I have a 3-week-old heifer calf born 2 to 4 weeks premature. She did not weigh more than 30 pounds at birth. She has been unable to get any milk from her mom, although we do think she received some colostrum. We have been bottle feeding her twice a day — 4 pints at each feeding at this point. She finally seems to be putting on some weight. What advice do you have going forward?
The biggest problems you may face going forward would most likely be respiratory disease or scours. Both are tied to a compromised immune system. If she was premature, her immune system just may not be ready for prime time yet.
You mentioned you believe she received colostrum from her dam. That does not mean she got enough, and without it, her passive immunity (this protects her until her immune system is fully functional) may well be below optimal levels. The passive immunity function is something your veterinarian can check with a simple blood test. If it is inadequate, and you want to give her the best start possible, a blood or plasma transfusion from her dam or another mature cow could benefit her greatly.
That said, this may all amount to more than you want to invest in her. It may not even be needed if she does not get sick. But if she does get sick, call your veterinarian immediately. It will be important to treat her early and correctly.
Also, be sure your sanitation is very good. Clean everything well–including her environment. If she is inside, make sure you have adequate airflow. Restrict access from visitors who might bring diseases from other animals or farms. Always be sure to use the best milk replacer, and mix and feed it correctly. Provide high-quality hay and/or grazing, and a good calf-starter grain ration. And don’t forget that sunlight is very good for these animals.