General Care


Complete, Compassionate Care

Our team is dedicated to your pet’s health!

Heartworm Disease

Heartworm disease has been found across the US, including Colorado. All dogs are at risk for this disease. Fortunately, there is a once-a-month pill to help prevent heartworm infection. Mosquitos carry this disease and transfer it between dogs. Your dog should be tested yearly for heartworm and kept on preventive medication year-round.

We all know that Colorado has mosquitos. In fact, we are the #1 state for West Nile Virus infections from mosquito bites.

In addition to the existing mosquito problems in Colorado, relocation of Hurricane Rita and Katrina dogs has had a dramatic effect on the number of dogs in our area that have heartworm disease and intestinal parasites. It has been estimated that about 85% of these evacuated dogs are/were positive for heartworm disease.

Question: My dog stays mostly inside. Why does he need heartworm preventative?

Answer: Even if your dog only ventures outside for backyard bathroom duties, there is still an opportunity for a host mosquito to feed on your dog and transfer the heartworm into their bloodstream. Mosquitos may also enter your house during the summer and infect your dog. “Inside” dogs are not safe from heartworm.

Question: Mosquitos are only out in the summer. Why are you recommending heartworm preventive to be given year-round?

Answer: Here in Colorado, our winters are getting shorter and spring seems to start earlier every year. Mosquitos are out for longer periods of time. Our heartworm preventives, Interceptor and Heartguard Plus, also protect against intestinal parasites like hookworms, roundworms, and whipworms.

These parasites are found year round and are of particular concern because they are Zoonotic (humans can contract them from pets). People at greatest risk are pregnant women, children, seniors, and people who are immuno-suppressed. This is why Interceptor and Heartguard Plus are still beneficial to our dogs in the winter months, when mosquitos are not present.

Question: Why should my dog be tested for heartworm every year if he is on preventive year-round?

Answer: No medication is 100% effective against heartworms, although we feel Interceptor and Heartguard Plus are the best available. Also, your dog may spit out or vomit up the preventive without your knowledge.

With today’s busy lifestyles, many people forget to give a pill, or give it late, which can affect its efficacy.

It is best to test for heartworms before continuing the preventive due to health risks if your dog has adult heartworms.

Life Cycle

Heartworm Life Cycle

A mosquito feeds on an infected dog and takes up the immature worm in its meal.
The immature worm undergoes some maturity in the mosquito.
The mosquito feeds on another dog and inoculates the host dog with the heartworm.
The heartworm continues to mature in the dog and takes about 6 months to travel to the heart.
The adult heartworm remains in the right side of the heart, where it causes heart disease.
If additional infections occur and multiple adults reside in the heart, offspring can be produced and circulate in the blood stream.

Signs of heartworm disease

Since heartworm infects the heart, many of the signs associated with this condition are related to the heart.

It can take many months to develop symptoms, but a dog can start coughing within four months of infection. Weight loss and lethargy are also common signs.

Raintree Animal Hospital offers a test for heartworms that consists of a quick blood draw and provides results by the next day. Once we know your dog is heartworm free, he can stay that way with monthly preventive treatment. Raintree Animal Hospital uses Interceptor and Heartguard Plus monthly preventives. It also protects against intestinal parasites. Call us today at (970) 482-1987 to schedule a heartworm test and to purchase a preventive. We recommend prevention year-round.

Laboratory Tests

Intestinal Parasite Screening: Performed yearly to detect intestinal parasites present in your pet’s feces that can affect both you and your pet.

Heartworm Prevention and Testing: Yearly testing and use of preventive medications for dogs.

Blood work and urinalysis: We recommend that this lab work be performed every year as your pet ages. Routine testing helps to detect problems not evident on physical exam.

  • The blood work includes a complete blood count, which looks for anemia, infection, inflammation, and evidence of cancer.
  • The blood chemistry test, which will be performed, may diagnose problems like diabetes, kidney failure, liver disease, and cancer.
  • A thyroid test is also performed to detect hypothyroidism (under-active thyroid) in dogs and hyperthyroidism (overactive thyroid) in cats.
  • The urinalysis helps evaluate kidney function, evidence of diabetes, infection, and urinary stones/crystals.

Health Tips

Summer Camping Tips

A lot of Coloradoans enjoy the great scenery our beautiful state has to offer and they like to share the experience with their pets.

