When you go to the vet to have your puppy spayed or neutered, they will do bloodwork to ensure the puppy is healthy enough to undergo surgery and anesthesia. When your veterinarian orders this bloodwork, they are checking to be sure all of the dogs’ levels are within what they consider to be “normal” range. If the blood cell count, platelets, enzymes or electrolytes are higher or lower than the expected range, this could be an indication that something is wrong.
One of the things tested is alanine aminotransferase (ALT).
“Alanine aminotransferase (ALT) is a clinical tool that can be used by veterinarians to better monitor liver health. This result is not associated with liver disease. ALT is one of several values veterinarians measure on routine blood work to evaluate the liver. It is a naturally occurring enzyme located in liver cells that helps break down protein. When the liver is damaged or inflamed, ALT is released into the bloodstream.” (Copied from Embark).
Every single dog that we have DNA tested and every single dog whose DNA tests we have reviewed have been positive for Low ALT… MOST SMALL DOGS HAVE LOW ALT ACTIVITY. This does NOT mean that they have liver disease or that they are at an increased risk for liver disease. It just means they have a lower baseline.
KNOWING that your dog is genetically predisposed to having Low ALT can be important to your vet because it can minimize concern when using that “normal” range to diagnose vitamin deficiencies or liver/kidney problems. Your vet can do bloodwork to establish what is the normal baseline for your dog, then use that number to gauge an increase or a decrease. (ex: If your dog is likely to have a lower than average resting ALT activity, an INCREASE in ALT activity could be evidence of liver damage, even if it is within normal limits by standard ALT reference ranges.)
The only way to know your dog has low ALT is through genetic testing, which is something we do for all of our breeding dogs.