Breeding Soundness Exams for Horses

As humans, we naturally think that we can improve on what Mother Nature has given each species, including horses – or should I say especially horses.  In some cases, we may have succeeded.  Just look at some of the great accomplishments of famous horses in just about every breed.  In fact, the number of different breeds we have today may well have resulted from improvement efforts.  Enough on that – here are some reasons why a breeding soundness exam is important for both the stallion and the mare prior to breeding.  Since the breeding season for horses will be here before long (starts in May and runs through September) it’s time to start preparing for breeding – including getting a breeding soundness exam scheduled.

There are several reasons to want to perform this exam on both the mare and the stallion.  The main reason is to be as sure as possible that a foal will result from the stud and mare getting together.  A lot of things can affect that end result, including condition; location of bacterial colonies, structural defects, and the list goes on.  I’ll address a few of the things that are examined without getting into too much detail and give a couple of sources for folks who want all the information.

For the stallion, it is a good idea to start with history.  Check to see what his performance was the previous breeding season.  If it was OK, then move on to the next item on the checklist.  If low (lower than expected foals born) then some time spent researching why that happened would be in order, looking for such things as reproductive history and management of both the stallion and the mare (breeding, feeding, and housing).  The stallion should have positive identification – make sure you are getting what you are paying for – and should be free of Equine Infectious Anemia, Equine Viral Arteritis, and Contagious Equine Metritis.  Conformation should be checked, including lameness, vision, inherited defects, Parrot Mouth, and chryptorchidism, to name a few of the items checked during an exam.   Genitalia are examined either physically or though use of ultrasound equipment.

Semen is collected and examined for pH, sperm motility over time, bacterial cultures, and the number of abnormal sperm cells.   Semen collection should be conducted by people who are trained or have experience.  A lot of bad things can happen during the collection process, including getting kicked. All this is pretty important and helps ensure that the stallion is physically able to breed and have a high success rate.  For more detailed information on breeding soundness exams of stallions, visit the LSU Vet School page titled Stallion Breeding Soundness Examination.  (If you get a message that Adobe Reader is blocked for this web site, click OK to trust the site.)

For the mare, many of the same recommended steps are taken in a breeding soundness exam.  Identification is verified and her reproductive and medical history is reviewed.  She gets a complete general and physical examination along with a detailed examination of her reproductive organs.

The physical exam includes checking temperature, heart rate, respiratory rate, teeth, eyes, mucous membranes, superficial lymph nodes, and checks for other physical abnormalities. Hereditary defects such as Parrot Mouth and limb abnormalities should be noted, along with anything that may interfere with the mare’s reproductive performance.

The reproductive exam includes a perineal inspection, rectal palpation and ultrasonography, a speculum examination of the vagina, a uterine culture and cytology to rule out a uterine infection, and a uterine biopsy.  For more detailed information on the BSE for mares, read the article written by Dr. Troedsson of the University of Florida, Breeding Soundness Examination of the Mare.

Horses have been able to reproduce on their own for a long, long time, so maybe some folks will ask why we don’t just let nature take its course?  Well, nature does take its course.  We just want to try and improve the odds a bit by making sure that all the parts are in the right place and not being influenced by some other outside force, like a uterine infection or a sore hoof.  If we are going to take time effort and expense to try and get a healthy foal, the least we can do is try to make sure all the conditions are right for the magic of a new foal to happen.

Contagious Disease Control/ Vaccinations

With spring finally here many horse owners are beginning to think about the many adventures that they can have this year with their equine partner. When traveling to shows, trail rides, new barns or coming in contact with new horses there are a few things you should be sure your horse is protected against.

