If you own a dog like the Pug then you may want to talk with your vet about common health conditions that can affect various breeds of dogs. For instance, hypothyroidism is a condition that is also referred to as Thyroid Hormone Deficiency. It typically occurs when there is a low production and release of the T4 and T3 hormones in the dog’s thyroid gland. The thyroid gland is responsible for producing the hormones, which are needed for your Pug’s body to maintain a normal metabolism. When these hormones are missing, your dog may develop hypothyroidism, which can cause symptoms such as lethargy, weakness, unexplained weight gain, hair loss, excessive shedding, poor hair growth, mental dullness, skin infections, intolerance to cold, tilting of the head to one side and even seizures or infertility. The disease is believed to affect dogs around 4 to 10 years of age. Your veterinarian Flower Mound, TX can provide you with additional information.