I have a batch of ducklings that are getting towards laying age (18 weeks). And another batch that are 7 weeks old. I have been feeding them a 20% protein ration (Purina Sunfresh Flockraiser). They free-range all day around and in a pond, too. I'm wondering if I can just keep feeding the same thing to all of them, and put a bowl of oyster shell out so that the laying hens have the extra calcium they need? Or will the younger ducklings (and the older drakes) eat it too? I'm not sure to what extent they self-regulate. I'd appreciate any advice, thanks in advance.
The younger ducks will end up eating the oyster shell. I am not sure whether they should have that or not, but I'm leaning toward no. Too much calcium at that age is probably not good. Otherwise, they should be fine all eating flock raiser. I like to give younger ducks a lower protein feed (with extra niacin) to prevent angel wing, so maybe cut your flock raiser with oats or another grain. But, that's a personal choice.
First, the disclaimer: I am no duck nutritionist. But, here is my general philosophy. You say they are free ranging all day. I say that assuming the forage is rich and varied, they are likely to be getting *most* of what they need from that. The concentrate you feed them is kind of like you or I taking vitamins along with a rich and varied diet. Which feed to use, and which supplements, become a bigger question during winter (when forage is thin) or in flocks that are managed on minimal space or always contained. That's not to say that it's not important, just that you can be less finicky when they have good access to forage. My ducks really don't seem to eat the oyster shell at all, but I keep offering it to them anyway, and they keep spilling it into their bedding and otherwise ignoring it. I don't have ducklings in with the flock at the moment, but I do have a drake, and so far he doesn't seem to have suffered harm from the oyster shell. On the other hand, as with vitamins in humans, the danger of overdose is often as bad as or worse than the danger of deficiency. So since they are foraging, they are probably finding lots of calcium and everything else they need in the food they are finding. If you're worried about it, you could separate the laying hens from the rest of the flock for 15 minutes a day or so and offer them the calcium supplement then. All of my adult ducks eat a 16% protein layer ration. When the ducklings go in with the main flock, I'll probably devise some way to feed them grower ration separate frome the layer until they are close to laying age. I have not had any problems with my drakes (I've had more than one in the past) eating the layer ration--it doesn't seem to harm them, and I still think that is because they have access to good forage. I know this is long and wandering, but I hope there's something in here that's helpful.