Contagious diseases are those that can be spread from one animal to another. Control programs should be targeted at reducing exposure to disease-causing agents and increasing disease resistance. To reduce contagious disease exposure to resident horses, it should be required that new horses to the property or horses that are traveling have a negative test for Equine Infectious Anemia (EIA, “Coggins Test”) and have been appropriately vaccinated and dewormed before they arrive. New horses should be received and maintained in an isolation barn or paddock for 30 days to ensure that sick horses or horses incubating a contagious disease are not inadvertently introduced into the farm population. The isolation area should be physically separated from the resident horses. Separate equipment and preferably separate personnel should be used to take care of the isolated horses. Isolated horses should be cared for after the resident horses. During the 30-day quarantine period, horses should be monitored daily for signs of contagious disease. Common signs to look for are decreased appetite or activity level, coughing, fever, and discharge from the nose or eyes.

Additionally, any resident horse that becomes ill with a potentially contagious disease should also be promptly isolated. Isolation should continue for at least 10 days after all symptoms are gone. Separate equipment and personnel should be used to take care of sick horses. If separate personnel are not available, sick horses should be tended to after the other horses on the farm. Stalls that have housed sick horses should be thoroughly cleaned, disinfected, and left empty for as long as possible before being used by other horses.

Disease resistance in horses can be enhanced by proper housing, feeding, exercise, and the use of vaccines. Vaccines are health products that trigger protective immune responses and prepare the vaccinated individual to fight future infections from disease-causing agents. There are many vaccines and vaccine combinations available for use in horses. The specific vaccines needed by a particular horse will depend on several factors, including the horse’s age, exposure to other horses, and geographic location. Your veterinarian will help you determine the vaccination program best suited for your horse.

In general, all adult horses should be vaccinated against tetanus, eastern and western encephalomyelitis (EEE and WEE), west Nile virus (WNV), and rabies each year. Horses that are exposed to other horses during shows, trail rides, etc. should also be vaccinated for influenza and equine herpes virus 1 and 4 (EHV- 1 and EHV-4). These vaccines may need to be boostered every three to six months for effective immunity. Pregnant mares should be vaccinated against EHV- 1 the fifth, seventh, and ninth months of gestation. Pregnant mares should also be boostered for tetanus, EEE, WEE, WNV, EHV-1, EHV-4, and Influenza, four to six weeks before foaling. Only “killed” vaccines may be used in the pregnant mare. Foals from appropriately vaccinated mares usually start their vaccinations when they are three to four months old. Foals from unvaccinated mares need tetanus antitoxin right after birth and should start their vaccines at two to three months of age. Many other vaccines are available, and may be recommended in your area. Again, work with your veterinarian to set up a vaccine protocol specific to your horse’s individual needs.

Adapted from Health Care for Horses, Scott Pleasant, D.V.M. Virginia Cooperative Extension.

Spring Pasture Checklist

Spring is an important time of year for pasture care. Here is a list of things you can do in the next couple months to get your pastures looking great.

1.     Plant Seed The best time of year to seed a pasture is fall. However, spring is an acceptable time of year if you missed the fall deadline. Planting dates will vary with where you live.  Your county Extension office is an excellent resource to determine the best spring planting dates for your location.  Make sure you keep horses off newly seeded pastures until the grasses are well established and you have mowed 2 - 3 times.  If you seed in the spring, be prepared to let the pasture rest for about a year.  The newly planted forage needs to be able to develop strong roots in order to withstand grazing.  It is also the most appetizing grass and will have a hard time developing under grazing pressure.  Planting dates for NC: http://www.ces.ncsu.edu/wp-content/uploads/2014/03/A.-Planting-Guide-for-Forage-Crops-in-NC.pdf

2.     Take Soil Samples See if your pastures need any nutrients and/or lime. Once the frost is out and the soils have dried, samples can be taken. Contact your county Extension office for more information and to obtain soil sampling forms and boxes.  There is a $4 fee/sample in place until April 1^st.*

3.     Fertilize As stated in 2, test your soils first, so you know how much you need. Often, only Nitrogen is needed in pastures.

4.     Spray Herbicides Spring is a good time to spray annual weeds as it prevents them from getting established. However, mowing is usually sufficient for annual weed control unless weed densities are high.

5.     Check fences Snow/ice and deer can be hard on fences. Check them before you turn out the horses.

6.     Plan your grazing system Think back to last year whether you had enough grass or if the horses turned the pasture into a putting green or mud pit. You may need to supplement your horse with hay during certain times of the grazing season and set aside a sacrifice area when the pasture needs a rest.

