Limiting Amino Acids
Most horse owners can quickly tell you the crude protein level in the feed they are giving their horses. But, what horse owners really need to know about, is the amino acid content. Protein is made up of amino acids – similar to how a chain is made up of links. There are two basic categories of amino acids: essential and non-essential. Essential amino acids must be provided in the diet, as the horse cannot manufacture them on their own in the digestive tract, where the non-essential amino acids can be manufactured.
There is another key thing to know when it comes to amino acids – there are “limiting” amino acids. This means that if a horse runs out of a “limiting” amino acid, it can’t utilize any of the remaining amino acids present in the feed. If the horse has enough of the first most limiting amino acid, but then runs out of the second most limiting amino acid, it can’t use the remaining amount of the third most limiting, and so on.
In horses, the first three most limiting amino acids, in order, are lysine, methionine, and threonine. Generally speaking, if these three amino acids are present in sufficient quantities, the ingredients used to provide them also provide the remaining amino acids in sufficient quantities. It is becoming increasingly common to see these three listed on the guaranteed analysis of horse feed tags, as it is an indication of the quality of the protein sources and the balanced nature of the feed.
We hear often from people that “My pony is so fat!” It is often followed with, “He doesn’t need to be fed anything – he so much as sees a bag of feed and he gains weight.”
Obesity in horses can lead to laminitis, overheating and numerous other health issues. Ideally, chubby horses should have their nutrition monitored closely. Three good practices to manage these types of easy keepers are:
- Limit their forage first and provide a controlled-calorie horse feed to complete the missing nutrients from the forage. This still allows the horse or pony to feel as though it gets fed, too.
- If monitored well, grazing muzzles work for overweight horses on pastures, allowing them only small bites of grass but maintaining free access to run with the other horses.
- Not surprisingly, most effective is daily exercise. Increasing the amount of calories burned each day reduces the amount that are stored away as fat.
Taking weight off of an easy keeper is no small task, but is well worth it in the long run. Keeping our equine friends fit will help ensure they stay with us for years to come.
We all know that next to water, forage is the most important part of a horse’s diet. Without it they just can’t survive.
With the high prices of forage there are a few ways you can get a little more out of the forage you feed.
- Start by selecting the best quality hay your budget will allow – higher quality means more nutrition in every bite.
- If practical, weigh out the appropriate amount of hay your horse should eat at each feeding so that the excess isn’t wasted. On average, a horse should eat between 1.5-2% of his body weight in forage per day.
- You may also choose a feed that contains yeast cultures (prebiotics) and direct fed microbials (probiotics) like Lactobacillus Acidophilus. These elements will help your horse’s hind gut better digest and utilize the forage it takes in.
- If your horse is on pasture, a good practice may be to divide your pasture into sections and rotate sections on a frequent basis to allow for maximization of forage produced.
- If hay or pasture is in truly short supply, try utilizing a hay extender product. While it is always beneficial to keep at least some long-stemmed roughage in the diet, using a hay extender can make the few bales of hay you have last quite a bit longer.
Last week a horse owner contacted me about changing her horses diet. She stated that they are ¾ of the way through show season and he is just “off his game”. It seems that the horse was showing a lack of appetite and not finishing his grain. In addition, his disposition seemed to have changed, being rather grumpy and his performance level was suffering. A few times he had shown signs of mild colic over the past two months.
I suggested the owner contact her veterinarian, as it sounded like the horse may have an ulcer. I explained that the percentage of horses with ulcers continues to increase, and that higher intensity levels of training are correlated with an increase in ulcer incidence. The ulcers often occur in the upper third of the stomach, which does not have a mucus layer and does not secrete bicarbonate that helps to buffer stomach acid. It is also interesting to note that ulcers have not been founded on pastured horses. This is likely due to the fact that as a horse grazes, it produces large amounts of saliva, which contain the bicarbonate and amylase needed to provide a buffer for the stomach lining.
The owner was not pleased with my answer, but agreed to call the vet. Within the week she contacted me and said the horse had been diagnosed with a gastric ulcer. He was now on medication, but we needed to make dietary changes as well. I suggested the following “back to basic” steps to help manage her horses condition:
- Allow the horse to be turned out or hand grazed.
- If access to pasture is not possible, good quality hay is a must. Recent studies indicate that legume hay is an excellent choice, possibly due to the high calcium content which may help to serve as a buffer.
- Breaking the daily rations into smaller more frequent meals also help keep saliva production constant and protect the stomach lining – more like “grazers” instead of “meal eaters”.
- High starch diets also tend to aggravate ulcers due to increased acid production. A high fat high fiber feed is ideal.
In essence, to help keep them from suffering the ill effects of ulcers, we need to let our horses just be horses.