I realize I am new here, and appreciate all the information on this site from so many knowledgable dog owners, but I would caution the use of MSM because, while it is labeled a “natural” element, it is actually made from petroleum waste and methane gas. The actions of MSM are from the sulfur component. You can get sulfur from kale, or garlic (personally I prefer kale).
The body makes its own glucosamine sulfate: from the amino acid glutamine, a sulfur molecule, and a sugar molecule. You can feed the body foods high in glutamine: cabbage, for instance, beef, dairy, chicken.
There are also the stabilizers used in supplemental glucosamine sulfate: either sodium or potassium chloride. These additives can be 30% of the weight of the glucosamine. If the label says 4,000 mgs you will need to subtract 30% to know the actual milligrams of glucosamine sulfate you are getting. There currently are no labeling laws requiring the elemental amount of glucosamine sulfate per serving.
