>>I'm not saying that onions, garlic and chocolate have
>>not been known to cause illness or even death in
>>canines. I'm just wondering why the dogs I knew 25
>>years ago never seemed to suffer ill effects.

        I personally think there are a couple things at work here.
        I betcha 25 years ago there were dogs dying from exposure to
chocolate, onions, or garlic but folks were less likely to investigate the
cause of death and strangers 6 states and a dozen breeds away were a lot
less likely to hear about it. So now we get the word out and red flags go
up faster.
        I also think that some dogs have more tolerance than others. Garlic
is pretty common in small doses in a bunch of dog foods and dog treats. (I
also think it is more common in your average American diet than it was 25
years ago... my mom only used garlic when she made London Broil whereas my
friends and I toss some garlic in to just about anything...) A dog that is
inordinatly sensitive to garlic is unlikley to pass those genes on to the
next generation if it dies young from eating regular food. On the other
hand, more and more people have heard that chocolate is not good for dogs
and any excuse to not share my candy bar is a good one as far as I'm
concerned. So perhaps more dogs are not getting any exposure to chocolate
and dogs with a high chocolate sensitivity may well send that on down to
the next generation.
        Plus, as Elaine pointed out, more dogs are leading sedentary lives,
which may make their hearts less able to withstand the strain should they
have an adverse reaction.

        jan