Macadamia nuts are high in fats so feeding your dog large amounts of them may result in canine pancreatitis since dogs are not designed to process that much fat.
Pancreatitis is an inflammation of the pancreas that causes the organ to malfunction.
It is painful and uncomfortable for your dog to have pancreatitis. In addition to losing his appetite he may feel tender and swollen in his stomach and he may vomit frequently.