4th year vet students in the Teaching Hospital are coping with a stream of animal emergencies. Casey, a black lab, appears to be healthy but an ultrasound reveals a tumor the size of a cantaloupe that must be removed. Casey's owner, Shaun Young, is distraught as the vets prepare for surgery. At the same time, a muskox arrives from a nearby ranch needing dental surgery and a stray cat hit by a car comes into the clinic in critical condition. Meanwhile, vet student Tammi Orban and her classmates learn the fine art of rectal palpation on a herd of cows.
A 23 year old former race horse named Ketepwa is wasting away. She has severed a large part of her tongue and is losing weight rapidly. Since it's dangerous to put a horse this old under general anesthetic, Surgical Resident Dr. Ryan Shoemaker must cut off part of Ketepwa's tongue while the horse is standing and only partially sedated. Elsewhere in the clinic, the surgical team performs an innovative new procedure on a Yorkshire Terrier with breathing problems. Dr. Dennilyn Parker makes the rounds with a new group of students in the exotic pets rotation. Two freshmen get to try their hands at cow handling, while the vet team deals with a puppy that has swallowed its owners underwear.
Nico the Chihauhua has a severe problem with aggression and his owner Tobi Yandt suspects that her other Chihuahua, Noelle, has dental problems. In the Small Animal Clinic, vet student Jackie Pierce performs her first dental surgery, removing most of Noelle's rotten teeth while vet student Diane Cruickshank takes on Nico's psycho behavior. Two severely dehydrated calves are brought in and the vets struggle to pull them back from the brink of death. A routine examination on some pet ferrets turns up a surprise and vet student Heather Connelly performs a spay operation on a large juvenile dog, which proves to be a bigger challenge than she anticipated.
Merlin is a hearing service dog and the long-time companion of his deaf owner, Helen Tonita. Helen has brought Merlin to the clinic because she suspects his eyesight is failing. Vet student Lana Bissett performs an initial assessment that points to cataracts as the problem. But veterinary ophthalmologist Dr.Grahn discovers that Merlin is permanently blind, which has a dramatic emotional impact on the poodle's owner. Now Helen will have to be the dog's eyes, while Merlin will be her ears. In the Large Animal Clinic, a vet student must perform her first emergency caesarean section on a cow in distress. An orphaned lamb with three broken legs becomes a ward of the College and a concerned owner must raise money to biopsy the ugly bumps that have appeared on her hairless albino pet rat.
Murray Popplewell notices his Arabian foal had swollen joints in her hind legs and brings her to the Teaching Hospital. Vet student Ulrike Helvoight assumes that the foal's joints can be drained and it is treated with antibiotics. But an antibody test reveals that the young horse is much more seriously ill than initially suspected. The owner is now faced with a difficult decision. In the Small Animal Clinic, a surgical resident repairs torn ligaments on a young Rottweiler. A lynx arrives from the zoo and must be subdued with an anesthetic blow dart before its vasectomy surgery. Lambertus, the orphaned lamb with three broken legs, makes a visit to a pre-school.
Riza, a one-year-old German Shepard, has been rushed to the Teaching Hospital by his worried owner. The dog is lethargic, coughing, and having difficulty breathing. Small Animal Intern Dr. Sharon Finster puts the dog on oxygen, performs a blood gas test and takes samples. The pathology lab confirms the presence of Blastomicosis, a deadly fungal disease, and Riza is put on medications. Meanwhile, a juvenile alpaca comes in for cataract surgery and sees its mother for the very first time; a champion pulling horse needs surgery on an injured foot; and Lambertus, the orphan lamb, has his casts replaced.
Sonic is in serious trouble and severe pain from colic, one of the major causes of death among horses. Rushed to the Large Animal Clinic by his owner Marion Kopeck, he is quickly readied for abdominal surgery. Faculty Surgeon Dr. Jeremy Bailey leads the team through this major operation, which requires the removal of some 20 feet of dead intestine from the horse. Everyone anxiously watches and waits as the horse recovers during the critical period following surgery. In the Small Animal Clinic, a total hip replacement surgery is performed on one dog while porcupine quills are removed from another's nose. Lambertus, the orphan lamb, is adopted by a student and goes home with her to a farm.
Fantasia is a two-week-old llama that has a broken hind leg. Her hopeful owners have brought her to the clinic and the decision is made to go ahead with the surgery - a long complex procedure that will realign the femur so that Fantasia can use her leg again. After some initial problems putting a breathing tube down the llama's long trachea, the surgical team must cut the leg bone and realign it using a jig. Elsewhere, a thirsty cat that is losing weight is diagnosed with diabetes, an iguana has unusual bumps on his face, and a dog with swollen eyes appears to be suffering from an allergic reaction.
Ultrasound tests reveal a young Pug named Mei-Ling is suffering from a congenital condition that could take her life because vessels that should bring blood to the liver are shunting it away. As a result, Mei-Ling's blood is not being filtered of deadly toxins. Surgeons Dr. Kathy Linn and Dr. Lori MacDougall perform a complicated surgery to re-route Mei-Ling's blood back through her liver. Elsewhere, a chinchilla needs dental work and a young calf needs surgery to fix a hernia. Out on field service, the vet team tends to a horse that has impaled itself in the chest.
Pam the dairy cow is in a lot of pain, enough to kill her. One of her four stomachs twisted out of position when she recently gave birth to her calf. The vet team needs to surgically deflate one of Pam's stomachs in order to access the wayward one and reposition it. The case is both challenging and nerve-wracking for student Evan Orchard; this is the first time he's ever performed this surgery. Down the hall, a prized foal arrives with a wounded knee that won't heal; an old dog might be suffering from heart failure; a cat's fighting ways have left it with a painful infection; and a bull has gotten a little too close to a porcupine.
When Quake was just a colt, another horse kicked him in the face, crushing the bridge of his nose. Initially the injury wasn't a problem but now that Quake's an adult, he's having trouble breathing and tires easily. Quake needs a nose job and that falls to Dr. Peter Fretz who must rebuild the horse's nose, using metal plates and wire. Meanwhile in the Small Animal Clinic, state-of-the-art cataract surgery saves a young dog's vision, a tiny Shiatsu has swallowed a sewing needle and the vets suspect that a young golden eagle is infected with West Nile virus.
Vet student Jennifer Klaus adopted an abandoned pet iguana named Dante. In her radiology rotation, she was allowed to take an x-ray of her pet and discovered that Dante had swallowed a screw. An endoscope is used on the iguana in an effort to find the screw in his stomach or intestinal track, to no avail. Finally, Dante is anesthetized for surgery and the screw is delicately removed. Meanwhile, vet students assist with a sterile birthing of piglets that keeps the newborns disease-free, check on a pregnant horse and meet a cowboy who hopes they can help his constipated buffalo.
Bob Maskell is worried sick about his dog Bonnie, a 13-year-old Skye Terrier, that has recently started having seizures. As the vet team runs diagnostic tests on the dog, it's clear she's suffering from a neurological problem. But it's not until Bonnie undergoes MRI (magnetic resonance imaging) that the sad truth is revealed: the old dog has a brain tumor and the vet team must determine if it's operable or not. Elsewhere in the small animal clinic, a miniature horse has a pill lodged in its throat, a root canal is performed on a ferret with a broken tooth and the students give vaccinations to a throng of dogs and cats.