The assumption being that if the cows withstood 10 years of culling, and
attrition from natural causes, then such cows may be genetically superior.
--
Kindest regards,
========================
F. W. Owen
Luck is more of a factor than you may think. A 6 year old cow that might
have made 10 years does the splits on some ice. Has nothing to do with her
genetic traits, just bad luck cuts her career short. I experienced a very
low SCC, which was most likely the result of culling cows with weak immune
systems since the herd was started in 1883. After a century of dairying,
you'd end up with a herd that features strong immune systems. But luck is
still an element. Heifer gets pregnant with twins, has a rough calving and
bingo, an otherwise 10 year old potential cow is toast. There are many,
many things that can go wrong, that have nothing to do with genetics, the
farmer's management skills, sometimes stuff just happens.
And then there's the matter of increased odds. A young cow can handle and
bounce back from a certain amount of bad luck. So we come to one of those
times of low milk prices, the herd is at the top end of the population
numbers one can handle, so which cows get culled? Often the older ones
because the odds of old age and complications are increasing.
Now, to a point I'd sell a young bred heifer if the market was commanding
good money, and keep the older cow to a point. But there comes a time
when Bret Farve is an old player and can't do the performance done in so
many years past.
Dave G.
