Effectiveness of Gudair™ vaccine for the control of ovine Johne's disease in flocks vaccinating for at least 5 years     

PA Windsor  J Eppleston  NK Dhand  RJ Whittington 《Australian veterinary journal》2014,92(7):263-268

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The Effect of the Intracervical Application of Follicle‐Stimulating Hormone or Luteinizing Hormone on the Pattern of Expression of Gonadotrophin Receptors in the Cervix of Non‐Pregnant Ewes     

S Leethongdee  M Khalid  RJ Scaramuzzi 《Reproduction in domestic animals》2014,49(4):568-575

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Genotypic diversity in field isolates of Babesia bovis from cattle with babesiosis after vaccination     

AE LEW  RE BOCK  JM CROFT  CM MINCHIN  TG KINGSTON  RJ DALGLIESH 《Australian veterinary journal》1997,75(8):575-578

Objective To determine whether particular genotypes of Babesia bovis were common to field isolates obtained from cattle properties in Queensland where the B bovis vaccine had apparently failed.
Design A comparative study of polymerase chain reaction genotypes in different populations of B bovis .
Procedure Two polymerase chain reaction assays were applied to analyse DNA extracts of B bovis vaccine (K, T and Dixie strains) and 27 field isolates from 24 properties where disease outbreaks had occurred despite the use of the vaccine. To evaluate the stability of the genotypes identified, 11 of the field isolates were inoculated into experimental cattle that had either been previously vaccinated with T strain or not vaccinated.
Results No particular genotype of B bovis was responsible for the problems observed in previously vaccinated herds. None of the isolates had genotypes identical to the vaccine strains used. No geographic trends among the genotypes were observed. Isolates that originated from the same property also had different genotypes. Blood passage of the 11 field isolates in either previously vaccinated or nonvaccinated cattle did not alter the original genotype.
Conclusion No particular genotypes identified by the Bv80 and BvVA1 polymerase chain reaction assays could be associated with vaccine failures.  相似文献   

Does fisheries management reflect societal values? Contingent Valuation evidence for the River Murray     

D.L. BAKER  & B.E. PIERCE 《Fisheries Management and Ecology》1997,4(1):1-15

Non-use value is likely to be a significant component of the total societal value of a fishery, but is rarely quantified and is not explicitly considered in most management structures. Contingent Valuation Methodology (Willingness-to-Pay approach) was employed to obtain estimates of the value of the lower River Murray fishery recreational and non-consumptive sectors relative to the commercial sector. Respective estimates of $A9.6 m, $A45.2 m and $A1.1 m per annum indicate the importance of considering non-use values in fisheries management. A parallel Willingness-to-Accept approach provided estimates of fishery value 8–15 times greater than the Willingness-to-Pay estimates. Analysis of the independent variables (age, sex, location of home residence, whether or not the respondent was a recreational angler and whether or not the respondent was a recreational angler on the River Murray) relative to the dependent Willingness-to-Pay estimates, revealed that the only significant explanatory variable was whether the respondent fished recreationally in this fishery. It is argued that management structure should first reflect societal values before the effectiveness of management strategies or individual mechanisms can be meaningfully assessed.  相似文献   

Postmortem lesions in the intercarpal ligaments of the equine midcarpal joint     

RC WHITTON  RJ ROSE 《Australian veterinary journal》1997,75(10):746-750

Objective To determine the frequency of damage to the medial palmar intercarpal ligament (MPICL), and the range of sizes of the dorsomedial intercarpal ligament (DMICL) of the midcarpal joint in horses with no history of carpal joint disease.
Materials and methods
Cadaver limbs were collected from 72 horses with no history of carpal joint disease. One hundred and forty-two midcarpal joints were dissected and the MPICL and DMICL were examined. Measurements were made with a digital micrometer.
Results MPICL tearing was present in 88 of 96 joints from horses 2 years and older. Tears were predominantly of the dorsolateral bundle and complete rupture of the dorsolateral and dorsomedial bundles was not observed. Tearing was not present in foals less than 4 months of age and the severity of tearing increased significantly with age (P < 0.0001). Severity of tearing was significantly greater in racing Standardbreds than racing Thoroughbreds (P < 0.01), but there was no significant difference between racing and non-racing horses. The lateromedial thickness of the DMICL ranged from 0.4 mm to 2.6 mm in horses 2 years and older. Lateromedial thickness increased significantly with age, and was significantly greater in racing Standardbreds than racing Thoroughbreds (P < 0.01). There was no significant difference between racing and nonracing horses.
Conclusions Damage confined to the dorsolateral bundle of the MPICL is a common finding in horses over 1 year of age and is probably of little clinical significance. Complete rupture of both dorsolateral and dorsomedial bundles is uncommon in horses with no history of midcarpal joint disease. Variation in size of the DMICL is observed in horses of all ages, but is most marked in 2-year-old horses.  相似文献   

The Battle against Skill Obsolescence     

W. PIERCE LILES 《Growth and change》1972,3(2):16-22

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不同水分条件下施用稻草对土壤有机酸和有效磷的影响   总被引：12，自引：1，他引：12       下载免费PDF全文

彭娜  王凯荣  Buresh RJ  王开峰  谢小立 《土壤学报》2006,43(2):347-351

稻草在分解过程中产生有机酸。高浓度的有机酸一方面对水稻生长产生毒害作用，另一方面，有机酸可通过酸溶、螯合和竞争吸附等机制活化土壤难溶态磷，提高磷的生物有效性。所以，研究稻草分解过程中有机酸和有效磷的动态变化，对于评价稻草还田在水稻营养中的作用，指导秸秆管理具有十分重要的意义。  相似文献   

Investigations into the toxicity of Echium plantagineum in sheep: 2. Pen feeding experiments     

JT SEAMAN  RJ DIXON† 《Australian veterinary journal》1989,66(9):286-292

In a pen feeding trial fresh Echium plantagineum was fed as the sole diet to crossbred sheep with or without a history of previous access to the plant. Control groups received a diet of lucerne chaff and oats. During the trial, sheep on the Echium diet lost weight and deaths occurred with histological evidence of excessive copper accumulation, usually accompanied by pyrrolizidine alkaloid damage, in the liver and biochemical evidence of liver toxicity. It is concluded that E. plantagineum alone is not a suitable fodder for sheep and can be toxic due to its pyrrolizidine alkaloid content and high copper to molybdenum ratio.  相似文献   

Lithospheric Contributions to Arc Magmatism: Isotope Variations Along Strike in Volcanoes of Honshu, Japan     

AB Kersting  RJ Arculus  DA Gust 《Science (New York, N.Y.)》1996,272(5267):1464-1468

Major chemical exchange between the crust and mantle occurs in subduction zone environments, profoundly affecting the chemical evolution of Earth. The relative contributions of the subducting slab, mantle wedge, and arc lithosphere to the generation of island arc magmas, and ultimately new continental crust, are controversial. Isotopic data for lavas from a transect of volcanoes in a single arc segment of northern Honshu, Japan, have distinct variations coincident with changes in crustal lithology. These data imply that the relatively thin crustal lithosphere is an active geochemical filter for all traversing magmas and is responsible for significant modification of primary mantle melts.  相似文献   

Effect of a second treatment of prostaglandin F2α during the Ovsynch program on fixed-time artificial insemination conception rates and luteolysis in split-calving,pasture-fed dairy cows     

JM Rheinberger  DD Colson  DS Beggs  PD Mansell  MA Stevenson  RJ Rheinberger  MF Pyman 《Australian veterinary journal》2020,98(5):190-196

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