Core Vaccines

***This blog was originally written in January of 2020, and as of today, March 24th, 2020, times have changed significantly.  With Covid-19 causing the issues that it is, we feel it necessary to add the following statement.

Governor Polis on 3/20/2020, in Colorado Executive order 2020 009, made veterinarians part of the list of essential workforce to continue with “necessary procedures.”  For the safety and welfare of horses, the Mobile Veterinary Services vaccination schedule will continue as planned.  If delayed 3 or more months, depending on conditions, our horses will become susceptible to deadly diseases.  

As always, at MVS, we strive for clear client communication.  We will keep everyone informed to the best of our abilities as to the orders placed on us as veterinarians.  Please feel free to call with individual questions that you may have. ***

There is a long list of vaccines available to give our horses.  Owners and even veterinarians can get bogged down in the details, and that’s just based on the vaccines available. 

Then we start to talk about schedules for each group of horses.  Groups like Adult horses vaccinated in the past, Adult horses with no known or no history of vaccines, Foals (of vaccinated mares), Foals (of unvaccinated mares), oh yeah, and the broodmares!  Whew, I think that covers the horse population!!!

Really quickly a discussion of “just vaccines,” gets complicated.  Mobile Veterinary Services will always fall back on, “talk with your veterinarian to make a plan for YOUR herd and their individual needs.”  Here, we would like to discuss “core vaccines.”

What is a core vaccine? 

As defined by the AAEP (American Association of Equine Practitioners) a core vaccine “protects against diseases that are endemic to a region, are virulent/highly contagious, pose a risk of severe disease, those having potential public health significance, and/ or are required by law.  Core vaccines have clearly demonstrable efficacy and safety, with a high enough level of patient benefit and low enough level of risk to justify their use in ALL equids.”  It’s a mouthful, but what does it mean?  In the end, it means that they are safe, low risk, and designed and developed to protect horses and humans alike. 

These are the Core Vaccines recognized by the AAEP:

Tetanus:  Should be given annually.  If there is a question as to the status of a horse, they should receive a 2-dose series (4- 6 weeks apart).  Colts should receive a 3 shot series beginning around 6 months of age, second dose 1 month later, and another dose at 1 year old. 

EEE/WEE (Eastern Equine Encephalitis/ Western Equine Encephalitis):  Just like the Tetanus, it should be given annually, and they should go through an initial 3 dose series.  Conveniently, tetanus is often in a combination vaccine with these two. 

West Nile Virus:  As with the two above, West Nile should be given annually.  This is often in combination with WEE/EEE and Tetanus and can be given to colts and fillies in one shot on the same 3 dose schedule. 

Rabies:  Rabies is 100% fatal, in ALL species.  All youngsters should receive 2 vaccines starting around 6 months old (second one about 1 month later).  Then, every horse, every year should receive a booster. 

Every horse should receive at least these vaccines, every year.

It is important that these vaccines are handled correctly and managed at the appropriate temperature and environment to ensure that the vaccine is an effective and SAFE one.  This is the biggest reason that we recommend that you receive your vaccines from a licensed veterinarian.   If you ever have questions about your herd’s (no matter how big or small) vaccination protocol, please feel free to reach out to MVS!

Coronavirus and Veterinary Medicine

As we all hunker down for a few weeks of self-quarantine and social distancing, we want to alleviate any concerns our clients may have as it pertains to the potential transmission of coronavirus between horses and people.  While equine and bovine coronavirus has been present in the agricultural industry for quite some time, the disease is of gastrointestinal origin (diarrhea) and is not related the human respiratory virus (pneumonia) currently circulating our continent. 

As more research is conducted on this current respiratory coronavirus impacting human patients, it has become clear that the viral particles remain active outside of a human host for up to nine days.  This means that if one of your family members has COVID and sneezes directly onto your horse’s neck and you proceed to immediately rub your nose in that site on the horse’s neck, the horse could act as a fomite, thus delivering viral particles to you.  Otherwise, your horse is not a carrier of COVID and you cannot transmit the virus back and forth between each other. 

