Genetic heritability

[JeffNY]

When breeding cattle, especially when it comes to registered cattle the "correct" bull is selected for a particular heifer or cow. Here is a question for those who are familiar with this.

The Dam has a heifer, the heifer's sire was Bull Z. You used Bull Z to improve things in the dam, whether it is udder or frame. However when the heifer is born, you noticed a heifer similar to that of the dam, not Bull Z. Well the heifer has come into heat, and it is time to breed. So you use Bull Y, but when the heifer calves it tends to look more like what Bull Z transmits. Can this happen? Where the genetics remain in the heifer, but do not show till the heifer has a calf, and Bull Z tends to show up in the calf.


Thanks!

Jeff

[Oxankle]

Jeff;
Have you never heard the old folks say that you never see yourself as you were until you see your grandchildren?

On that score, look at the bull catalogues. The older bulls sometimes have a reliability score assigned, one that is based on hundreds of progeny. It gives you the likelihood of getting progeny that mirror the sire.

Ox

[Jennifer L.]

A lot of the time what you are trying to improve comes slowly over several generations. Using that good bull one time can't be instant.

Some traits improve faster than others, and in those cases it's because the number of genes controling the trait are fewer, or because the dam is already carrying some recessive genes that are needed. The traits that are slower to improve will be because there are more genes involved, or because the dam has no recessives already to speed things up.

Remember that by the time you have a grand daughter of a good cow that you are trying to improve, she has only 1/4 of the genes from that good cow. Everything else is coming in from the bulls' families chosen by the bull stud where that good trait you are trying to get into that heifer calf has been concentrated.

Jennifer

[caseyweiss]

Jeff,

In my experience breeding dairy cattle, some bulls are very prepotent and others are not. Same with cows. There are several bulls that I have used, namely Othello and Royalty, who make their calves cookie-cutters, they are the exact same type every single time regardless of dam. I call these bulls changers.

My grandpa says, he milked for over 50 years, that you will never have a good uddered herd if you don't start with one.

Casey