Having seen numerous postings over the last few weeks on RI in pythons, I thought I would post a few comments on the subject. Laura made a good observation a few days ago about environmental stressors in captivity and on the fact that the causitive organisms are ever present.
More than 95% of all captive boas and pythons are already carrying the gram negative bacteria that are the cause of most RI’s in captive boids. If one of the pythons in a collection has an RI, then the entire collection has already been exposed to that causative organism well before the symptoms showed. This would be primarily from previous exposure from the source it was acquired, or from simple maintenance procedures within your own collection. The reason that these organisms typically don’t cause issues is that unless the animal is physically or environmentally stressed in some manner, the organism is kept in check by the snakes immune system. The main stressors include sub-optimal temps, high or low; sub-optimal humidity, high or low; or lack of security causing nervousness and stress, etc., to name a few. A healthy, non-stressed python will not acquire an RI from contact with an infected python. If it does, then it is under the same stressors that compromised the initial infected python originally.
Seeing that the organisms are already present, if RI’s are showing up in a collection, then look for the stressor source that is compromising the animal and weakening it’s immune system to the point that the bacteria are able to multiply unchecked. Too low humidity is probably almost as common a stressor as temps that are too low or too high as far as respiratory issues with pythons. The biggest issue is in the winter when temps are kicked up slightly in collections and the warm cage interiors rapidly drive humidity out into the low humidity room. Because the amount of water vapor the air can hold increases rapidly with temperature, the relative humidity actually decreases rapidly with increasing temperature, unless the evaporation potential can be met. This means that unless the rate of evaporation can keep up with the demand for moisture brought on by the rising air temperature, there will be a rapid net loss in relative humidity within the cage. Unless you have a good source of cage humidity in the drier winter months, you can sometimes risk RI’s in your collection even when maintaining optimal temps. And that brings up the point that you should never lower humidity on a python with an RI. Low humidity air dries the lung tissue of tropical pythons and this damages the tissue making it more susceptible to bacterial infection. I’m not saying keep it overly high, but in the 60% to 75% range depending on the species. When temps are good, sometimes the appearance of initial RI symptoms are caused by lung irritation due to low humidity, and many times it can be resolved before progressing into an actual RI by raising the cage humidity and maintaining temps in the proper range. Usually this initial phase manifests itself as opened mouth breathing without the presence of heavy mucous as is seen with an actual RI. However, observe closely so the appropriate action can be taken if the problem progresses.
Kelly
