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771.
J Romatowski 《Journal of the American Veterinary Medical Association》1989,195(7):928-930
Routine prevaccinal screening for FeLV has inherent statistical limitations owing to the magnification of false-positive test errors by the low prevalence of FeLV viremia in the general cat population. Positive ELISA test results obtained in a screening program should be interpreted with caution, because a high proportion--approximately 72%--of such are likely to be false-positive results. On the other hand, routine screening is an excellent method for ruling out FeLV viremia, because a false-negative result is likely to be obtained in only 1/1,000 tests. 相似文献
772.
773.
G. B. J. Chapola 《Wood Science and Technology》1989,23(2):131-138
Summary The aim of this study was to investigate the influence of temperature, alkali and cement set on the visco-elastic properties of chip mattresses made in cement and calcium hydroxide, respectively. Two temperatures were used, room temperature and 78°C, believed to represent the limits of the range of temperatures experienced industrially in the manufacture of cement composites. Calcium hydroxide and cement were used to find the effect of alkali and the effect of cement set. The temperature affected the visco-elastic properties by increasing the unrecovered strain, and alkali also increased the unrecoverable strain. The effect of heat and alkali increased when the two were used in combination. In cement chip composites, the effect of cement set was the most dominant that the effect of heat and alkali could not be observed.I am indebted to Dr. A. J. Bolton of the University College of North Wales, Bangor, for his assistance. This study was carried out at this university as an Honours Project 相似文献
774.
Age at death from natural scrapie in a flock of Suffolk sheep 总被引:1,自引:0,他引:1
This study deals with natural scrapie in a flock of Suffolk sheep being bred to maximise the incidence of the disease and shows that with succeeding generations the incubation period of the disease became progressively shorter until the flock died out. The most likely explanation for this phenomenon is considered to be an increase in the load of infection. 相似文献
775.
The kidney's microvascularization of the Pudu pudu is mostly similar to that of domestic animals. The renal parenchymatous arteries do not give off capsular branches. The majority of the Pudu pudu's glomerula shows spherical shape. Glomerula next to the medulla have a diameter which is an average of 25 microns larger than the diameter of those situated more peripherally. Their volume is comparable to that of the angora rabbit. The capillaries form anastomosis in the inner and outer part of the glomerulus. 相似文献
776.
Residual ovine nematode pasture infections were assessed by grazing groups of ewes and their lambs on permanent sheep and cattle pastures and by the use of tracer lambs. Ostertagia spp., Cooperia oncophora, Nematodirus spp., Chabertia ovina and Trichuris spp. eggs and/or larvae survived on pastures overwinter. Second generation Ostertagia larvae were present in greatest numbers on pasture during the latter part of August and early September. The failure of a significant build-up of Cooperia oncophora was attributed to negligible worm egg output of this species in sheep. A build-up of Nematodirus spp. on pasture was not detected in this study. 相似文献
777.
778.
M G Davidson E B Breitschwerdt M P Nasisse S M Roberts 《Journal of the American Veterinary Medical Association》1989,194(6):777-781
Dogs were examined ophthalmoscopically to determine the prevalence and type of ocular lesions associated with naturally acquired Rocky Mountain spotted fever (RMSF). In a consecutive series of 11 dogs with serologically confirmed RMSF, 9 had ocular involvement reflecting various degrees of vascular damage, including subconjunctival hemorrhage, hyphema, anterior uveitis, iris stromal hemorrhage, retinal petechiae, and focal areas of retinal edema and perivascular inflammatory cell infiltrate. The ophthalmic lesions generally were mild, and most resolved without complication after systemic administration of appropriate antibiotics. The high prevalence of ocular lesions in these dogs suggested that critical ophthalmologic evaluation is a useful diagnostic tool for the early detection and management of RMSF in dogs. 相似文献
779.
We studied the ability of lambs to select safe foods in the presence of harmful foods. In a series of feeding experiments, 3- to 6-mo-old lambs were offered a choice between 1) a familiar, safe and a novel, harmful food, 2) a novel, safe and a novel, harmful food and 3) a familiar, harmful and a novel, safe food. All harmful foods were palatable feeds that had been treated with lithium chloride (LiCl), a non-lethal gastrointestinal poison. When lambs ingested a meal composed of a novel food containing LiCl and a familiar, safe food, lambs subsequently avoided the novel food. Lambs avoided the novel food even when the familiar food contained LiCl. The response of lambs varied when lambs were given a choice between a novel, safe food and a novel food containing LiCl. Lambs either avoided the novel food containing LiCl and ingested the safe food or they limited their intake of both novel foods. Their response was dependent on the novelty of the food containing LiCl. When a novel, palatable food contained 2% LiCl, lambs always ate some of the food, even after experiencing illness from ingesting it. Lambs experienced with foods containing LiCl displayed greater food neophobia than lambs naive to LiCl-treated foods. Thus, novelty was the major criterion that lambs used to associate foods with gastrointestinal illness. 相似文献
780.
W. M. PEDERSOLI J. S. SPANO L. M. KRISTA.† J. F. WHITESIDES.† W. R. RAVISH‡ R.J. KEMPPAINEN D. W. YOUNG 《Journal of veterinary pharmacology and therapeutics》1989,12(2):200-208
The effects of single i.v. and p.o. doses (5 mg/kg) of fenbendazole, were evaluated on thyroxine, tri-iodothyronine, corticosterone, hematology, clinical chemistries, and serum proteins in 10 white Pekin ducks. Fenbendazole was administered i.v. (n = 5) as a 3% dimethyl sulfoxide solution and p.o. (n = 5) as a 10% commercial suspension. Serum enzyme concentrations, total protein and protein fractions, glucose, cholesterol, uric acid, sodium, and potassium were unchanged from baseline values. Serum triglycerides decreased consistently in the i.v.-treated group but remained unchanged in the p.o.-treated group. Serum chloride was consistently elevated above baseline values for both i.v.- and p.o.-treated ducks, while inorganic phosphate was consistently decreased only in the i.v.-treated group. Hemoglobin and hematocrit values generally were below baseline values. Leukocyte values varied considerably and were not significantly different from baseline values. Serum thyroxine and tri-iodothyronine values in both the i.v.- and p.o.-treated groups were not changed significantly from baseline values. Serum corticosterone values were not changed in the i.v.-treated groups but they were decreased at various times in the p.o.-treated group. Although there were some sporadic significant changes in the parameters measured versus baseline values all values remained within the physiologic limits for ducks. The safety of fenbendazole has been previously demonstrated for several species. 相似文献