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11.
An investigation on the presence of larval cestodes in musk rats (Ondatra zibethicus) was carried out in two regions of the Netherlands (east Groningen and south Limburg) where in a earlier study foxes with Echinococcus multilocularis were found. A total of 1726 musk rats were dissected (1200 in Groningen, 526 in Limburg). Larval stages of Taenia taeniaeformis were most frequently found (total 44.8%: Groningen 42%, Limburg 51.3%), followed by T. martis (total 6.1%: Groningen 0.7%, Limburg 18.6%). Infections with T. crassiceps (total 0.3%: Groningen 0%, Limburg 1.0%), T. polyacantha (total 0.2%; Groningen 0.3%, Limburg 0%) and E. multilocularis (0.1%: Groningen 0.1%, Limburg 0%) were rare. Infections with T. taeniaeformis were more frequent in adults (71.8%) than in juveniles (34.2%). The same was found for T. martis: adults 15.3%, juveniles 2.5%. This difference was also reflected in the relation between weight of the animals and presence of infection. Heavier animals (>1000 g) were more often infected with T. taeniaeformis (74.1%) than animals less than 1000 g (34.8%). In musk rats weighing less than 500 g (n=155) only 5.2% were infected, but above 1200 g, 82.6%. The highest number of T. taeniaeformis was 28, of T. martis 13, of T. crassiceps >1000 and of T. polyacantha 24. The E. multilocularis was in a very young stage, a few white spots in the liver. Although E. multilocularis infections were exceptional, it is expected that with a rise in the number of infected foxes in the Netherlands the number of infected musk rats will increase. 相似文献
12.
Gould DH Dargatz DA Garry FB Hamar DW Ross PF 《Journal of the American Veterinary Medical Association》2002,221(5):673-677
OBJECTIVE: To analyze the sulfur content of water and forage samples from a geographically diverse sample of beef cow-calf operations in the United States and to estimate frequency and distribution of premises where forage and water resources could result in consumption of hazardous amounts of sulfur by cattle. DESIGN: Cross-sectional study. SAMPLE POPULATION: 709 forage samples from 678 beef cow-calf operations and individual water samples from 498 operations in 23 states. PROCEDURE: Sulfur content of forage samples and sulfate concentration of water samples were measured. Total sulfur intake was estimated for pairs of forage and water samples. RESULTS: Total sulfur intake was estimated for 454 pairs of forage and water samples. In general, highest forage sulfur contents did not coincide with highest water sulfate concentrations. Overall, 52 of the 454 (11.5%) sample pairs were estimated to yield total sulfur intake (as a percentage of dry matter) > or = 0.4%, assuming water intake during conditions of high ambient temperature. Most of these premises were in north-central (n = 19) or western (19) states. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that on numerous beef cow-calf operations throughout the United States, consumption of forage and water could result in excessively high sulfur intake. All water sources and dietary components should be evaluated when assessing total sulfur intake. Knowledge of total sulfur intake may be useful in reducing the risk of sulfur-associated health and performance problems in beef cattle. 相似文献
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14.
Sanchez J Dohoo I Nødtvedt A Keefe G Markham F Leslie K DesCôteaux L Campbell J 《Veterinary parasitology》2002,107(3):209-226
The general objective of this study was to evaluate a crude Ostertagia ostertagi antigen enzyme-linked immunosorbent assay (ELISA) for monitoring gastrointestinal parasites in lactating dairy cattle. A longitudinal study of gastrointestinal parasites in lactating dairy cows was carried out in 38 herds in four provinces of Canada (Prince Edward Island, Quebec, Ontario and Saskatchewan) from September 1999 to October 2000. Bulk tank milk, cow milk, serum and fecal samples were collected monthly or quarterly from all these farms. Information on herd management factors was collected by a standard questionnaire and individual cow production data were obtained from an electronic database. The overall mean optical density ratio (ODR) was 0.30 and ranged from -0.05 to 1.55. Although a clear seasonal pattern was not observed, the ODR values tended to decrease during the housing period and start increasing in the spring before the cows went out to pasture. The second and third or greater lactation cows had significantly higher ODR values compared with first lactation animals. The individual cow ODR had a very low correlation with individual squared root fecal egg counts but showed a reasonably high correlation when herd averages values were computed (r=0.73). A moderate correlation (r approximately 0.50) between the bulk tank and herd average ODR was observed. Milk yield was negatively associated with individual cow milk ODR and a quadratic effect on ODR was observed for days in milk. Twenty-eight of the herds participated in a clinical trial of eprinomectin (Ivomec Eprinex) treatment at calving. The cow level ODR values determined late in the previous lactation had a marginally significant effect (P=0.07) on treatment response, suggesting that high OD cows responded better to the anthelmintic treatment. However, because of the small sample size available in this model, more research is needed to better understand this relationship. In conclusion, the indirect ELISA using an O. ostertagi crude antigen appears useful as a technique for monitoring gastrointestinal parasite burdens in adult dairy cows and holds promise as a potential predictor of response to anthelmintic treatment. 相似文献
15.
