Lotus wrote in message
...
"Jim Webster" wrote in message
news:aurghf$eb6

But just to explain in short sentences a mineralised feed block may
well
contain protein which could well be part of the whole BSE/MBM
problem.

But suckler herds had lower incidence of BSE than dairy herds, not
more.

exactly.
Remember where beef cows come from.
The vast majority of UK beef cows are daughters of dairy cows and are
born and often reared on dairy farms. In this we differ entirely from
the USA.
Therefore most beef cows, as calves, will have drunk milk replacer or
eaten propriatory calf rations. A high proportion of beef cows were
reared under conditions almost entirely the same as replacement dairy
heifers.
The difference in rates of BSE between beef and dairy cattle is easily
enough explained by this proportion. This is especially true as if you
look at the map of BSE incidence in the UK, beef herd replacement
animals will be (by chance) drawn from the areas where BSE incidence is
lower in the local dairy herd.

Remember that a lot of farmers who had BSE in their dairy herds did not
feed a compound feed to adult cattle and certainly never bought MBM.
They also never used a warble dressing on animals who went down with
BSE.
But virtually all would have used a commercial ration on calves, because
young animals need more careful feeding and tend to be looked after
better, as they cannot balance out their feed with grazing. It is
probable that a lot of milk powder feeds contained MBM, as a calf is
built to eat animal protein, and it is undoubtedly probable that a lot
of the calf rearing rations contained high quality animal protein
(because, again, calves to need high quality animal protein and respond
to it.)

So you do not need to worry too much about the diets of adult cattle and
BSE. After all many of the animals that went down with BSE had never
been exposed to MBM as adult cattle and they had obviously never been
exposed to Organophosphates.

Everything is more reasonably explained by the animal being infected in
the first twelve weeks of life.

--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'