibiotics. The high prevalence of ocular lesions in these dogs suggested that critical ophthalmologic evaluation is a useful diagnostic tool for the early detection and management of RMSF in dogs.  相似文献   
959.
Four experiments with 270, 44, 432 and 66800 Leghorn hens were carried out to investigate the influence of various Mn additions to diets differed in mineral or Ca contents on egg shell quality. The addition of 300 mg Mn/kg diet improved significantly egg shell breaking strength by 4 N over one year. The supply of 50-500 mg Mn/kg diet for 10-24 weeks of the second half of laying year did not influence the egg shell quality. Addition of mineral mixture or Ca grit to layer rations with adequate or higher Mn levels did not influence egg shell strength. High mineral content in a low manganese diet increased number of cracks by 3%. Strength, weight and ash content of tibia were significantly reduced by feeding a low mineral level. Addition of 50-150 mg Mn per kg low mineral diet normalized partially tibia stability in young hens. It was concluded that supplied dietary Manganese influences calcification positively only in young hens. High levels of Ca did not influence the effects of Mn. 50 mg Mn per kg layers mixture have been considered as an essential supply.  相似文献   
960.
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR.  相似文献   
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