Originally Posted by KsKingBee
I will recheck my labels, but I think all crumbles, (at least I know that layer does), have crushed limestone in it for calcium. That may be grit enough, however fine as it is?
Well, not exactly. I use three different products, poultry grit, chick grit, and oyster shell, depending on what the birds need. You can see the difference in the photos below:
In this picture, poultry grit is on the left. Chick grit is in the center. Oyster shell is on the right. The main difference between the two grits is the grain size. Grit is a rock granule that ends up in the bird's crop for grinding food. Some kinds of food, such as chick starter, go through okay without supplemental grit. Harder and coarser foods such as whole grains, cracked corn, seeds and hard-shelled bugs (I think dried mealworms should be in this category) need grit in the crop in order for the bird to break it up and get the nutrition from it, and to avoid a crop impaction which I think can happen to chicks from too many dried mealworms and which I know can happen from seeds and coarse feed. The poultry grit that I use happens to be made from insoluble granite, so it doesn't throw off the birds' calcium level.
Because poultry grit is coarse, it can be too big for baby peachicks. Here's a close up:
The poultry grit is on the left, the finer-grained chick grit is on the right. I wouldn't start it too early -- the bag says start at two weeks -- after that, I mix a little in with the medicated chick starter to gradually expose them too it. The grains will stay in the crop, and excess (don't want them to get too much) will generally pass through the intestines. When they are bigger, they get the poultry grit, which I toss into the adult feed occasionally. The birds take what they need and the rest gets left behind. Free range birds find their own, but that doesn't happen here, and my pens don't have a lot of grit-sized pebbles for them to choose from, so I provide the grit. I sometimes feed some scratch grains for variety, and cracked corn in the winter for warmth, so it is essential for them to have grit to be able to digest those foods.
The calcium in crumbles is not going to be effective for grit. First,. it is too small to be effective. Second, even if it were large enough, it wouldn't do the job. Calcium supplements are too soft (Mohs hardness 3 - 3.5) to effectively grind hard feed such as seeds, corn & insect shells) and it breaks down in the presence of digestive acids. Third, adding too much supplemental calcium can lead to kidney problems. Here's a close-up photo with the chick grit on the left, and the calcium supplement on the right (in this case, it is an oyster shell & coral calcium commercial product).
You can see how much more rounded the whiter calcium supplement grains are -- the grit is more angular, and has a completely different chemical composition. The calcium is softer and rapidly breaks down in the bird -- not what we want in a grit. Nor do we want the calcium overload that would follow.
Here's photos of each product with the bags:
Right tool for the right job, right?