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61.
Objective  To investigate the effect of pre-anaesthetic fasting time and variety of food on gastric content (GC) volume and pH in dogs.
Study design  Randomized, cross-over, prospective experimental study.
Animals  Fifteen mongrel dogs (nine females and six males 1–4 years old, weighing 10–24.5 kg).
Methods  Each dog received the same seven treatments in random order: dry food 3 hours before anaesthesia (BA) (treatment 3D), canned food (half daily rate) 3 hours BA (treatment 3C), 0% fat cow milk 3 hours BA (treatment 3M), dry food 10 hours BA (treatment 10D), canned food 10 hours BA (treatment 10C), low fat canned food 10 hours BA (treatment 10F) and low protein canned food 10 hours BA (treatment 10P). All animals were pre-medicated with propionyl promazine and anaesthesia was induced with thiopental sodium and maintained with halothane. GC was aspirated using an orogastric catheter and its volume and pH were measured.
Results  Treatment 10F had significantly lower GC pH than all the 3-hour treatments. Treatments 10D and 10P had significantly lower pH than treatments 3D and 3C. Treatment 3M had significantly lower pH than the other 3-hour treatments. Treatment 3D had significantly greater gastric volume than treatments 3M, 10C, 10F and 10P.
Conclusions and clinical relevance  Canned food at half the daily rate administered 3 hours before anaesthesia did not increase significantly the GC volume compared to the other types of food used. The GC pH was also high. This type of food fed 3 hours before induction of anaesthesia may be of benefit in reduction of the incidence of gastro-oesophageal reflux during anaesthesia in dogs.  相似文献   
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The effect of five levels of nitrogen fertilization on the growth and nutritional quality of Cos lettuce (Lactuca sativa L. cv. Parris Island) at harvest and after storage was studied during autumn and winter in South-West Greece. Plants were cultivated hydroponically in a greenhouse and the nitrate, chlorophyll and ascorbic acid (vitamin C) concentrations within the plant tissues were measured at harvest and following storage at 5 or 10 °C for 10 days. Nitrate accumulated in the leaves with increasing amounts of N within the nutrient solution and was higher in the winter than in the autumn. At the lowest N level (20 mg L−1), the inner leaves accumulated more nitrate than the outer leaves, whereas at higher N levels (140, 200 or 260 mg L−1) nitrate accumulation was higher in the outer leaves. Overall, the highest nitrate concentrations were detected in the petiole and the proximal end of the leaf, but at the lowest N application rate (20 mg L−1) nitrate accumulated in the distal region of the leaf too. Although the nitrate concentrations within the leaves did not change significantly during 10 days storage at 5 or 10 °C, the chlorophyll and vitamin C concentrations decreased. Chlorophyll loss was higher in lettuce that was grown under low N levels and was higher at 10 °C than at 5 °C, but was reduced by enclosure of the lettuce in polyethylene film. It is concluded that the optimum N application rate for Cos lettuce grown hydroponically under cover during autumn and winter in South-West Greece, and in other areas with a similar climate, is 200 mg N L−1 because at this N rate yield is satisfactory and leaf nitrate concentrations are below the maximum acceptable level for human consumption. Nutritional value (vitamin C concentration) and market quality (chlorophyll content) are highest at harvest and decrease during storage, but quality in terms of nitrate concentration does not change.  相似文献   
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ABSTRACT

Strawberry is susceptible to several systemic pathogens and, in particular, viruses. There are several examples of disease epidemics that resulted from virus-infected propagation material and led to losses estimated in the tens of millions of dollars. This communication focuses on actions needed to minimize the risk of similar outbreaks by developing a systems-based approach from breeding to the commercial field. This includes the development of molecular biology and bioinformatic tools that allow for the detection of all known viruses infecting strawberry but most importantly for the discovery of viruses that circulate in the system undetected and may have contributed to past epidemics. Surveys in commercial fields have yielded a map of the most prevalent viruses in strawberry production areas across the United States, knowledge that will be used in the nascent National Certification Program for Strawberry.  相似文献   
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你喂给你的断奶猪吃的颗粒料是不是很硬或者是碎的?颗粒比较硬的优点是,从饲料厂经过长途运输直到达到饲槽中为止一直都能够保持其物理形态上的完整。然而,我们有充分的理由相信、很硬的颗粒料不是幼猪所喜欢的。  相似文献   
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The objective of the study was to investigate the efficiency of three enrichment methods to separate boar spermatozoa. Twenty-four ejaculates from 12 boars (2 ejaculates/boar) were extended (30 × 106 spermatozoa/mL) in commercial Beltsville Thawing Solution. Each semen sample was processed with glass wool column (GW) and glass beads (GB) filtration and with the single-layer centrifugation (SLC) technique. Semen samples before (control; C) and after treatment were evaluated for sperm CASA motility/kinetics and concentration, viability, morphology and chromatin integrity. Data were analysed with mixed models. The concentration of total and motile spermatozoa was significantly decreased after treatment in groups GW and SLC, but not in group GB. Group GW showed increased values of WOB compared with both groups C and GB. Group GB showed greater values of rapid movement spermatozoa and lower values of slow movement spermatozoa compared with group C. In group SLC, higher values of VSL, LIN and STR were observed compared with group C. In conclusion, all techniques under examination enhanced various CASA variables. Based on our results, the GB method is a promising alternative separation technique for boar sperm and deserves further research regarding swine in vitro fertilization.  相似文献   
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