Infectious agents are known to be a cause of subacute thyroiditis. Clinically affected patients exhibit goiter, dysphonia and dysphagia. Elevated levels of T4 may be present, while TSH concentration stays normal, and iodine uptake is reduced. A recent study conducted on eight dogs with proven high titers of T. gondii were investigated to see if their toxoplasmosis could affect thyroid morphology and function. Goiter was confirmed by ultrasound of the thyroid gland, and all dogs were treated with clindamycin for 30 days. A positive correlation was found between the titer of Toxoplasma antibodies, thyroid volume, and thyroxine concentration. After six months of treatment, two of the eight dogs developed hypothyroidism due to autoimmune thyroiditis. Thyroglobulin autoantibody levels were > 160% in spite of the euthyroid state that was present during the acute period of their toxoplasmosis. The study concluded that in some dogs infected with toxoplasmosis, thyroid morphology can be affected to the extent that autoimmune thyroiditis develops.
Reference: Castillo, Gámbaro, REDVET 7(#3), 1-11, 2006.

Traditional treatments for travel-induced excitement in dogs may be time-consuming, expensive, or associated with adverse effects. This study evaluated the efficacy of the ambient odor of lavender in 32 dogs with a history of travel-induced excitement in the owners' cars. Each dog was studied during travel in the owner's car to a familiar walking site. Two conditions of olfactory stimulation were applied: 1) Control condition during which the dogs were exposed to no odor other than that arising naturally from the environment. 2) Experimental condition during which dogs were exposed to the ambient odor of lavender. Dogs' behavior was recorded during the car journey for three consecutive days under both the control and experimental conditions. The percentage of time spent moving, standing, sitting, resting, and vocalizing in each condition of olfactory stimulation was quantified. Results showed that dogs spend significantly more time resting and sitting, and less time moving and vocalizing during the experimental condition. There was no significant relationship between the dog's behavior and sex, neuter status, day, or the order of exposure to each olfactory condition. Thus, aromatherapy in the form of diffuse lavender odor may offer a practical alternative treatment for travel-induced excitement in dogs.
Reference: Wells, JAVMA 229:964-967, 2006.