Body weight and tail length divergence in mice selected for rate of development

Abstract

A series of mouse lines has been produced by 19 generations of restricted index selection for rate of development during early and late ontogeny. The selection program was based on an index with the following four replicated selection treatments: E+ and E– were selected to alter birth to 10‐day body weight gain while holding late gain for both selection lines constant; correspondingly, L+ and L– were selected to alter 28‐ to 56‐day body weight gain holding early gain for both lines constant. Herein, we characterize response to selection for growth rate by analyzing age‐specific mouse body weight and tail lengths and for growth curves using a logistics model. Selection on developmental rate has resulted in divergence in both age‐specific and growth curve traits. E+ and L+ lines reached identical weights during the late selection interval, then diverged to unique mature weights. E– and L– lines similarly achieved identical weights during late selection and diverged to unique mature weights. However, the shapes of early and late growth curves were significantly divergent, and at least two distinct growth patterns are shown to result from selection. Response in body weight gain was accompanied by similar, though less pronounced, change in tail length traits. Significant response during intervals of restricted growth was also found, especially in lines selected for late gain. The evolution of the growth trajectory under restricted index selection is discussed in terms of drift and available additive genetic variation and covariation. J. Exp. Zool. (Mol. Dev. Evol.) 288:151–164, 2000. © 2000 Wiley‐Liss, Inc.

The P2Y 13 receptor regulates phosphate metabolism and FGF‐23 secretion with effects on skeletal development

“…The higher endocortical osteoblastic parameters in 4-wk-old KO mice might indicate greater bone length rather than cross-sectional changes. This finding was confirmed with the measurements of tibia and tail length, which are easily obtained parameters for mouse growth rate (35). Both 4-and 10-wk-old KO mice showed significantly longer tails, while the length of the tibia was longer in KO mice by 10 wk of age.…”

Ontogenies in Mice Selected for High Voluntary Wheel-Running Activity. I. Mean Ontogenies

“…Thus, for the two ontogenies that changed in shape and position as a result of selection (wheel running and food consumption), drift only influenced the control line; however, for the ontogeny that changed only in position as a result of selection (body mass), drift affected both the selected and control lines. Other studies have observed similar effects of genetic drift on the genetic architecture of trait ontogenies (Rhees and Atchley 2000) and of correlated traits (Arnold and Phillips 1999;Roff and Mousseau 1999;Roff 2000;Phillips et al 2001), demonstrating that genetic drift can significantly influence the rate and direction of evolutionary change and that its effects in nonselected populations, at least for some traits may be stronger (but see Garland et al 2002).…”

Dehydration Impairs Physical Growth and Cognitive Development in Young Mice

“…Interestingly, the conducted DEXA total body scan showed that despite exhibiting the same daily energy intake, mice in the DEH group showed reduced physical growth compared to those in the CON group (Table 1). Specifically, the DEH mice exhibited a 5% (p < 0.05) reduction in lean body mass and a 9% (p < 0.05) reduction of their tail length, which is considered to be a standard growth indicator of rodent growth [23]. Therefore, these data suggest that dehydration incurs deleterious impacts on physical growth during the examined developmental period in young mice.…”