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1.
Six bullmastiffs with congenital heart disease were evaluated over a three-year period. In all the cases the problem was shown to be dysplasia of the pulmonary valve. Five cases were male, one was female. All dogs available to follow-up developed signs of cardiac decompensation. Bullmastiffs must be added to the list of breeds in which valvular pulmonic stenosis is encountered frequently.  相似文献   
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Infection with Fascioloides magna, the large American liver fluke, was diagnosed in two moose (Alces alces) and six wapiti (Cervus elaphus) from central Saskatchewan. This is believed to be the first record of the parasite in the province. Fecal samples collected from wild wapiti at five sites in the commercial forest zone in Saskatchewan contained eggs believed to be those of F. magna. Trematode eggs were not found in feces from five captive herds of wapiti in the province, nor in samples from wild wapiti in Moose Mountain Provincial Park. Operculate eggs were found in feces of wild wapiti from Cypress Hills, but these were believed to be from trematodes other than F. magna. The distribution and significance of F. magna in Canada, based partially on responses to a mail questionnaire, are reviewed.  相似文献   
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1. Automatic weighing equipment was tested on a flock of 752 roaster chickens reared on litter to 10 weeks of age.

2. Mean body weights obtained automatically were lower than those obtained manually, mainly because of birds perching on the automatic weighing perch with part of their body in contact with the floor.

3. Birds observed on the weighing perch on one day of the week were 3–5 times more likely to use the perch again on the following 2 d than expected on the basis of random perch use by flock members. These birds were also more likely to be seen in the area immediately surrounding the perch than in similar areas elsewhere in the pen.  相似文献   

4.
The intraindividual variability in mean electric axis referable to choice of ECG leads and augmentation ratio was investigated by means of a digital computer program. Although, in theory, the choice of leads for determining the QRS axis should make no difference, the maximum intraindividual variation in axis angle was about 50 degrees for canine and feline subjects. The angle conputed for the lead combinations I and III and I and aVF will usually fall within 5 to 10 degrees of the mean of all lead combinations, but larger variations are seen at time. The application of an "augmentation ratio" for the augmented unipolar leads was most helpful when it was individually computed. Further methods of lead-vector improvement are discussed.  相似文献   
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Plasma concentrations of PAG‐1 are used for pregnancy diagnosis and as a marker of placental/foetal well‐being, while those of PAG‐2 may be an indicator of abortion risk in Neospora caninum‐infected cows. Studies have shown that N. caninum infection modifies PAG‐1 and PAG‐2 patterns in maternal blood plasma. However, no prior work has examined the effects of N. caninum infection on concentrations of PAGs in foetal fluids. In this study, PAG‐1, PAG‐2 and pH levels were determined in the amniotic and allantoic fluids of foetuses collected at 152 days of gestation from control uninfected dams and from dams experimentally infected with N. caninum on Day 110 of gestation. Foetal fluids from infected foetuses had significantly higher PAG‐2 concentrations (p = 0.026) and pH values (p = 0.02) than fluids from non‐infected foetuses. In infected foetuses, significantly higher concentrations of PAG‐1 (p < 0.001) and PAG‐2 (p < 0.001) were detected in fluid samples showing antibodies against N. caninum than those without antibodies. Moreover, pH values were significantly higher (p = 0.011) in foetal fluid samples with antibodies than in samples from non‐infected foetuses. In conclusion, this is the first report on the effect of N. caninum infection on PAG levels in foetal fluids. Our results indicate that following the experimental infection of dams with N. caninum on Day 110 of gestation, foetal fluids collected from the infected foetuses of these dams featured higher PAG‐1 and PAG‐2 levels and pH values than fluids from non‐infected controls, provided that the samples tested showed the presence of antibodies. The clinical implications of these findings are that following infection with N. caninum, most cows will experience some level of placental damage and that this injury correlates with foetal fluid PAG levels and pH.  相似文献   
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Laterite profiles in the Sydney area are generally regarded as fossil soils, formed during the Miocene, on a peneplain, under a tropical climate. It is also held that subsequent uplift and dissection destroyed much of this surface together with the laterite profiles. These views are poorly established yet widely accepted. This study demonstrates that there is a very close mineralogic and stratigraphic relationship between the “laterite profiles” and the Triassic Hawkesbury Sandstone, such that the profiles are best regarded as iron rich sandstone units undergoing contemporary near-surface alteration including the mobilization of iron minerals as crystalline solids.  相似文献   
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