Pigeon fanciers often confuse Streptococcus with paratyphoid, often resulting in the wrong treatment. In normal pigeons the bacteria Streptococcus gallolyticus can occur in the intestines without making the pigeon ill. It is only when the bacteria passes through the intestinal blood barrier, in other words, enters the blood circulation system, that the more serious symptoms can occur. Typical is the sudden death of a pigeon that looked completely healthy just a few hours before. This is due to the fact that the bacteria, once in the blood, can very quickly cause serious inflammation in organs and muscles. In experimental infection of healthy pigeons whereby the bacteria was directly injected into the blood, all the pigeons died within a few hours of being injected. Antimicrobial treatment just after the contamination couldn't save the pigeons from dying.
With milder contaminations the main symptoms are difficulty with flying (caused by reactions to the inflammation in the muscles and tendons), general malaise, slimy faeces, and loss of appetite. Sometimes the only symptom is the death of one or more pigeons even though the rest are completely healthy. It is not really known which factors are responsible for the bacteria entering the blood. On the one side there is the high infection load in the vicinity and factors such as stress, intestinal infection etc... Stress is a very important factor by this complaint. It seems that streptococcosis also has an epidemiologic patron, that is to say, that multiple pigeons from the same colony all show symptoms at the same time. This suggests that the degree of infection and most probably the factors that cause the contamination through the specific bacteria strains (the streptococ sort) are also of great importance. That's why it is recommended that all the pigeons are treated, even if only a few pigeons show signs of being contaminated. The exact diagnosis can only be given at the autopsy. The best chance of achieving valuable information is through an autopsy of a sick or dead pigeon. This is definitely the case with this illness, but is actually the case when diagnosing problems in the pigeon colony. A probable diagnosis can be made on the basis of the symptoms. After treating the condition for two days the symptoms often disappear. It is still recommended that the complete duration of the treatment is respected. The treatment consists of applying amoxicillin or ampicillin individually or to the drinking water for ten days.
The treatment works extremely well and the problems with the affected pigeons are soon resolved. Even though it has never been scientifically proved, I have learned from experiences in my surgery that colonies with paratyphoid problems (whether or not they are cured or suppressed) are often more easily affected by streptococcosis. One of the explanations for this could be the intestinal damage salmonella causes, ensuring that streptococcus is easily transferred into the blood circulation. The complaint often occurs during the racing season and can be a reason for poor performances, and often for losing first-class pigeons from races even though the race caused no problems for other fanciers. This is due to the pain that the inflammation causes in the muscles and tendons. Sometimes even large chunks of the muscle are lost through the heavy inflammation and are replaced with connective tissue (muscle necrosis). It is obvious that such pigeons, depending on the severity of the necrosis, are not suitable to take part in the races. If you catch it in time and can prevent this terrible muscle necrosis, then it is usually possible to achieve good results with these same pigeons.