Ashes - I have a lab that is now 5 years old and in the last year has developed allergies that has him itching constantly. We also feed him Purina Pro Plan chicken formula and recently switched to Inukshuk 26-16 chicken formula, but the allergies persist. We were going to try the Pro Plan salmon formula but it's interesting to hear that it didn't help in your case. It's also worth noting that Pro Plan changed their branding about a year or so ago which was around the same time the allergies began, which makes me wonder if they changed the formula or suppliers?
Our breeder has been adamant that these chewable wafers by NuVet Plus works wonders for ear infections. We tried them for our dog's allergies without any improvement but may be worth a try in your case. They ship to Canada but it's $55 USD + shipping, I think it worked out around $90 CAD all said and done for a 3-month supply. Here's a link (
https://www.nuvetlabs.com/order_new2...lus-wafers.asp).
Hope you find something that works.