Training big dogs

Large breeds remember that they used to hunt.  They can be trained for some tasks but for hunting
they are mostly either really good at it or not.  There are large dogs that can protect your herd and
for this you need breeding skills.  Some will forget and hunt the predator while others will not leave the
herd to drive off the predator.  It is said that molossers can be trained to pin a wild sow while the
farmer collects its litter.  The sow then follows the farmer back to the barn.  These are some of the
most mild mannered dogs you will ever meet and the idea that one can face down a sow with litter
strains my credulity.  Again, the good farmer had to be a master breeder. 
Today we confront the need for dogs that tolerate city life.  Large dogs can be adapted but I believe that
sight hounds are least likely to fit this need.  Rescue greyhounds work well because they have been run
enough for a lifetime the rest should be kept on a farm and trained to guard the chickens.
.....