Benevolent parasite story

Hi folks,

You know what they say.... "memory" is the second thing to go....

.... I just don't recall what the first one was... *sigh*


And so it is trying to recall the title of a science fiction book I
read years ago... and I'm hoping someone may recall the title for me.

The plot line consists of describing how a sentient parasitic being
drifted through space until he landed on earth while in his small
'seed' form.  He waited dormant for a potential host,... was eaten by a
cow while it was grazing, recognized that this 'host', although warm
blooded, was not sufficient to be a true host.  He remained dormant
within the cow until the animal was slaughtered and ended up in a
package of hamburger meat, which was ultimately made into hamburgers
and eaten by a human.  The rest of the story deals with the parasitic
being 'adventures' within this human and trying to communicate with
him.

Does this ring a bell with any of you readers of science fiction??

Thanks