title: Growth curve changes associated with long-term selection for body weight in Japanese quail.
abstract: Four quail lines were utilized to investigate growth patterns in quail. Three of these lines (P, T and S) had previously undergone long-term selection for high 4-week body weight, while line C was maintained as a nonselected control. Quail progeny from generation 37 and 38 breeders were fed diets containing 28% and 20% protein. Within each trial, the diet/line treatments were replicated 3 times with 12 quail per subclass. Body weight measurements suggested that the growth of all lines was best approximated by the logistic growth curve model. When fed a 28% protein diet the age at maximum growth (point of inflection) of selected lines was 4 to 6 days earlier than the corresponding age of controls. Similar rates of gain after 4 weeks of age between selected and control lines suggested that mechanisms influenced by selection for 4-week body weight in quail operate only during the period prior to the age at selection with little or no residual effect.
mesh_terms: D000704:Analysis of Variance; D000821:Animal Feed; D000818:Animals; D001835:Body Weight; D003370:Coturnix / Q000254:growth & development*; D004044:Dietary Proteins; D005260:Female; D008297:Male; D011784:Quail / Q000254:growth & development*; D012641:Selection, Genetic; D012737:Sex Factors; D013045:Species Specificity
chemical_list: D004044:Dietary Proteins