Cosmo-calf at UC Davis

[aj]

He is supposed to sire 75% male calves. KNABE........explain this. The 25% of calves that were supposed to be males will grow and take on male characteristics. So..........will they have lady parts?

 

[shortybreeder]

He is supposed to sire 75% male calves. KNABE........explain this. The 25% of calves that were supposed to be males will grow and take on male characteristics. So..........will they have lady parts?

All fetuses start out as female. The Y chromosome causes a chain reaction that adds male characteristics in utero. They inserted a gene, SRY, onto a different chromosome which will also kickstart that chain reaction. It will be transferred to 50% of the calves, independent of whether they are male or female.
50% of the calves will be genetically male, so theoretically the SRY gene will have no impact on them.
25% of the calves will be genetically female, without the SRY gene, and will therefore be female.
25% of the calves will be genetically female, with the SRY gene, and will therefore appear male.

Theoretically, they won't resemble a heifer any more than you resemble a woman because the chain reaction should be identical to what happens with the Y chromosome. Time will tell if this is true though

 

[knabe]

https://www.ucdavis.edu/news/meet-cosmo-bull-calf-designed-produce-75-male-offspring/#:~:text=75%25%20Male%20Offspring-,Meet%20Cosmo%2C%20a%20Bull%20Calf%20Designed%20to%20Produce%2075%25%20Male,to%20Insert%20Sex%2DDetermining%20Gene&text=Scientists%20at%20the%20University%20of,ll%20produce%20more%20male%20offspring.


https://www.wired.com/story/a-crispr-calf-is-born-its-definitely-a-boy/


i indirectly know the people doing this.

 

[knabe]

https://www.nature.com/news/2006/061009/full/061009-14.html

 

[aj]

Just seems like so many questions. Is this something that bull producers will have to do to be viable? Could a breed get in to this on a ground floor level and have an advantage?

 

[knabe]

i don't think AI will be replaced in dairy, so sexed semen, whose price has come down is probably the answer.


the concept of the cosmo calf seems largely academic and concept proving.