The question of how nipple drinkers function when subjected to freezing temperatures has often been asked. Since freezing temperatures are not a part of the efficient poultry industry no manufacturer of nipple drinkers or commercial operation has undertaken research into this matter. So I have done some informal experimentation myself. I installed five push-in type nipples in the bottom of a 2.5 gallon plastic pail, filled it with tap water (12" deep) and froze it solid in a deep freezer that seemed to average around -3 degrees F. I left the bucket with nipples and water in the freezer for about 36 hours. I then removed the whole deal from the freezer and allowed the water to thaw at room temperature (took about eight hours) and stand another day or more and observed no nipple damage, leakage of loss of function. This procedure was replicated three times refreezing the same nipples over and over. No loss of function or damage was observed at any time. After the third and last thawing I conducted what is known as the Lott Test. That is the method used to determine the water outflow of nipples in the field. I found no significant variance in the outflow of the nipples expressed as optimum by the manufacturer. It might be concluded from this informal experiment that freezing does not damage the push-in type nipples many here are familiar with. The minor differences between the push-in type nipple and the threaded nipple lead me to believe that the same result could be expected if similar tests were conducted with the threaded variation. I believe that the most likely damage to occur from freezing a nipple drinker system would occur in the PVC piping.