Relationship of Sex Separation to Individual Variation in Body Weight and to Experimental Error

Becker and Berg (1959) examined the relationship between experimental sensitivity and the genetic structure of the experimental population and its environment. Using body weight data from chickens up to 8 weeks of age, they concluded the phenotypic variance of sexes raised separately was less than for the mixed sexes. Their results indicated an increase in experimental efficiency in nutrition experiments may be obtained by brooding each sex separately. Experimental error may be divided arbitrarily into three portions: first, the variation inherent in an experimental population to which the treatments are applied; second, the variation which arises within treatments as a result of the treatment influence; and third, that variation arising from non-treatment environmental effects being unevenly distributed within the experiment. Acknowledging the presence of the third portion in all experimental work, the objective of this study was to observe the influence of raising sexes separately and mixed on the inherent …