three selection treatments were conducted for 12 generations in each of two base populations ( p and q ) : ( 1 ) increased nursing ability of the mother ( n12 ) , as measured by mean 12-day weight of eight young within a crossfostering set ( m ( p ) and m ( q ) lines ) , ( 2 ) increased adult ( 42-day ) body weight of the offspring ( w42 ) ( w ( p ) and w ( q ) lines ) , and ( 3 ) performance combining the two traits ( n12 and w42 ) into a selection index ( b ( p ) and b ( q ) lines ) .
C0004927
conducted
C0006147
nursing