• Digestive Health

    A horse’s digestive system begins with the mouth, ends with the anus and incorporates all the organs in between that are involved in consuming and processing food. Its purpose is fourfold: to digest food, absorb nutrients, move food through the digestive tract and eliminate waste products in the form

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  • Cryptochidism

    Cryptorchidism is a condition in which one or both testicles fail to descend into the scrotum. This is the most common problem affecting the sexual development of male horses. If both of the testicles remain in the abdomen, the horse will be sterile. Horses with an undescended testicle are sometimes

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  • Deworming and Internal Parasites

    Like any animal, horses are susceptible to a wide range of parasites. Of the approximately 150 species of internal equine parasites, some can cause serious harm while others are more of an annoyance. Usually parasite eggs or larvae arrive on the ground from the manure of infected horses. Another horse

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  • Hives and Skin Allergies

    The skin is the largest organ in the body and serves many important functions. In spite of its usefulness, a horse’s skin can also develop redness, itchiness or hives in response to various substances in the environment. These kinds of allergic reactions can be caused by things eaten, inhaled or touched

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  • Equine Motor Neuron Disease

    This relatively new disease was first diagnosed in 1990 in the state of New York. It’s still a rare condition and mostly confined to the United States. Symptoms Horse owners might first notice that their horse is eating plenty, but still managing to lose a lot of weight. He might have a short gait,

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  • Headshaking

    Head shaking shows up in horses as uncontrollable shaking, jerking or flicking of the head, with no obvious physical irritation causing the condition. While some cases may be mild, head shaking can be severe enough to make a horse dangerous or unsuitable for riding. Other symptoms that may occur alongside

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  • Limb Conditions

    Several disorders can affect the hindlimbs, forelimbs or hooves of horses. Some of these can lead to lameness or changes in gait. Hindlimb Conditions in Horses Stringhalt is a condition that causes the horse to jerk or hop, with the hind legs pulled up high before taking the next step. This results

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  • Hoof Health and Care

    Horse hooves are complex structures that tell you a lot about your horse’s health and wellbeing. They’re also susceptible to many problems. Here are a few hoof basics as well as some of the major hoof issues your horse faces. Anatomy If you look at the bottom of a horse’s hoof, you’ll see

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  • Hernias

    Hernias A hernia is a tear in the body wall of a horse that allows the internal organs to push through to a place where they don’t belong. There are several types of hernias. They can affect horses of any age or breed. Horses may have a defect at birth (congenital) that increases the risk of a hernia,

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  • Equine Movement Disorder

    Several conditions can affect how horses move. This includes ones that affect the spinal cord and nerves that run to the muscles as well as to the hooves. Stringhalt Stringhalt shows up in horses as a jump, jerk or hop in the one or both hindlimbs, with the legs tucked up high. Symptoms often start

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  • Immunodeficiency Disorders

    Immunodeficiency disorders in horses are rare conditions that prevent the immune system from protecting the horse against viral, bacterial or other types of infections. These disorders can affect different parts of the horse’s immune system. They may be present at birth or develop later on in the horse’s

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  • Exerional Rhabdomyolysis (Tying-Up)

    Horse lovers have observed this frightening disease for centuries. It’s been called azoturia, tying-up, cording up, holiday disease and Monday morning disease; the last two names reflect that symptoms are sometimes observed after hard work followed by a period of rest. In the last couple of decades,

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  • Metabolism

    Metabolism in horses — and in other animals — refers to all the body’s complicated processes that break down food, drink and drugs to provide nutrients and energy for living. Anabolic reactions generally happen soon after eating, to build structural parts of the body, such as muscles. Catabolic

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  • Respiratory Conditions

    Horses are highly susceptible to a wide variety of respiratory conditions. These can be bacterial, viral or mechanical in nature, or they may be caused by allergies. Some are temporary; others are chronic. Some are serious while others are less serious. Upper airway problems are usually mechanical while

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  • Nutrition

    You can divide horse nutrition into six categories: carbohydrates, protein, fat, vitamins, minerals and water. If you get the right feed for your horse, it might take care of the first five. Supplement the feed with plenty of water, and your horse should have all of its needs met. However, to be sure

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  • Kidney and Liver Problems

    Horses are rarely prone to kidney or liver problems. Damage to both organs is much less common in horses than it is in cats or dogs. However, some aging horses do suffer from progressive and irreversible diseases of the liver or kidneys. Unfortunately, problems with these organs are seldom diagnosed

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Location

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Office Hours

Our Regular Schedule

Monday:

8:00 am-5:00 pm

Tuesday:

8:00 am-5:00 pm

Wednesday:

8:00 am-5:00 pm

Thursday:

8:00 am-5:00 pm

Friday:

8:00 am-5:00 pm

Saturday:

9:00 am-2:00 pm

Sunday:

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Testimonials

Read What Our Clients Say

  • "Kath, thank you so much for being Greyson's vet, your gentle hand, compassion and great skill made all the difference for my buddy."
    --Deirdre Dekking, Portland
  • "Dr. Mertens is a very friendly, knowledgeable equine veterinarian (and a friend to the rest of the farmyard, including the chickens!). Always up to date on the latest in equine health, and even though Mertens Mammals is a small clinic giving you the personable experience, Dr. Mertens also has equipment for more advanced diagnostics and procedures!"
    —Ari Gordon, Boring
  • "I have been a client of Mertens Mammals for 10 years. Kath (Dr. Mertens) is the most kind, thoughtful and caring Vet I have ever had for my animals. I have 3 horses: my Appy "Breeze" who turns 30 this year, my Paint " Rocket " 14 and my other Paint "Fergie " 3 are all under Kath's care. I also had a dog "Cowboy" who I lost to cancer last July. Kath took care of him also. Dr.Mertens came out on Mother's Day about 7 years ago to treat Breeze for a cut above her right eye. After a few weeks of recovery we were happy to not have a huge scar. Kath also spent 2 hours with me 3 years ago when Rocket had a small case of colic. (Thank God). I couldn't ask for a better person to take care of my girls. Kath always calls to check in on the patients. When people ask who I use for my veterinary needs for my horses, I'm always proud to refer them to Mertens Mammals. I am so thankful for an honest and caring Vet. Thank you, Kath!"
    --Michelle Schatz, Portland
  • "I got looking at Sassy’s records and it will be 6 years in July when you first met Sassy—I feel so fortunate that you became her vet and have looked after her all these years. You are such a wonderful and caring doc and I know you always have Sassy’s best interests at heart. I also know I can always rely on you to help me or Sassy when needed. Thanks for all you do for both of us—will keep you posted on Sassy.”"
    —Judy Becker, Eagle Creek
  • "My horse, Pester, would have lost her eye had it not been for the great care and dedication by Mertens Mammals. They are truly there for you any time you need them. I could go on and on. Kath Mertens has been so good to us!"
    --Troy and Wendy Mohr, Estacada
  • "She has always been there for us. She is forever in my thoughts as the best vet. She saved our hours old filly from certain death. She knew exactly what to do in an instant after just seconds in seeing her. We are forever in your debt...thank you!"
    Barbara T.
  • "Thank you Dr Mertens for such a thoughtful and careful job with our sweet Daisy the Donkey this morning! She is well on her way to health again after that abscess!"
    Suzi C.