You only know how much you really feed if you weigh your roughage.
It’s eight o’clock in the morning, you walk into the stable and start with feeding the horse roughage. You always pick up a flap of hay - just a little more than half a forearm, where the bale naturally falls into ‘slices’. Not very specific amounts when it comes to the most important energy source for your horse. And also not very accurate, so our research reveals. Unknowingly, we often feed far too little.
It has been estimated that 41% of the riding horses in the Netherlands do not receive the MINIMUM amount of roughage of 1% of their body weight. Weigh how much roughage you have to feed using a simple hanging luggage scale. A 500 kilogram horse normally eats 10 kilograms of haylage (minimum 7.5 kg).
For this research, we traced a (stable) owner feeding 250 riding horses at different stables. After the roughage was given, we weighed how much was actually fed. This very simple research gave interesting results. Table 1 provides an overview of the measured minimum, maximum, averages, and the standard deviations of the amounts of roughage given to the horses per day.
How much roughage does a horse need?
Horses need at least one kilogram of dry matter per 100 kilograms of body weight per day, i.e. 1% of dry matter. This is the absolute MINIMUM for a well-functioning gut. The NORMAL roughage uptake of a horse is between 2% and 2.5% of their body weight per day.
Example: Hay contains less water than haylage. That’s why, if the horses diet contains haylage, it is necessary to feed comparatively more haylage than hay to reach the right amount of dry matter roughage. For a 500 kilogram horse, this means that the required amounts are: MINIMUM 1.4% = 7.5 kilograms of haylage per day. NORMAL 2% = 10 kilograms of haylage per day.
How much do we really feed?
Table 4 shows roughage percentages relative to the horse’s body weight, as given to the 250 horses that were included in our study. It can be seen that:
· 41% of the horses receive less than the MINIMUM of 1% dry matter as roughage.
· 75% of the horses received less than 1.5% roughage per day.
· Only 4% of the horses received the NORMAL 2% or more roughage.
The conclusion of this research is that there is a great deal of variation in the amount of that roughage owners feed to their horses, and that most feed too little roughage. All stable owners were surprized to learn that they were feeding too little, they were all under the impression that they were feeding enough roughage. It is clear from this research that you cannot be sure of how much roughage you are giving, unless you measure it (even occasionally).
Boosting roughage intake by eating straw
In the survey, 87.7% of the horses included were stabled with straw as bedding. When horses do not have enough hay or haylage roughage, they compensate their rations by eating straw. We could not measure how much straw they had eaten. Eating too much straw increases the risk of blockages in the esophagus.
Ration requirements for horses
Feed management contributes to the optimal functioning of the digestive system, can prevent nutritional problems, including colic, and ensures that the horse can meet its natural needs, so that animal welfare is not limited. For this, the diet should consist of 60% of roughage. The amount of concentrated feed should be kept to a minimum, whereby the horse stays at a healthy weight, and the ration provides the energy needed for the work to be performed. Concentrate must be limited to 0.75% of the body weight per feed. The total amount of concentrate must be divided over at least three feeds per day at fixed times, so that the feed is distributed throughout the day. This helps to regulate the production of acid in the stomach and the intestines.
To reduce grains and starch as concentrate, alternative energy sources can also be fed to the horse. Examples include corn oil, sugar beet, soy hulls and rice bran. For the optimum functioning of the digestive system and the prevention of adverse effects of concentrates, it is advisable to provide a horse with at least 1.5% roughage of body weight per day. Horses with a roughage based diet eat 2% to 2.5% of their body weight per day. Horses require long fiber roughage for chewing and good functioning of the digestive system.
Lack of roughage
In addition to concentrates, roughage also plays an important role in whether or not some problems develop. A lack of roughage is related to a high risk of developing colic. As the digestive system of a horse is primarily designed for processing roughage, there are significantly fewer problems if the diet consists mainly of roughage. Horses require at least 1% of their body weight of roughage per day for optimal functioning of the digestive system. In addition, it is important for the optimal functioning and the need to chew that horses get long-fiber roughage. The need to chew is related to welfare, because, as mentioned earlier, horses are adapted to continuous eating small portions. Saliva is only produced when the horse chews and this is important for neutralization of stomach acid.
Horses with a diet of roughage alone spend 40% of their time eating and chewing, and stand still 45% of the time. Horses on a diet of concentrates spend only 3% of their time eating and chewing end stand still for 62% of the time. As horses are grazers, health and behavioral problems can occur when they do not have the ability to graze. Behavioral problems are expressed in stereotypical behavior, and are associated with the inability to meet the natural needs, thus limiting the welfare of the horse. Horses on a diet of concentrate have a greater risk of developing stereotyped behaviors, such as crib-biting or wood-chewing. This is because they have the opportunity to eat for a limited part of the day and cannot express the natural behavior, whereby a horse naturally has the opportunity to eat all day long. Chewing wood from trees, fences or barns are associated with a lack of fiber in the food.
Crib-biting in relation to roughage and stomach acid
As described above, horses with a shortage of roughage have a greater risk of developing stereotypic behaviors. The most common stereotypical behavior that is associated with a shortage of roughage is crib-biting or ‘cribbing’. The horse places its incisors on an object and pulls back. No air is absorbed in the stomach, which was initially thought. Air sucking does not exist. This means that crib-biting is probably not the cause of gas colic or decreased appetite, but it is suspected that crib-biting stimulates an increased production of saliva through movements similar to chewing, and that the saliva serves as a buffer for the acid in the stomach.
Acid production in the stomach of a horse is a continuous process. Stomach acid is normally buffered by food and high concentrations of bicarbonate in the saliva that is released during chewing. Horses only salivate by chewing, and as long as a horse receives sufficient roughage, problems do not occur. However, if horses do not receive enough roughage, problems can occur. A horse fed concentrate food rather than roughage doesn’t need to chew as much, and, therefore, produces less saliva.
It has been shown that horses with an unlimited amount of hay as a diet have significantly less stomach acidification. The production of stomach acid is higher when eating concentrates than when eating roughage. Due to tcrib-biting, horses have a more constant production of saliva. The connection between crib-biting and saliva production is not yet confirmed.
Horses that crib-bite spend 15 to 20% of the day on crib-biting and the frequency of crib-bites increases considerably at the time of feeding concentrate. As there are even more physiological and behavioral aspects to crib-biting, the increased saliva production may only be a by-product. Endorphins are released during crib-biting that allow the horse to relax. It is seen as a coping mechanism to relieve stress and through this, it is possible for the horse to adapt to the environment.
Crib-biting is often associated with colic and osteoarthritis of the temporomandibular joint. A link between stomach ulcers and crib-biting has not yet been demonstrated. Damage to the gastric mucosa is associated with teeth-grinding and behaviors that indicate colic.
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