Emaciated Dog Found on 'Death's Doorstep' in Worst Condition Shelter Has Seen in 21 Years Is Now in Recovery (Exclusive)

• In January, Seamus arrived at North Shore Animal League America emaciated and covered in open wounds

• Veterinarians determined the 22-lb. dog was likely "abandoned and starved" before his rescue

• Seamus is now recovering in a foster home and has already gained 9 pounds

Seamus arrived at North Shore Animal League America in January in "dire condition," but even under extreme physical stress, the dog proved he was a fighter and a lover.

"He was still happy to be in the company of people. He was still wagging his tail and seeking affection," Dr. Gerard Lahenet, D.V.M., a supervising veterinarian with Animal League America, tells PEOPLE.

Before arriving at Animal League America, the emaciated black dog turned up at Manhattan Animal Care & Control in New York City weighing just 22 pounds, half of his suggested weight of 45 pounds.

He "was in dire condition and in need of full-time medical care. Our team traveled to N.Y.C. to transfer Seamus to us for ongoing care and eventual adoption," Dr. Laheny adds.

Once at Animal League America, located in Port Washington, N.Y., Seamus received a complete exam from the animal rescue organization's veterinarians.

"I've been here 21 years, and I don't think I've ever seen a dog with this poor of a body condition. He was likely on death's doorstep." Dr. Laheny says, adding, "We were looking for underlying medical problems but didn't find anything, so drew the conclusion he was abandoned and starved."

Related: 3 Abandoned Puppies Found in Dumpster 'Had No Chance.' Now, the 'Little Fighters' Are Healing at a Rescue

The shock of seeing Seamus' thin frame covered in open wounds profoundly impacted Animal League America's employees.

"When I first saw him, it was heartbreaking. He could barely move. It was so sad. I was feeling angry and upset. How can people do this to a dog like him? How did it get this bad?" says Deana Merino, L.V.T., Animal League America's shelter medical director.

Despite his sorry state, Seamus remained trusting, friendly, and optimistic, using his small amount of stored strength to wiggle closer to his caretakers for affection.

"It's very emotional to see an animal treated so poorly, yet they're still nice and affectionate. They don't hold anything against people," Dr. Laheny says.

Seamus's loving demeanor won over Merino, who decided to take the pooch home as a foster pet to help him recover in peace.

"With my medical background, I know I can help him gain weight the right way, feed him well, and offer him the love and care he deserves," Merino says of the decision, adding that fostering helps pets escape the loud, often stressful shelter environment, and get comfortable living in a home.

Since moving in with Merino, Seamus has been focused on his recovery, which includes a well-balanced diet made of easily digestible, high-protein foods. Over the past few weeks, Seamus has gained weight safely and has overcome the anemia he developed due to his malnourishment.

"We're also working on improving his overall condition, including building his muscle tone. Our goal is to get him healthy enough to be neutered," Dr. Laheny explains.

Related: Family Proves 'Rescue is Forever' After Newly Adopted Dog Develops Health Issues. And Then the Pup Pays it Forward (Exclusive)

Once Seamus is strong and healthy enough to undergo his neuter surgery, he will only be a few steps away from being available for adoption.

The veterinarian says Seamus will likely undergo the procedure in 3 to 4 weeks and has gained 9 pounds since coming under Animal League America's care. Merino notes that she has seen Seamus gaining excitement and vitality as well.

"Recently, my dogs were running outside, and Seamus wanted to run with them. He couldn't, but you could see his will was there. In time, he'll be strong enough to join in," she says.

According to Merino, Seamus is sure to make his future forever family happy. The dog loves cuddling and being near the people he cares about. Plus, he gets along great with other dogs and respects cats.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer​​, from celebrity news to compelling human interest stories. 

"Despite whatever horror he went through, he is such a friendly and sweet dog. He keeps pushing himself as much as he can," Merino says.

For more information about Seamus and how to donate to help his recovery, visit www.animalleague.org. Also, keep an eye out for North Shore Animal League America during the Great American Rescue Bowl, an adorable canine football event featuring adoptable shelter pets airing on Feb 9. at 12 p.m. on the Great American Family channel.

Read the original article on People