HETEROZYGOUS HOLSTEIN POLLED BULLS:
These bulls when listed by a stud and others here high predicted proofs and will produce 50% polled calves when mated to horned cows. These bulls can be selectively used in embryo transfer flushings with polled cows to create future elite polled animals. The breeding plan would be to create as many polled elite cows by breeding elite cows to listed homozygous polled bulls or listed heterozygous polled bulls to produce as many new elite polled animals as possible. Then in the next generation, mating a polled bull to a polled cow will produce 25% or better homozygous polled bulls and cows which can be proved by DNA testing. These then can be used to create the next generation. When heterozygous polled bulls are mated to high PTAM polled cows which have a CTPI higher than the PTPI listed for the bull, the offspring can be used for our future breeding sample bulls and tested using the DNA test for homozygosity. The higher the PTPI the offspring has the more likely a bull stud will want to offer samples for proofing the bull, especially if PTAP can be in the +70# range. This would say that any highly classified cow with at least a 34000M 305 day record and 1224 #Fat and 1088 # protein would be a candidate for stud sampling and yield further breed improvement. The higher numbers the better.
Numbers over 40,000 lb (18000kg) can easily be found at http://users.1st.net/asone/trackrecord.htm http://www.aipl.arsusda.gov/dynamic/elite/Eframe.htm
Other sources to start breeding to polled animals for creating a new polled line include those showing at World Expo. Indeed some of the winners at World Expo have been naturally polled. For past listing of animals shown at Expo go to http://www.world-dairy-expo.com/dcs.main.cfm and then select the breed you are interested in.
The top ranked Heterozygous Holstein Polled bull is Hickorymea OSWALD
http://abs-bs.absglobal.com/milk.asp?CodTouro=29HO10446