Here are some tips for camping with your pet:

  • Have your dog microchipped as a form of positive I.D. in case he loses his collar.
  • Make sure you pack fresh water and a dish for your pet. Streams and water ways in Colorado contain parasites, such as giardia, that can cause your pet to get sick.
  • Protect your dog against ticks and mosquitos—use FRONTLINE Plus.
  • Tie on a glow stick to your pet’s collar to make him visible at night and easy to track.
  • Bring plastic baggies to dispose of waste.
  • Keep your pet on the trails to respect wildlife.
  • Some areas do not permit pets. Call ahead to make sure your dog is welcome.

Fleas, ticks, and your pet

With warmer weather, the pet owner will be confronting the problem of fleas and ticks. For dogs we recommend FRONTLINE Plus — a new product on the market for dogs. FRONTLINE Plus is ideal for use on puppies 8 weeks of age or older. Not only does FRONTINE Plus kill up to 100% of adult fleas on your pet within 24 hours, it also contains a special ingredient that kills flea eggs and larvae to keep ALL stages of fleas from developing and bothering your pet and your family.

FRONTLINE Plus completely breaks the flea life cycle by effectively stopping the development of new fleas. Additionally, FRONTLINE Plus kills all stages of 4 major ticks, including the one that may carry Lyme disease.

FRONTLINE Plus is administered according to the weight of your dog in four dosing sizes: up to 22 lbs., 23–44 lbs., 45–88 lbs., and 89–132 lbs. FRONTLINE Plus is available in three-dose packages. For our feline patients, we carry Revolution flea control. Revolution kills 98% of fleas within 12 hours and continues to work for up to one month per application. It also breaks the flea life cycle by killing flea larvae.

Revolution can be used on kittens 8 weeks old. It is safe for use on pregnant and nursing cats. Revolution also controls and treats ticks, ear mites, sarcoptic mange, hookworms, and roundworms, as well as preventing heartworm disease caused by Dirofilaria immitis. Revolution is water-resistant, so it kills fleas even after shampooing and exposure to rain. Revolution is applied to the back of the neck on cats.


Nutrition plays a key role in both the maintenance of good health and managing disease. Our staff at Raintree Animal Hospital can help you choose the correct diet to maintain your pet’s optimal health and make diet recommendations for the management of medical conditions.

Dietary therapy can improve and delay the progress of such diseases as obesity, periodontal disease, inflammatory bowel disorders, colitis, pancreatitis, kidney, and liver disease. We proudly offer the optimal nutrition and medical benefit of Hill’s and Iam’s Prescription Diets.

Choosing the correct diet is not limited to dogs and cats. Diet is the foundation of ensuring optimal longevity and health in animals such as ferrets, rats, mice, guinea pigs, and birds.

Raintree carries a full line of Oxbow products to ensure maximal nutritional benefits for small mammals. Oxbow is a small, family-owned, quality-controlled business that specializes in fortified feeds and treats for exotic herbivores such as bunnies, guinea pigs, rats, and chinchillas. The nutritional value of Oxbow Diets helps add to the health and longevity of your exotic pet.

We also keep a fresh variety of Harrison’s Premium bird diets for your feathered friends.

Harrison’s Bird Diet was developed by a veterinarian who specializes in avian medicine. Pre-and post-processing analyses are performed to determine and monitor the nutrient content in each batch of food. Harrison’s quality controls ensure that their products are “safe for human consumption” so feel free to try it yourself.

Harrison’s Bird diets are certified organic and do not contain chemicals, insecticides, herbicides or fungicides, preservatives, artificial colors, double-dosed vitamins, bacteria, or mycotoxins.

Malnutrition is the cause of 90% of health problems and is the leading cause of death in pet birds.

A diet of seeds, millet, sunflower, etc. (even if they are fortified) are packed with fat and are lacking over 32 essential nutrients for birds.

Our staff will gladly assist you in finding the right diet for your bird and help you with the process of converting them onto a better diet.

Trust, Convenience, and Value

At Raintree Animal Hospital, we respect your bond with your pet, and we are dedicated to meeting your needs and concerns while providing the highest quality care for your pet—from birth through their senior years.


Fort Collins
Phone: (970) 482-1987

Fax: (970) 482-6775

Phone: (970) 486-1807
(970) 225-5482


 7:30 am to 6:00 pm
Sat: 7:30 am to 12:00 pm
Sun: Closed

Boarding & Daycare
Mon-Fri: 7:30am - 6pm
Sat: 8am-6pm
Sun: 10am-6pm

Daycare Pick-up & Drop Off 
Mon-Fri: 7:30am - 5:30pm
Sat - Sun: 10am - 4pm


Fort Collins
2335 S Shields St.
Fort Collins, CO 80526
Click here for directions.

5620 E. Harmony Rd.
Timnath, CO 80547
Click here for directions.

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