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以0.25+6+12×0.225HT钢丝帘线替代3+9+15×0.22+0.15钢丝帘线应用于11.00R20 18PR全钢载重子午线轮胎胎体。试验结果表明,以0.25+6+12×0.225HT钢丝帘线替代3+9+15×0.22+0.15钢丝帘线用于11.00R20 18PR全钢载重子午线轮胎胎体后,成品轮胎的外缘尺寸变化不大,强度性能和耐久性能提高,且轮胎原材料成本降低。 相似文献
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The effects of lactic acid-based spray washing on bacterial profile and quality of chicken carcasses
《Food Control》2016
Chicken products with high water and nutrient contents provide essential nutrients for microbial growth. This study was designed to determine the effect of lactic acid-based spray washing. First, the reduction of microbial counts on chicken carcasses was evaluated through lactic acid-based spray washing. Second, bacterial diversity on chicken carcasses in different steps in a chicken-slaughtering chain was investigated through polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The effect of spray washing on quick-frozen chicken quality was also examined. Results revealed that microbial counts decreased significantly after the chickens were spray-washed with 1.5% lactic acid at 50 °C for 15s. PCR-DGGE revealed a decrease in microbial counts of several bacterial species, such as uncultured bacterium, uncultured Clostridiales sp., Pseudomonas fluorescens, Ruminococcus sp., and uncultured Ruminococcus sp. The spray washing performed did not remarkably affect the pH and total volatile basic nitrogen of quick-frozen chicken during storage. Therefore, the proposed technique may be applied to chicken-slaughtering chains and may be used to investigate bacterial diversity on chicken carcasses. 相似文献
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Records of cattle slaughtered at two Chilean slaughterhouses (SLH1 and SLH2) were used to determine prevalence and risk factors for carcasses with bruises. Bruise prevalence amounted to 12.3% but differed between slaughterhouses (20.8% for SLH1 and 8.6% for SLH2 respectively). Bruise severity grade 1 (mild) was most frequently recorded. The type of the animal, source of animal, the level of fat cover and lairage time were associated with the presence of bruises. Older categories of animals and animals that pass through a market before being moved to the slaughterhouse are more prone to show bruises. The results also indicate that under the reported Chilean circumstances animals that have longer lairage times (over 12 h) have a significantly reduced risk for bruises, except for oxen. Presence of bruises is also significantly associated with increased carcass pH values. 相似文献
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Rogers CA Fitzgerald AC Carr MA Covey BR Thomas JD Looper ML 《Journal of dairy science》2004,87(5):1558-1564
A 3-phase study was conducted to assess on-farm management decisions to reduce antibiotic residue violations and improve carcass characteristics in market (cull) dairy cows. In Phase 1, questionnaires were mailed to dairy producers (n = 142) to determine current on-farm management strategies for reducing antibiotic residues in market dairy cattle. In Phase 2, Holstein market cows (n = 77) were assigned randomly to each of the 3 feeding treatments (0, 30, or 60 d). Average daily gain (ADG), body condition score (BCS), and carcass characteristics were assessed. Phase 3 determined the meat withdrawal time of Holstein cows (n = 62) administered procaine penicillin G. Eighty-six percent of dairy farms responding to the questionnaire had at least one cow condemned annually, and no producer had a designated feeding protocol for market cows prior to selling. In Phase 2, ADG was greater in cows fed for 30 d (1.4+/-0.6 kg/d) than in cows fed for 60 d (0.9+/-0.4 kg/d). Additional feeding did not influence the carcass characteristics studied with the exception of kidney, pelvic and heart fat, which was higher in cows fed for 60 d compared with those fed for 0 and 30 d. In Phase 3, 31% of cows treated with procaine penicillin G exceeded the 10-d label withdrawal recommendation by an average of 3.1+/-1.9 d. Feeding market cows may not influence carcass characteristics, but can increase ADG and may ensure that recommended meat withdrawal times for antibiotics are exceeded. 相似文献
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BACKGROUND: Plant breeders have attempted to improve the nutritonal value of lucerne (alfalfa) by selecting for higher protein and lower fibre concentrations. Although targeted at ruminants, such changes could also improve the nutritional value of lucerne for monogastrics. The objective of this study was to determine the effects of graded levels of dehydrated lucerne meal on nutrient digestibility, performance and carcass traits of swine. RESULTS: The digestibility of dry matter, protein and energy declined linearly (P < 0.05) as the level of lucerne meal in the diet increased. Including lucerne meal at levels greater than 75 g kg?1 was detrimental to the growth rate of pigs during the growing period. During the finishing period, inclusion of lucerne meal at 75 and 150 g kg?1 resulted in improvements in weight gain and feed intake. Carcass traits were generally unaffected by lucerne inclusion. CONCLUSION: Lucerne meal may have greater potential for inclusion in diets fed to growing–finishing pigs than previously realized. To maximize pig performance, lucerne meal should be limited to less than 75 g kg?1 diet during the growing period, while it is possible to go as high as 150 g kg?1 diet during the finishing period without detrimental effects on performance. Copyright © 2008 Society of Chemical Industry 相似文献
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