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61.
M L Thonney T C Perry G Armbruster D H Beermann D G Fox 《Journal of animal science》1991,69(12):4866-4870
Boneless rib eye steaks from 32 Holstein and 32 Simmental x Angus steers were evaluated by 55 supermarket meat managers. Within breed, steers were divided into light or heavy initial weights. Within initial weight groups, steers were either implanted with Revalor or not implanted. Steers were slaughtered commercially when they reached a small degree of marbling, and rib eye steaks were cut from the carcass and stored at -20 degrees C until the day before evaluation. After thawing overnight in a 0 to 4 degrees C cooler, uncooked steaks were randomly assigned to positions on paper plates. Each of the 55 evaluators was then told to record whether each steak was from a Holstein or a traditional beef breed. The percentage identified correctly was 50.9 +/- .96, which was not different from being random. Steaks were later assigned to blocks of eight treatments and cooked to an internal temperature of 68 degrees C before six or seven participants evaluated steaks from each block. Sensory attributes were acceptable for all steaks. Steaks from Holstein steers generally were superior to those from Simmental x Angus steers. Steaks from steers with heavy initial weights generally were superior to steaks from steers with light initial weights. Steaks from steers implanted with Revalor were slightly less acceptable than steaks from unimplanted steers for several sensory attributes, but the difference in overall acceptability was minor and nonsignificant. All the differences were small, and may have limited commercial relevance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Traditional studies of electrophysiological correlates of behavior contain inherent high variability resulting from the arbitrary choice of behaviors, brain locations, and wave parameters. The operant control of neural events is a formal and systematic approach to the study of prespecified parameters and components of brain activity as they encode behaviors. Two studies in which the electrical activity of brain was the criterion for reinforcement demonstrate the acquisition, under such operant control, of two mutually exclusive behaviors or states which selectively alter evoked potential components. 相似文献
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Fox P 《Science (New York, N.Y.)》1913,37(940):25-40