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Heather E Clarke Helen Kado-Fong David J Maggs 《Journal of veterinary diagnostic investigation》2006,18(4):388-391
The purpose of this study was to report methods currently recommended by commercial laboratories for collecting, shipping, and processing of samples for feline herpesvirus type 1 (FHV-1) testing using polymerase chain reaction (PCR) and to determine the effect of temperature and time on the ability of 1 PCR method to detect FHV-1 DNA in experimental and clinical samples. Eleven laboratories offering FHV-1 PCR were surveyed. There was notable variation in sample types and shipping conditions recommended and PCR protocols used by these laboratories. Subsequently, using a single PCR method, FHV-1 DNA was detected in samples exposed to various temperatures within the laboratory. Finally, FHV-1 PCR was performed on paired clinical samples collected from 25 cats and shipped at ambient temperatures via US Postal Service (USPS) or with an ice pack via a courier. Samples sent by USPS were exposed to significantly longer transit time and arrived at significantly higher temperature than did samples sent by courier. Despite this, all sample pairs yielded concordant results when tested for FHV-1 DNA using this PCR method. Although it may not be necessary for samples collected for detection of FHV-1 DNA using this PCR method to be shipped under the most expedient or temperature-controlled conditions, this should be verified for a variety of PCR assays and sample types. 相似文献
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Wendy Pearson Semir Omar Andrew F. Clarke 《Canadian journal of veterinary research》2007,71(3):213-217
The purpose of this study was to determine if ginseng fed at low levels enhances a horse's antibody response to vaccination against Equid herpesvirus 1 (EHV-1). For 28 d, 5 horses received ground, powdered ginseng (35 mg/kg body weight, 1.7 mg/kg total ginsenosides) in molasses as a carrier, and 5 received molasses only. On day 14, each horse was vaccinated against EHV-1. The time course of the antibody response to vaccination was significantly altered in the horses receiving ginseng, a clinically relevant increase in antibody titer being observed by postvaccination day 2 compared with day 6 in the control horses. The horses receiving ginseng also had a significant decrease in serum levels of sodium and a significant increase in serum levels of potassium. No adverse effects of ginseng treatment were identified by hematologic and blood biochemistry profiles. Thus, low-dose dietary supplementation with ginseng in healthy horses may be a useful adjunct to vaccination. 相似文献
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Dunlop RH McEwen SA Meek AH Friendship RA Clarke RC Black WD 《The Canadian veterinary journal. La revue veterinaire canadienne》1998,39(2):87-96
A mail survey of swine producers in Ontario was undertaken during 1991 to describe the types, frequency, and motives for antimicrobial use. Two hundred operations that marketed fewer than 350 hogs per year, and 800 that marketed more than 350 per year were sent questionnaires, 63% of which were completed and returned. Most operations (86%) added antimicrobials to starter (weanling pig) rations, while fewer (29%) added these drugs to finisher pig rations. The most commonly used antimicrobials were tylosin, carbadox, and furazolidone in weanling pigs, and tylosin, lincomycin, and tetracycline in finishers. Water medication of grower-finisher pigs was practised on 25% of farms; 80% of farms had injected at least some grower-finisher pigs with antimicrobials in the 12 mo preceding the survey. Approximately 20% of operations that added antimicrobials to finisher rations did so for growth promotion purposes only, while others used them for disease treatment, prevention, control, or a combination of reasons. Among those not using antimicrobials in finisher rations, 83% did not believe they were necessary and 37% were concerned about the potential for residues in marketed hogs. 相似文献
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R.H Dunlop S.A McEwen A.H Meek R.C Clarke W.D Black R.M Friendship 《Preventive veterinary medicine》1998,34(4):1610-305
Logistic regression was used to model associations between antimicrobial treatment and resistance among fecal Escherichia coli of finisher pigs at the farm level. Four sets of potential risk factors representing different levels of refinement of antimicrobial use on farms were modelled on resistance to antimicrobials. Final models for each antimicrobial were constructed from treatment and management variables significant on initial screening, and corrections for overdispersion were made. In general, in-feed antimicrobial treatment of pigs was more consistently associated with an increased risk of resistance than individual-animal treatment. Antimicrobial treatment in starter rations was significant in final models of resistance to ampicillin, carbadox, nitrofurantoin, sulfisoxizole, and tetracycline. Treatment in grower–finisher rations was significantly associated with resistance to ampicillin, spectinomycin, sulfisoxizole, and tetracycline. There was little evidence that in-feed antimicrobials increased the risk of resistance to gentamicin, which is a drug used only for individual-pig treatment in this study population. These results suggest that antimicrobial medication of rations of post-weaning pigs selects for and maintains antimicrobial resistance among E. coli of finisher pigs. Although resistance was common on farms that did not medicate rations of post-weaning pigs, the results indicate that antimicrobial use does increase the risk of resistance to the antimicrobials studied. 相似文献
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Traditional agroforestry systems in the communal areas of Zimbabwe are described. There are systems centered on main fields, on home gardens, on homesites and on grazing areas. In the main fields, the major tree-related management practice is the conservation of preferred indigenous fruit trees. Fruit trees are also the focus of forestry activities around the gardens and the homesite; but here it is the planting of exotic species. In a localized area of Zimbabwe Acacia albida is important in fields. There is almost no use of tree fallows in Zimbabwe. Trees in grazing areas have numerous roles, but at present there is little knowledge about traditional management practices in these areas. In the development of agroforestry systems in Zimbabwe it is suggested that those systems designed to improve fodder production will make a significant contribution to farm productivity because of the importance of cattle in the farming system and the present fodder shortage. Interventions involving the planting of fruit trees are likely to be very successful, as there is much interest in such planting. Another area that needs to be developed is that of tree plantings to improve soil fertility. 相似文献
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