Minimum Calcium content

[farmerbrowne]

Howdy all,
I was wondering if anyone has documentation on the min required calcium content needed for a hen 19+ weeks old, as well as a 19+ week old rooster. all i can find is this meme and the book they are claiming to reference is nearly 200 bucks

 

[JacinLarkwell]

@U_Stormcrow

I think that actively laying hens need at least 3% calcium, but I'm not 100% sure

 

[U_Stormcrow]

Understanding that the studies were designed for prime age commercial layers, about 4% calcium +/- but averaging around 4% is what needed to provide a production red, leghorn, or the like its calcium needs while laying. There is some variation by individual, but you needn't panic if you are only getting 3.6% average or 4.5% average for your hens, if you feed them seperately.

The calcium needs of pre-production birds of all ages, and roosters throughout their lifespan, is about 1%+/- within a narrower range. Typically 0.9 - 1.2 %, with at least 40% as much potassium (0.4%) but benefiting them up to about 0.6% potassium.

Over longer time scales, higher calcium abmounts have the potential to be damaging particularly to hatchlings and adoloscents, but also to roos. How much damage depends on time, dosage, and when the excess began - much like smoking - some people suffer no ill effects, some people get mild cancers, some people genm numerous, and severe, cancers. No predicting it in advance in any individualy - but statistically, the more you smoke, the younger you start, the less filtered the cigarettes, the more likely you are to develop one or more severe forms of cancer.

From those well understood studies principles, and analogies, we infer that bird that produce smaller eggs than prime production layers, or less frequent eggs than prime production layers, (or both) need less calcium to support their egg shell production. How much less??? Nobody studies that - there's no money in the knowledge.

Whch is part of why so many of us BYCers recommend feeding an "all flock"-type formulation (around 1% calcium +/-) together with free choice calcium (usually in the form of oyter shell), becuase studies have repeatedly shown that chicks are generally (there are individual exceptions, - but generally) able to self regulate their calcium needs when a source is available.

 

[farmerbrowne]

for prime age commercial layers, about 4% calcium +/- but averaging around 4%

Ive often heard the amount of calcium in commercial feed (mine being 4.24%) is too much for them. The roosters as you state need much much less. I ask this as my homemade feed is 0.11%

 

[farmerbrowne]

I do however, supply free choice oyster shell

 

[U_Stormcrow]

Ive often heard the amount of calcium in commercial feed (mine being 4.24%) is too much for them. The roosters as you state need much much less. I ask this as my homemade feed is 0.11%

Limitations of the study - first year commercial layers, no concern for long term health.

Now, that said, I have a tiny amount of anecdotal evidence that an extra percent or two in adult birds over the course of a year or two generally results in almost undetectable damage to the birds. Also, phosphorus acts as a calcium buffer, and the type of calcium matters - dicalcium phosphate has much fewer associated problems when fed to excess than calcium carbonate, for instance.

 

[JacinLarkwell]

Limitations of the study - first year commercial layers, no concern for long term health.

Now, that said, I have a tiny amount of anecdotal evidence that an extra percent or two in adult birds over the course of a year or two generally results in almost undetectable damage to the birds. Also, phosphorus acts as a calcium buffer, and the type of calcium matters - calcium phosphate has much fewer associated problems when fed to excess than calcium carbonate, for instance.

I can add on your findings. I have two males that are nearly 10, and several thar are over 2 and unless I cut them open, I wouldn't know they're eating layer. They behave no differently than when on Any other feed. Now, I'm sure that their kidneys may not be as pristine as a bird that's never eaten layer feed, but they certainly seem happy and healthy even after 10 years or so of layer feed