Effects of previous body weight level on rats' straight-alley performance

Reduced 90 male Holtzman albino rats to 75% or 90% body weight in 2 experiments. Experimental Ss (n = 45) received straight-alley training under these body weights while controls remained in their home cages. In a subsequent phase all Ss were run in the alley under 90% body weight. In Exp. I weights were adjusted for expected growth while in Exp. II weights were maintained at a constant percentage of ad-lib weight. In both experiments previous experience with 75% body weight facilitated subsequent instrumental performance under 90% body weight only if the 75% body weight had been experienced during straight-alley training. Ss which experienced different body weights in their home cages did not differ in subsequent straight-alley performance. It is suggested that differences in straight-alley learning are associated with different body weights. (PsycINFO Database Record (c) 2006 APA, all rights reserved).