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The objective of the current study was to create an in vitro model that duplicated the development of PSE pork. Postrigor pork chops with various pH values and normal color were vacuum-packaged, and heated at approximately 42 degrees C for various times (0, 15, 30, 60, 120, or 240 min), or heated to temperatures that occur early postmortem (34, 37, 39, or 42 degrees C for 60 or 120 min) in a water bath. Chops were cooled and allowed to bloom, after which changes in Minolta and Hunter color values were assessed, and purge loss was determined. Warming postrigor pork with normal color and pH to early postmortem body temperature for various times successfully duplicated the characteristics of PSE pork. After 60 to 120 min at 42 degrees C or above, chops with pH < 5.8 lightened until L values were similar to those typical of PSE pork (Minolta L = 61.0). Change in chop color depended on length of time the samples were warmed, as well as on pH. Below 34 degrees C, temperature had no (P > or = 0.28) effect on color (Minolta L, a, b, and Hunter L*, a*, b*); however, at higher temperatures, color change depended on pH and warming time. A comparison of the time and temperature relationships for changes in lightness and purge suggested that the mechanisms of the two processes are not identical. The similarities in the dynamic range of color change, change in absolute color values, and time frame for changes in vitro and in vivo suggest similarity of the processes creating PSE in a carcass and in the in vitro model. 相似文献
75.
Lappin MR Breitschwerdt EB Jensen WA Dunnigan B Rha JY Williams CR Brewer M Fall M 《Journal of the American Veterinary Medical Association》2004,225(6):893-6, 879
Anaplasma phagocytophilum DNA was detected in blood of clinically ill cats from Massachusetts (n = 4) and Connecticut (1) by use of polymerase chain reaction assay and DNA sequencing. All 5 cats were allowed outdoors, and Ixodes scapularis were found on 3 cats. Clinical signs of fever, anorexia, and lethargy resolved quickly after treatment with doxycycline or tetracycline. Serum samples from each cat reacted with A. phagocytophilum morulae via an indirect fluorescent antibody assay; positive antibody titers persisted even after 21 to 30 days of treatment with tetracycline. To the authors' knowledge, this is the first report of A. phagocytophilum infection of domestic cats in North America. Results suggest that infection with the organism may be associated with clinical illness in some cats. 相似文献
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A survey of the production and use of animal manures in England and Wales. I. Pig manure 总被引:7,自引:0,他引:7
Abstract. A survey was undertaken in 1996, by postal questionnaire sent to a stratified sample of 1500 pig producers in England and Wales; 576 (37%) responded. The survey provided data on manure production, manure storage and application strategies (timing, techniques and nutrient recycling to crops).
Total pig manure production, in England and Wales is estimated to be at about 10.03 m t per year, with about 45% as slurry and 55% as FYM, according to this survey, where calculations have been based on undiluted outputs of excreta. About 45% of slurry is stored in above-ground tanks or earth-banked lagoons. Above-ground tanks most commonly held an amount of slurry equivalent to 3–6 months production, but earth-banked lagoons were more variable in capacity and over 20% could hold more than 9 months production of slurry.
Annual statistics on fertilizer use indicate that farmers make little allowance for the nutrient content of manures. However, the results of this survey suggest that farmers generally make a genuine effort to allow for the nutrients applied, but that they currently fail to be assured by the advice available to them or their confidence is lacking for other technical reasons. Autumn represents the peak period for spreading, with 30% of slurry and 50% of FYM applied at that time. 相似文献
Total pig manure production, in England and Wales is estimated to be at about 10.03 m t per year, with about 45% as slurry and 55% as FYM, according to this survey, where calculations have been based on undiluted outputs of excreta. About 45% of slurry is stored in above-ground tanks or earth-banked lagoons. Above-ground tanks most commonly held an amount of slurry equivalent to 3–6 months production, but earth-banked lagoons were more variable in capacity and over 20% could hold more than 9 months production of slurry.
Annual statistics on fertilizer use indicate that farmers make little allowance for the nutrient content of manures. However, the results of this survey suggest that farmers generally make a genuine effort to allow for the nutrients applied, but that they currently fail to be assured by the advice available to them or their confidence is lacking for other technical reasons. Autumn represents the peak period for spreading, with 30% of slurry and 50% of FYM applied at that time. 相似文献
78.
Omololu John Idowu Soumaila Sanogo Catherine Elizabeth Brewer 《Communications in Soil Science and Plant Analysis》2017,48(15):1781-1791
Three arid soils (clay loam (CL), sandy clay (SC), and sandy loam (SL)) were amended with pecan waste products (ground pecan shells (PSHs), ground pecan husks (PHUs), and ground pecan shell biochar (PSB)), at a rate of 45 Mg/ha, packed inside cylindrical rings and kept in a humid chamber for 4 weeks. Measurements taken included volumetric moisture content as the soil dried out for 7 days, wet aggregate stability (WAS), permanganate oxidizable carbon (POXC), nitrate-nitrogen, extractable phosphorus (Olsen-P), and water-extractable potassium (K). Significant effects of soil texture, soil amendment, and their interaction were observed for all measurements. Generally, the amendments led to significant improvement in Olsen-P, K, POXC, and WAS, while amendments’ impacts on soils of different textures varied. Short-term moisture retention was dependent on soil texture, with PHU and PSB treatments having higher soil moisture retention in SL and CL soils but not in SC soil. 相似文献
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