525,000 Dead Calves

     On March 23, 2015 I posted a blog entry entitled “Inbreeding” in which I pointed out 49% of today’s Holstein genetic lineage go back to a famous bull known as Chief (Pawnee Farm Arlinda Chief).  I commented one of the pitfalls of inbreeding was  diminished reproductive efficiency.

     Now, a recent article in Progressive Dairyman reports genomic research has found a genetic defect in Chief and some of his sons.  This defect has been linked to decreased conception rates and increased stillbirths. It is estimated to be the cause of 525,000 stillborn calf deaths worldwide.  One of the researchers opined the reason it took so many decades to find the problem was because most abortions are blamed on the cow rather than the bull. 

     The PD article states Chief is responsible for 14 percent of the current Holstein genome in the U.S.  The difference between this figure and the 49% quoted above is due to differences in the time period and the degree of relationship sampled.

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     Chief’s offspring include more than 16,000 daughters, 500,000 granddaughters, and 2 million great-granddaughters, as well as several sons that became popular sires. Mark, one of Chief’s sons is pictured above.

     This discovery confirms my belief in a more restrained approach to meddling with genetics.  Chief’s problem arose from the relatively benign selective breeding techniques practiced for centuries.  I fear the current craze to indiscriminately mix genetics from different species will someday come back to bite us in the butt. 

     Hopefully, one day soon, we will collectively experience a moment of lucidity, slap ourselves on the forehead and say; “Maybe we ought to be more careful fooling around with Mother Nature”. . . .  but I’m not holding my breath while waiting for it to happen. 

Learn more about Chief at:  http://www.progressivedairy.com/topics/a-i-breeding/genetic-mutation-from-one-bull-caused-loss-of-500-000-calves

rjhdvm@gmail.com