Genetic Influences on Mouse Growth at 23 and 32°C

Abstract

Two inbred strains of mice and the reciprocal Fl hybrids between them were reared in a temperate or in a hot humid environment. There was an age-related environmental effect on the rate of increase in body weight. Between 2 and 5 weeks the rate· of weight gain was more rapid in the heat but at all other ages weight gain was more rapid in the temperate conditions. Periods of rapid growth were associated with low intra-strain variation in body weight.