[Lingo] 黒犬 vs. 黒い犬

[steve <sjs@example.com>]

Hi all.

I'm working my way through a Japanes3 3rd grade reader.  It has a short 
story about "a small black dog and his small blue coat."  I plugged a 
sentence containing 黒犬 into google translate and was surprised to see it 
pronounced 「こっけん」as though it was 熟語.  Likewise for 白犬(はっけん).

This seems wrong to me somehow, and the IME recognizes くろいぬ as 黒犬 but 
has no translation for こっけん->黒犬.

I'm guessing this is a problem with written vs. spoken Japanese and that 
typically one would say 「くろいいぬ」.  And I'm guessing if one were reading 
the story aloud one would read 黒犬 as くろいいぬ. Is this correct?

Also I think there is a larger pattern here but I don't quite know how 
to put my question.  Any comments??

Thank you
Steve Smith