What's the optimal humidity level for an enclosed rabbitry? It's staying about 10 degrees warmer in there, but the humidity gauge says it's 78% humidity. It's misty out today though to.<br /><br />__________ Sun Nov 20, 2011 8:22 pm __________<br /><br />I stumped ya, huh? :lol: I should add probably, that we do have an exhaust system, with 2 small cold air returns, one on each end. The exhaust system is on a timer, so the air is being circulated, and refreshed several times throughout the day/night. We've got a couple big windows in there, and windows on the doors, and nothing is steamed, or foggy, but we're just curious because the % seems so high.
Ok, I actually found this info, which was a great read, and I think we're actually ok in there.
Humidity. Rabbits are sensitive to very low humidity (below 55 percent) but not to very high humidity. This may be explained by the fact that wild rabbits spend much of their lives in underground burrows with a humidity level near saturation point (100 percent).
The rabbit has more to fear from abrupt changes in humidity. Constant humidity is therefore the best solution, and this will depend on the housing design. French breeders find 60 to 65 percent humidity levels successful, using only auxiliary heating in winter.
While the humidity level does not seem to trouble the rabbit in moderate temperatures, this is not so with temperature extremes.
When the temperature is too high (close to the rabbit's body temperature) and humidity is also high, not much latent heat can be exported as water vapour through evaporation. The result is discomfort which can be followed by prostration. Very hot spells with near 100 percent humidity can cause serious problems. Unfortunately this is common in tropical climates during the rainy season.
When the temperature is too low and humidity close to saturation point, water condenses on poorly insulated walls, especially at so-called "heat bridges". Water is a good heat conductor and so the cold becomes more penetrating, causing heat loss in the animals through convection and conduction. Digestive and respiratory disorders often follow. When the surrounding air is cold, excess humidity modifies the secretion and viscosity of the mucus protecting the upper respiratory apparatus.
Air which is too dry (below 60 percent relative humidity) and too hot is even more dangerous. Not only does it upset the secretion of mucus but the ensuing evaporation shrinks the size of the droplets carrying infection agents, enabling them to penetrate more easily the respiratory apparatus.
Ventilation. The rabbitry must have a certain minimum of ventilation to evacuate the harmful gases given off by the rabbits (CO2), to renew the oxygen and get rid of excess humidity (evaporation, exhalation) and excess heat given off by the rabbits.
Ventilation needs can vary enormously, depending especially on climate, cage type and population density. Ventilation standards for temperate climates based on several French studies are given in Table 50. This table combines the various parameters (temperature, air flow, humidity) to determine optimum air flow per kg of rabbit live weight. If there is an imbalance, especially between air flow and temperature, accidents like those illustrated in Figure 24 occur.
It is relatively easy and cheap to measure temperature and humidity, but exact air flow measurement requires sophisticated, expensive, hard-to-get equipment such as a hot-wire anemometer (a revolving-cup anemometer is not sensitive enough). However, the producer can estimate the rate of air flow near rabbits by using a candle flame, as shown in Figure 25.
High ammonia air levels, 20 to 30 parts per million (ppm), greatly weaken the rabbits' upper respiratory tract and open the door to bacteria such as pasteurella and bordetella. To keep NH3 levels down, ventilation can be increased. The risk is then overventilation, with all the negative consequences illustrated in Figure 24. A more effective solution is to limit NH3 production from fermenting floor litter (droppings and urine) by removing the litter quickly or keeping it dry. The maximum permissible NH3 content in the air rabbits breathe is 5 ppm.
Here's a link to that site, and the page I pulled from.
http://www.fao.org/docrep/t1690E/t1690e08.htm#TopOfPage
Ok, I actually found this info, which was a great read, and I think we're actually ok in there.
Humidity. Rabbits are sensitive to very low humidity (below 55 percent) but not to very high humidity. This may be explained by the fact that wild rabbits spend much of their lives in underground burrows with a humidity level near saturation point (100 percent).
The rabbit has more to fear from abrupt changes in humidity. Constant humidity is therefore the best solution, and this will depend on the housing design. French breeders find 60 to 65 percent humidity levels successful, using only auxiliary heating in winter.
While the humidity level does not seem to trouble the rabbit in moderate temperatures, this is not so with temperature extremes.
When the temperature is too high (close to the rabbit's body temperature) and humidity is also high, not much latent heat can be exported as water vapour through evaporation. The result is discomfort which can be followed by prostration. Very hot spells with near 100 percent humidity can cause serious problems. Unfortunately this is common in tropical climates during the rainy season.
When the temperature is too low and humidity close to saturation point, water condenses on poorly insulated walls, especially at so-called "heat bridges". Water is a good heat conductor and so the cold becomes more penetrating, causing heat loss in the animals through convection and conduction. Digestive and respiratory disorders often follow. When the surrounding air is cold, excess humidity modifies the secretion and viscosity of the mucus protecting the upper respiratory apparatus.
Air which is too dry (below 60 percent relative humidity) and too hot is even more dangerous. Not only does it upset the secretion of mucus but the ensuing evaporation shrinks the size of the droplets carrying infection agents, enabling them to penetrate more easily the respiratory apparatus.
Ventilation. The rabbitry must have a certain minimum of ventilation to evacuate the harmful gases given off by the rabbits (CO2), to renew the oxygen and get rid of excess humidity (evaporation, exhalation) and excess heat given off by the rabbits.
Ventilation needs can vary enormously, depending especially on climate, cage type and population density. Ventilation standards for temperate climates based on several French studies are given in Table 50. This table combines the various parameters (temperature, air flow, humidity) to determine optimum air flow per kg of rabbit live weight. If there is an imbalance, especially between air flow and temperature, accidents like those illustrated in Figure 24 occur.
It is relatively easy and cheap to measure temperature and humidity, but exact air flow measurement requires sophisticated, expensive, hard-to-get equipment such as a hot-wire anemometer (a revolving-cup anemometer is not sensitive enough). However, the producer can estimate the rate of air flow near rabbits by using a candle flame, as shown in Figure 25.
High ammonia air levels, 20 to 30 parts per million (ppm), greatly weaken the rabbits' upper respiratory tract and open the door to bacteria such as pasteurella and bordetella. To keep NH3 levels down, ventilation can be increased. The risk is then overventilation, with all the negative consequences illustrated in Figure 24. A more effective solution is to limit NH3 production from fermenting floor litter (droppings and urine) by removing the litter quickly or keeping it dry. The maximum permissible NH3 content in the air rabbits breathe is 5 ppm.
Here's a link to that site, and the page I pulled from.
http://www.fao.org/docrep/t1690E/t1690e08.htm#TopOfPage
