There is a system sold by ARS (www.arssales.com) that uses their densimeter. If you do any collecting of semen or large horse breeding, its a very useful tool. If you don't do any collections and have no need of a densimeter, its very expensive and probably not worth it.
The Snap test is also avalible, from your vet I believe... its very difficult to buy an IgG test without a vet's help because all do require blood being drawn, and since that's a veterinarian practice its not usually avalible without a perscription. You certainly can find them, but some products and some companies that sell them limit their avalibility to vets and clients with vet's permission.
