- Jun 4, 2011
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there are allegedly a few bloodlines that have produced dogs that had an issue. It's been more "individuals" that had a sensitivity than it being a breed issue. But some test for it.
no matter which method you use, routine testing is going to be important. I think effectiveness may be lowered because of over-use. the "every 30 days" is to cover the companies butt - just in case you are a little late, your dog will be covered and they won't have to pay out on their guarantee.
So, you have years of commercial use, on a slightly accelerated schedule and it's not surprising that some populations of parasites may eventually develop an immunity.
no matter which method you use, routine testing is going to be important. I think effectiveness may be lowered because of over-use. the "every 30 days" is to cover the companies butt - just in case you are a little late, your dog will be covered and they won't have to pay out on their guarantee.
So, you have years of commercial use, on a slightly accelerated schedule and it's not surprising that some populations of parasites may eventually develop an immunity.