Tinytreat's lionheads may only have 6 teats, but my Netherland Dwarfs have 8 (I was trimming claws yesterday, so I checked!!) I wouldn't worry too much about having "extras," unless they're really small, most does can raise 6 - 8 babies just fine (some of my Harlequins have managed 10 - 12 on their own!). With just one mating "out of the blue" like that, I think it unlikely that the doe was sufficiently stimulated to release huge numbers of eggs (you don't really want me to explain that, do you?) so you'll probably get a reasonable sized litter. An awful lot of does make a mess of their first litters anyway, so if you have any live babies at all, consider yourself lucky! Don't mean to sound like the voice of doom here, just giving you the perspective of a breeder with 20+ years of experience. Unless you get up at the crack of dawn, you will most likely never see the doe in the nestbox nursing her litter. Does usually nurse their babies at dawn, and maybe at dusk, otherwise, they pretty much ignore them. You will need to check the babies to see if they are getting enough milk - if they are, there will be a round white blob, like a large pea, where their stomachs are after the doe has nursed them. A first-time doe won't have a huge amount of milk, but her output does increase as the litter grows. As long as all of the babies are getting something in the first few days, they should be fine. At about day 3, the milk supply really increases, and suddenly all of the babies will look full to bursting!
If, and it really is a remote if, you need to feed some babies, most pet shops carry milk replacers for puppies and kittens. Read the labels, they will usually say if they can be used for rabbits and other small animals. You can feed with an eyedropper, or a small syringe, the important thing is that the kit wraps its tongue around the tip and sucks. If you try to feed faster than the kit can swallow, the milk can get into the nose and lungs, which can cause pneumonia and death. There are tiny nursing bottles that you can buy, but a newborn kit is usually a little too small to use one. You would need to feed several times a day, as the replacer is nowhere near as rich as the doe's milk is. The disturbance of nursing usually causes the babies to pee, with them all in the litter together, they only get wet (and thus chilled) once or twice a day. Hand fed babies pee more often (because they are fed more often) so they really should be kept separate from any that a doe is feeding, to reduce the disturbance and wetness of the nest.
During the pregnancy, the doe should be fed her usual ration. The general rule of thumb is about one ounce of feed per pound of body weight per day - so a 6 pound doe would get about 6 ounces of pellets each day. Fat does are less likely to breed, less likely to ovulate when bred, more likely to have kindling problems, more likely to die of ketosis or "fatty liver disease." Once the babies come, you will need to increase her feed, as lactation requires much more energy than mere maintenance does. Some people will increase the feed slightly during the last few days before kindling, it is important to make all changes gradual, as the doe may experience digestive upset from any sudden change. It is also a good idea to keep some hay available to the nursing doe, as she may eat her nesting material otherwise (including the fur, maybe giving herself "wool block" in the process!
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