Globoid cell leukodystrophy (GLD; Krabbe disease), is a rare heritable metabolic disorder in humans, dogs, mutant twitcher mice, and rhesus monkeys that is caused by a deficiency in the lysosomal enzyme galactocerebrosidase (GALC). GALC deficiency results in the accumulation of psychosine, which is toxic to oligodendrocytes and Schwann cells of the central and peripheral nervous systems. Clinical signs include hypotonia, mental regression, and death by 2 years of age in most human patients. Here we describe a domestic longhaired kitten with rapidly progressive neurologic disease and brain and spinal cord lesions characteristic of GLD. Pathologic hallmarks of the disease reflect the loss of oligodendrocytes and include myelin loss, gliosis, and the perivascular accumulation of large mononuclear cells with fine cytoplasmic vacuoles (globoid cells) in the peripheral and central nervous systems. Globoid cells were CD68 and ferritin positive, confirming their monocytic origin, and cytoplasmic contents were nonmetachromatic and periodic acid-Schiff positive. 相似文献
16.
Foster AP Sturgess CP Gould DJ Iwasaki T Day MJ 《The Journal of small animal practice》2000,41(6):266-270
A seven-year-old neutered male cocker spaniel was presented with an 11-month history of generalised bacterial dermatitis. There were skin lesions over the entire body, which were round, slightly raised and encrusted. Skin biopsies were collected and the histological findings were consistent with pemphigus foliaceus. Immunohistochemical staining by the indirect immunoperoxidase method was positive, with desmosomal deposition of immunoglobulin (Ig) G. Haematological analysis revealed a regenerative anaemia and profound thrombocytopenia, while a Coombs' test was positive for polyvalent canine Coombs' reagent and anti-dog IgG. An antinuclear antibody test was positive, with a titre of 10,240. An ophthalmic examination demonstrated low tear production (keratoconjunctivitis sicca). Seven months after initial referral, the dog was re-presented with severe generalised peripheral lymphadenopathy. Radiographic evaluation of the thorax and abdomen revealed enlarged cranial mediastinal and sublumbar lymph nodes. Tru-Cut biopsy from an enlarged lymph node confirmed the diagnosis of lymphoma, which was phenotyped as a B-cell tumour. The diagnosis in this case was systemic lupus erythematosus, with the unusual feature of pemphigus foliaceus, and subsequent development of B-cell lymphoma. The case adds further to knowledge of the protean clinical presentations of canine autoimmune diseases and provides additional evidence for the potential association between autoimmunity and immune-system neoplasia in this species. 相似文献
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18.
Cate E. Dewey W. Thomas Johnston Loriena Gould Terry L. Whiting 《Canadian journal of veterinary research》2006,70(3):161-167
A case-control study to investigate the contribution of postweaning multisystemic wasting syndrome (PMWS) and Porcine circovirus type 2 (PCV-2) to deaths among piglets of nursery age (19 to 68 d) in Manitoba indicated a significant positive association between PCV-2 infection and an increased mortality rate in nursery pigs. The clinical syndrome PMWS was seldom recognized in case or control herds; however, PCV-2 infection was widespread at the herd level. Other factors more strongly associated with increased piglet mortality rate than herd level PCV-2 infection were Mycoplasma hyopneumonia infection, porcine reproductive and respiratory syndrome (PRRS), and diarrhea caused by Eschericia coli K88. Management factors associated with case herd status included close proximity to other herds, larger number of sows supplying pigs to the nursery, larger range in age and weight going into the nursery, the moving of lightweight pigs into another nursery room at the end of the nursery fill, and not using spray-dried plasma in the 1st nursery ration. These results highlight the host-agent-environment triad leading to high nursery-barn mortality rates. 相似文献
19.
Yuri Zharikov David B. Lank Falk Huettmann Russell W. Bradley Nadine Parker Peggy P. -W. Yen Laura A. Mcfarlane-Tranquilla Fred Cooke 《Landscape Ecology》2006,21(1):107-120
We studied habitat selection and breeding success in marked populations of a protected seabird (family Alcidae), the marbled
murrelet (Brachyramphus marmoratus), in a relatively intact and a heavily logged old-growth forest landscape in south-western Canada. Murrelets used old-growth
fragments either proportionately to their size frequency distribution (intact) or they tended to nest in disproportionately
smaller fragments (logged). Multiple regression modelling showed that murrelet distribution could be explained by proximity
of nests to landscape features producing biotic and abiotic edge effects. Streams, steeper slopes and lower elevations were
selected in both landscapes, probably due to good nesting habitat conditions and easier access to nest sites. In the logged
landscape, the murrelets nested closer to recent clearcuts than would be expected. Proximity to the ocean was favoured in
the intact area. The models of habitat selection had satisfactory discriminatory ability in both landscapes. Breeding success
(probability of nest survival to the middle of the chick rearing period), inferred from nest attendance patterns by radio-tagged
parents, was modelled in the logged landscape. Survivorship was greater in areas with recent clearcuts and lower in areas
with much regrowth, i.e. it was positively correlated with recent habitat fragmentation. We conclude that marbled murrelets
can successfully breed in old-growth forests fragmented by logging. 相似文献