The rule of thumb is 1 cc per ounce of body weight for total handfeeding. 1 cc equal 1 ml and there are 5 ml in a teaspoon so she should be eating about 1/4 of a teaspoon 8 times a day (every 3 hours), if she isn't getting anything from Mom. She can only get and receive immunity from Mom during the first 24 to 48 hours so it is important that she nurses from Mom also at this time, if at all possible.
I'm just guessing here, because it will really depend on how much milk Mom is producing and how the pups' weight gain is going. I think I would start out supplementing no more than 3 times a day. If one is losing weight or lagging behind the others than I would increase that particular pups feedings.
You said the littlest pup is having trouble latching on - does any milk come out of her nose (indication of a cleft palate) while feeding? |