Most Commonly Physical Diseases In Dogs

Narcolepsy

Narcolepsy (sleep attacks) with concomitant cataplexy (loss of muscle tone in all skeletal muscles except muscles needed for breathing) is an uncommon clinical sign occurring in dogs. The signs in themselves come from an imbalance in the sleep–awake neurotransmitter system in the forebrain and brain stem. In the dog population, narcolepsy with cataplexy occurs both as a genetic disease and as a sporadic acquired disease. Even though the clinical signs in different dogs suffering from different forms of the disease are undistinguishable from each other, the cause of imbalance in the affected neurotransmitter system seems to differ. In the hereditary genetic form, the receptors on the postsynaptic nerve cells are mutated and malfunctioning, while in the acquired form, the production of the neurotransmitter substance seems to be too low. 

Weakness – tiredness – fatigue – listlessness

These are signs most commonly related to physical diseases in dogs. Weakness is a sign commonly encountered in small animal veterinary practice. It is termed episodic when elicited by exercise and dissipated by rest. Although weakness unrelated to exercise is an appreciated clinical sign in human psychiatry, it is not easy to reveal such aetiology in canine weakness. As several metabolic, endocrine, cardiovascular and neuromuscular diseases may result in weakness, work up of a weak dog calls for an evaluation of electrolyte and hormonal balances as well as cardiovascular and neuromuscular function. Adrenal insufficiency (Addison’s disease), hypothyroidism and Myasthenia gravis are examples of differential diagnoses in a dog that develops unexpected severe weakness at almost any age. Weakness at an older age could also be due to degenerative processes, including canine cognitive dysfunction.

Anxiety – fear – avoidance – flight 

These signs might be caused by injuries and physical diseases. Although anxiety and fear are commonly seen as inherent behavioural manifestations in many dogs, it must be appreciated that injuries and physical diseases may cause or perpetuate signs of anxiety and fear. Avoidance and flight in a dog that has not exhibited such signs before indicate a possibility that an ongoing disease process or current or earlier exposure to physical harm might be involved. Any traumatic injury, causing pain somewhere in the body, may provoke anxiety and fear. But also to ‘experience’ an epileptic seizure or loss of breath is capable of inducing anxiety and fear. Anxiety is also described as an early clinical sign in lysosomal storage diseases such as fucosidosis, an inherited disease in English springer spaniels, for example. Relief of pain before and after operative procedures has received increased attention in veterinary medicine. In order to recover fast and completely, pain relief is almost as important as anaesthesia during surgery. 

Aggression 

Aggressive behaviour might also arise out of external ‘stimuli’. Misdirected aggression cannot be excused but rather explained by painful processes that the dog may either relate to a person or to a situation. Clinical situations and veterinary visits might either be so harmful that aggression is warranted or just be a situation in which a dog with strong dominance aggression ‘tests’ his position. Sudden and strong pain may elicit biting that is an expression of avoidance rather than aggression. Relief of pain is as important for reduction of misdirected aggression as for anxiety