can be a beautiful time of year for horseback riding. However, frost can
negatively impact horse health during fall grazing.
There are no reports of toxicity of
horses grazing frost damaged pastures (includes grass and legume species).
However, frost damaged pastures can have higher concentrations of nonstructural
carbohydrates, leading to an increase in potential for founder and colic,
especially in horses diagnosed with or prone to obesity, laminitis and Equine
Metabolic Syndrome. To help prevent these health issues, wait up to a week
before turning horses back onto a pasture after a killing frost. Subsequent
frosts are not a concern as the pasture plants were killed during the ﬁrst
Why do nonstructural carbohydrates increase during the fall? During
the day, plants carry out the process of photosynthesis. In this process, they
make carbohydrates as an energy source for the plant. A second process,
respiration, is carried out when the plants use up the carbohydrates they
produce during the night for energy. Plant respiration slows down when
temperatures are near freezing. As a result, the plants hold their
carbohydrates overnight. Freezing can stop respiration and lock the
carbohydrates in the plant for over a week. Thus, plants tend to contain more carbohydrates
in colder temperatures or after a frost. Often, horses will prefer forages
after a frost due to the higher carbohydrates levels.
For more information on fall health concerns for grazing horses, click here.
Question: I put a grazing muzzle on my fat gelding. He is ridden multiple times a week, but is an easy keeper. He shares 8 acres of pasture with one other horse. Should I leave the grazing muzzle on all the time or give him an hour of freedom without the grazing muzzle each day?
Answer: We know from past research that a grazing muzzle reduces intake by 30% and that some horses can become very adept at grazing through a muzzle. As long as the horse can easily access water and can tolerate wearing the muzzle, we recommend leaving the muzzle on all day for an overweight horse with access to pasture. A 30% reduction is calories (or pasture) should result in weight loss. Research has also shown that horses with access to as little as 3 hours of pasture each day can consume a majority of their daily calories and can anticipate and adjust to the restricted grazing schedule.
Owners should track their horse’s bodyweight and body condition score each month. Reduce the amount of time the horse is muzzled if excessive bodyweight and body condition is lost. Conversely, if the horse starts to gain bodyweight (or is not losing bodyweight), it might be best to house the horse in a drylot and feed a reduced calorie hay diet (i.e. mature grass hay). The goal should be for the horse to lose weight slowly but steadily. If excessive bodyweight continues to plague the horse, we recommend working with an equine nutritionist and your veterinarian to identify additional solutions for weight loss.
Question: My two horses tested high in their fecal egg counts; I dewormed them regularly. We had a mild winter and they were still foraging on the pasture. I am wondering if I am managing their manure badly? We drag the manure piles in the pasture, but are we spreading out the parasite eggs and making it worse?
Answer: Good pasture management can help reduce parasites, especially stronglyes. Strongyle larvae develop within the manure pile, migrate onto pasture forages during wet weather and wait to be ingested by horses. Rotational grazing, avoiding overgrazing and ideal stocking rate can help to reduce strongyles. We recommend initiating grazing when pasture grasses are between 6 to 8” tall and rotating horses to a new pasture (or a drylot) when most of the forage has been grazed down to 3 to 4” tall. A pasture where most of the forage is below 3” tall is considered over‐grazed. This is especially important when managing strongyles as larvae tend to inhabit the lower part of forage plants. Allowing your horses to graze a pasture during the winter months (when forage re‐growth is not possible) may have resulted in over‐grazing and ingestion of parasite eggs. We recommend a stocking rate of 2 acres of pasture per adult horse. If the pasture is well managed, this should result in not needing to supplement hay during the grazing season. Parasite populations tend to be greater if the pasture stocking rates are higher (less than 2 acres per horse), especially in over‐grazed pastures. Since you have two horses, ideally you would have at least 4 acres of pasture.
Dragging is a recommend pasture management activity. Dragging is necessary to disperse manure piles since horses will rarely graze near these areas. However, to help reduce the parasite load, dragging should be reserved for hot and dry periods of the summer. A few weeks of high temperatures and limited rainfall after dragging will help kill strongyle larvae. During this time, it’s important to remove the horses from the pasture. During wet periods, horse owners should remove the manure from the pasture weekly, if possible. This may not be practical in all situations, but may be necessary in high‐risk scenarios.
We suggest you continue to work with your veterinarian and use your fecal egg count results to strategically deworm your horses. Implementing a rotational grazing program, avoiding overgrazing, dragging manure piles during hot and dry periods and confining your horses to the drylot during the winter months should also help reduce the parasite load in your pasture and horses.
Question: I’ve heard conflicting recommendations on when to start grazing my horses. Is April 1st too early to start grazing? Answer: Spring grazing should be introduced slowly and delayed until grasses reach 6 to 8″ to optimize both the health of the horse and pasture. Calendar date is not important as weather conditions and grass growth can very greatly from year to year.
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.
We also recommend feeding horses their normal hay diet before turning them out to pasture during the first several grazing events of the year. This strategy should help avoid rapid intake of pasture grasses.
Even though hay and pasture are both forms of forages, there are significant differences. A gradual change from one feedstuff to another provides enough time for the microbial populations to adjust, reducing the chance of colic and laminitis.
As a horse owner, I have come to realize that horses have an uncanny ability to get themselves into trouble. Whether it be messing with the fence, making play-things of their stall or breaking into the feed room to grab an extra snack, if we don’t want them to get into it, horses seem to find a way to get into it! If lucky, the vet doesn’t need to be called, but there is usually some upgrading of hardware, the perpetual fixing of the fence or continuously beefing up security around the feed room. But what about the things that we as humans haven’t built? What naturally occurring perils of danger will my horse find and get himself in to?
As Winter fades and Spring makes a welcome entrance, thoughts turn from feeding hay to blissfully sunny pasture turnout. Now is a great time to educate yourself about plants that can harm your horse.
March is poison prevention month and as horse owners, knowing what plants are poisonous to your horse can go a long way in preventing trouble. To help get you started, here is a good resource of information about poisonous plants that grow in the Midwest, from the University of Minnesota Equine Extension Office.
If you find plants of poisonous varieties where your horse can access them, please work with your local extension office on methods of controlling exposure. Also remember to check your garden and landscaping as many plants listed are popular decorations.
It is also important to note that plant variety growth varies by geographic region so be sure to check with your local extension office for information specific to the area in which you live.
So while you may not be able to keep them from breaking the fence, breaking into the feed room (despite the keypad lock on the door) or dismantling the components of their stall, you can be aware of and have a plan to manage the poisonous plants that dare grow near your horse.