JURUPA VALLEY (CBSLA) – An 8-month-old German Shepherd is getting the nourishment he needs after someone left him clinging to life in the overnight drop box at the Riverside County Animal Shelter.

“You can see just how skinny he is,” said shelter spokesperson John Welsh.

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The bones are visible on his bottom and ribs, and he’s just half the weight he should be for his age and size.

“Hovering right about 20, just shy of 28,” Welsh said.

Those nearly 28 pounds include more than 4 pounds he has gained at the shelter since he has received fluids through an IV and scarfed down some much-needed food.

“When you see an animal in this kind of condition, you wanna throw the stethoscope against the wall because it’s like who does this?” Welsh said.

That’s the question all the caretakers at the shelter want answered.

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Right now, they’re looking through their camera system to see if they can spot whoever dropped him off, and get to the bottom of what happened to him.

Welsh said based on his sweet, trusting demeanor and leash etiquette that, at one point, he had a well-intentioned owner.

“Perhaps it got out of the owner’s property and perhaps it’s been fending for itself,” Welsh said.

But with indentations around his snout, Welsh believes someone may have left him muzzled too tight for a very long time or possibly secured his mouth shut.

“We’re open to people calling and saying, ‘Hey, I know that dog and I know where that dog lived,” Welsh said.

They want to make sure the next place he lives, he’ll be in good hands.

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The shelter said the pup is expected to make a full recovery.