calcium levels in hen's feed

[VanUnamed]

hello, i have one question for you guys.
I make my own feed, and add specific additives according to the type of animal being fed.
I use wheat, sunflower, sometimes oats, barley, field peas as the base and then I add a protein
concentrate (it is essentially freeze dried and powdered hog skin) to make feeds go up in protein.
I don't have analysis on the grains being fed, but i found to get good results with the levels I do apply.
the issue is, i am unsure about CALCIUM.
i did read this https://www.backyardchickens.com/articles/why-you-should-stop-feeding-layer-feed-now.73535/ ,
I do add this product to the mix https://calciufurajer.ro/ which lists – gaini ouatoare 8-10% = Laying hens.
so that works out at 800/1000g / 10kg of feed. even though if you do the math at around 9% works out to be
the 4G of calcium a layer hen needs every day, what is confusing to me is this. I have 20 hens, and i get about
9~11 eggs per day. that means, some hen may get twice the calcium she needs, also, i have no idea who lays and
who does not, eggs are all different. there might be a few hens that maybe lay twice a week and get a massive amount
of un-needed calcium.
So my question is, should i cut this additive in half? Pullets on pasture that have just started to lay occasionally,
made a good egg-shell, even though for "regular chicken" only 1.9% is needed.

Thank you in advance.

 

[Perris]

If you make a source of calcium available in a separate bowl, they will help themselves to however much they need individually. Common sources are oyster shell, other shells, limestone (old poultry handbooks recommend old limestone mortar) - and milk.

 

[Lilbitsnpieces]

I make my own feed and simply keep oyster shell in separate feeders..

 

[Ridgerunner]

I also suggest offering a calcium source on the side, not in the feed. The ones that need it tend to eat what they need, the ones that don't shouldn't eat enough to harm themselves. And you are not force feeding them more than they need if it is offered on the side. The ones not laying still need some calcium for body maintenance so all of them may take a bite or two.

Chickens can get calcium from different sources other than what we offer them: some plants, creepy crawlies they catch or we feed them as treats, even the rock they use as grit if it is calcium based, like limestone. They may be getting enough calcium from the other stuff they eat so they may not even eat the supplement, or the supplement may disappear pretty quickly, so don't get worried if the calcium supplement doesn't get eaten as much as you think it should. Let your egg shells tell you how you are doing. If the shells are hard and thick enough you are doing OK. If they are thin or soft they may not be getting enough.

Look at the flock' s eggs, not just one specific hen's. It's possible one specific hen could be having a problem. I don't want to treat the entire flock for an individual hen's problem.

 

[VanUnamed]

I don't know where these oyster shell can be found. Here, you just buy this in buckets or bags, it's granules like table salt. so i should put this in a separate feeder?
Also, why commercial feed has even more calcium that recommended then?

 

[U_Stormcrow]

I don't know where these oyster shell can be found. Here, you just buy this in buckets or bags, it's granules like table salt. so i should put this in a separate feeder?
Also, why commercial feed has even more calcium that recommended then?

Put this stuff in a seperate dish. Just like we in the US often offer Oyster Shell in a seperate dish. Not only will that save you the hassle of trying to make your feed 10% above target (so that when you thin it out with 9% this product you end up back at your desired 100% ratio) (Because 1 x 1.1 x.91 = 1.001 (close enough).

Oyster Shell is almost entirely calcium carbonate. They are comparable products.

And don't worry about your chickens getting "too much" calcium one day and "not enough" the next, based on whether they lay or not that day.

By offering free choice, the birds will self regulate - something studies say they do quite effectively when offered a seperate calcium source. Moreover, the bird's own bodies are designed to maintain calcium levels over short periods - nobody knows in advance whether or not a bird will lay in the next 12-18 hours so they can offer "extra" calcium (or withhold calcium) for the period.

Trust your birds, they are far better at being chickens than we are.

 

[VanUnamed]

so basically hens know how much they need? it's surprising as humans can easily malnourish themselves and not even realize it.
But i take the dosages for growing pigs and meat chickens still hold true? its 0.9% and 1.9% respectively.