Asymptotic weight and maturing rate in mice selected for body conformation

Autor: Di Masso Ricardo J.; Silva Patricia S.; Font María Teresa
Sprache: Englisch
Veröffentlicht: 2000
Quelle: Directory of Open Access Journals: DOAJ Articles
Online Zugang: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572000000200016
https://doaj.org/toc/1415-4757
https://doaj.org/toc/1678-4685
1415-4757
1678-4685
https://doaj.org/article/003db2a008da4305a0597113c6fbc27c
https://doaj.org/article/003db2a008da4305a0597113c6fbc27c
Erfassungsnummer: ftdoajarticles:oai:doaj.org/article:003db2a008da4305a0597113c6fbc27c

Zusammenfassung

Growth patterns of four lines of mice selected for body conformation were analyzed with the logistic function, in order to provide baseline information about the relationship between asymptotic weight and maturing rate of body weight. Two lines were divergently selected favoring the phenotypic correlation between body weight and tail length (agonistic selection: CBi+, high body weight and long tail; CBi-, low body weight and short tail), whereas the other two lines were generated by a disruptive selection performed against the correlation between the aforementioned traits (antagonistic selection: CBi/C, high body weight and short tail; CBi/L, low body weight and long tail). The logistic parameters A (asymptotic weight) and k (maturing rate) behaved in CBi/C and CBi- mice and in CBi+ females as expected in terms of the negative genetic relationship between mature size and earliness of maturing. An altered growth pattern was found in CBi/L mice and in CBi+ males, because in the former genotype, selected for low body weight, the time taken to mature increased, whereas in the latter, selected for high body weight, there was a non-significant increase in the same trait. In accordance with the selective criterion, different sources of genetic variation for body weight could be exploited: one inversely associated with earliness of maturing (agonistic selection), and the other independent of maturing rate (antagonistic selection), showing that genetic variation of A is partly independent of k.