My name is***** and I am happy to help. Such a young ***** ***** that has low energy certainly is concerning, as that is most unusual. I would first like to caution against he use of aspirin, as dogs have a much lower tolerance than people for its tendency to cause stomach
irritation and ulcers. Plus, with it not having helped, it seems that his issue may not be pain. If Jack ever does have a painful condition in the future, there are much safer and effective options for pain in dogs.
At such a young age, one of the first places I would look is a stool sample, as intestinal parasites are common in young dogs. No matter how high quality a food you may feed, intestinal parasites have the potential to leach nutrients from the diet and lead to failure to thrive, poor energy levels, and other problems. Thus, I would scoop up a fresh sample of stool and bring it down to your veterinarian for analysis.
Other conditions that may cause weakness and is more common in small terriers than other breeds is Adisson's Disease. Addison's Disease stems from the body's inability to synthesize the important stress hormone, cortisol. Some dogs with Adisson's begin with poor energy levels before at some point going into a full out crisis. Since there are other systemic diseases that can lethargy and poor energy, I would begin with a general blood screening, what we call a "wellness profile. This includes a blood chemistry, blood cell count, and thyroid level.
This segues nicely into the next common cause for lack of energy in dogs, hypothyroidism
, the inability of a dog's thyroid glands to produce adequate amounts of thyroid hormone. As an important metabolic mediator, hypothyroidism leads to sluggish metabolism and poor energy level. Since thyroid level commonly is including in most general blood screening tests, you may assess for this an other disease with one simple blood test.
Lastly, I would focus on cardiac disease, as cardiac disease is a common source of poor energy levels, as it results in inadequate blood circulation. Not all cardiac diseases are necessarily discovered on physical examination, as in the case of electrical conduction disorders. Thus, if you veterinarian has not yet heard any abnormalities with his stethoscope, I would consider having an electrical strip of the heart run called and ECG, looking for any electrical conduction issues. The most common kid is called AV block.
If you would like to read more about these diseases, please feel free to visit the "Diseases A-Z" link to my website below. I wrote most of the articles and all of the possibilities I discussed here are available for you to read more about:
Also, please feel free to print out this consultation for discussion with your veterinarian.