Oyster Grit

Nahbois92

Chirping
5 Years
Apr 7, 2016
3
1
52
New Zealand
Hey all.

I was wondering is any one could tell me if it is possible to make Oyster Grit? It is really expensive so would like to make it cheaper. Is it just crashed oyster shells?
 
I see people keep mentioning egg shells as a calcium supplement. They are an excellent supplement. Chickens get calcium from various things they eat, chicken feed, some green stuff, and some critters they eat if they are lucky enough to get to eat critters. Some rocks, like limestone, contain a lot of calcium. They may get all they need just by using the rock they use as insoluble grit. They need calcium for general body maintenance, plus hens that are laying need quite a bit of extra calcium for the egg shells.

It’s possible you don’t even need to supplement their diet with calcium if they have a natural source. Your egg shells will tell you how they are doing. If the shells are hard and thick, they are getting enough. If the shells are thin or soft, they need a supplement. I think it is a good idea to always offer a calcium supplement on the side. If they need it they seem to know to eat it. If they don’t need it a little can last a really long time. Each flock goes through oyster grit at their own pace.

There is a potential trap with using just egg shells. They don’t digest all the calcium they eat. A lot goes right on through their bodies and out the rear end. That helps make compost made from chicken manure really good for your garden, a lot of plants need calcium to grow and produce. Chickens also use some for general body maintenance. If the only calcium they are getting is from egg shells, it’s a losing proposition. But again let your egg shells tell you how they are doing. They can get calcium from other sources. If the egg shells are hard and thick, whatever you are doing is working. Supplementing with egg shells may be all you need.
 
It's very cheap. If you only look on the shelf the packaged Oyster shell of far over priced. Ask at the counter for bulk. I've yet to go to a feed store that did not sell it in bulk where you or they scoop out as much as you want into a plastic bag. Some keep it in back so ask at counter.

Th effort to crush oyster and mollusk shells with a mallet would not be worth any "savings" in my opinion. For me I'd have to find the shell then spend hours smashing it. Can't remember exact amount but bulk crushed shell is around 25-35 cents a pound. 10 lbs lasts me from fall downsizing to spring. Maybe I go through 20lbs a year so at most that's $7?
 
Since OP is in New Zealand oyster shell may be more expensive than in the states.
As suggested saving the egg shells (bake them first) and feeding them back to the chickens is one option.
Others option(s) might be something like liquid calcium that can be added to the water or feeding vegetables that naturally have a high calcium content.


http://www.amazon.com/Vetark-Zolcal...en-20&linkId=7db8f94f9c8f6891faffcef0598211d7
 
Hey all.


I was wondering is any one could tell me if it is possible to make Oyster Grit? It is really expensive so would like to make it cheaper. Is it just crashed oyster shells?


New Zealand?....how awesome! :cool:

Oyster shell is ground up....Oyster Shell. I don't know the economic structure of New Zealand, but here in Colorado, the oyster shell supplement is pretty cheap.

I for one, would be very interested in the chickens that you keep and see your flock.

Here's an idea for you...do you have access to coral sand where you live?

Coral sand is composed mostly of calcium carbonate....which is what Oyster Shell is composed of as well.

...and I'd like to see your birds...hint hint.
 
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I see you’re from New Zealand. That’s why you call it oyster grit. Seems we each have our own way to name it. The Brits call it soluble grit, in the US we just call it oyster shell. Thanks for giving your location, that helps with many questions. And welcome to the forum.

Oyster grit is just crushed oyster shell. It’s very inexpensive here in the States, there are vast dead reefs of oyster shell that can easily be collected and crushed.

There are two different kinds of shell on various sea critters. The hard shells on oyster, clam, mussels, crabs, and such are made mostly from calcium. You can crush use any of these to provide extra calcium to your laying hens.

The other is the chitin. That’s the softer translucent material on shrimp, crab underparts and other critters. It’s mostly a protein and will not add calcium to their diet. It will add protein but it’s a protein that is not easily digested. Still they will eat it and get some benefit from it. I feed mine shrimp shells.

Some parts are part calcium and part chitin, the harder they are the more percent calcium. A lobster might be a good example of a critter that has both. The claws are mostly calcium, the shell mostly chitin, but the shell has both.

If you have a source of hard shell, oyster, clam, mussel, whatever they should not be that hard to crush and use. You don’t have to turn them into powder, pieces the size of a green pea work well.

How do you plan to crush them? If it were me, I’d probably use a section of 2x4 and stand over them on a hard surface. I’ve used that method to crush other things before, but not shell.

Don’t confuse oyster grit with insoluble grit as the Brits call it. Here we just call it grit. I have no idea what you call it. That’s the stuff they use in their gizzard as teeth to chew their food. They will use practically any rock they find for this, but the insoluble grit we buy is generally granite, a waste product from quarries. Oyster shell cannot be used as soluble grit. Not only is it too soft and brittle, the digestive juices dissolve it.

Good luck and again welcome.
 
New Zealand?....how awesome!
cool.png


Oyster shell is ground up....Oyster Shell. I don't know the economic structure of New Zealand, but here in Colorado, the oyster shell supplement is pretty cheap.

I for one, would be very interested in the chickens that you keep and see your flock.

Here's an idea for you...do you have access to coral sand where you live?

Coral sand is composed mostly of calcium carbonate....which is what Oyster Shell is composed of as well.

...and I'd like to see your birds...hint hint.

I sure am. From the far south so it is very cold.
It seems to be about $20 for a $5kg bag but I was doing a little bit of research last night and seem to have found a source that I can not get it for $12 for 10kg - I am so happy about that.
Here is a wee pic.I already have on my computer from when we set up there run. We currently have 20 chickens but as some turned out roosters we are re-homing 5 roosters :)
 
Thank you so much everyone. New Zealand seems to charge a fortune for everything but I have found that I can get 10kg for $12 so I am beyond happy about that.
I found that crushing up the egg shells once cooked is helping too. Although we are in autumn they have slowed right down with us reaching our -3 degrees etc but fingers crossed with there deep bedding and food and water available all the time maybe we can have eggs though the colder days hehe.
 

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