Oyster Shells

[HntrInTheWoods]

So, I'm lucky enough to have free oyster shells to use for calcium, but I've yet to find a good way to crush them up (short of a sledgehammer and a big powdery mess), but I'm wondering, how much I should add? Got the girls on layer feed, but the shells could stand to be a little tougher. I buy about 100 lbs at a time.. read something about 4 grams a day, but how I figure out how much they eat a day is beyond me.. anyone used this method before?

 

[Pyxis]

I just offer oyster shell free choice in a separate feeder. No need to mix it into the feed; they will eat what they need on their own. It's better that way anyway because excess calcium in a bird's diet causes issues like kidney damage and failure, etc. That's why I feed all my birds a grower feed with oyster shell on the side. The birds that are laying take what they need, and those that are not don't consume excess calcium that they don't need.

 

[Egghead_Jr]

The daily intake doesn't mean that much, weekly intake is a better way to think about it. The hens store and use the calcium as needed for eggs and can replenish on a weekly or longer dosage.

For example, I toss a few handfuls of oyster shell on the ground every two weeks or so for about nine layers. They are not on layer feed, this semi-monthly dosage is all they get other than 1% calcium feed and insects free range.

 

[HntrInTheWoods]

I just offer oyster shell free choice in a separate feeder. No need to mix it into the feed; they will eat what they need on their own. It's better that way anyway because excess calcium in a bird's diet causes issues like kidney damage and failure, etc. That's why I feed all my birds a grower feed with oyster shell on the side. The birds that are laying take what they need, and those that are not don't consume excess calcium that they don't need.

Good point.. that was another question I was thinking about. Aflac was a female, until it came time to lay, and he decided to lose his voice and grow a curled tail feather. He's getting the same calcium intake, only he's no good way to get rid of it all.

 

[HntrInTheWoods]

I've also been crushing up their egg shells and adding it to the food. Can't always do that, though, as my compost bowl usually has coffee grinds in it. Not sure I want them that pepped up. Lol. I can tell the difference in their eggs for the next day or two.

 

[Ridgerunner]

The simple answer is you do not figure out how much they eat daily, they do. Chickens can get calcium from what is in their feed, from certain plants or veggies they eat, from creepy crawlies if they are lucky enough to catch something, or the rock they use as grit if your native rock has some limestone in it. The only way you have control over how much they eat is if you keep them confined so all they eat is what you give them, no access even to the ground. And you have to take into account all treats you feed them. It’s not easy to micromanage every bite. Most hens can manage how much they need if you offer a supplemental calcium separately and those that don’t need it don’t eat enough to harm themselves. If you mix it, especially with powder, you take that control away from them.

To make it even more fun, different chickens absorb calcium from their digestive tract differently. There are some variations in how their bodies work. Also the presence of other things in the food can affect how much gets absorbed and used. Some shell glands work better than others in applying that shell.

If all they eat, no treats or foraging, is Layer most get enough calcium out of that for good egg shells. If you are feeding them any treats or they forage for anything else, they may not be getting enough calcium. It’s not about how much calcium is in one bite, it’s how many total grams they average over several days, kind of like Egghead said.

If it’s one hen with thin shells then you don’t have a flock problem, you have an individual hen problem. One hen can have problems using the calcium she eats. If it’s consistent across your flock then you have a flock problem and should treat the flock.

Those things are hard to crush and you will get a lot of powder. Not for oyster shell but to crush something else, I built a really solid box out of 2xheavy lumber as a base and put a handle through a 2x4 or 2x6, can’t remember which, it’s been a while. I put a steel rod through a drilled hole in that 2x at one end and used it to pound what I was crushing. Just stand there and lift up and bring down.

 

[HntrInTheWoods]

The simple answer is you do not figure out how much they eat daily, they do. Chickens can get calcium from what is in their feed, from certain plants or veggies they eat, from creepy crawlies if they are lucky enough to catch something, or the rock they use as grit if your native rock has some limestone in it. The only way you have control over how much they eat is if you keep them confined so all they eat is what you give them, no access even to the ground. And you have to take into account all treats you feed them. It’s not easy to micromanage every bite. Most hens can manage how much they need if you offer a supplemental calcium separately and those that don’t need it don’t eat enough to harm themselves. If you mix it, especially with powder, you take that control away from them.

To make it even more fun, different chickens absorb calcium from their digestive tract differently. There are some variations in how their bodies work. Also the presence of other things in the food can affect how much gets absorbed and used. Some shell glands work better than others in applying that shell.

If all they eat, no treats or foraging, is Layer most get enough calcium out of that for good egg shells. If you are feeding them any treats or they forage for anything else, they may not be getting enough calcium. It’s not about how much calcium is in one bite, it’s how many total grams they average over several days, kind of like Egghead said.

If it’s one hen with thin shells then you don’t have a flock problem, you have an individual hen problem. One hen can have problems using the calcium she eats. If it’s consistent across your flock then you have a flock problem and should treat the flock.

Those things are hard to crush and you will get a lot of powder. Not for oyster shell but to crush something else, I built a really solid box out of 2xheavy lumber as a base and put a handle through a 2x4 or 2x6, can’t remember which, it’s been a while. I put a steel rod through a drilled hole in that 2x at one end and used it to pound what I was crushing. Just stand there and lift up and bring down.

A lot of really good info, there. Thanks for taking the time to respond. It doesn't seem to be an individual problem so far, as both layers are putting out the same quality of shell. I was so proud of how strong the first few eggs were, but I guess they'd been building up calcium for quite awhile.

 

[Ridgerunner]

If they wee pullets and the ones with the strong shells were the first ones laid, those eggs were probably pretty small compared to what they are laying now. If the shell gland is putting out the same amount of shell material, it's normal for the first eggs to have thicker walls than the later larger eggs. That's one reason it's not always a good idea to hatch the first eggs a pullet lays, the shells may be too thick for the chick to be able to hatch. There are several reasons not to hatch those eggs, that's just one of them.

If they are laying brown eggs, the first pullet eggs they lay will be the darkest they lay. One of the reasons for that is that the same amount of pigment on a small egg will be darker than if it is spread over a larger egg. Like everything else with chickens it's not all that simple, there are other reasons an egg gets lighter the longer the hen lays but that is one of them.