Investigation of Johne's disease in Tasmanian fallow deer (Dama dama)     

RB Jackson  DJ Kennedy  ESG Sergeant 《Australian veterinary journal》2021,99(1-2):44-45

In 2012 when many sheep flocks in northern‐central Tasmania were experiencing a high prevalence of ovine Johne's disease, 34 wild adult fallow deer shot on or near infected properties were negative to microscopic Mptb lesions of the ileo‐caecal valve, terminal ileum and ileo‐caecal lymph nodes. This study demonstrated 95% confidence of detecting Johne's disease in this fallow deer population if ≥10% of animals were shedding Mycobacterium avium subsp. paratuberculosis in their faeces, or if ≥21% of animals were sub‐clinically infected.  相似文献   

Chemical and biological trends associated with acidic atmospheric deposition in the Rhode River watershed and estuary     

David L. Correll  Joseph J. Miklas  Anson H. Hines  James J. Schafer 《Water, air, and soil pollution》1987,35(1-2):63-86

The Rhode River estuarine/watershed system is a tributary of Chesapeake Bay located on the inner Atlantic Coastal Plain. Its soils are fine sandy loams. Bulk precipitation pH in the spring season declined from 4.95 in 1974 to 3.82 in 1981 and was 4.03 in 1985. The changes in pH of a forested primary stream were more related to changes in bulk precipitation pH than were the changes in pH of agricultural streams, reflecting the importance of other major terrestrial sources of acidity on agricultural systems. Surges in acidity and dissolved total Al concentration in primary (first order) streams reached extremes of pH 3.2 and 300 μg Al L^?1. Higher order streams were observed to have surges in acidity with pH minima below 5.0. Surges in acidity ocurred during accelerated groundwater percolation following storm events and did not coincide with surface runoff or snowmelt. One of the reasons why groundwater is more acidic than surface runoff is that the vegetation exchanges H30 ⁺ for alkaline cations in the soil and translocates these ions to the vegetational canopy. When it rains, subsequently, H₃0⁺ in the precipitation displace some of these alkaline cations from the canopy. The end result is that overland flow during storms is enriched in alkaline cations, while groundwater is enriched in H₃0⁺. Although the source of dissolved Al is dissolution of clay minerals with atomic ratios of Al to silicate of 1:l, 1:2, or 1:3, this ratio in stream water rapidly declined to 1:1200 due to loss of Al. On average, forest drainage was the most acidic, the highest in dissolved Al, and the lowest in Ca. Surges in acidity were most severe from pastureland, and next most severe from cropland. Total fluoride concentrations were high relative to Al from all three land uses. Rhode River spawning runs of Perca flavescens declined drastically from the early 1970s to essentially zero since 1981. Larval bioassays of acidity indicate negligible toxicity to Hyla crucifer, significant toxicity to Perca flavescens and drastic effects on Morone saxatilis at pH 5.0.  相似文献   

Retrospective analysis of 736 cases of canine gastric dilatation volvulus     

KK Song  SE Goldsmid  J Lee  DJ Simpson 《Australian veterinary journal》2020,98(6):232-238

  相似文献   

Echinococcus granulosus in the Northern Territory,Australia: hydatid disease reported in beef cattle from the region     

CS Wilson  VJ Brookes  DJ Jenkins 《Australian veterinary journal》2020,98(3):100-102

Hydatid disease in beef cattle has been reported to be widespread throughout Australia, but cattle bred and raised in the Northern Territory were previously believed to be free of the disease. Between 2010 and 2016, 1061 cattle from the Northern Territory were slaughtered at a New South Wales abattoir and inspected for hydatid disease. The proportion of cattle reported infected with hydatid disease was 3.5%. Individual cattle identification numbers indicated that the cattle included in the study had most likely remained within the Northern Territory from birth until immediately prior to slaughter, so were assumed to have become infected within the region. We suspect that the sylvatic cycle of Echinococcus granulosus transmission could be responsible for infection of cattle in this region.  相似文献   

Risk factors associated with the occurrence of swine dysentery in Western Australia: results of a postal survey     

ID ROBERTSON  JRL MHOMA  DJ HAMPSON 《Australian veterinary journal》1992,69(4):92-93

  相似文献   

Resistance of Fasciola hepatica to triclabendazole   总被引：1，自引：0，他引：1  

DJ OVEREND  FL BOWEN 《Australian veterinary journal》1995,72(7):275-276

  相似文献   

Preulcerative changes to the pars oesophagea associated with Torulopsis glabrata infection in a weaned pig     

DJ. McGILLIVERY 《Australian veterinary journal》1989,66(10):337-338

  相似文献   

The characteristics and causes of sheep losses in the Victorian Mallee     

DJ HARRIS  G. NOWARA† 《Australian veterinary journal》1995,72(9):331-340

SUMMARY The extent and causes of sheep losses in the semi-arid Mallee region of north-western Victoria were assessed by interviewing the owners of 79 randomly selected farms running 241 flocks in 1987/88 and 245 flocks in 1988/89. Mean annual losses were higher in ram flocks (21%) than in ewe flocks (7%), in flocks of non-Merino sheep (rams 24%, ewes 11%, weaners 5%) than in Merino (rams 11%, ewes 6%, wethers 4%, weaners 4%) and in ewe flocks 3 or more years old (10%) than in young ewe flocks (3.5%). In flocks where losses exceeded 5%, the causes most often reported by farmers were blowfly strike (especially in Merino sheep and weaners), ewe losses in autumn close to lambing, and heliotrope (Heliotropium europaeum) poisoning. Heliotrope poisoning was considered by the authors to be the main reason for the higher losses in old ewes than in young ewes and in non-Merino sheep than in Merino sheep. Losses of ewes associated with pregnancy and lambing were considered by the authors to be often predisposed by liver damage caused by heliotrope poisoning, and high losses in non-Merino ram flocks were attributed to both heliotrope poisoning and their ability to escape through boundary fences. Reasons for continuing high losses due to enterotoxaemia are discussed. Losses due to gastro-intestinal parasites, footrot and foot abscess were low.  相似文献   

Failure to detect antibody to turkey rhinotracheitis virus in Australian poultry flocks     

IG BELL  DJ ALEXANDER 《Australian veterinary journal》1990,67(6):232-233

  相似文献   

The effects of antigenic competition on the efficacy of multivalent footrot vaccines     

CL SCHWARTZKOFF  JR EGERTON†  DJ STEWART‡  PR LEHRBACH§  TC ELLEMAN¶  PA HOYNE¶ 《Australian veterinary journal》1993,70(4):123-126

SUMMARY A multivalent footrot vaccine has been developed, containing pilus antigens produced in recombinant Pseudomonas aeruginosa and representing all nine serogroups of Dichelobacter (Bacteroides) nodosus commonly recognised in the field. The responses of sheep to the multivalent vaccine have been compared with those to monovalent vaccines representing only a single serogroup. Antigenie competition between serogroups occurred in sheep immunised with the multivalent formulation, but high levels of protection were still achieved. The study showed that in multivalent footrot vaccines, antigenic competition is predominantly due to the presence of a family of immunologically-related pilus antigens rather than to interference by extraneous proteins.  相似文献