My lab is feeling sick the...

Question
My lab is feeling sick the past couple of days and I need to know if it
might be serious.  He is usually a hyper dog and now he just sits and
kindof watches everything he will just come up and lay his head on my lap.
He hasn't eaten very much lately and he throws up every now and again.  I
switched food recently and I don't know if that could be it.  I am not
sure if it is parvo.  He had his shots in october.  We live in Arizona and
I don't know if maybe it is a spider bite or he ate a funny plant.  I ran
my hands around him to see if maybe he had a sore spot.  But I could not
find one.  If you think you might know what it is let me know.  I would
appreciate it.  

Answer
Hi there!  Getting him to your veterinarian as soon as possible would prove to be most beneficial.  He may just be having a stomach upset, or he may have a partial intestinal blockage that will need veterinary care.  It would be unlikely to be parvo, as he has had his vaccination, and parvo causes chronic diarrhea.  Labs have a tendancy to eat things they shouldn't (my parents have a lab...and he is definately the curious one!), so anytime they do not eat much and vomit, chances are they did get into something they shouldn't have.  The change in food could cause a stomach upset, but this, again, would be diarrhea.  I would definately recommend a physical examination by your veterinarian, as if there is something lodged in his intestinal track, it needs to be treated ASAP.
I hope this has been helpful and give that labby boy some kisses for me!
Hilary