If the room for rabbits is not heated, then you need to prepare for winter. First of all, you need to get rid of drafts, because even a small wind at minus 20 will blow any heat out of your rabbitry if there is at least some kind of small gap not closed up. All windows, windows, doors should be tightly closed. If your walls are brick (slag). check for cracks, all must be covered, putty. Check the presence of cracks or log walls for cracks, it will also be necessary to repair everything. The ceiling should be at least minimally insulated (for example, the ceiling and walls can be used to sheathe used corrugated cardboard. There will already be an effect, sheet foam is even better).
In cold rabbitries, water in the drinking bowls of the cage freezes in winter, the unfinished food freezes, rabbit manure freezes, which subsequently creates problems with cleaning the cages. In severe frost, the rabbits themselves freeze: in principle, an adult, healthy rabbit tolerates frost normally, but sick, weakened animals and small newborn rabbits can freeze.
Therefore, do not plan the birth of rabbits in the winter in cold, unheated rabbitry, as it is very likely that they will die from hypothermia.
It is necessary for rabbits to drive more hay into the cages so that it is sufficient not only for food but also for heating (in severe frost, rabbits burrow into the hay). Pour dry compound feed into the feeders, and pour warm water into the drinkers! To give root crops in such quantity that rabbits ate them right away, because half-eaten vegetables freeze and turn into a piece of ice. rabbits will not eat it.
Also, problems arise with cleaning the cells from rabbit manure, because all this "good" it does not drain into a sump as in summer, but freezes under a cage and it is very difficult to clean it from there. The situation is complicated if you have a multi-tiered arrangement of cells. Here rabbit warmer rescues at least to zero or the expectation of a thaw in winter. Some postpone the cleaning of cells from manure to spring.
If the rabbit in the room is protected even from the icy wind, then the street rabbit experiences not only frost, but also piercing wind. Therefore, rabbits in street cages should be tried to protect as much as possible from drafts. There should be enough hay inside the cages throughout the winter, and in the feeds of the compound feed, pouring the water into the drinking bowls is necessarily warm or in extreme cases you can use pressed snow. They do not heat street cells, as trying to somehow warm the rabbits in the cages on the street in winter. it is useless work and money in the literal sense of the wind!
How can rabbits be warmed in winter, especially in severe frosts?
There are not many options for heating, here are examples of some of them:
1) The most affordable and effective way. special heating lamp for 250-500 watts with a large bulb, transparent colors (if not, then you can use a red lamp). Such a lamp per day "will eat" from 6 to 12 kW of electricity. You can hang the rabbitry anywhere, the main thing is that it does not touch anything, because from contact, it will quickly fail. Also be careful in terms of fire safety. the lamp is very hot and therefore keep it away from anything that could easily catch fire.
2) Another option. electric heating stoves or oil heaters. Their efficiency is high due to the larger heat transfer area, but they consume electricity much more than lamps.
Thermoregulation. Another important point. When heated by electric heaters or lamps, you can save. setting the thermostat. This is a small device in the form of a conventional electric switch, with a temperature controller in the middle and a temperature sensor inside. It is connected to a circuit with an electric heater. The principle of operation is simple. setting the temperature at the device to 5 degrees, you start the cyclic process of heating the room. If the temperature in the room exceeds 5 degrees, the thermostat will turn off the electric heater. If the temperature drops below 5 degrees, the device will automatically turn on the electric heater. Thus, there is no need to constantly burn electricity for heating. But keep in mind that the effectiveness of this device directly depends on the presence of drafts in the room, i.e. if you constantly burn electricity for heating, and in the rabbitry you still feel cold, then there will be no sense in this device and in general in heating!