Heterosis Effects on Jumping Height and Body Weight in Three-Way Rotational Crossing in Mice

Abstract

The three-way rotational crossing experiment has been conducted to evaluate heterosis effects on jumping height and body weight. Yonakuni wild mice (Y) and two genetic groups of CF#1 (C) and C3H/HeNCrj (H) laboratory mice were used as materials. Reciprocal rotational crossing was made by crossing C male Y female and Y male X C female to produce basic group designated G0 and G0’, respectively. The females of the G0 and G0’ were mated to the H sire to produce second generation (G1 and G1’), and at the following generation the replacement females were mated to Y or C sire according to the basic group to produce G2 to G3 and G2’ to G3’. Individual jumping height data at Wk6 and body weight data at 1 (Wk1), 3 (Wk3), 6 (Wk6) and 10 (Wk10) weeks of age were analyzed. The results showed that effects of genetic group, sex and interaction of genetic group by sex were significant (p<0.01) for jumping height. For males, 55.34%~79.17% and 54.46%~78.29% of heterosis were reached at G1 to G3 and G1'''' to G3’, respectively. While for females at G1 to G3 and at G’ to G3’, heterosis effects were 61.53%~80.42% and 47.79%~85.86%, respectively. For body weight, genetic group was a significant source of variation at all ages studied. Sex effect was significant at Wk3, Wk6 and Wk10, and interaction between genetic group and sex was significant at Wk6 and Wk10 (p<0.01). C sires resulted in the highest body weight of offspring, while H sires were the intermediate and Y sires were the lightest. The significant positive and negative heterosis effects for body weight were exhibited. Crossing involved the Y sires in addition to smaller maternal effects of Y dams tended to result in small heterosis. Keywords : Jumping Height, Body Weight, Heterosis, Rotational Crossing, Mice