Bottle fed fawns sick

This is our 4th year bottle feeding fawns and we have a new barn this year. We have pulled 5 doe fawns and we are bottle feeding with Land O Lakes Replacer. We have lost 3 of the 5 suddenly. We have been adding pumpkin to the formula from the start. The fawns back off the bottle, start having diarrhea and are dead within 48 hours. We have tried adding yogurt to bottles, giving them dirt, jumpstart/probiotic paste, Bounce/Formula 911 , even pepto bismol, and nothing helps. We just can't get ahead of it. The last 2 fawns living are eating well and having regular stools. They are 4 weeks old and eating 8-10 oz 4 times a day.

This morning I have another one starting with scours. I have given it 1/2 cc Baytril 100, 3 cc pepto bismal and jumpstart probiotic paste. I am giving it bounce in between feedings.

I am wondering if it has something to do with new barn? Or formula? I have never swapped formula during bottle feeding...I always stick with what we start with, but if I have another sick one I am up for any suggestions. This is very sad and disheartening to loose these fawns.

Any suggestions would be greatly appreciated.

sick fawns

Talked to our vet and he recommended taking them off formula today and give them bounce. Keep giving 1/2 cc Baytril per day until scours are gone. Start back on formula tomorrow and lower the amount of powder to water.

I have never used Red cap milk or swapped formulas mid stream. Should I mix current replacer with Red cap and slowly transition them to only red cap or just switch to red cap after day of bounce?