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101.
102.
Sanjay Kapil Teresa Yeary Bill Johnson 《Veterinary Clinics of North America: Small Animal Practice》2008,38(4):755-74, vii
In this article, the authors are specifically concerned with the timely and accurate detection of emerging diseases of small animals that are viral in origin. Veterinarians are bound to encounter emerging viruses in their practice. The problem is unavoidable, because viruses are highly mutagenic. Even the immune response dictates the nature of virus that evolves in a host. If the clinical signs and diagnostic methods fail to correlate, the veterinarian should work with the diagnostic laboratory to solve the diagnostic puzzle. 相似文献
103.
Steven Walker Michael Widderick Andrew McLean Tony Cook Bill Davidson 《Weed Biology and Management》2013,13(4):144-150
Conyza bonariensis is a major weed infesting zero‐tilled cropping systems in subtropical Australia, particularly in wheat and winter fallows. Uncontrolled C. bonariensis survives to become a problem weed in the following crops or fallows. As no herbicide has been registered for C. bonariensis in wheat, the effectiveness of 11 herbicides, currently registered for other broad‐leaved weeds in wheat, was evaluated in two pot and two field experiments. As previous research showed that the age of C. bonariensis, and to a lesser extent, the soil moisture at spraying affected herbicide efficacy, these factors also were investigated. The efficacy of the majority of herbicide treatments was reduced when large rosettes (5–15 cm diameter) were treated, compared with small rosettes (<5 cm diameter). However, for the majority of herbicide treatments, the soil moisture did not affect the herbicide efficacy in the pot experiments. In the field, a delay in herbicide treatment of 2 weeks reduced the herbicide efficacy consistently across herbicide treatments, which was related to weed age but not to soil moisture differences. Across all the experiments, four herbicides controlled C. bonariensis in wheat consistently (83–100%): 2,4‐D; aminopyralid + fluroxypyr; picloram + MCPA + metsulfuron; and picloram + high rates of 2,4‐D. Thus, this problem weed can be effectively and consistently controlled in wheat, particularly when small rosettes are treated, and therefore C. bonariensis will have a less adverse impact on the following fallow or crop. 相似文献
104.
Multiple diagnostic tests to identify cattle with Bovine viral diarrhea virus and duration of positive test results in persistently infected cattle
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Robert W. Fulton Bill E. Hessman Julia F. Ridpath Bill J. Johnson Lurinda J. Burge Sanjay Kapil Barbara Braziel Kira Kautz Amy Reck 《Canadian journal of veterinary research》2009,73(2):117-124
Several tests for Bovine viral diarrhea virus (BVDV) were applied to samples collected monthly from December 20, 2005, through November 27, 2006 (day 0 to day 342) from 12 persistently infected (PI) cattle with BVDV subtypes found in US cattle: BVDV-1a, BVDV-1b, and BVDV-2a. The samples included clotted blood for serum, nasal swabs, and fresh and formalin-fixed ear notches. The tests were as follows: titration of infectious virus in serum and nasal swabs; antigen-capture (AC) enzyme-linked immunosorbent assay (ELISA), or ACE, on serum, nasal swabs, and fresh ear notches; gel-based polymerase chain reaction (PCR) testing of serum, nasal swabs, and fresh ear notches; immunohistochemical (IHC) testing of formalin-fixed ear notches; and serologic testing for BVDV antibodies in serum. Of the 12 animals starting the study, 3 died with mucosal disease. The ACE and IHC tests on ear notches had positive results throughout the study, as did the ACE and PCR tests on serum. There was detectable virus in nasal swabs from all the cattle throughout the study except for a few samples that were toxic to cell cultures. The serum had a virus titer ≥ log10 1.60 in all samples from all the cattle except for 3 collections from 1 animal. Although there were several equivocal results, the PCR test most often had positive results. The BVDV antibodies were due to vaccination or exposure to heterologous strains and did not appear to interfere with any BVDV test. These findings illustrate that PI cattle may be identified by several tests, but differentiation of PI cattle from cattle with acute BVDV infection requires additional testing, especially of blood samples and nasal swabs positive on initial testing. Also, calves PI with BVDV are continual shedders of infectious virus, as shown by the infectivity of nasal swabs over the 11-mo study. 相似文献
105.
106.
