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121.
The death of a 6-week-old alpaca being treated for acute polyarthritis is described. Post-mortem and histological findings included fibrinous mural endocarditis, lung abscessation, acute passive congestion of the liver, embolic suppurative nephritis and chronic nonsuppurative polyarthritis. Actinobacillus suis was isolated from the heart lesion and in pharyngeal swabs from four of six clinically normal alpacas in the same flock. 相似文献
122.
100 faeces samples of cattle were investigated in comparison to a recent commercially available Salmonella Rapid Test (OXOID) and a cultural standard method (non-selective enrichment in buffered peptone water, selective enrichment in RAPPAPORT-VASSILIADIS-medium) for presence of Salmonella. The Salmonella Rapid Test showed in positive results an accuracy ("sensitivity") of 94.7% and in negative results an assurance ("specificity") of 97.5% and is therefore suitable for rapid detection (within 2 days) of faeces sample of cattle with Salmonella. 相似文献
123.
The functions of the ovaries were controlled in 92 cattle over a period of 12 to 95 days p.p. Cystic follicles developed in 61% (25 from 41) during reconvalescence period and were correlated with a 4.2 days earlier onset of ovarian function, which was assured statistically. All together in 41 animals cystic degeneration was registered. Cysts having appeared before day 39 p.p. receded spontaneously in 24%, those having developed later remained. By application of the GnRH-analogous Buserelin (Receptal), either exclusive or combined with beta-carotene or Prostaglandin Trometamol-Tiaprost (Iliren) ovarian function could be restored in all cases. Restitution was most rapid when using Buserelin plus beta-carotene (Fertilizing insemination 3 weeks post application), but protracted after the consecutive method of therapy. All 92 cattle became pregnant. The P4-level of all "cyst-cows" were low, i.e. between 0.68 and 0.81 ng/ml of skimmed milk. The increase of conductivity of the cervical mucus to above 30 Ohm turned out an evidence of an ovarian cyst to be present. Restoration took longer in correlation with the increasing diameter of the cysts. 相似文献
124.
125.
The copper status of dairy herds in the Waikato, Taranaki and Northland regions between 1 August and 30 September was assessed by copper determinations made on composite sera from ten cows in each herd. Comparisons were made between two major groups categorised as as received and supplemented. In the latter, the cows received 2.0-6.0 g/day of copper sulphate orally from late gestation to the end of lactation. Mean copper values were determined from pastures in Taranaki and Northland and from pastures from three soil types in the Waikato. The lowest were in Northland (134.3 micromol/kg) and the highest in Taranaki (173.3 micromol/kg). Calculated dietary available copper levels showed the lowest were from pastures grown on organic soils in the Waikato. These soils also had high molybdenum levels. Serum copper values as received were lowest in Northland (7.30 micromol/l), and were marginal for both Taranaki (9.91 micromol/l) and the Waikato (9.93 micromol/l). The levels in supplemented herds were considerably higher, i.e. from the Waikato 11.7 micromol/l and from Taranaki 11.5 micromol/l. When liver and serum copper levels from paired samples were compared there was a reasonable correlation (r = 0.64) but the standard deviation approximated the mean liver copper level, i.e. 155 +/- 141 micromol/l. 相似文献
126.
Danielsen EF 《Science (New York, N.Y.)》1981,211(4484):819-821
The plume of the major eruption of Mount St. Helens on 18 May 1980 penetrated 10 to 11 kilometers into the stratosphere, attaining heights of 22 to 23 kilometers. Wind shears rapidly converted the plume from an expanding vertical cone to a thin, slightly inclined lamina. The lamina was extruded zonally in the stratosphere as the lower part moved eastward at jet stream velocities, while the upper part slowly moved westward in the region of nonsteady transition from the westerlies to the summer stratospheric easterlies. Trajectories computed to position the NASA U-2 aircraft for sampling in the plume are described. Plume volume after 8 hours of strong volcanic emission is estimated at 2 x 10(6) cubic kilometers. Only about 1 percent of this volume is attributed to the volcano; the rest was entrained from the environment. 相似文献
127.
Radiocarbon dates associated with engraved stones from sealed archeological deposits at Wonderwerk Cave in the northern Cape Province indicate that rock engraving in South Africa is at least 10,000 years old. 相似文献
128.
129.
In this investigation electrical conductivity (EC) and somatic cell concentration (SCC) were compared in 3 herds for their ability to correctly identify the infection status of quarters. For EC, thresholds of 6.0 and 6.8 mS/cm were used and comparisons were made between quarters within each cow. The method of comparison between quarters was the same as that described by the manufacturers of the AHI Mastitis Detector. For SCC a threshold of 500 x 10(3) cells/ml was used. For both EC and SCC considerable variation was found between herds for sensitivity (the proportion of quarters infected with a major pathogen and detected as abnormal), and specificity (the proportion of quarters free from infection and detected as normal). The mean sensitivity and specificity of EC for the three herds was 49% and 79% respectively, whereas for SCC the means were 71% and 81% respectively. The variation in sensitivity and specificity of EC between herds was attributed to differences in the distribution of EC for quarters of similar infection status. It was concluded that these differences in herd EC precluded the use of pre-determined EC thresholds which were applicable for detecting mastitis in all herds. 相似文献
130.
Windle WF 《Science (New York, N.Y.)》1980,209(4464):1486-1491
This is an account of the vicissitudes of the monkeys on Cayo Santiago. In it is described the relationship of the establishment of that primate colony to the development of the National Regional Primate Research Center Program in the United States and the Laboratory of Perinatal Physiology in Puerto Rico. The Cayo Santiago colony opened new aspects of biomedical research and stimulated the general use of nonhuman primates in behavioral as well as physiological investigations. 相似文献