NUCLEATION,POLYMERIZATION, AND PRECIPITATION OF FeOOH1     

PA HO HSU 《European Journal of Soil Science》1972,23(4):409-419

Fresh Fe(ClO₄)₃ solutions, 0.01 M or 0.001 M in iron (III), were seeded with iron (III) hydroxide brown sols and the reaction processes were investigated. In two experiments, HC1O₄ was added to fresh Fe(ClO₄)₃ solutions to lower their degrees of super saturation with respect to iron (III) hydroxide. Depending upon the quantity of seeding solution added, it was found that samples differed greatly in appearance and in the stability during ageing. With a small amount of seeding solution added and following a relatively long induction period, the sample rapidly developed to a dense, cloudy yellow suspension with FeOOH precipitate settled shortly afterwards. With an increased amount of seeding solution added, the sample gradually became more brownish and less turbid and eventually a clear brown sol was observed. Although α-FeOOH was the major hydrolysed species in all samples, a yellow precipitate which settled under gravity was found only in those containing a small quantity of seeding solution. The above results provide experimental evidence supporting the hypothesis (Hsu and Ragone, 1972) that the initial number of nuclei relative to the concentration of mono-meric species is the key factor governing the appearance and the stability of an hydrolysed iron (III) solution. In another experiment, varying amounts of a seeding solution were added to a fresh, pure 0.001 M Fe(ClO₄)₃ solution to which no HC1O₄ was added. All samples rapidly hydrolysed to clear brown sols in less than 6 hours and no noticeable seeding effect was observed. It is suggested that a pure 0.001 M Fe(ClO₄)₃ solution is highly supersaturated with respect to iron (III) hydroxide and a large number of nuclei spontaneously form in situ shortly after preparation.  相似文献   

Lesions in sheep following administration of a vaccine of a Freund's complete adjuvant nature used in the control of ovine paratuberculosis     

PA Windsor  J Eppleston 《New Zealand veterinary journal》2013,61(5):237-241

CASE HISTORIES: Occurrences of adverse reactions in seven sheep flocks in Australia following vaccination against paratuberculosis where veterinary attention was requested are reviewed. All cases occurred within the 3-year period following commencement of use of a vaccine of a Freund's complete adjuvant nature, at a time when approximately six million doses of vaccine had been administered.

CLINICAL FINDINGS: In the first case, 26/58 (45%) Merino sheep vaccinated as adults had palpable tissue reactions at or near the site of vaccination; enlarged prescapular lymph nodes were palpated in 17 (29%), and nine (16%) sheep had both palpable lesions at the site of vaccination and enlarged prescapular lymph nodes. The reactions included caseous nodules up to 5.5 cm in diameter. In the other cases, fistulating or granulomatous wounds were occasionally found at the recommended site of injection behind the ear, and myiasis was rare. Occurrences of inappropriate choice of injection site were recorded, including injection into the axilla of two Merino rams, and lesions in the tissues of the maxilla and nose of almost 50% of 350 Border Leicester lambs. Four outbreaks of progressive paralysis due to injection into cervical musculature were reported, described as ‘OJD staggers’ by producers.

DIAGNOSIS: Granulomatous cellulitis and lymphadenitis associated with oil droplets typical of ‘oil granulomata’. Injection of vaccine into the dorsal cervical area resulted in progressive paralysis due to myonecrosis and suspected granulomatous leptomeningitis.

CLINICAL RELEVANCE AND CONCLUSIONS: Although lesions at and near the site of injection are common, adverse reactions to vaccination were rare and included mortality from cervical spinal injection, production losses from injection in the maxilla or axilla or if myiasis resulted, and potential marketing losses if animals or carcasses are discounted as a result of the lesions. Risk factors for adverse reactions included inadequate restraint of sheep, breed of sheep, experience of the operator, poor injection technique, and inappropriate placement of vaccine. Increasing attention to the proper restraint of animals, restricting vaccination to the recommended site behind the ear, careful placement of the vaccine into subcutaneous tissue to avoid drainage of vaccine material into tissues such as the spinal cord, and post-vaccination supervision to address welfare concerns should adverse reactions occur are recommended.  相似文献   

Neurological diseases of ruminant livestock in Australia. III: bacterial and protozoal infections     

AE Kessell  JW Finnie  PA Windsor 《Australian veterinary journal》2011,89(8):289-296

Bacteria (including chlamydia) and protozoa can produce neurological disease in Australian ruminant livestock and the nature of the inflammatory and neuroparenchymal response is often suggestive of a particular aetiological agent. An overview of the clinicopathological features of infectious disease affecting the central nervous system (CNS) is followed by a discussion of important bacterial and protozoal infections in Australia. Each infectious disease is discussed in terms of classification and pathogenesis linked to clinical signs and gross and microscopic findings. The literature review is restricted to infectious conditions causing CNS disease in Australia. Sources include the Australian Veterinary Journal (over 50 years of articles), the quarterly newsletter of the National Animal Health Surveillance System and the Animal Health Surveillance Quarterly.  相似文献   

Musculoskeletal disorders and psychosocial risk factors among veterinarians in Queensland, Australia   总被引：1，自引：1，他引：0  

