MDR1 ALERT FOR ALL COLLIE AND AUSSIE OWNERS:
This is a mutant gene which 70% of Collies and 50% of Aussies (minis to) are coming up positive. This gene can cause severe reactions with Ivermectin as found in Heartguard. There is a simple inexpensive test that is now available. Both of mine will be tested as soon I receive the kit. If your dog test negative, then Ivermectin can be given.
Info from the Australian Shepherd Genetic and Research: http://www.ashgi.org/articles/mdr1.htm
How do I know if my dog has the MDR1 mutation?
If your dog has already reacted to one of these drugs, it has the mutation. However, reactions can be so dangerous to your dog it is advisable to have the dog tested so you know whether it is sensitive before it receives any of the listed drugs.
What do the MDR1 test results mean?
This is a DNA mutation test. It will determine whether or not a dog has the MDR1 mutation and, if it does, whether it has one copy or two. The test report will provide you with the genotype for your dog, generally listed as Normal/Normal, Normal/Mutant or Mutant/Mutant.
Dogs with even one copy of the mutation should be considered sensitive to listed drugs. If your dog carries the mutation, provide a copy of the test results and a copy of the listed drugs to every veterinarian who treats your dog and let them know your dog cannot have those drugs.
What dogs should be tested and how often?
Since this is a DNA test, a dog only needs to be tested once. Due to the high frequency of the mutation in the breed and the variety of drugs to which dogs with the mutation can react, all dogs, including rescues of unknown parentage and Aussie-mixes should be tested. Their lives could depend on it.
The only exception is as follows: If both parents of a dog have tested Normal/Normal, they cannot pass on the gene and their offspring will not need to be tested. However, if a Normal/Normal dog is bred to one of unknown status or one that has even a single copy of the mutation, the offspring must be tested.
Dogs that do not carry an MDR1 mutation may safely receive the listed drugs.
How do I get the test done?
For those in North America, The test is available through Washington State University. Information can be found on their website: http://www.vetmed.wsu.edu/announcements/ivermectin/
Here is the site to order the testing kit, it is inexpensive and so worth it.http://www.vetmed.wsu.edu/depts-VCPL/index.aspx