LAD is a disease that has been investigated only in the last ten years.  It is not a common disease, but where it does appear its end result is death of the puppy or dog.
     LAD is a genetically inherited disease that is a result of the inability of the puppy to absorb, or metabolize, zinc, a needed mineral.  Some breeds are able to undergo zinc supplementation to their diets and are successful in reversing the disease.  Unfortunately, Bull Terriers do not seem to respond to zinc treatments, and are euthanized usually before they are seven months old.  There have been cases where owners have nursed their charges to prolong their lives, but the puppies/dogs eventually succumb to terminal pneumonia, not living beyond fifteen months of age.
     There are a number of symptoms (clinical signs) that will warn a breeder that the puppy is in danger.  The breeder here is the one in the best position to note these symptoms since the onset of this disease occurs when the puppy is about 4 to 6 weeks of age.  The breeder will need to note that the smallest puppy will be at greatest risk, it will show little pigmentation to its skin being a light pinkish color. The other puppies, as well, will need to be observed closely for problems in nursing from the mother.  There will be difficulty in digesting food as the puppies go from nursing to more solid food, and the growth rate is severely retarded.  The puppies should be examined closely for inflammation and infection of the area around the paws, the foot pads and the skin over the elbows and hips.  There is a progressively worsening inflammation of the skin in this area.  There have also been reports of aggressiveness by the affected pup towards its litter mates, to the point of having to separate the pups from each other.
     A veterinarian must be consulted if this disease is suspected in any of the pups.  There are other diseases that have the same clinical signs as LAD, and only by having a veterinarian doing the required tests can a proper diagnosis be made.