DR Smith  PA Leggat  R Speare 《Australian veterinary journal》2009,87(7):260-265

Objective   Although musculoskeletal disorders (MSD) represent one of the most important occupational health issues in contemporary society, few studies have specifically investigated this problem among veterinarians.
Design   An anonymous questionnaire survey mailed to all veterinarians registered with the Veterinary Surgeons Board of Queensland during 2006.
Results   Almost two-thirds of respondents (63%) had experienced MSD of the lower back, 57% had experienced neck-related MSD, 52% had experienced shoulder-related MSD and 34% had experienced MSD of the upper back during the previous 12 months. MSD was statistically correlated with a range of psychosocial factors, including stress associated with career structure, time pressures, client's attitude, lack of recognition by the public, lack of recognition by colleagues, lack of understanding from family or partners and work stress because of insufficient holidays each year.
Conclusion   Overall, this study has demonstrated significant correlations between MSD and psychosocial risk factors among a large cohort of veterinarians, apparently for the first time in the published literature. The results also suggest that personal and workplace issues may contribute more to the development of MSD among veterinarians than many of the previously recognised ergonomic risk factors.  相似文献   

Clinical review of two fatal equine cases of infection with the insectivorous bat strain of Australian bat lyssavirus     

EJ Annand  PA Reid 《Australian veterinary journal》2014,92(9):324-332

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Chondrodysplasia in Australian Dexter cattle   总被引：1，自引：0，他引：1  

PAW HARPER  MR LATTER  FW NICHOLAS  RW COOK  PA GILL 《Australian veterinary journal》1998,76(3):199-202

Objective To describe the occurrence of chondrodysplasia in Australian Dexter cattle.
Design A pathological and genetic case report.
Procedure Congenital lethal chondrodysplasia was studied in two female Dexter foetuses aborted mid to late gestation. Clinicopathological findings including histological changes in limb bones, and analysis of pedigree information were evaluated.
Results Characteristic features of congenital lethal chon-drodysplasia (Dexter bulldog) include abortion, disproportionate dwarfism, a short vertebral column, marked micromelia, a relatively large head with retruded muzzle, cleft palate and protruding tongue and a large abdominal hernia. Histological changes in limb bones are consistent with failure of endochondral ossification. Dexter chondrodysplasia is considered to be inherited in an incompletely dominant manner with the homozygous form producing the congenital lethal condition. A preliminary minimum estimate of heterozy-gote frequency is 19% within the registered Australian Dexter herd, based on analysis of the contribution of three obligate heterozygotes whose semen has been widely used by artificial insemination in Australia.
Conclusion Dexter chondrodysplasia is present in Australian cattle and further cases of the homozygous form, congenital lethal chondrodysplasia, are likely to occur.
Recommendation It is requested that spleen and liver tissue from bulldog foetuses and blood from their parents be collected to assist research into Dexter chondrodysplasia.  相似文献   

Thiamethoxam and imidacloprid drench applications on sweet orange nursery trees disrupt the feeding and settling behaviour of Diaphorina citri (Hemiptera: Liviidae)          下载免费PDF全文

Marcelo P Miranda  Pedro T Yamamoto  Rafael B Garcia  João PA Lopes  João RS Lopes 《Pest management science》2016,72(9):1785-1793

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Refractory otitis media and otitis externa in a koala (Phascolarctos cinereus) treated with total ear canal ablation and lateral bulla osteotomy     

MJ Swaffield  M Liberts  AK Gillett  PA Moses 《Australian veterinary journal》2023,101(11):440-444

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Urinary catheterisation of female dogs: a comparison between three techniques for catheter placement     

AE Tipler  EA Moses  R Greer  P Delisser  BD McCracken  PA Moses 《Australian veterinary journal》2020,98(8):364-370

The objective of this study was to describe a new technique for urinary catheterisation of female dogs using a novel catheterisation device (NCD) and to compare the time taken to place a catheter using this technique with traditional techniques. A secondary objective was to survey participants on which of the techniques they preferred. Female canine cadavers of varying sizes were utilised and veterinary students who had not previously placed a urinary catheter were enrolled. Each participant performed three catheterisation techniques, Visual with speculum (SPEC), Blind Palpation (BP) and catheterisation with NCD on three sizes of dog. Time required using each technique was compared using Kaplan–Meier plots and mixed models Cox Proportional Hazards regression. Median times to catheterisation were 300 s (IQR 261–417 s) with the SPEC method, 420 s (IQR 253–545 s) with the NCD method and 725 s (574–1032s) with the BP method. Both SPEC and NCD methods were significantly faster compared to the BP method, with Hazard Ratios of 3.66 (95% CI 1.94–6.91, P < 0.001) and 3.57 (95% CI 1.87–6.81, P < 0.001), respectively. Six of nine participants found the NCD the easiest technique, 5/9 of the participants found the palpation technique most difficult and 4/9 found the speculum technique most difficult. BP appears to be the technique of least preference and increased time requirement. The novel urinary catheterisation device may provide a simpler method of visualisation of the urethral papilla and may provide a more sterile way of placing the catheter, although further investigation is needed to confirm this.  相似文献   

Neurological diseases of ruminant livestock in Australia. II: toxic disorders and nutritional deficiencies     

JW Finnie  PA Windsor  AE Kessell 《Australian veterinary journal》2011,89(7):247-253

The second in this series of clinical reviews on neurological diseases in ruminant livestock in Australia examines toxic disorders associated with plant and microbial toxins as well as the neurological effects of vitamin and mineral deficiencies. The aim of these reviews is to assist in the surveillance of neurological diseases, especially the transmissible spongiform encephalopathies.  相似文献