Streptococcus gallolyticus

It was in the 1980's that I borrowed some of my friend's stock birds because I wanted to breed some young ones from them. I kept each pair confined to a box of 8 ft2 until they layed in order to be certain of the offspring's parentage. After not even 2 weeks of confinement I opened the cages and noticed to my dismay that almost none of these birds was able to fly.
What did I do and what was I dealing with here? What was I to tell my friend? The strange part of it was that none of the birds looked ill which is the reason why none of them were treated with any antibiotics. Yet, in spite of withholding antibiotics all of the birds eventually recovered. It was years later when I read an account of this type of infection and the cause of it.
While some workers call the organism responsible for this illness Streptococcus bovis it would probably be more accurate to refer to it as Streptococcus gallolyticus since it is the latter which is more likely involved in human and animal infections. 1
The experience of August 10, 2005 is now just a repeat performance of many such previous experiences. Although these 2 birds had no appetite to eat on August 10 the red checker resumed eating August 11th as did the blue checker although they still could not fly. A sudden inability to fly is symptomatic of swelling of the breast muscles due to extremely long flight or damage to these muscles by an infection of Streptococcus gallolyticus (bovis). Since these 2 birds did not over exert themselves their condition must be the result of an infection which also explains the symptom of inappetence which is not present after over exertion. The return of appetite occurred without the use of antibiotics on the next day.
This was an indication that the acute stage of this infection was past but the inability to use their muscles of flight was suspected to be due to lesions of necrosis in the pectoral muscle, similar to those seen after experimental infection. The need for antibiotics to help the birds overcome such an infection may not be necessary because 37% of pigeons develop antibodies to these micro-organisms without having shown any of the clinical signs of infection. There are at least 5 strains of different virulence of this bacterial species. The response to an infection depends on the virulence of the infection and the bird's innate immunity. A low virulence and a high innate immunity will result in no symptoms following an infection while a high virulence and low immunity leads to a sudden death. Although both, amoxicillin and ampicillin, are effective in treating an infection of Streptococcus gallolyticus and reduce the morbidity, reaching for the bottle of antibiotics at the first sign of this infection may lead to resistance of these bacteria to the antibiotic used.
Besides the development of resistance are the "side effects" these powerful drugs have. Antibiotics do not only kill Streptococcus gallolyticus organisms but also many other beneficial bacteria such as Lactobacillus acidophilus and Bifidobacterium bifidus. These 2 species are often found in probiotic mixtures because their presence in the colon helps in the development of a strong immune system. Since there are trillions of the various micro-organisms in the colon there will always be some which are resistant to any given antibiotic. An antibiotic kills all micro-organisms which are sensitive to it and consequently selects for those micro-organisms which are resistant to it. Once a bacterium is resistant to an antibiotic it will share this resistance with not only other bacteria of its own kind but also with other unrelated bacteria. The net result is an antibiotic which is quickly losing its effectiveness.
The best treatment option is to reserve these drugs for only very serious infections.
This, however, may not be the most desirable alternative if one ranks the flying performance of racing pigeons higher than everything else. Pigeons can perform better with antibiotic support as some of these drugs have effects which can be regarded as "doping". One of my friends administered Emtryl® on a weekly basis not because his pigeons were extraordinarily susceptible to canker but because he wanted to stimulate their appetite and get these cocks ready for the next race.
Other antibiotics have other "side effects" and some of these can be considered "doping effects".
The administration of antibiotics is therefore useful if one wants one's birds to perform better than their constitution would allow naturally. Better performance in turn can result in increased sales or improve one's self esteem if one succeeds in fooling oneself.
Summary:
Unless one is confronted with a very virulent strain, the use of antibiotics is not indicated. Mild strains of Streptococcus gallolyticus are very wide spread. They are present in many lofts for which reason this organism is considered "an opportunistic pathogenic agent in pigeons".
This page was last up-dated on August 11, 2005

Below are your comments:
No comments yet

To the top