My chi, Quark has been hacking all day. He has brought up some foamy spit a couple of times, but still keeps hacking and trying to bring something up. Could this just be something he ate in the yard? Or the fact that he steals poop out of the cats litter boxes? He's on raw diet, and I've never noticed him having any problem with bones. He's constantly sniffing and licking the floor throughout the house looking for crumbs, even going so far as to lick under the refrigerator for whatever crud has accumulated there. I have another dog, and several cats so there's always fur and dust around, as well as a messy husband who drops crumbs. Could any of this be the factor or is it the trachea? He acts perfectly normal otherwise. What can I try to correct it at home...pumpkin? oil?. I have no money for vet bills right now. Thanks.