喂饲辐照饲料和高压饲料大鼠子代生长发育及神经反射、学习记忆功能比较

Comparison of growth,neural reflex,learning and memory ability between offspring of rats fed with irradiated feed and with high-pressure steam sterilizing feed

目的对喂饲经辐照和高压两种不同灭菌处理方法饲料大鼠的子代的生理生长、神经反射指标和学习记忆功能进行比较研究,为实验动物饲料灭菌方法的取舍、限制提供参考依据。方法试验设2个组,分别为喂饲高压蒸汽灭菌饲料组和喂饲辐照灭菌饲料组。给亲代大鼠分别喂饲高压蒸汽灭菌饲料和辐照灭菌饲料10周后,合笼交配,自然分娩产仔。每组选15窝,每窝选8只仔鼠,测试仔代大鼠生理生长指标(张耳、开眼、长毛、出牙时间)和神经反射指标(平面翻正、前肢抓力、悬崖回避、听觉警戒、负趋地性、视觉发育、空中翻正);于6周龄时,各组选择雄性大鼠15只分别进行避暗试验和穿梭试验,测试学习记忆功能指标(避暗潜伏期、错误次数、穿梭主动回避次数、主动回避时间)。实验数据以SPSS软件统计分析。结果避暗试验中,摄食辐照饲料大鼠在记忆巩固和记忆消退试验中,潜伏期(150.0±62.7)s和(126.6±61.8)s均长于摄食高压饲料大鼠(65.9±83.9)s和(56.0±53.7)s(P<0.05),错误次数(0.2±0.4)次和(0.5±0.6)次均小于摄食高压饲料大鼠(0.9±0.9)次和(1.4±0.9)次(P<0.05),其余各项生理生长、神经反射指标和学习记忆功能指标差异均无统计学意义(P>0.05)。结论喂饲辐照饲料和高压饲料的大鼠子代生长发育及神经反射方面差异无统计学意义,被动记忆方面喂饲辐照饲料子代大鼠表现优于喂饲高压饲料。

Objective The experiment aims to provide reference for the choice and restriction of experimental animal feed sterilization methods by comparing the physiological growth,neural reflex,learning and memory ability of the offspring of the rats fed with high- pressure steam sterilizing feed and irradiated feed. Methods The experiment consisted of two groups,the group of rats fed with high pressure steam sterilizing feed and the group of rats fed with irradiation sterilizing feed. The parental rats were fed with high pressure steam sterilizing feed or irradiation sterilizing feed respectively for 10 weeks. Then the rats mated in the cage and gave birth naturally. 15 litters,with 8 offspring for each litter,were selected for each group for determining the physiological growth index（ the time of ear opening,eye opening,hair growth and tooth growth） and neural reflex indicators（ plane righting reflex,the forelimb grip,cliff avoidance,auditory vigilance,negative geotaxis,visual development,and air righting reflex）. At the age of 6 weeks,15 male rats from each group were subject to dark avoidance test and shuttle test to determine their learning and memory ability. The experimental data were analyzed by SPSS. Results In the dark avoidance test,the incubation of the offspring of the rats with irradiated feed at the stages of memory consolidation and memory fading [（ 150. 0 ± 62. 7） s and（ 126. 6 ±61. 8） s] was significantly longer than that of the rats with high- pressure steam sterilizing feed [（ 6 5. 9 ± 8 3. 9） s and（ 5 6. 0± 5 3. 7） s]（ P〈 0.05）. At the same time,the numbers of errors of the offspring of the rats with irradiated feed at the stages of memory consolidation and memory fading（ 0. 2 ± 0. 4 and 0. 5 ± 0. 6） were less than those of the rats with high- pressure steam feed（ 0. 9 ± 0. 9 and 1. 4 ± 0. 9）（ P〈 0.05）. The differences in physiological growth,neural reflex and the other indexes of learning and memory ability were not statistically significant（ P〉 0. 05）. Conclusions There are no obvious differences in the growth and neural reflex of the offspring of rats with high- pressure steam sterilizing feed and irradiated feed. The offspring of the rats with irradiated feed have better passive memory than those of the rats with high- pressure steam sterilizing feed.