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Monday, April 6, 2015

Crown Rust in Oat Hay

Question: The cover crop of oat in my newly seeding alfalfa hay field has rust. The oat will get cut and baled with the alfalfa, and I'm wondering if this is going to be a problem for the horses?

 Response: Crown rust is a fungus that affects the leaves of oat, and spreads from leaf to leaf via spores. There are some varieties of oat that are more resistant to crown rust than others. 
Crown rust on oat should not pose a major health risk to your horses once baled. However, crown rust will likely decrease the nutrient value of the hay (decreased protein and digestible energy levels) and may decrease the palatability (the horses willingness to ingest the hay) of the hay. Therefore, it is recommended that you test the hay for forage quality and supplement with a vitamin/mineral mix or concentrate as needed. 

More importantly, crown rust may make the hay dusty, which could lead to respiratory issues. Feeding the hay outdoors and pulling apart the flakes prior to feeding may help to decrease the dust level. Wetting (not soaking) the hay with water prior to feeding will also help reduce the chance the horse will inhale the dust and spore particles. 

 Author: Krishona Martinson, PhD, University of Minnesota  


Hay Consumption

Question: How many square bales does a horse eat a day. Is it necessary to have hay/feed in front of a horse all day.
Answer: It is difficult to estimate how many small square-bales of hay a horse needs each day since bales vary in size and weight. Its better to feed based on weight. The average adult horse required about 2% of its bodyweight in feed (hay plus grain) each day. For example, a 1,000 adult horse at maintenance would require 20 pounds of feed daily. If your small square-bale weighs 40 pounds, then the horse should be fed half the bale each day. If the bale weighs 80 pounds, then one quarter of the bale would be required each day.                 

If you are feeding grain, then subtract that amount from the hay meal. For example, if you are feeding 5 pounds of grain, then reduce the amount of hay fed by 5 pounds. Using the above example, the hay ration would then be reduced from 20 to 15 pounds. Adding the 5 pounds of grain to the 15 pounds of hay fed daily would help ensure the horse was receiving 2% of their bodyweight in feed each day. It is also a good idea to assess horse body condition each month and adjust the amount of hay (and grain) fed as needed.                      

 It is not necessary for horses to have feed in front of them all day. In fact, this practice can lead to obesity if high quality, energy dense feed is offered without sufficient exercise. Feeding 2 to 4 small meals throughout the day, that equal 2% bodyweight, is ideal since horses evolved to consume several small meals throughout the day. However, feeding more than two meals throughout the day is not feasible for many horse owners. One management method that has proven to extend foraging time while allowing horses to remain on a controlled diet in the use of slow feed hay nets. A recent study at the University of Minnesota found that horses took 3.2 hours to consume a hay meal when fed off the stall floor and 6.5 hours to consume the same hay meal when fed from a slow-feed hay net. Researchers concluded that slow-feed hay nets represent simple and affordable management tools for extending foraging time when meal feeding horses. For more information on the hay net study, click here.

 By: Krishona Martinson, PhD, University of Minnesota

Trees to Plant in a Horse Pasture

Question: Our horses pasture is along a residential road. In attempts to filter out the exhaust, we are proposing to plant shrubs/trees along the inside of our fence. The city requires these plantings to be on "our side" of the fence. What trees/shrubs are "safe" for horses, in case their curiosity results in a nibble?

Answer: It is more practical to provide a list of trees that should not be planted and why. Do not plant:

Plants in the cherry family (Prunus species). For example, chokecherry, most parts of the plant contain cyanide which causes death if ingested. Black cherry is a common food source of eastern tent caterpillars which are associated with Mare Reproductive Loss Syndrome.    

Ornamental shrubs including rhododendron, Japanese yew, and oleander. These ornamental shrubs will cause death when ingested in small amounts.     

Be cautious when planting the following trees:

Oak. New buds and green acorns hulls contain tannins. Ingesting large amounts for more than a few days can lead to diarrhea, colic, swelling, and frequent urination.

Maple. Ingestion of 1 to 3 pound of dried or wilted leave (not fresh leaves) can cause toxicity. Signs include red/brown urine, depression, and possibly death.  

Female boxelder trees. Seeds may contain a toxin that is known to cause seasonal pasture myopathy. Male trees do not produce seeds.

