Undoubtedly there are as many formulas for feeding orphan deer as there are deer farmers. One formula that works well is the one used by the Western Plains Zoo at Dubbo in New South Wales.
Formula:
Full cream powdered milk at 150g/litre made up to 1 Litre with cooled boiled water.
Two egg yolks, 150ml thickened cream, 1 tablespoon of natural yogurt, 10ml Enervol.
Make sure that the yogurt is added just BEFORE mixing each feed. If it is added to a bulk mix in advance, it will curdle the whole batch of formula!
Whisk all this together, warm to body temperature and feed the fawn/calf using a standard lamb teat. Small fawns may require Kangaroo or Wombat teats.
Technique:
Fawns/calves taken from their mothers within the first 48 hours should be fed deer colostrum only for the first 24 hours of hand raising. If this is not available the next best is goat or cow colostrum. They require at least 100 to 200ml of colostrum in total depending on bodyweight.
In the second 24 hours feed the formula at half strength mixed with an electrolyte replacer such as Vy-Trate. In the third 24 hours feed at three quarter strength and then full strength.
If diarrhoea develops reduce to half strength for 48 hours and gradually return to the full strength mixture. The orphan must have a routine. Feeding volumes and times must be set and adhered to. Start with four feeds per day for the first seven days - eg. (9am, 2pm, 6pm & 10pm) then as they can take more per feed cut down to three feeds daily.
Don't make a rod for your own back! Keep them outside when warm and in a shed or yard at night away from foxes. They can quickly become pets and when older the hand raised buck/stag is very dangerous during the rut and the doe/hind will be difficult to mate.
The volume of colostrum and formula depends on bodyweight. They require 15-20% for growth. Thus a 10Kg Red Deer calf will need up to two Litre per day. The volume of formula need not be increased as the orphan begins to eat solids provided it is gaining weight. Monitor the weight gain weekly.
Teats and bottles MUST be washed after each feed in a chlorine based disinfectant such as Domestos. After each feed wipe gently around the anus with a disposable nappy-liner moistened with baby oil. This stimulates the fawn/calf to defecate. In addition clean the coat and mouth to prevent a build-up of stale milk which will cause diarrhoea and thrush.
This all sounds relatively easy until the stubborn calf or fawn is encountered who refuses to accept the teat. This youngster requires very firm persistence. The most important aspect is to force the teat into the mouth to stimulate suckling and to get it used to the taste of milk. Greater perseverance is required if an older calf or fawn is to be hand raised, since this animal will have developed a strong bond with it’s mother and the substitute mother (you) will be foreign to it.
WARNING!
Do NOT make pets of MALE deer since they are potentially LETHAL during the RUT. If you intend to keep a male deer as a pet CASTRATE him by 6 to 8 weeks of age. The disadvantage of this is that he will never grow antlers.