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81.
M. L. Vitosh J. W. Noling G. W. Bird R. W. Chase 《American Journal of Potato Research》1980,57(3):101-111
The joint action of nitrogen fertilizer and nematicides onPratylenchus penetrons and yield was investigated using three potato varieties (Superior, Onaway and Russet Burbank), three rates of nitrogen (84, 168 and 336 kg/ha), five edaphic pesticides (disulfoton, aldicarb, 1,3-D + MIC, carbofuran and thiofanox), and an insecticide spray to minimize the role of foliar feeding insects In 1977, disulfoton, aldicarb, and disulfoton plus 1,3-D + MIC significantly increased the yield of Superior at all nitrogen rates. The yield increases ranged from 37–56% for Superior, 15–35% for Onaway and 13–27% for Russet Burbank. Nitrogen had no detectable influence on yield. Population densities ofP. penetrans were significantly reduced by disulfoton plus 1,3-D + MIC and by aldicarb. Superior was most susceptible toP. penetrans, Onaway intermediate, and Russet Burbank moderately tolerant. Neither the potato variety or nitrogen significantly influenced the population densities ofP. penetrans In 1978 aldicarb, 1,3-D + MIC and thiofanox significantly increased yields of Superior at all nitrogen rates. Nitrogen also significantly increased yields, but only where aldicarb and 1,3-D + MIC were applied. Total yield was increased 12–14% and 17–23% by 1,3-D + MIC and aldicarb at 168 and 336 kg N/ha, respectively. Aldicarb, 1,3-D + MIC, and thiofanox appeared to increase tuber set, while nitrogen increased tuber size. Although all of the nematicides provided some control ofP. penetrans, aldicarb had the highest degree of efficacy and gave excellent season-long control 相似文献
82.
W. R. Whalley C. W. Watts M. A. Hilhorst N. R. A. Bird J. Balendonck & D. J. Longstaff 《European Journal of Soil Science》2001,52(3):511-519
In recent years the use of porous material sensors for matric potential, which were originally intended for soil drier than ?100 kPa, has been extended to wet soils. In these wetter soils, unpredictable behaviour of the sensors has been reported. We have studied the design of porous material sensors of matric potential in soil and propose a hypothesis to explain this unpredictability, and suggest recommendations for a design of sensor which will behave more reliably. The development of an experimental porous material sensor of matric potential based on this design is described. It operates between 0 and ?60 kPa, and both the drying and wetting moisture characteristics were measured. In this sensor the porous material was a ceramic and its water content was measured with a dielectric water content sensor. We tested a simple closed‐form hysteresis model to convert the measured water content of the porous material into matric potential under laboratory conditions. This was shown to give better results than using a calibration based on the drying moisture characteristic curve, where the predicted matric potentials were too small. The use of the experimental sensors in the field environment is described. Both types of sensor were installed using the same procedure. As far as we are aware the experimental sensor described in this paper is the first porous material sensor of matric potential that can be installed in the same way as a conventional tensiometer. Both conventional tensiometers and the experimental porous material sensors gave similar estimates of matric potential. 相似文献
83.
Acoustical technologies have been used to evaluate characteristics of ecosystems, including soil, demographics and organism behavior. In our research, the acoustics of four states of yard and kitchen refuse compost were analyzed. These included: compost with and without water, and microwaved compost with and without water. The acoustics generated by the microwaved and non-microwaved composts were recorded in a sound chamber. Water was then added to the control and microwaved samples. Subsequently, the acoustics were recorded again. Sonograms were produced for each of the four treatments and the data analyzed in relation to sound Power Spectral Density (PSD). With the addition of water, the nonmicrowaved compost became acoustically active. The PSD was more than five times greater (p < 0.0001, ANOVA repeated measures) than the microwaved compost with and without water and the non-microwaved compost without water. Most of the PSD for all four treatments was in the lower kHz frequency levels (1-4). KHz frequency level one contained the majority of the sound. Compost plus water, had significantly more PSD at kHz level 1 than the sum of kHz levels 2-11. Most of the remaining PSD was found in the lower kHz frequencies. It is concluded that: 1) compost can be considered as a place where organisms are often dormant, and 2) compost can be activated with water used as a pulsing agent. 相似文献
84.
