The following rant is just for those that have ongoing egg shell issues and in no way intended to be critical of anyone who has posted. For the record, I'm not a proponent of the feed industry, I'm just trying to help.
Many factors contribute to shell quality, not just nutrition. Calcium and phosphorus must be in balance and sufficient D3 need be present to allow absorption of both. When adding calcium to the diet, the calcium to phosphorus ratio needs to be considered. Ca
should be about 10:1. Insufficient phosphorus can cause soft shells. Excess phosphorus can inhibit calcium mobilization from both diet and bone.
When things go awry, with laying or otherwise, it's time to go back to basics. Let's look at what we know.
Most manufacturers of chicken feed carry several lines of product for various ages of birds - starter, grower, finisher, layer, all flock, etc..
We also know that they are formulated to be a nutritionally
COMPLETE FEED. Since we're talking about egg issues, let's look at layer feed. Most of the layer feed labels I have read have a statement to the effect, "Feed as the sole ration to laying hens from onset of egg production during the entire production cycle. No other supplements are needed."
Then it is out of their hands.
They can't control how feed is stored, nor how long it is stored before being fed.
They don't come about those formulas and statements lightly. They employ poultry nutritionists that have the latest research at their disposal. They analyze each batch of feed to insure it has every vitamin, mineral, amino acid, fat, micronutrient and energy calorie known for body maintenance and good egg/shell production.
The levels of amino acids lysine and methionine as well as the calcium
hosphorus ratio is on every bag of feed.
In reading this thread, I've read about other things fed - treats, table scraps, scratch grains, calcium powder, injectable calcium, vitamins, kale, collards, peas, scrambled eggs, cracked corn, whole corn, BOSS, turmeric, cayenne, yogurt. All of those things are good and have a place if all is well, but if all is not well, it's time to rethink.
My suggestion, for those that have egg issues, check the manufacture date on your feed. If it isn't fresh (less than 2 months old) discard it and buy a fresh bag of feed and store it carefully in a cool dry place. Eliminate everything but clean fresh water and layer feed. Always make sure the feed contains no mold. If feed gets wet, feed it immediately, ferment it or discard it. If wet feed sits for more than a couple hours, discard it.
If you provide a free choice calcium source, it must be in a separate container and research shows that being large particle (oyster shell) it is more effective.
Never mix anything with the feed, especially a calcium source. They can't choose to eat it or not. Layer feed is already 4% calcium, mixing in calcium will throw off the balance of Ca/P/Mg/D3. It is entirely possible to have
too much calcium and cause egg shell problems. Top dressing feed with a calcium source can actually
cause soft eggs.
About 4 grams of calcium a day is required in the diet to maintain good shell quality and only 2 grams of that is actually deposited in the shell. That calcium comes both from the diet and the medullary bone. Intestinal absorption of calcium reaches over 70% while forming the shell. The calcium bone reserves are replenished during the time when the shell gland is in the inactive state.
If after going back to basics, the problem doesn't straighten itself out, the problem is probably not calcium related.
It can be
stress, an immature shell gland or a defective shell gland (in which case, culling is the answer).
The last time I had an egg with no shell, it came on the day of a dog attack.
Heat stress is often a cause of soft eggs.
No shells could be influenza or egg drop syndrome.
Soft shells could be egg drop syndrome, bronchitis, laryngotracheitis, or influenza.
Thin shells could be egg drop, bronchitis, cage fatigue, ochratoxicosis or fusariotoxicosis. The latter two are from fungus on grain or moldy feed.
Shells with pimples could be an excess of vitamin D.
Ridged shells- bronchitis
Odd shapes - bronchitis or Newcastle.
http://www.nutrecocanada.com/docs/shur-gain---poultry/egg-formation-and-eggshell-quality-in-layers.pdf
http://www.thepoultrysite.com/articles/1003/factors-influencing-shell-quality/
http://www.thepoultrysite.com/publi...dbook/16/thinshelled-eggs-and-shellless-eggs/
@Simple M What is your flock's primary feed? How is the barn ventilation and temperature.
