Rage syndrome

Rage Syndrome, also known as Sudden Onset Aggression or (SOA) or Avalanche of Rage Syndrome, is a rare but serious behavioural problem that has been reported most commonly in the English Cocker Spaniel but also in a variety of other dog breeds. It is often misdiagnosed as it can be confused with other forms of aggression. It is thought to be genetic in origin and is inheritable. A variety of treatments are available, but will need to be tailored to the individual needs of the specific dog. The term rage syndrome is attributed to Dr. Roger A. Mugford, an English animal behaviour consultant.

The rage syndrome has no connection to rabies, for which its name is often mistaken (as the Latin translation stands for "rage").

The dog will suddenly act aggressively to anyone nearby, but minutes later will be calm and normal. The dog not seem to remember or realize what has taken place and may act immediately friendly to the person(s) whom they attacked. Attacks such as these cannot be prevented with training because it is a problem that the dog seemingly cannot consciously control. The attack will happen without apparent cause.

Shortly prior to an attack, their eyes can glaze over and go hard, followed by the dog snapping into alert mode before finally attacking. It appears to an outsider like an exaggerated form of aggression. Often a specific dog can have a certain trigger, such as the unexpected approach of people whilst he or she is sleeping.

Dr. Roger A. Mugford, to whom the term is attributed, identified that the problem starts on average at around seven and a half months old in English Springer Spaniels. However some of his research subjects showed signs at as early as three months and as late as two years. He did find however that many dogs displayed their first symptoms on or around one of the five critical learning periods identified in dogs. These occur at six weeks old, 12 weeks old, 24 weeks or six months, one year old and two years old.

It has been reported that rage syndrome was found to be more common in red, golden/blonde or black cockers than in any other colour and specific lines tend to have a higher occurrence. All solid coloured cockers tend to be at higher risk than their multi-coloured counterparts, with darker colours being most affected. It is most often associated with the show lines of the breed although cases have been found in the working lines as well. The colour of the dog may not actually be genetically related, but is more likely to reflect certain bloodlines. Cocker spaniel breeders do not commonly breed solid colours to parti-colours and so the two colour phases tend to be mostly distinct. Previous research in foxes in the 1970s linked particular coat colours with certain extreme behaviours and aggression.

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