Yuki M Sugimoto N Takahashi K Ohtsuka H Nishii N Suzuki K 《Journal of Feline Medicine and Surgery》2006,8(5):349-352
An 8-year-old female Persian cat was brought in for evaluation of chronic vomiting. The presence of opaque enteric foreign bodies and intestinal obstruction along with azotaemia, hyperphosphataemia, moderate anaemia and peritoneal fluid were revealed following appropriate diagnostic work-up. Exploratory laparotomy confirmed jejunoileal dilation, ileocaecal stenosis, and numerous foreign objects in the jejunoileum. These foreign objects and ileocaecal stenosis were surgically removed, and intestinal resection and anastomosis was performed. The patient recovered favourably. Analysis revealed that the foreign objects were composed of calcium phosphate and calcium carbonate. Intestinal inflammation and stenosis secondary to enterolithiasis may have developed following ingestion of cat litter or a previous unrelated surgical intervention. We were unable to delineate the inciting pathogenesis in this particular case. 相似文献
85.
Rift Valley fever(RVF) virus is an arbovirus in the Bunyaviridae family that, from phylogenetic analysis, appears to have first emerged in the mid-19th century and was only identified at the beginning of the 1930's in the Rift Valley region of Kenya. Despite being an arbovirus with a relatively simple but temporally and geographically stable genome, this zoonotic virus has already demonstrated a real capacity for emerging in new territories, as exemplified by the outbreaks in Egypt (1977), Western Africa (1988) and the Arabian Peninsula (2000), or for re-emerging after long periods of silence as observed very recently in Kenya and South Africa. The presence of competent vectors in countries previously free of RVF, the high viral titres in viraemic animals and the global changes in climate, travel and trade all contribute to make this virus a threat that must not be neglected as the consequences of RVF are dramatic, both for human and animal health. In this review, we present the latest advances in RVF virus research. In spite of this renewed interest, aspects of the epidemiology of RVF virus are still not fully understood and safe, effective vaccines are still not freely available for protecting humans and livestock against the dramatic consequences of this virus. 相似文献
86.
87.
Estimation of genetic parameters for carcass defects of Japanese Black cattle in Kagoshima
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Kazutaka Nishi Takeshi Shimogiri Akinori Kusano Shinichi Sakamoto Kiyomi Shiromoto Kotaro Kawabe Shin Okamoto Takeshi Honda Kenji Oyama 《Animal Science Journal》2016,87(5):655-660
Cattle exhibit a range of carcass defects, including blood splash (BLS), intramuscular edema (INE), muscle steatosis (MUS), bruising (BR), trim loss (TRL) and others (OTH). These defects lower the carcass value and can result in significant economic loss to producers. We estimated the incidence, relationship with inbreeding coefficients and genetic parameters of carcass defects in Japanese Black cattle using 561 619 carcass records from Kagoshima, Japan during April 1988 through March 2011. The defect incidence ranged from 0.22% for TRL to 5.73% for BR. The incidence of MUS and BR increased from 1.21% to 6.57% and from 1.06% to 9.31%, respectively. The incidence of INE peaked at 7.44% in 1999 and decreased thereafter. We observed a positive linear relationship between the defect incidence and the inbreeding coefficients in MUS, BR and TRL (P < 0.01). The heritabilities estimated by univariate animal model with Gibbs sampling for BLS, INE, MUS, BR and TRL were 0.24, 0.06, 0.18, 0.05 and 0.02, respectively. The contribution of farm variance to phenotypic variance was negligible (0.01 to 0.04). Significant genetic correlations of TRL were estimated with MUS (0.63) and BR (0.63). Our results suggest that genetic factors contribute to the incidence of BLS and MUS. 相似文献
88.
As a result of a Ministry of Agriculture & Fisheries survey on ovine abortions, 76 isolates of Campylobacterfetus fetus were obtained. These isolates were from four farms in the southern Hawkes Bay, with an abortion incidence of 2.8% to 9.1%. Antisera to eight different strains of C. fetus fetus were made in rabbits. Strains were then examined using whole cell tube agglutination tests and sensitised Staphylococcal Protein A slide agglutination tests. Heat labile antigens were examined by absorbing antisera with heat-treated bacteria. Two broad serogroups were found, but within-group variation was demonstrated by cross-absorbing antisera. The isolates from one farm were all of a single broad serogroup. Both serogroups were found on the remaining three farms. Evidence for the presence of two major serogroups was also obtained by immobilisation tests and antigen analysis by gel diffusion. 相似文献
89.
90.