Colibacillosis in neonatal lambs: onset of diarrheal disease and isolation and characterization of enterotoxigenic Escherichia coli from enteric and septicemic forms of the disease.     

M M Ansari  H W Renshaw  N L Gates 《American journal of veterinary research》1978,39(1):11-14

A lamb ligated intestinal segment (LIS) test was adapted to determine the enterotoxigenicity of Escherichia coli isolates obtained from fecal and blood specimens from neonatal lambs with overt diarrheal disease. The lamb LIS was distended by 28 of 80 (37%) isolates from fecal specimens from 23 affected lambs. Enterotoxigenic E coli isolations were made from 10 of the 23 lambs examined. Isolates of E coli were made from the blood of 17 of 76 (22%) animals with severe diarrheal disease. Distention of the lamb LIS was caused by 3 of 39 (7.7%) isolates from 2 of 17 lambs with E coli septicemia. All lambs (n = 266) that were born during a 4-day period in an intensified shed lambing operation and that were not given prophylactic antibiotic therapy developed diarrheal disease within 28 hours of birth. Signs of enteric disease appeared in lambs born during inclement weather in a significantly (P less than 0.001) shorter period than in those born during mild weather conditions.  相似文献   

The brucellosis and tuberculosis status of wood bison in the Mackenzie Bison Sanctuary, Northwest Territories, Canada.   总被引：1，自引：0，他引：1       下载免费PDF全文

S V Tessaro  C C Gates    L B Forbes 《Canadian journal of veterinary research》1993,57(4):231-235

Postmortem examinations were done on 51 wood bison (Bison bison athabascae) killed as part of a multidisciplinary research project in the Mackenzie Bison Sanctuary, Northwest Territories, Canada, between 1986 and 1988. There was no gross, histological or bacteriological evidence of brucellosis or tuberculosis in these bison. Traumatic lesions were seen in one calf that had been attacked by wolves and a second calf that had been gored. Antibody titers to Brucella abortus were not found in sera from these 51 animals or an additional 112 wood bison that were chemically-immobilized or killed in the Sanctuary between 1986 and 1990. The combined prevalence of the diseases in the population could not have exceeded 5.95% for the necropsy survey to have missed finding at least one infected animal, and the prevalence of brucellosis in the population would have had to be less than 1.95% for the broader serological survey to have failed to find at least one reactor animal on the battery of tests. These results, and the cumulative epidemiological information on brucellosis and tuberculosis in bison, indicate that bovine brucellosis and tuberculosis are not enzootic in the wood bison population in and around the Mackenzie Bison Sanctuary, and suggest that the population is free of these diseases. However, this expanding population is at risk of contracting both diseases from the infected bison population in and around nearby Wood Buffalo National Park.  相似文献   

Neutralizing antibody in experimentally induced respiratory infection in calves   总被引：2，自引：0，他引：2  

G A Gates  T C Cesario  J W Ebert  R L Kriel  H T Wulff  J D Poland  D E Gutekunst  T D Chin 《American journal of veterinary research》1970,31(2):217-224

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Chronic toxicosis of sheep from the organic herbicide di-allate     

J S Palmer  M Haufler  L M Hunt  J C Schlinke  C E Gates 《American journal of veterinary research》1972,33(3):543-546

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Listeric myelitis in sheep     

G A Gates  D C Blenden  L D Kintner 《Journal of the American Veterinary Medical Association》1967,150(2):200-204

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Not all cows are epidemiologically equal: quantifying the risks of bovine viral diarrhoea virus (BVDV) transmission through cattle movements     

M Carolyn Gates  Roger W Humphry  George J Gunn  Mark E J Woolhouse 《Veterinary research》2014,45(1)

Many economically important cattle diseases spread between herds through livestock movements. Traditionally, most transmission models have assumed that all purchased cattle carry the same risk of generating outbreaks in the destination herd. Using data on bovine viral diarrhoea virus (BVDV) in Scotland as a case example, this study provides empirical and theoretical evidence that the risk of disease transmission varies substantially based on the animal and herd demographic characteristics at the time of purchase. Multivariable logistic regression analysis revealed that purchasing pregnant heifers and open cows sold with a calf at foot were associated with an increased risk of beef herds being seropositive for BVDV. Based on the results from a dynamic within-herd simulation model, these findings may be partly explained by the age-related probability of animals being persistently infected with BVDV as well as the herd demographic structure at the time of animal introductions. There was also evidence that an epidemiologically important network statistic, “betweenness centrality” (a measure frequently associated with the potential for herds to acquire and transmit disease), was significantly higher for herds that supplied these particular types of replacement beef cattle. The trends for dairy herds were not as clear, although there was some evidence that open heifers and open lactating cows were associated with an increased risk of BVDV. Overall, these findings have important implications for developing simulation models that more accurately reflect the industry-level transmission dynamics of infectious cattle diseases.  相似文献   

Type II Supernova Matter in a Silicon Carbide Grain from the Murchison Meteorite     

P Hoppe  R Strebel  P Eberhardt  S Amari  RS Lewis 《Science (New York, N.Y.)》1996,272(5266):1314-1316

The circumstellar silicon carbide (SiC) grain X57 from the Murchison meteorite contains large amounts of radiogenic calcium-44 (20 times its solar system abundance) and has an anomalous silicon isotopic composition, different from other circumstellar SiC grains. Its inferred initial 44Ti/Si and 44Ti/48Ti ratios are 1.6 x 10(-4) and 0.37. In addition, it contains radiogenic magnesium-26; the inferred initial 26Al/27Al ratio is 0.11. The isotopic and elemental data of X57 can be explained by selective mixing of matter from different zones of a typical type II supernova of 25 solar masses during its explosion. The high 44Ti/Si ratio requires contributions from the innermost nickel zone of the supernova to the SiC condensation site, as similarly suggested by astronomical observations.  相似文献   

Clay Mineral Composition of Borate Deposits and Associated Strata at Boron,California     

Gates GR 《Science (New York, N.Y.)》1959,130(3367):102

X-ray analyses of samples from lacustrine deposits in the Kramer borate district of California show that montmorillonite is the dominant clay mineral, and that illite is abundant in red siltstones, common in green and gray borate-barren claystones, and sparse in borate-bearing rocks. Kaolinite is present only in red siltstones. The distribution of clay minerals is related to the geologic history of borate deposition.  相似文献   

THE GARGOYLE AS A SCIENTIFIC INSTRUMENT     

Gates FC 《Science (New York, N.Y.)》1929,70(1806):148-149

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IDENTICAL TWINS IN A MOUSE CROSS     

Castle WE  Gates WH  Reed SC  Snell GD 《Science (New York, N.Y.)》1936,84(2191):581-582

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