Calcium supplements = harder to zip egg shells?

[Ruby Rogue]

Recently read an article suggesting that if you supplement calcium to your hens, in addition to the higher calcium layer feed, it can make it more difficult for the chicks to hatch (if you plan on hatching your eggs).

It was also suggested that a rough or bumpy egg shell is a result of extra calcium...

Does anyone have a take on this?

 

[Willow2253]

I have also heard that a bumpy eggshell is the result of extra calcium that gets deposited on the shell. It seems reasonable to me that a thicker shell would require more effort to hatch out of, but at the same time it could also protect a developing chick better than a thin shell.

 

[333113]

Recently read an article suggesting that if you supplement calcium to your hens, in addition to the higher calcium layer feed, it can make it more difficult for the chicks to hatch (if you plan on hatching your eggs).

It was also suggested that a rough or bumpy egg shell is a result of extra calcium...

Does anyone have a take on this?

Since I breed in part for backyard egg quality, I regularly take a look at the federal and state departments of agriculture literature, and also the practices of the big egg producers (because they don't want to spend more money on any ingredient, including calcium, than they need to for best results). Over time, I have noticed that most research suggests that it is highly unlikely that a hen will be able to absorb too much calcium to the point that it will negatively affect the egg; further, most hens mostly won't eat extra calcium unless they need it.

Also, some research I've read suggests that a hen's body "robs" her bones of calcium to produce eggs, the same as any other animal producing offspring, including us. So, too little is really bad!

You can really see a version of this in the leg color of good layers that have normally yellow legs--their legs get paler yellow when their laying volume increases, because the yellow goes to the yolks. Everyone who has backyard layers with yellow legs can observe it. This is acknowledged in the judging standards for the American Poultry Association, which suggests that poultry show judges should not take points off for paler yellow leg color in hens of laying age.

I suggest you give them a good layer feed with vitamins and calcium, not an all-flock feed which does not have extra calcium, and that should give you the best eggs possible out of your laying crew.

In my experience, if you have egg problems, it's best to look first at the most common problems: poor quality feed, insufficient water, insufficient vitamins and minerals including calcium, and stress (from overcrowding, predators looking in on them at night, etc.) Older hens (6+ years) will sometimes produce eggs that are not as robust as younger hens do. But most will still hatch! I know that some strains of birds (strains being not a breed, but a group of birds within a breed) may have been selected for show instead of for egg quality, so they may not be optimal egg producers.