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排序方式: 共有273条查询结果,搜索用时 15 毫秒
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KURT C. VERCAUTEREN MICHAEL J. LAVELLE NATHAN W. SEWARD JUSTIN W. FISCHER GREGORY E. PHILLIPS 《The Journal of wildlife management》2007,71(5):1594-1602
Abstract: Direct and indirect contact between wild and farmed cervids along perimeter fences may play a role in transmission of diseases like chronic wasting disease (CWD), but no studies have quantified such interactions. At 9 high-fenced commercial elk (Cervus elaphus) farms in Colorado, USA, during October 2003 to January 2005, we used animal-activated video to estimate rates of fence-line use by wild cervids, rates of direct contact between farmed and wild cervids, and probability of direct contact when wild cervids were present. We recorded 8-fold-more wild elk per unit time than mule deer (Odocoileus hemionus) at fence lines. Depending on site, we recorded 0.66 to 46.90 wild elk per 1,000 hours of camera monitoring. We documented 77 interactions between wild and farmed elk involving naso-oral contact and no contact between wild mule deer and farmed elk. Rate of direct contact ranged from 0.00 to 1.92 direct contacts per 1,000 hours of camera monitoring among sites. Given recorded presence of wild elk, estimated probability of observing direct contact during a 2-minute video recording ranged from 0.00 to 0.11 among sites. Risk of direct contact was about 3.5 times greater for single woven-wire fence compared with offset electric fence attached to a single woven-wire fence. We observed no direct contact through double woven-wire fences. Because little is currently known about infection rates associated with infection mechanisms, we cannot infer a level of CWD infection risk from our results, but some form of double fencing should reduce potential for direct and indirect transmission of disease into or out of elk farms. 相似文献
3.
N. J. PHILLIPS 《Ibis》1987,129(1):10-24
During 1981–1983 the population of White-tailed Tropicbirds Phaethon lepturus at Cousin Island, Seychelles, bred aseasonally and asynchronously. The mean interval between consecutive successful breeding attempts was 273 days. Most individuals nested in the same site, and with the same partner, in successive attempts, but 7-5% of nest sites were used by more than one pair; 21 % of pairs which lost eggs, and 13% of those which lost chicks re-nested. Incubation lasted 40–41 days, with a mean incubation shift length of 6-6 days. Fledging periods varied between 67 and 89 days (mean 76-5 days). Mean fledging weight was not significantly greater than the average weight of breeding adults.
Fledging success was 36%. Many of the 39% of eggs which failed to hatch probably did so as a result of exposure to the sun's heat, following temporary desertion by adults which were themselves heat-stressed during incubation. Of the 41 % of chicks which died, most died young; many were probably killed by crabs Ocypode spp. Not more than 10% of all nest failures were due to nest site competition. A few chicks probably starved to death.
At the time of the study, both food and nesting sites were evidently in excess. A considerable increase in the size of the population will be possible before density-dependent control mechanisms begin to operate. 相似文献
Fledging success was 36%. Many of the 39% of eggs which failed to hatch probably did so as a result of exposure to the sun's heat, following temporary desertion by adults which were themselves heat-stressed during incubation. Of the 41 % of chicks which died, most died young; many were probably killed by crabs Ocypode spp. Not more than 10% of all nest failures were due to nest site competition. A few chicks probably starved to death.
At the time of the study, both food and nesting sites were evidently in excess. A considerable increase in the size of the population will be possible before density-dependent control mechanisms begin to operate. 相似文献
4.
Fine needle aspiration of the male breast can present problems of diagnosis because the cytological presentation of gynaecomastia can be confused with that of adenocarcinoma. We reviewed breast aspirates from 24 male patients in order to determine the accuracy of cytology as a method of diagnosing gynaecomastia. Discrepancies were observed between the original cytology reports on one hand and the review cytology and biopsies on the other. Of the 24 aspirates from the male breast, the cytology was reported as negative in 16 cases, suspicious in three cases and malignant in five. In four cases of the negative group, a specific diagnosis of gynaecomastia was made. In two of the negative cases the subsequent biopsies revealed adenocarcinoma. Of the five cases reported on the original cytology as adenocarcinoma, two on review showed the features of florid gynaecomastia and this was confirmed on biopsy and three confirmed the initial diagnosis of adenocarcinoma. The cytological features of gynaecomastia which distinguish it from adenocarcinoma are discussed. 相似文献
5.
