If a lamb is orphaned, or its mother refuses to care for it, somebody must act as its mother or it will die.
Undertaking care for such a lamb is not easy, as well there is a high cost factor for formula, nonetheless it is a rewarding experience and the lamb will be extra friendly as a result.
Before much else is done the owner should ensure the lamb is dried off, its naval dipped in iodine, and that it receives colostrum. Colostrum is a mothers first milk and it contains the first antibodies the lamb needs for survival and strength. In some cases the lamb may have had some colostrum before the loss of its mother, but if not, and no other ewe has recently lambed (and could be milked) lamb colostrum can be purchased from a veterinarian, livestock feed store, or even other sheep producer. In an emergency calf colostrum can be used. This does not need to be the lambs first drink, but should be given within its first 12 hours.
This can be done with a syringe, or bottle, but care should be used to make sure if syringing the colostrum into the lamb that it is not done to fast or there is a risk of some going into the lambs lungs.
Grafting the lamb to another ewe is generally the best option, although not always easy. If another ewe has lost her lambs in the previous 24 hours she may accept a new one, or if she only had a single and has enough milk to raise two, you may also try her out, assuming her lamb is not too much bigger than the orphan. Grafting is tricky and the ewe should be watched closely for the first week to ensure she is allowing the new lamb to drink fully. Most ewes will push strange lambs away, so grafting is not often done.
Lambs need roughly 5 oz of milk per pound of weight every day. Figure out how much this would be then break this down according to how many feeds per day your lamb will need. Assuming it is newborn it will need to be fed every 2 hours in the day for the first day, and every 3 – 4 hours at night. After the first 24 hours your lamb will be fine at night for 8 hours, and should be fed every 3 – 4 hours throughout the day for the first week.
One of the easiest ways of feeding lambs is with a pop bottle and nipple specially made for pop bottles. In most cases you can fill a 750 ml bottle and let the lamb drink as much as it wants. There is little risk of them drinking too much, however the concern is if they do not drink enough.
The formula itself should be a lamb formula, purchased from a livestock feed store, it can be made with warm tap water, test on your wrist to be sure it is not too hot.
After day three the lamb should be offered hay or lamb kibble. When introducing new things do so in limited amounts so you do not create tummy problems. If the lamb is not showing any interest in eating you may put a pinch of food in its mouth to let it see how it tastes. If you have other lambs that it can be with it may learn from them, however an orphaned lamb should not be out with the rest of the sheep as it may get left behind if sleeping and the others move away.
If the lamb has a living mother, but one that cannot, or will not, feed it, it will still bond with that ewe and unless she is physically mean to it the lamb should be kept with its mother and offered the feedings at regular intervals.
After the lamb is a week old feedings can be every 5 – 6 hours, and it should have a small bucket of water for drinking. By the time it is four weeks of age feedings can be cut down to twice a day, and once a day by the time it is eight weeks of age, eventually eliminated altogether according to its growth rate and eating habits.
Most people find bringing the lamb into their home for the first night is the easiest thing, and some will keep it in their home, in a dog pen, for the first week. The lamb should not be out with the other sheep unless they have a barn for shelter, particularly at night.
Orphaned lambs are often called "bummer" lambs.
Care that the lamb be kept warm is very important, care for twin lambs is harder work but at least the pair will cuddle at night and keep each other warm in a colder barn.
Every bag of milk replacement formula is different, always follow proper mixing instructions as on the bag. You may note that some call for different portions of water to powder according to the age of the lamb.
If any problems are noted a veterinarian should be called.
Signs of a lamb not getting enough to drink are if it stands hunched.
If a person is unable to care for an orphaned lamb they may trying contacting a 4H group as sometimes children are looking for project lambs.
The lamb will bond with you so you must also make sure it has time with other sheep so that it realizes it is a sheep.
Good luck with your orphaned lambs, hopefully you will not have too many of them!