犬细粒棘球绦虫粪抗原夹心ELISA检测方法的建立

为建立特异性和敏感性高的检验犬细粒棘球绦虫感染的方法。用细粒棘球绦虫(简称,Eg)成虫抗原分别免疫兔和绵羊,收集高免血清,纯化的高免抗体。依据抗体夹心ELISA工作原理,以兔抗体包被,检测感染Eg、不同犬带科绦虫的实验犬和空白犬粪样,绵羊抗体扑捉抗原,HRP标记兔抗绵羊IgG(1∶8 000)催化显色,用酶标仪测定OD 405nm吸光度,用以确定其特异性和敏感性。试验结果表明,敏感性为82.69%(43/52),特异性为85.88%(140/163);粪抗原在感染细粒棘球绦虫16d后可检出,最低抗原浓度为9.7ng/mL即犬感染5条成虫时可检测出阳性。该检测方法具有较好的特异性和灵敏性,为进一步研制检测细粒棘球绦虫虫体抗原ELISA检测试剂盒奠定了基础。     

Mastitis associated with ovine progressive pneumonia virus infection in sheep

Eighteen ewes were experimentally infected with ovine progressive pneumonia virus and their mammary glands were examined for lesions and virus at 2.5 to 10 years postinoculation. Lesions were seen in 14 of 18 sheep; virus was isolated from 4 of 8 sheep. Lesion consisted of an interstitial accumulation of lymphocytes with periductal lymphoid nodules, and epithelial vacuolation and necrosis at the site of the lymphoid nodules.     

Comparison of bronchoalveolar lavage fluid obtained from Mannheimia haemolytica-inoculated calves with and without prior treatment with the selectin inhibitor TBC1269

OBJECTIVES: To determine effects of selectin inhibitor TBC1269 on neutrophil infiltration, and neutrophil-associated injury during pneumonia induced by Mannheimia haemolytica and concentration of antimicrobial anionic peptide (AAP) in bronchoalveolar lavage fluid (BALF) as well as antimicrobial activity of BALF from healthy (control) neonatal calves, neonatal calves with M haemolytica-induced pneumonia, neonatal calves with prior treatment with TBC1269, and adult cattle. ANIMALS: Eighteen 1- to 3-day-old calves and 9 adult cattle. PROCEDURE: Calves were inoculated with M haemolytica or pyrogen-free saline (0.14M NaCl) solution into the right cranial lung lobe, and BALF was collected 2 or 6 hours after inoculation. Thirty minutes before and 2 hours after inoculation, 4 calves received TBC1269. The BALF collected from 9 adult cattle was used for comparison of BALF AAP concentration and antimicrobial activity. Protein concentration and neutrophil differential percentage and degeneration in BALF were determined. An ELISA and killing assay were used to determine BALF AAP concentration and antimicrobial activity, respectively. RESULTS: Total protein concentration was significantly decreased in BALF from calves receiving TBC1269. Similar concentrations of AAP were detected in BALF from all calves, which were 3-fold higher than those in BALF from adult cattle. However, BALF from neonates had little or no anti-M haemolytica activity. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that TBC1269 decreases pulmonary tissue injury in neonatal calves infected with M haemolytica. Although AAP is detectable in neonatal BALF at 3 times the concentration detected in adult BALF, neonatal BALF lacks antimicrobial activity for M haemolytica.     

A selectin inhibitor decreases neutrophil infiltration during acute Mannheimia haemolytica pneumonia

The degree to which the selectin inhibitor TBC1269 reduces neutrophil infiltration in specific microscopic locations of the lung during acute pneumonia of neonates was determined. Neonatal calves were inoculated intrabronchially with Mannheimia (Pasteurella) haemolytica or saline, and lung tissue was collected at 2 and 6 hours postinoculation (PI). One 6-hour group inoculated with M. haemolytica received TBC1269 intravenously before and after inoculation with M. haemolytica. Infiltrates of neutrophils were significantly higher in the alveolar lumen and septae but lower in the bronchial lumen and epithelium at 6 hours PI than at 2 hours PI. Significantly fewer neutrophils (P < 0.05) were present in the alveolar lumen and septae, and the bronchiolar lumen and lamina propria in the lungs of TBC1269-treated calves compared with untreated calves at 6 hours PI. TBC1269 did not alter the infiltration into bronchi and blood vessels or the expression of the selectin-independent adhesion molecule, ICAM-1. This work suggests that during acute pneumonia of neonates 1) neutrophil infiltrates progressively increase in the alveolar lumens and septae but decrease in the bronchial lumen and epithelium with time, 2) TBC1269 reduces neutrophil infiltration into specific regions of alveoli and bronchioles rather than uniformly throughout the lung, and 3) selectin inhibition does not affect the location and intensity of ICAM-1 expression.     

Surgical resolution of accidental intramuscular injection of Gudair® vaccine in a mare

This case report describes the accidental intramuscular administration of 20 mL Gudair® vaccine to a 7‐year‐old Standardbred mare and successful treatment of the resulting inflammatory reaction by radical surgical resection.     

Lunar surface magnetic fields and their interaction with the solar wind: results from lunar prospector

The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system.     

Knowledge and attitudes of Australian livestock producers concerning biosecurity practices

Biosecurity risks are a major threat to the profitability of the industry as well as impacting human and animal health. Livestock producers play a crucial role in biosecurity as the first to notice changes in the health or productivity of their stock and are generally responsible for implementing protective measures. However, uptake of biosecurity measures by producers is variable. We critically appraised the current literature regarding biosecurity practices in Australian livestock industries and highlight aspects that are well understood as well as those where further research or information is needed. Findings from 12 cross-sectional studies suggest that Australian producers' knowledge of biosecurity methods and importance might have a positive influence on their willingness to implement or incorporate biosecurity practices. There is moderate evidence supportive of biosecurity being well understood by livestock producers across Australia. Barriers to producers using biosecurity practices included lack of information or communication from agricultural, veterinary or government organisations. It was found that larger stock numbers were positively correlated with biosecurity implementation and that producers used veterinarians, government and industry agencies as resources for trusted information.     

Application of high-resolution melt curve analysis for classification of infectious bronchitis viruses in field specimens

Objective A real-time polymerase chain reaction (PCR)/high-resolution melt (HRM) curve analysis protocol was developed in our laboratory to differentiate infectious bronchitis (IB) virus reference strains. In the current study, this method was used to detect and classify IB viruses in field submissions. Procedure Over an 11-month period samples from 40 cases of suspected IB virus were received and 17 submissions were positive for IB virus by polymerase chain reaction. HRM curve analysis classified each strain as subgroup 1, 2 or 3 strain (12 submissions) or a strain that was unable to be classified (5 submissions). The 3′ untranslated region (UTR) and partial S1 gene nucleotide sequences for the 17 IB virus strains were determined and their identity with those of the relative reference strains compared to confirm the classifications generated using the HRM curve analysis. Results Of the 12 IB field viruses classified as subgroup 1, 2, or 3 using HRM curve analysis, the 3′UTR and S1 gene nucleotide sequences had identities ≥99% with the respective subgroup reference strain. Analysis of the 3′ UTR and S1 gene nucleotide sequences for the five IB virus strains that could not be classified indicated that four belonged to one of the subgroups, and one was a potential recombinant strain (between strains from subgroups 2 and 3). A novel recombinant strain was also detected. Conclusion HRM curve analysis can rapidly assign the majority of IB viruses present in field submissions to known subgroups. Importantly, HRM curve analysis also identified variant genotypes that require further investigation.