UTILIZATION OF THE SEX-LINKED GENE FOR IMPERFECT ALBINISM (S-ASTERISK-ALS) .1. EFFECT OF EARLY WEIGHT-LOSS ON CHICK METABOLISM

The sex-linked gene for imperfect albinism (SALS) has been associated with slow early growth in some trials but not in others. Albino (59) and nonalbino (73) chicks were raised to 3 d of age to study early gro wth. At 3 d of age, plasma beta-hydroxybutyrate (beta-HBA) levels were measured and the chicks were euthanatized and dissected to measure li ver, gall bladder, and yolk sac weights. Fatty acids of the liver and the yolk sac were also analyzed. On average, albino chicks lost weight between hatch and 3 d of age and nonalbinos gained weight (-2.41 vs 0 .74 g/d, P < 0.01). At 3 d of age, Livers from albinos contained highe r (P < 0.01) levels of docosahexaenoic acid than those of nonalbinos, likely reflecting the dependence on yolk sac nutrients of albinos and on dietary lipids of nonalbinos at this time. Albinos had lower body t emperatures (P < 0.01), Liver weights (P < 0.01) and gall bladder weig hts (P < 0.05), and heavier yolk sacs (P < 0.01) than did nonalbinos. Plasma levels of beta-HBA were higher (P < 0.01) for albinos than for nonalbinos. At similar body weights, chicks of both genotypes had simi lar body temperatures, gall bladder weights, and plasma beta-HBA level s. Linear regressions indicated that in albinos weight loss is associa ted with larger yolk sacs, smaller livers, larger gall bladders, lower body temperatures, and higher levels of beta-HBA. Yolk sac utilizatio n seemed to be correlated with activation bf the digestive system. The inability of starving chicks to use the yolk sac nutrients while lipo lysis is taking place suggests that yolk sac absorption does not respo nd to Lipolytic hormones. Because under certain conditions a large pro portion of albinos (90% in this experiment) show the symptoms of the s tarve-out syndrome, the SALS gene could serve as a model for the stud y of this syndrome.