We just lost one of our outside dogs. He was a beautiful Lab/Rot mix. Looked like a full blood Rotti but had the personality of a Lab. We had both our outside dogs tested for heart worms and both tested positive. Could not afford the treatment. We live on a fixed income that does not stretch. I know it's just a matter of time before the other one dies also. She's Rot/Chow mix and solid red short hair. Very pretty dog and had rather be petted than eat. Now she's grieving for her companion. They have been together for 6 years. If you can get them tested early enough before they get the worms, you can give them medication for prevention. So please get your animals tested when they are young and can put them on medication for prevention of the heart worms. It hurts to lose a pet.