Recently a friend brought this to my attention:
I almost killed my dog with fish oil.
The post is very concerning and I do supplement fish and flax oil with my dogs. However, there are a few things about this post that sketch me out. If you google vitamin e deficiency and fish oil and dogs, a lot of website reference this post.
This person only made one post on the forum. They never followed it up and I cannot find a webpage for the OP[original poster] specifically. The OP also does not say what they feed their dog, just that it is balanced. It leads me to believe the dog may have had a vitamin e deficiency due to a dietary problem.
I asked four veterinarians I work with and none of them had ever heard of fish oil depleting vitamin e. A coworker and I scoured the internet for answers. As I mentioned above, several websites referenced this post, but I couldn't really find a solid answer when it comes to fish oil and dogs.
What I did find was that it has been studied in humans and prolonged use of fish oil can deplete vitamin e in people.
"Prolonged use of fish oil supplements can cause vitamin E deficiency, which is why vitamin E is added to many supplements"
"Levels of vitamin E may be affected by seizure medications, zinc and fish oils."
I haven't found any solid scientific proof that supplementing vitamin e when giving fish oil is necessary in dogs. I have also not been able to find other instances of other dogs getting sick/vitamin e deficient due to fish oil.
I found a few forums and websites that referenced giving a dose of anywhere from 100iu-800iu.
I decided it couldn't hurt to add a small amount of vitamin e to my dog's diets. I buy human fish oil that is not anything fancy, I basically buy whatever brand is on sale at whatever store I happen to be at when I need it. I am giving my dogs 200iu once a day. I will likely continue to give it, but if I stop I will try to remember to update this post.
Should you give vitamin e oil with fish oil? I can't answer confidently yes, or no. I encourage anyone reading this to research for themselves. I do think if you feed a raw or homemade diet you should consider supplementing unless you know the vitamin levels in your food. Kibble is preserved with mixed tocopherols, usually including various vitamin e sources.
I have been feeding fish oil since October/November of 2013 and my dogs have suffered no issues from it. If anything they have really benefited from both the fish and the flax oil - their coats are shiny and their skin isn't flaky and dry.
Anyway, this post probably just further complicates the issue because I can't give a solid answer, but hopefully it was somewhat useful.
-I stopped giving vitamin e. I really think Vitamin E Deficiency is an issue if you do not feed a complete diet. I still feed a balanced good brand of kibble - Canidae. I am not worried that fish oil will deplete my dog's vitamin e stores.