Here at MVS, we are still working at full capacity while taking measures to practice social distancing amongst ourselves and our clients.  If you are sick or feeling under the weather, please know that our doctors travel with a technician and can complete the appointment in your absence.  If you wish to be present, feel free to reschedule your appointment.

If you have any additional questions or concerns, please don’t hesitate to reach out to one of the MVS docs.  We’re here to help!

How to Select a Concentrate for Your Horse

With the variety of different feed and supplement choices available, it can be overwhelming to make decisions regarding your horse’s diet. It is important to remember that horses are grazing animals, designed to spend much of their day eating forage. Forage (grass and/or hay) should comprise most of your horse’s diet, at a rate of about 2% of his body weight per day. Of course, the nutrient profile of different forage sources can vary as well, so a hay analysis can provide more detailed information about nutrient content. 

When selecting a feed, be sure to look for the feed tag or guaranteed analysis. This tag describes the composition of the feed, including protein, fat, fiber, and mineral content. You will also find guidelines for recommended amounts to feed your horse, depending on his weight, workload, and stage of life.

What kind of concentrate does my horse need?

If your horse is not in heavy work and maintains an appropriate body condition score easily, he does not need high levels of concentrate added to a forage diet. A product called a ration balancer is perfect for these horses. Ration balancers are designed for the easy keeper to be relatively low in calories but contain the vitamins and minerals that may be lacking in a forage-only diet. For these horses, daily forage intake at 2% of body weight per day, a ration balancer fed by weight as directed, and access to a mineral block may be all that is needed.

For horses in heavy training, those with a higher metabolism, or those with compromised teeth, more calorie-dense concentrates may be beneficial. For example, a Thoroughbred racehorse will need extra calories from a concentrate to take in enough calories each day for race training, while an aged horse unable to chew adequately will need a forage substitute.

Examples of horses with varying dietary needs



Red, a 16-year-old quarter horse gelding. 

Job: light trail riding 1-2 days per week, easy keeper. Because Red has a less demanding job and maintains his weight well on hay alone, he doesn’t need extra calories from high-energy feeds. A ration balancer is a perfect option to ensure Red has the appropriate vitamin and mineral balance in his diet, without supplying extra calories. 





GiGi, an 11-year-old TB mare

Job: upper-level eventer.  GiGi is a high-level athlete, and as a Thoroughbred, she has a higher metabolism. She is in intense training 4-6 days per week, eats free choice hay, and needs the extra calories from a performance feed to maintain her condition. Many performance feeds offer high-fat content in addition to protein and fiber, as a more calorie-dense option.





Jack, a 25-year-old appendix gelding

Job: retired, hard keeper with many missing teeth. Lack of teeth means that Jack has a hard time chewing hay efficiently, which also puts him at an increased risk of choking. The best feed for Jack is a complete senior feed. The “complete” description means that this feed is formulated to meet all of his nutritional and caloric needs in the absence of hay. Of course, this means that a much higher amount of feed must be fed daily. Regular (non-complete) feeds are generally not safe or nutritionally balanced to feed in such high amounts. If you’re feeding a horse like Jack, remember to check the label of the senior feed to be sure it says ‘complete’.



 Remember, ALWAYS weigh your feed- the label instructions on the bag will have recommendations based on weight (The weight is NOT 1 coffee can…) It is much easier to adjust your horse’s diet when we know exactly how much he is consuming. The easiest way to do this is to put your feed scoop on a food scale, tare it, add feed to desired weight, then draw a line on your scoop so you can feed consistently at every time. Another important note is that feeds are not all the same weight, so if you switch feeds, 2lbs of feed A is probably not the same amount in your scoop as 2 lbs of feed B. As always, if you have questions or would like help selecting a concentrate, consult with your veterinarian.