Inheritance of long grain rice amylograph viscosity characteristics 总被引:19,自引:0,他引:19
Southern United States long grain rice (Oryza sativa L.) is a unique market type characterized by intermediate amylose content,
gelatinization temperature, and amylograph viscosity profile characteristics. Rice breeders sometimes use long grain germplasm
with differing amylograph viscosity profiles. The inheritance of rice amylograph viscosity profiles has not been ascertained
and, thus, was the objective of this study. A six parent diallel (parents plus F1 hybrids) was evaluated at Stuttgart, AR during 1994 and 1995. In 1994, 65 F2 plants from the ‘L-202’ × ‘Newrex’ and L-202 × ‘Katy’ crosses were space planted, and in 1995, the 65 F2:3 lines were planted as hill plots. The inheritance of amylograph viscosity profiles appeared to be controlled by a single
locus with genes with additive effects. The results of the diallel analysis also support control by a single locus with genes
with additive effects because GCA effects were significant and SCA effects nonsignificant for peak, hot paste, and cool paste
viscosities. Intermediate amylose content and intermediate amylograph viscosity profiles were strongly correlated. Selection
first for intermediate amylose content followed by reselection for intermediate hot paste viscosities would identify long
grain genotypes with southern United States long grain cooking quality in progeny from crosses between southern United States
long grain rice genotypes and softer cooking long grain genotypes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
107.
John Gunn Rod Sein Bill Keller Peter Beckett 《Water, air, and soil pollution》2001,130(1-4):1439-1444
A 38 ha near-barren experimental catchment area near an abandoned Cu and Ni smelter in Sudbury, Canada was treated with 410 tons of coarse dolomitic limestone in 1994. An additional 54 tons of pelletized fine dolomite were added to 15 wetlands within the experimental catchment in 1995. The treatments significantly increased the pH and base cation concentrations in the outlet stream. Cu and Ni concentrations initially rose after the wetland treatment, but then declined to levels below those of the reference site. Bioassay tests revealed that the toxicity of the drainage water was greatly reduced by the liming, but some localized inputs of highly toxic groundwater still posed a problem for aquatic biota. The pH of surface water in the wetlands has been maintained at >6.0 for over 4 years. The wetland liming appeared to be highly effective at neutralizing drainage water, however there may be some adverse effects on wetland plant communities as a consequence. 相似文献
108.
M. M. Coûteaux R. Henkinet P. Pitta P. Bottner G. Billès L. Palka G. Vannier 《Biology and Fertility of Soils》1989,8(2):172-177
Summary Two experiments were carried out on a dysmoder humus sampled from a depth of 2–5 cm from a mixed hardwood forest. In acid soil, the chloroform fumigation-incubation method failed to estimate the microbial biomass, not because bacterial growth was inhibited after fumigation but because a labile C source was taken up which differed from the killed biomass C. 相似文献
109.
Duplex Doppler Estimation of Pourcelot Resistive Index in Arcuate Arteries of Sedated Normal Cats 总被引:1,自引:0,他引:1
Bill J. Rivers Patricia A. Walter Timothy D. O'Brien David J. Polzin 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(1):28-33
Renal failure is an important cause of morbidity and mortality in feline patients. In human patients, intrarenal blood flow values obtained with duplex Doppler ultrasonography have been used to aid in the diagnosis and prognosis of renal failure. The purpose of this report is to present values for resistance to intrarenal blood flow in normal cats, derived by duplex Doppler ultrasonography. Ten mature clinically healthy conditioned domestic shorthaired cats were screened for normal renal anatomy and function by CBC, serum biochemical profile, urinalysis, urine protein/creatinine ratio, endogenous creatinine clearance, and renal B-mode ultrasonography; and for normal systemic blood pressure with Doppler pressure cuff measurement. Subsequently, the cats were sedated with ketamine hydrochloride, and values for mean intrarenal (arcuate artery) resistance to blood flow were determined by duplex Doppler ultrasonography, and expressed as the Pourcelot resistive index, a ratio of systolic to diastolic flow commonly used in duplex Doppler sonography in human patients. After duplex Doppler sonographic examination, histological normalcy of the kidneys was verified by evaluation of ultrasound-guided percutaneous renal biopsy. Based on the obtained resistive indices, 95% confidence intervals for normal values were calculated as follows: left kidney, 0.52 to 0.60; right kidney, 0.55 to 0.63. No statistically significant difference was noted between the values obtained for the right versus the left kidney. J Vet Intern Med 1996;10:28–33. Copyright © 1996 by the American College of Veterinary Internal Medicine . 相似文献
110.
James H. Elford BVetMed MRCVS Bill Oxley MA VetMB DSAS MRCVS Sebastien Behr DVM DECVN MRCVS 《Veterinary surgery : VS》2020,49(2):347-353