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An experiment was conducted beginning in 1969 to determine the chipability of several cultivars of potato (Solarium tuberosum) grown under similar cultural regimes at different locations throughout Ohio. The experiment included 19 cultivars and 11 locations. The tubers from a particular location were harvested and transported to the laboratory where a portion was chipped and other portions were stored at 40,45,50, and 55°F for 3 and 6 months and subsequently chipped. The chips were analyzed for color both objectively using the Agtron M-30-A and subjectively using the PC/SFA color chart. In addition, specific gravity and count were also determined before storage. Not all cultivars were included for the duration of the experiment as they proved consistently superior or inferior in the early stages of the experiment or they were unavailable. Also, not all locations were included each year due to non-availability of acreage. The data indicate that there was a high degree of variability among cultivars and growers. They also indicate considerable variability among years of production although good cultivars were rated highest within seasons. Most notable was the variability among locations; the variation from one location to another was often as great as that among cultivars. Storage difference was pronounced as expected due to temperature regimes.  相似文献   
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OBJECTIVE: To evaluate viral and bacterial respiratory pathogens and Mycoplasma spp isolated from lung tissues of cattle with acute interstitial pneumonia (AIP) and cattle that had died as a result of other causes. SAMPLE POPULATION: 186 samples of lung tissues collected from cattle housed in 14 feedlots in the western United States. PROCEDURE: Lung tissues were collected during routine postmortem examination and submitted for histologic, microbiologic, and toxicologic examinations. Histologic diagnoses were categorized for AIP, bronchopneumonia (BP), control samples (no evidence of disease), and other disorders. RESULTS: Cattle affected with AIP had been in feedlots for a mean of 1272 days before death, which was longer than cattle with BP and control cattle. Detection of a viral respiratory pathogen (eg, bovine respiratory syncytial virus [BRSV], bovine viral diarrhea virus, bovine herpesvirus 1, or parainfluenza virus 3) was not associated with histologic category of lung tissues. Bovine respiratory syncytial virus was detected in 8.3% of AIP samples and 24.0% of control samples. Histologic category was associated with isolation of an aerobic bacterial agent and Mycoplasma spp. Cattle with BP were at greatest risk for isolation of an aerobic bacterial agent and Mycoplasma spp. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results suggests that AIP in feedlot cattle is not a consequence of infection with BRSV. The increased, risk of isolation of an aerobic bacterial agent from cattle with AIP, compared with control cattle, may indicate a causal role or an opportunistic infection that follows development of AIP.  相似文献   
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Sulfur-related polioencephalomalacia is frequently associated with a high total sulfur intake by ruminants. The onset of clinical signs coincides with excessive ruminal sulfide production. Measurement of ruminal gas cap hydrogen sulfide makes it possible to identify cattle with potentially hazardous total sulfur intake. Evaluation of all potential sulfur sources is necessary to estimate total dietary sulfur concentration, which can lead to prevention strategies.  相似文献   
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