Oak, maple and boxelder trees are common in horse pastures. They can be planted, but owners should be aware of the potential issues. The only way to ensure the horse will not ingest parts of the tree is to fence the horse out of the trees. Most horses who are well fed will rarely seek out ‘alternative’ food sources like trees. 

By: Krishona Martinson, PhD, University of Minnesota

Hay Soaking

Questions: Should I always be soaking my horse's hay, or is this something reserved for horses with respiratory problems or other health conditions such as laminitis?

 Answer: Soaking hay in water is a common strategy used to manage horses diagnosed with laminitis, equine metabolic syndrome (EMS), polysaccharide storage myopathy (PSSM), and hyperkalemic and periodic paralysis (HYPP). Soaking hay should not be done, and is not necessary, for healthy horses because essential nutrient are leached during the hay soaking process.

 Hay is soaked for horses diagnosed with PSSM, EMS and laminitis to remove some of the nonstructural carbohydrates (NSC) from the forage; NSC are water soluble. Horses diagnosed with PSSM should have an overall diet of ≤10% NSC, and horses diagnosed with EMS and/or laminitis should have an overall diet of ≤ 12% NSC. Although forage is the major component of a horses diet, when feeding horses diagnosed with these diseases, make sure to account for NSC content in any grain, supplements, and treats the horse is also receiving.

Before soaking hay, it is critical to have the hay tested for nutritive value. Legumes (i.e. alfalfa) tend to be lower in NSC compared to cool-season grasses (i.e. timothy), and hays containing legumes may not need to be soaked. Soaking most grass hays for 15 to 30 minutes will remove enough NSC for horses diagnosed with PSSM, EMS, and/or laminitis. However, testing forage both before and after soaking is necessary to ensure recommended levels of NSC are being met. Soaking forage for greater than 60 minutes is rarely necessary and may actually be detrimental due to excessive leaching of essential nutrients and loss of dry matter.

 For horses diagnosed with HYPP, soaking hay is water is necessary to leach potassium (K), which is water soluble. Unfortunately, legumes and cool-season grasses tend to be very high in K and often exceed the recommended 1.1% maximum over-all diet for horses diagnosed with HYPP. For horses with HYPP, soaking hay for 60 minutes is often necessary. If soaking hay for 60 minutes does not achieve the recommended amounts, owners may need to consider feeding a complete feed that formulated for horses diagnosed with HYPP.

 For horses diagnosed with respiratory disease, including heaves, thoroughly wetting the hay is sufficient. Wetting the hay is different from hay soaking. The goal of wetting hay is to weigh down
mold and dust particles so they are not inhaled. Horses diagnosed with respiratory problems do not have nutrient restrictions (unless they have a secondary diagnosis), and therefore, hay soaking is not necessary. Wetting the hay will have a minimal impact on leaching of essential nutrients.          

Bottom line, hay soaking should only be done if the horse has been diagnosed with laminitis, EMS, PSSM, and/or HYPP, and a hay analysis indicates specific nutrients are in excess of recommendations. Thoroughly wetting the hay is necessary for horses diagnosed with respiratory disease. Soaking hay in water is not necessary for healthy horses. For more information on hay soaking, click here.

 By: Krishona Martinson, PhD, University of Minnesota



Monday, March 30, 2015

Grazing Alfalfa

Question: I just bought a farm and the pasture has had grass and alfalfa in it for the past 10 years. Should I be concerned about grazing the alfalfa? I’ve heard horses should not graze alfalfa. 

Response: Horses can graze alfalfa. However, the major issue with pasturing horses in a mixed alfalfa grass pasture is the possibility of excessive weight gain. Even an all grass pasture can have excessive energy for adult horses at maintenance and light work, adding in alfalfa provides even more energy. 

As with any pasture, introduce horses slowly and delay grazing until forages reach 6 to 8” in height to optimize both the health of the horses and pasture. When pastures reach 6 to 8”, begin grazing for 15 minutes, increasing the grazing time each day by 15 minutes until 4 to 5 hours of consecutive grazing is reached. After that, unrestricted or continuous grazing can resume.
Alfalfa is not as tolerant to frequent grazing and mowing compared to cool-season grasses (i..e orchardgrass, bromegrass, bluegrass). It is likely that over time and with good pasture management, the alfalfa will continue to thin and the grasses will continue to thicken.
There are a few things you can do to if your horse(s) start gaining weight. Keep an eye on body condition score. Adult horse body condition score should not exceed 6 (out of the 9 point Henneke scale). If horses start putting on excessive body weight, use a grazing muzzle or restrict grazing to 6 to 8 hours a day (without feeding additional hay).