7.     Let the grass grow Keep the horses off the grass until the ground firms up and the grass has a chance to get growing. Once the grass is about 6 - 8" tall, start easing the horses onto the pasture in 15 minute daily increments (15 minutes the first day, 30 minutes the second day, 45 minutes the third day, etc...), until the time on pasture reaches 5 hours a day, after which the horse can be given unlimited access.

Original article written by: B. Wieland, University of Minnesota

Spring Pasture, Fructans and Founder

We have officially sprung forward again.  That time of year when days are gradually getting longer and temperatures are becoming warmer.  With warmer weather and longer days our pastures are starting to “green up” and our equine friends are ready to have at it!  However, before you turn them out and give them free reign, please read the following article from University of Minnesota and use it to make smart grazing decisions which will hopefully help protect your animals from founder and digestive upsets this Spring. 

 All horses are subject to digestive upsets associated with spring pasture. The content of highly fermentable carbohydrates in pasture can be overwhelming to the un-adapted digestive system of horses. Ponies, because of a gene that allows them to survive on limited amounts of medium quality forages, and overweight horses, because of insulin resistance and associated high levels of circulating pro-inflammatory agents, are particularly susceptible to pastures with high fructan contents (commonly found in spring). 

Fructans are specially adapted sugars that are found in cool season forages (most grass pasture species in MN are cool season). Fructans derive their unique properties from the bonds that cannot be digested by the normal enzymatic mechanism for digesting soluble sugars (simple sugars like sucrose) in the stomach and small intestine. Fructans get to the hindgut and are fermented by bacteria into lactic acid and volatile fatty acids (VFA). VFA are normal products of the digestion of digestible cellulose and other cell wall constituents of forages, making them easily digestible by horses. However, lactic acid is not used efficiently by other bacteria or efficiently absorbed form the hind gut. The resulting accumulation of lactic acid into the hindgut is one of the most direct causes of colic, founder, and laminitis in horses on pasture. Many horses can graze pastures without succumbing to laminitis if they have time to adapt their digestive tract and develop a hindgut buffer that reduces lactic acid accumulation. 

Fructans are produced through photosynthesis that occurs in the leaves of plants during day light. The sunnier the day, the more photosynthesis, and therefore, the more fructans. During the night (dark), plants use the fructans for plant growth and energy storage. Many cool season grasses store fructans in the lowered 2" of the stem just above the soil line. However, temperatures at night are critical. If the temperature is not above 40F at night, the plant will not grow and the fructans remain in the leaves in high concentrations. 

So, when is the best time to graze in order to avoid fructans? The answered, as usual with complicated issues, is it depends. There are daily cycles of high and low fructans levels. When you have warm days and cool nights (below 40F) don't graze sensitive horses, and limit grazeing of all horses. If the weather is sunny during the day and warm at night, then horses should be grazed early in the morning when fructan levels are lowest. 

There are also plant maturity cycles of fructans. The first growth of grass in spring, has very low levels of fructans. While fructans may be low in early pasture growth, indigestible cellulose and lignin is also low. High cellulose and lignin decrease intake. Because of this relationship, horses tend to eat more, and even though the fructan levels are low, total intake of fructans may still be high due to the volume of forage consumed. Managing pastures so that horses do not overgraze (fructans are stored in the lower 2") will help reduce fructan intake. However, horses are selective grazers and may choose to eat high fructan portions of the plant. The condition of the entire pasture must be monitored daily, as horses tend to select the highest fructan plants in a pasture to graze. 

Finally, stressed pasture plants can cause fructan levels to increase. For example drought or frost can increase fructan levels by 30 %. As a general rule, horses that have high energy requirements can handle fructans as long as overall energy balance is taken into consideration.
The classes of horses that can handle high fructans, if they are adapted to them slowly, include; growing horses (just don't overfeed grain when fructans are high), lactating mares, hard working horses, thin horses (that are not compromised by disease or parasites) and breeds that are known to be hard keepers like Thoroughbreds. The general rule for horses that should avoid fructans (i.e. avoid grazing) are easy keepers, ponies, and any overweight horse.

