Equus August 2018

A wild ride “Self-Defense for Trail Riders” (EQUUS 489) reminded me of something that happened to my mom while she was out riding in the Santa Susana Mountains in California in the late 1960s. A man approached her and grabbed the reins, trying to get control of her horse. Luckily, the horse we had then, Freckles, was about 16 hands and had been a calf roper, so he took off up the mountain when my mom kicked him. The man who’d grabbed at her, along with some other people, chased my mom and Freckles on dune buggies, but they just kept running until they were safely back at the ranch where we boarded our horse. At the time, everyone thought my mom had simply encountered a bunch of hippies. It…

After an exasperating day at work, take a deep breath and leave your stress at the barn door: A new study shows that not only can horses recognize a person’s angry facial expressions, they are likely to remember and react to the signs of a bad mood in the future. Working at the universities of Sussex and Portsmouth in England, researchers showed 48 horses photographs of unfamiliar people. Half of the horses saw a photo of a happy, smiling person. The other half of the horses were shown a photo of a person with an angry scowl. Three to six hours later, either the person depicted in the photo or another unfamiliar person adopted a neutral expression and entered each horse’s stall while observers documented the horse’s reaction. Specifically, the…

The data showed that, in cases of forelimb lameness, a horse’s head and withers both dropped when the sound foreleg was on the ground and rose when the lame leg was bearing weight. The movement of a horse’s withers can signal whether lameness originates in a front or hind leg, according to a new study from Sweden. The process of detecting lameness in a particular limb typically begins by watching movement of the head and pelvis. Generally, a forelimb lameness causes a head nod, while a hind limb lameness causes asymmetries in pelvic movement: The mid-pelvis will drop more on the sound hind limb compared to the lame limb. Often, however, a horse will develop a “compensatory” head nod in a hind limb lameness as he redistributes his weight to…

Aural plaques—the white, crusty growths that some-times appear on the inside of equine ears—can contain several types of equine papillomavirus (EPV), according to a new study from Brazil. Also known as papillary acanthoma or ear papillomas, aural plaques are harmless but can be unsightly. They are thought to develop when EPV is spread by black flies, which deposit the virus on the inside of the ear’s pinna0 while feeding. The growths are notoriously difficult to treat, and the most effective method—topical application of the antitumor drug imiquimod—is lengthy and difficult to deliver. EPV is associated with a variety of skin growths in horses, ranging from warts to sarcoids0. So far, eight different varieties of the virus have been identified, based on their genetic structure. To learn which EPV varieties might…

Early results suggest that a modified version of the surgical technique commonly used to correct “roaring” in horses provides a longer lasting fix for the noisy respiratory condition. Roaring is characterized by a harsh, rasping noise as an exercising horse inhales. It is caused by recurrent laryngeal neuropathy, a progressive paralytic condition of the main motor nerve of the laryngeal musculature that causes the arytenoid0 to droop into the airway. The condition can progress to the point that the horse is unable to exercise because of airway occlusion. In laryngoplasty, the surgical procedure most often used to correct roaring, the paralyzed cartilage is sutured to the cricoid cartilage to keep the airway open. After surgery, however, the sutures often loosen, allowing the flap to again obstruct the airway. “Partial failure…

Areas of mineralization seen in tendons and ligaments during ultrasound exams are not necessarily associated with lameness, according to a new British study. In ultrasound examinations, high-frequency sound waves are used to produce images of organs and other structures within the body. Areas of mineralization (calcification or ossification) in soft tissues appear as bright spots on ultrasound images, but their clinical significance is often unclear. To explore the implication of soft-tissue mineralization, researchers at the Royal Veterinary College (RVC), London, examined the ultrasound images and clinical records of 27 horses brought to the RVC Equine Hospital over a 16-year period because of lameness. The most common location for mineralizations was the deep digital flexor tendon, found in 10 of the study horses. Eight horses had mineralizations affecting the suspensory ligament…