Finally, if any of your horses are hard keepers or have elevated nutritional needs, the mixed grass-alfalfa pasture will be ideal.

By:  Krishona Martinson, PhD, University of Minnesota 


Certified hay

Question: What is certified hay and how do you raise it?

Response: The invasion of noxious weeds causes substantial economic loss and ecological damage. Common sources for the introduction and spread of weed seed include the transportation and utilization of contaminated forages.

In Minnesota, the state agency in charge of certified hay is the MN Crop Improvement Association (MCIA). The Noxious Weed Seed Free Forage certification program is designed to assure that forage (hay, cubes and pellets) meets minimum standards designed to limit the spread of noxious weeds. Most public lands in the western U.S. require that hay transported into these areas be certified noxious weed free.

To grow Noxious Weed Seed Free Forage, famers must first submit an application for membership to MCIA and apply for field inspection stating the location of the field and expected harvest date. MCIA then inspects the field and intended storage site to determine conformance to standards for freedom from noxious and undesirable weeds. The farmer then harvests the eligible crop and submits a tag request for the bales harvested. Certification labels are then issued by MCIA for eligible bales. The labels must be attached to each bale prior to delivery.

 The MCIA website has additional information at, or they can be contacted by phone at 1-800-510-MCIA.

By:  Krishona Martinson, PhD, University of Minnesota



Fodder for Horses

Question: This year, hay has been difficult to find and is more expense than in past years. We are considering putting in a fodder system to feed our 30 draft horses. We were wondering if you had any information on this system. 

 Response: Hydroponically grown forage (or fodder) has become a new hot topic among livestock producers. There are several companies that are aggressively marketing these systems. With hydroponics, plants can be grown in a small amount of water on a mat with added nutrients, but without soil.

With hydroponics, forage is grown in a greenhouse and growth is usually fast. Harvesting can occur in as little as 7 to 10 days. Hydroponic growing systems have been specifically developed to sprout small grains and legumes, with most systems using barley. When the forage is grown, producers simply roll it up like a roll of sod (sprouted grass and roots) and feed it to livestock.

Many experts do not believe that hydroponically grown fodder is economical, especially if labor is figured into the total cost. Livestock owners should consider the following, the cost of the system to grow about 1,000 pounds of feed per day is over $45,000. This amount is what is needed to supply 36 pounds of dry matter to a herd of about 30 draft horses (assuming an 1,800 pound draft horse fed 2% of their bodyweight). The system is also labor and time intensive. Producers must consider the seed, disposable equipment, facility, fertilizer, heat, light, depreciation, and labor cost when decided whether to grow fodder.    

From the composition of the end product, it appears that little additional tonnage is added from growth of the small grain. The final dry weight is about the same as the grain seed weight. In some cases, dry matter is actually lost due to the respiration occurring during the early germination process. Many experts are concerned that the production of fodder adds nothing more than water, and that the nutrient and mineral content of the fodder (on a dry matter basis) is about the same as the barley seed used. The final fodder product is essentially a concentrate, not a forage due to the low amount of fiber. Therefore, additional forage would have to be fed to meet the fiber needs of horses and other livestock. Finally, fodder is about 90% water, so a significant amount will need to be fed to meet the horses dry matter requirement. 

Since a greenhouse, or similar structure, will be needed to produce fodder, there will likely be a learning curve in producing it. Producers are not likely to start with optimal production yields which can top 1,000 pound daily. Several conditions including outside air temperature (i.e. too hot or too cold) may reduce inside growth. When calculating the potential productivity of a fodder system, the local weather conditions must be taken into consideration. 

Even with high current hay prices, the most economical forage for livestock owners in the Midwest is legume and grass pasture and hay. This is true even in a drought year, and certainly in years when hay prices are more moderate. To help ride out high hay prices, have a good working relationship with a hay supplier to ensure a consistent and reliable source of hay; consider adding hay storage to reduce the effects of price and seasonal fluctuations; buy hay early, do not wait until later summer or fall; and finally, try and budget for the price increase. 

 By: Dan Undersander, PhD, University of Wisconsin and Krishona Martinson, PhD, University of Minnesota


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