The fructan question is very confusing, when in doubt consult you veterinarian, use grazing muzzles to reduce pasture intake, and keep sensitive horses off pasture completely. Sensitive horses usually include horses that have previously foundered. Founder, also known as laminitis, is an inflammation or swelling of the laminae or tissues that connect the hoof wall to the coffin bone. Prevention of founder is dependent on identifying and correcting an underlying cause, as laminitis can be triggered by many diverse events. Prompt treatment of laminitis is important. Treatments are aimed at controlling pain and inflammation, encouraging circulation to the laminae, and stabilization of the foot and coffin bone. Recovery from laminitis depends largely on the amount of damage done to the laminae and the general health of the horse. Treatments vary from corrective trimming and shoeing to surgery. Managing a horse's weight, controlling access to pasture, and close cooperation between horse owners, veterinarians, and farriers are important ways to avoid and manage founder.

~Original Article Written by: Larry Lawrence, PhD, Kentucky Equine Research and Stephanie Valberg, DVM, University of Minnesota  

Equine Industry Referendum

The North Carolina Horse Council (NCHC) will be holding an equine industry referendum to extend the Horse Industry Promotion Assessment.  This assessment was first authorized in 1999 through House Bill 1529.  The referendum will be conducted in all of North Carolina’s 100 counties on Tuesday, March 11, 2014.  You may vote in your county during Extension office hours.  To find your voting location, please go to http://www.ces.ncsu.edu/local-county-center/

Anyone who is a horse owner or leaser, over the age of nine as of January 1, 2014, can vote.  That is any North Carolina resident who has complete or partial ownership or lease of an equine (horse, pony, mule, donkey or hinny).  Horse owners will be able to vote on whether or not to extend, for three years, the $2.00 per ton assessment being paid by manufacturers of horse feed sold in North Carolina.  If the referendum passes, each feed manufacturer or distributor (not retailer) will send a nickel per 50 pound bag or $2 per ton to the NC Department of Agriculture.  The Department of Agriculture consolidates the funds and sends them to NCHC. 

The feed assessment has provided essential funding to the North Carolina Horse Council to meet a wide variety of needs throughout the horse industry.  The economic impact of the horse industry is estimated to be over $1.2 billion annually, so it plays a huge role in supporting the NC economy.  Employment of more than 10,000 people in North Carolina are directly or indirectly linked to the industry.  This small self-assessment is just one way NCHC can expand services to horse owners and maximize the economic benefits of horse ownership.

The funds are used for 4-H and other youth and educational programs, trails advocacy, equine research, representation of horse interests in government, marketing programs, enforcement of horse laws, and improved public awareness of diseases and other threats to horses’ well-being.  Many other North Carolina agricultural commodities have similar voluntary assessment programs such as beef, strawberry, peanuts, and soybean.  The assessment is not a tax since it is not for the support of a government; the proposed self-assessment is for the interests of horse owners. 

There will also be an absentee balloting system put in place for owners who are not able to get to the Extension Offices on March 11, 2014.  Between February 24 and March 10, horse owners or leasers may visit or phone the County Extension Center and request a ballot and absentee registration form.  These must be turned in to the Extension Office by March 10, and will be counted along with others on March 11.  All voters must sign a certificate of eligibility, swearing that they are eligible, and will provide proof of such if asked.  “Yes” indicates a vote in favor of continuing the assessment.  “No” indicates a vote against continuing the assessment.

The assessment is refundable if you choose not to participate in the program.  You must simply save your feed receipts, send them to the Horse Council, and receive a full refund of the assessment you have paid.  The request must be submitted to the North Carolina Horse Council within one year of purchase and must be accompanied by proof of purchase.  The estimated average cost per horse per year for this voluntary assessment is $1.80.  Based on collections from the first two years of the assessment, annual receipts have generated approximately $200,000.