Nancy Diehl, VMD, MS

Prior to attending veterinary school, Dr. Nancy Diehl completed a master’s degree in animal science while studying stallion sexual behavior. Later, she completed a residency in large animal internal medicine at the University of Pennsylvania’s New Bolton Center and worked in equine practices in Missouri and Pennsylvania. Diehl also spent six years on faculty at Penn State, where she taught equine science and behavior courses and advised graduate students completing equine behavior research. Additionally, Diehl has co-authored scientific papers on stallion behavior, early intensive handling of foals, and feral horse contraception. Currently she works as a racetrack regulatory veterinarian and lives in central Pennsylvania.

Articles by Nancy Diehl

Is It Okay for My Horse to Live by Himself?

Vet and equine behavior expert Dr. Nancy Diehl shares the reasons horses live best in groups. Read More

What Should I Do if My Horse Panics at the Electric Fence?

A veterinarian and horse behavior expert addresses a senior horse's bad experience with an electric fence. Read More

Why Does a Horse Buck?

An equine behavior expert and veterinarian explores the reasons why a horse might buck. Read More

How Can I Tell if My Horse is Stressed?

Our expert shares her thoughts on what causes stress for horses and how they respond to stressful situations. Read More

Why Does a Horse Lie Down?

Learn about equine sleep patterns and how to tell if the amount of time your horse spends lying down is normal. Read More

How Can I Tell if My Horse is in Pain?

Learn the signs that your horse's behavior might be related to pain from a veterinarian and equine behavior expert. Read More

How Do I Get My Horse to Respect Me?

Dr. Nancy Diehl shares how you can earn your horse's respect through consistent training. Read More

Does My Horse Love Me?

Do we know if horses feel love toward humans and each other? Read More

Breeding a Laminitic Mare?

Q: Is it safe to breed a mare that is prone to laminitis? A: There are several considerations that go into the decision to breed a mare that is prone to laminitis. Is the laminitis an occurrence that can usually be prevented by good dietary Read More

Recurrent Colic Q&A

My horse has recurrent colic that's usually fairly mild, but she had surgery last August due to a twist. She has done well until recently when she had another mild attack. A biopsy taken during surgery showed inflammation. No other problems were Read More

Feeding Laminitic Broodmares

My best friend's broodmare has unilateral laminitis (laminitis in one front hoof); she is a 19-year-old Quarter Horse and is currently five months pregnant. The concern is what to feed her to keep the foal healthy, and to keep her from suffering. Read More

Protein-Losing Enteropathy Diagnosis

My 3-year-old Quarter Horse gelding has been diagnosed with protein-losing enteropathy, but I can't find a whole lot of information on it for horses. The veterinarian says that if the steroids and antibiotics don't work, he doesn't think Read More

Cushing's and Seizures?

Seizures are rare in the horse, and adult horses especially have a high seizure threshold. Cushing's disease can cause seizures, but they are very rarely seen with this disease. Read More

Wry Nose in Horses?

I would like information on wry nose (laterally deviated rostral maxilla). I had a foal born with it and never heard of it before then. I would like to know what causes it and any other information about this condition. Also, how common is it Read More

Herd Bound Horses

I was wondering if you could help me. For a friend, I look after a 15.3-hand mare who is six years old. The horse had a fairly bad start in life as she was first abandoned in a stable, then in a field. She has luxating patellas in both hind Read More