A sporulation medium for Clostridium perfringens 总被引:2,自引:1,他引:1
K. D. PHILLIPS 《Letters in applied microbiology》1986,3(4):77-79
A new solidified medium for inducing sporulation of Clostridium perfringens is described. The essential components of the medium are bile, bicarbonate and quinoline. The medium induced significant sporulation in all of 100 strains of Cl. perfringens isolated at random from human faecal specimens. The majority (94%) of strains sporulated profusely. 相似文献
6.
Passive Haemagglutination Test for Anti-rhinovirus Antibodies 总被引:2,自引:0,他引:2
W. PAGE FAULK G. N. VYAS C. A. PHILLIPS H. HUGH FUDENBERG K. CHISM 《Nature: New biology》1971,231(21):101-104
The use of chromic chloride as a coupling reagent has made it possible to coat red cells with rhinovirus protein. This is shown by immunofluorescence, electron microscopy and immunocolloidal experiments. 相似文献
7.
STEPHEN C. BARR DWIGHT D. BOWMAN LYNDSEY G. PHILLIPS MARGARET C. BARR 《The Journal of eukaryotic microbiology》1993,40(3):233-237
ABSTRACT. The morphology of Trypanosoma manulis n. sp. is described from living and stained specimens obtained from the blood of a Pallas cat, Felis manul , from Kazakhstan. the cat was also infected with a Hepatozoon sp. and feline immunodeficiency virus. the morphology of the trypanosome most closely resembles that of Trypanosoma mpapuense Reichenow and Trypanosoma heybergi Rodhain found in bats. Trypanosoma manulis does not grow well in conventional media, but co-culture with African green monkey kidney cells in Eagle's Minimum Essential Medium supplemented with 10% fetal calf serum at approximately 27° C resulted in luxuriant growth of trypanosomes. Under these growth conditions, epimastigotes adhered to the surface of the culture flask and to African green monkey kidney cells, as well as forming large rosettes. At 37° C, although growth was poor, transformation of the epimastigotes into the bloodstream forms occurred. This represents the first report of a trypanosome of the subgenus Megatrypanum in a felid. 相似文献
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9.
A sample consisting of 2,252 persons among 20,199 Los Angeles civil service employees was observed for the occurrence of heart disease. The first examination measured the prevalence. Based upon the diagnosis of 165 cases of heart disease, the prevalence was 73 per 1,000 persons examined. Two reexaminations, at intervals of 12 to 18 months, of persons with normal heart on the first examination were carried out and 52 additional cases were diagnosed. There were also 13 deaths of heart disease in persons first diagnosed as having normal heart, making a total of 65 "new" cases (36.6 per 1,000) during the 30-month period of observation. An annual estimated heart disease incidence of 15 per 1,000 appears reasonable. Based on 89 deaths, the cardiovascular disease death rate was 11 per 1,000 among persons entering the study with normal heart, and 133 per 1,000 persons diagnosed as having heart disease at entry. The ratio of newly diagnosed cases to deaths of heart disease was 4 to 1.Among men diagnosed as having normal heart there was little difference in death rates whether their jobs were physically strenuous or sedentary. Among the men with heart disease, however, the highest death rates are observed among those employed at sedentary jobs and at light exertion. This may, of course, be an indication of the employee's selection of the job rather than the effect of inactivity. The relative usefulness of minifilm x-ray, electrocardiograms and questioning as to history were considered. 相似文献
10.
G. R. CAYLEY P. ETHERIDGE D. C. GRIFFITHS F. T. PHILLIPS B. J. PYE G. C. SCOTT 《The Annals of applied biology》1984,105(2):379-386
The collaborative trials described by Arnold et al., 1984a, b, c provided an extensive range of data on the performance of electrostatically charged rotary atomizers on a variety of crops, at different growth stages, using systemic and non-systemic pesticides. The purpose of this paper is to review the subject to date. 相似文献