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
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,
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.
depresses the immune system which in
turn makes a pigeon much more susceptible to infection.
causes the proliferation of yeasts which were previously prevented from settling in the colon by
these beneficial bacteria.
can cause diarrhea and the loss of nutrients, especially magnesium and zinc.
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".