Well, I'm not 100% sure about that, but a week isn't a long time so as long as it was fresh feed would be more of a concern in my opinion (and maybe I'm wrong) and then changing to a complete duckling feed that was fresh would be a priority for me. Having Pekins often means supplementing, even when feeding a complete duckling feed. They're actually created more for meat than pets, but it's certainly possible to have them as pets. They grow so quickly and so big that they require more than other ducklings.Can an overdose of calcium do this? My brother fed the ducklings laying food for a week and I just switched them off today/yesterday but idk if that's the case cuz when I got out the shower I found a ducking sitting on my ducklings neck/back