Stories doing the rounds on various forums are about Mercadona Compy dog food. Various vets have contacted them having had dogs brought to them who were drinking to excess and resultant kidney failure. The cause appears to be after the company changed the packing from a tin to a cardboard package.The food therein has a too high salt content and it is the salt that is causing the problem.(Early Days)To be fair to Mercadona once they were made aware of this problem they took steps to withdraw it from the shelves and refund customers.Now this is in the last few days down in Southern Spain. With regards here in Catalonia all I can say is watch your dog if it drinks to excess or is peeing in the house and appears not to have control over its functions and it has been fed this COMPY dog food take it to the vet right away with a sample of the food in order it can be tested along with your dogs Blood as a urine test does not show up any problem with the dogs kidneys.Remember dogs may get water from other sources apart from its bowl so the excess urine is the first symptoms you will notice. This food is also available to cats so same observations apply. These problems could be a result of the contents or the new packaging. The olive press have just written about the problem. Link below and a link to the supermarket customer services.

http://www.theolivepress.es/spain-news/2012/02/24/supermarket-dog-food-link-to-e...

http://www.mercadona.es/corp/ing-html/atencion.html