by Holly J. Helbig, DVM, Equine Technical Services Veterinarian, Zoetis

PREVENTION IS PRIORITY

Given how difficult it is to stop the spread of certain infectious diseases, prevention needs to be our top priority. Prevention is in the textbooks we read, and equine vet conferences always seem to have a good panel of speakers on biosecurity. Of course, as veterinarians we advocate for prevention with our clients because we care about it and it's our duty.

We remind clients that their horses are particularly vulnerable at shows, races and events. We emphasize a 2-week quarantine for new horses welcomed at barns and after transport with horses outside their normal population. One gift the pandemic gave us was heightened awareness of contagious diseases.

Considering the "not fun" factor of an outbreak, one "fun fact" I love sharing is "Did you know a horse can sneeze and shed a virus reaching half the length of a football field?" That's 50 yards (150 feet) according to the Equine Disease Communication Center (EDCC).

Let's not wait to prioritize biosecurity measures until it's too late. Let's focus on prevention first.

TRUST THE SCIENCE AND VACCINATE

Routine preventitive care and vaccination is critical; for all horses at all stages of life. No matter if the horse travels, lives at a faciity where others travel; or simply is exposed to other horses across the fence line, the end game is the same - healthy, happy and protected.

Although vaccinating doesn't guarantee prevention of disease, science has shown that it significantly reduces the risk of clinical signs as well as the duration of disease. The AAEP divides vaccinations into core and risk-based. Core diseases are those that are endemic, pose risk of significant harm to a horse and are potentially significant to public health. Core diseases include Eastern equine encephalomyelitis, Western equine encephalomyelitis, tetanus, rabies and West Nile virus. Core EQ Innovator is the only approved vaccine for horses that covers all five core diseases in a single injection.

Risk-based vaccines that target diseases such as equine rhinopneumonitis (EHV-4/1) and EIV are often chosen based on the nature of commingling, travel and geographic location. Because respiratory viruses are the most common risk-based viruses, most organizations overseeing performance horse events require horses to be vaccinated for EHV-1 and -4 and EIV every 6 months.

The AAEP recommends that all horses get vaccinated 2 to 3 weeks prior to traveling.

IMPROVING BIOSECURITY THROUGH HEIGHTENED COMMUNICATION

The transmission of information is essential for effective outcomes. The governing bodies regulating horse shows and large equine events, along with the veterinarians involved, need to have an action plan in place before potential biosecurity events occur. Like COVID-19, social and economic impacts are at risk. Alternating perspectives of all parties involved can often make a plan of action difficult to execute.

On the management side, show owners may not want to lose entry money or make it publicly known that there may be a biosecurity threat at their show. It's not good for business. Trainers and owners may be hesitant to inform others of their sick horses out of fear that they'll be blamed as the source of disease transmission. Many febrile horses are treated by trainers, sometimes for days before getting a veterinarian involved. Veterinarians may feel obligated to protect their clients and have a mindset that if a horse is already shedding a virus, he's already shed to neighboring horses at this point. All these mindsets are a recipe for disaster.

Let's also give a huge shoutout to the EDCC, whose sole purpose is to help track equine outbreaks and improve the welfare of horses by communicating real-time alerts across the country.

HORSES THAT TRAVEL: SPREAD THE WORD, NOT THE DISEASE

Most horse owners travel with their horses at some point during the year. After all, most horses are part of the family, and for equestrian enthusiasts, some of the best vacations are spent at events accompanies by their horse. The following are simple guidelines you can follow:

• Be up to date on all core and risk-based vaccinations
• Provide proof of a negative Coggins test within the last year (6 months for some states/events)
• Have a current certificate of veterinary inspection, required for interstate travel
• Ensure manure is removed and the stall is cleaned and disinfected prior to unloading a horse from his trailer to enter the show barns
• Take your horse's temperature upon arrival at an event, twice daily during an event and at departure
• Do not share tack, cleaning or grooming equipment
• Minimize nose-to-nose contact, including avoiding sharing rags to wipe horses' faces
• Isolate your horse for 2 to 3 weeks when returning from an event and monitor for any signs of disease
• If a horse is coming from a previously infected farm or event, a nasopharyngeal swab and culture may be warranted
• Communicate with your veterinarian if your horse(s) show any signs of infectious disease or if other horses at the event are reported febrile

The AAEP has an extensive and resourceful link on its recommended biosecurity guidelines. Many governing bodies of horse shows also offer information guidelines on biosecurity.

THE NEED TO RETHINK POTENTIAL IMPACT

No one around the world grasped just how large the impact of COVID-19 would be. Beyond the enormous human and economic impact, the pandemic exposed the weaknesses of organizations, lack of preparedness and poor response of health care systems.

Currently, outbreaks of more devastating diseases such as equine herpesvirus, equine herpes myeloencephalitis and strangles continue to populate our newsfeeds and social media. In the future, the equine community may be confronted with other viruses whose combination of virulence, transmissibility and other characteristics pose even greater danger.

Sometimes biosecurity measures get neglected. We underestimate the potential impact to our horses' health, along with the economic impacts to owners and the industry. The necessary measures continue to require leadership, time, education, routine preventive care and public awareness.

FREQUENCY OF VISITS

All horses should have a veterinary oral and dental examination at least annually. For horses 2-5 years, over 20 years, and those with known dental pathology, more frequent visits may be necessary. Decisions regarding specific frequency of visits should be based on the individual needs of the horse.

HEALTH EVALUATION:

SUBJECTIVE

History, including evaluation of:

• Previous health concerns
• Breed, life stage and life style (activity level)
• General housing and management
• Current ration/diet/pasture
• Bitting and tack requirements
• Behavior/vices

OBJECTIVE

Teresa Burns, DVM, PhD, DACVIM(LAIM)
Ohio State University College of Veterinary Medicine, Columbus, Ohio

Obesity and its associated health complications in humans and veterinary species are epidemic in industrialized countries, and horses are no exception. Additionally, as horses are now routinely living into their third and fourth decades, the prevalence of diseases of aging, such as pituitary pars intermedia dysfunction (PPID) (sometimes referred to as equine Cushing's syndrome), is also increasing.

Equine obesity and PPID are both associated with insulin dysregulation (ID), a state of disordered insulin and glucose dynamics that encompasses basal hyperinsulinemia, exuberant pancreatic response to carbohydrates, and tissue insulin resistance. Affected horses can display 1 or more of these abnormalities, and equine ID is pathophysiologically and contextually diverse. However, given the established link between hyperinsulinemia and laminitis, as well as the fact that any manifestation of ID can result in hyperinsulinemia, ID is an important point of intervention for therapy and prevention of laminitis in the setting of equine endocrine disease. Establishing a diagnosis and characterizing the severity of ID are essential to implementing and monitoring therapy, and the first line of therapy for mitigating hyperinsulinemia must be nutrition and diet management.

Take-Home Points