Efecto de la restricción alimentaria sobre el crecimiento en dos líneas divergentes para variabilidad ambiental del peso al nacimiento en ratones

The aim of the genetic selection in animal breeding has traditionally been the increase in the mean of the productive traits. Selection for less sensitivity with respect to environmental effects as indicated by a low variation around the optimum trait value has benefits in the productivity and in the animal welfare and it is already and will be in the future one of the main targets of selection. The objective of this work was to analyze the influence of food restriction, which it is understood as an environmental challenge, on weight at different ages in two lines divergently selected for birth weight variability in mice. We also determined the interaction between the line and the diet. Animals of low line, which were feed ad libitum, present a body weight approximately equal in all generations unlike those of high line, which have present less weight. The dietary restriction has a negative effect on the body weight of the animals. We conclude that the animals of the low variability line are less sensitive to a change in feeding level than those of the high variability line.