I find it very challenging to find the MAX calcium in LBP foods. Almost all the manufacturers list MIN calcium on their bags, which doesn't help when the problem is too much calcium (and overfeeding to produce too rapid growth)! I also find it frustrating dog food bags list As Fed whereas guidelines and studies list on a Dry Matter basis.
So far I have only found "Orijen Puppy Large" listing the min and max of 1.2%/1.5% on bag (1.3% MIN DM basis/1.7% MAX DM basis).
I called Wysong on March 24, 2014, and asked the MAX calcium level for Wysong Optimal Growth formula. The representative stated the MAX calcium level for Optimal Growth is 1.9% (I did not specify As Fed or Dry Matter (DM) basis. The Optimal Growth bag does not list calcium level, but states it meets AAFCO guide line for Growth (note, later remarks on change to AAFCO growth guidelines, which puts 1.9% as slightly over the new guideline of 1.8%).
I called Blue Buffalo and asked MAX calcium level for Blue Wilderness Large Breed Puppy (chicken). The rep stated 1.2%. I told her the bag lists 1.2% MIN, but I wanted the MAX for calcium. She stated the MIN and the MAX was 1.2% (which would be 1.3% DM basis). She explained it was a targeted formula and they aimed for 1.2% for both MIN and MAX in BWLBP. I asked her in several different ways to ensure she understood I wanted the MAX percentage and she definitely confirmed she understood I wanted the MAX, not the MIN and reiterated they were both 1.2%. Separately, I explained I had done a lot of online research to find maximums for calcium and thought it would help consumers if companies put on the MAX calcium content, as that is a key concern for LBP owners. She agreed and stated she had already emailed her tech department as we spoke (as I know it would be advantageous to companies with a good MAX calcium content to advertise the fact).
I have found in a lot of online research and correspondence that too much calcium is a key concern (and overfeeding). I have not found anything definitive about what constitutes too much calcium. So far I read AAFCO has or will update their "growth" standard to max 1.8%. However, this was from their meeting late last year or in January of this year, so I do not know if it is in effect and bags stating within AAFCO growth guidelines now meet this new standard (as noted above, Wysong Optimal Growth lists it meets AAFCO growth, but is 1.9% according to their rep, which whether that is As Fed or DM basis, either way is above AAFCO new guideline of 1.8%). The old standard (and possibly still current until officially adopted-I don't know as mentioned) was 2.5%. I mention this as a bag could state 1.2% MIN and AAFCO growth guideline and in actuality have 2.5% (or 1.8% if following new guideline). Which based on reading would be too high under the old guideline and at the upper limit for new guideline.
As for what is max acceptable level, I have not seen anything that ties to a definite percentage. 1.2% or 1.5% are often thrown out as an acceptable max. The notes from Recent AAFCO changes provide good insight (see pages 4, 9-10):
The AAFCO notes state: "based on comments and a publication10 demonstrating that some diets containing 0.88% to 1.04% Ca on a DM basis (2.2 to 2.6 g Ca/1000 kcal ME) when fed to medium- or large-breed puppies produced inhibited growth in 10- week growth studies compared to diets containing between 1.3 to 1.8% Ca "
The publication (footnote 10 in quote) AAFCO refers to is the following study:
Laflamme D. Effect of breed size on calcium requirements for puppies. Comp. Contin. Educ. Pract. Vet. 23 (9(A)):66-69, 2001.
The AAFCO notes also state: "Because of concerns for excess calcium to produce detrimental effects in growing dogs of large and giant breeds,10-13 the 2007 CNES deemed that additional restriction to the maximum limit for calcium was warranted and lowered the maximum calcium concentration to 1.8% DM."
The additional footnotes cited for reducing MAX calcium to 1.8%:
11 Hedhammer AF, Wu F, Krook L, Schryver HF, deLahunta A, Whalen JP, Kallfelz FA, Nunez EA, Hintz HF, Sheffy BE, Ryan GD. Overnutrition and skeletal disease: An experimental study in growing Great Dane dogs. Cornell Vet 1974; 64(Suppl. 5):9-160.
12 Goedegebuure SA, Hazewinkel HA. 1986. Morphological findings in young dogs chronically fed a diet containing excess calcium. Vet Pathol 1986; 23:594-605.
13 Hazewinkel HA, van den Brom WE, Vanít Klooster A, Voorhout G, van Wees A. Calcium metabolism in Great Dane dogs fed diets with various calcium and phosphorus levels. J Nutr 1991; 121(Suppl 11):S99-106.
I also found this American College of Vetrinarian Nutrition article (https://s3.amazonaws.com/assets.prod..._Nutrition.pdf
) that references the above LaFlamme study among others that states, "Both large and small breeds appear to grow safely when consuming diets that provide 1.0% to 1.5% DM calcium"
I also found The European Pet Food Industry Guideline (http://www.fediaf.org/fileadmin/user...guidelines.pdf
) lists 1.6% DM MAX calcium for early growth and 1.8% DM for late growth (which if I read the footnotes correctly, they use 6 months as the break point between early and late growth for LBPs. The guideline also references the above studies and states, "Weber et al. showed that when feeding a balanced food, a calcium level of 1.6 % DM from 9 weeks of age does not cause side effects. c, d During later growth up to 1.8% DM can be fed to all breed dogs including giant breeds with the exception of great Danes..."
As for me, I have decided to rotate between Orijen Puppy Large and Blue Wilderness Large Breed Puppy.
Definitely frustrating to research!
Happy to hear of other dog food MAX calcium levels on a Dry Matter basis!