Amino acids are the building blocks of protein and a major part of building muscle and tissue. They also play a pivotal role in other metabolic processes in the cells. There are two groups of 22 types of amino acids, 14 of which are non-essential for dogs. These non-essential amino acids are produced by your dog’s body and are thus not required in your dog’s diet. The eight remaining amino acids are essential because they cannot be manufactured by your dog’s body and are thus gained only from their diet.
Most dog owners usually focus on protein when deciding which food to give their dogs, and for good reason, as protein is essential in the balanced diet of a dog. Most commercial foods should contain at least 20% protein, which is usually indicated on the packaging. However, this does not tell you whether the required amino acids are present in the protein. This is important because your dog’s body breaks down this protein into amino acids and uses them as needed.
In this article, we look at the eight amino acids that are essential to your dog’s health and how you can make sure they get them.
Essential and non-essential amino acids
Non-essential amino acids are defined as amino acids that can be produced endogenously from available nitrogen and carbon sources within your dog’s body, and thus, your dog does not need them in their diet. The following, however, are the amino acids that are vital to your dog’s health and that they must get from their diet.
Arginine is a basic amino acid present in most proteins. It is a vital part of immune function and in inflammation reduction, and it is also important in regulating blood flow. It stimulates the release of hormones such as insulin and gastrin. Arginine is found in sufficient amounts in most animal sources and plant proteins like legumes and grains.
Histidine plays an important role in oxygen exchange in your dog’s lungs and other tissues and can also play a large role in immune function. A deficiency of histidine can cause weight loss, lethargy, and decreased appetite. It is found in sufficient amounts in most plant and animal proteins, including muscle meat and eggs.
3. Isoleucine, Leucine, and Valine
Branched-chain amino acids isoleucine, leucine, and valine are all influential in protein synthesis and essential to muscle deposition. Dogs that are deficient in these branched-chain amino acids will swiftly lose their appetite and experience weight loss, and it may even result in liver disease.
Lysine plays an important role in energy metabolism, DNA replication, and regulating cellular metabolism. Sufficient amounts of this amino acid are found in most animal proteins, including eggs and dairy, and less so in grains and legumes.
5. Methionine and Cysteine
Methionine and cysteine are sulfur-containing amino acids, and cysteine is synthesized in your dog’s body from methionine. Both these amino acids are essential for normal growth and help regulate several cellular replication processes. Deficiency in these amino acids can result in weight loss, decreased appetite, and possible dermatitis.
This amino acid is essential to the normal growth of muscle tissue and hormone regulation, and it is converted into tyrosine in your dog’s body. It is also the precursor to melanin in your dog’s hair, and twice the amount is required in dogs with black coats. Deficiency can result in a reddening of your dog’s coat, weight loss, and decreased appetite.
Threonine is a necessary amino acid for the building of protein in dogs and helps control normal physiological functions, like insulin release. A deficiency in this amino acid can result in weight loss and decreased appetite. It is found in sufficient amounts in animal proteins, as well as legumes and grains.
Tryptophan is required for normal growth in dogs and is the precursor to niacin, serotonin (a neurotransmitter), and melatonin (a hormone). It also has calming effects on your dog and may even cause a lessening of aggressive and overly excitable behavior when used in supplements.
Can dogs eat too much protein (or too little)?
Now that you know all the essential amino acids that your dog requires in their diet, which are ideally sourced from animal proteins, can they have too much of a good thing? Dogs are not carnivores, and while they require good-quality protein in their diet, too much can certainly cause health problems. Dogs can only use a certain percentage of the protein that they ingest, and the rest must be broken down for energy or stored as fat. All the byproducts of this protein breakdown are processed by the liver, and too much protein can cause your dog’s liver to work much harder. High amounts of protein can also result in obesity in your dog and even blood issues like hyperkalemia.
Too little protein in your dog’s diet can also cause serious health problems, depending on how low you go. The health effects can range from dry and coarse coats, low energy, and skin issues to more serious conditions, like compromised bone and muscle development. Anything under 20% is considered a low-protein diet.
Plant vs animal protein sources
All essential amino acids can be found in plants, like grains and legumes, but are these adequate replacements for animal-based proteins? In short, no, because animal-sourced proteins are considered “complete” proteins. The amino acids are provided to your dog in the perfect ratios and are highly digestible, making them easily absorbable. But this does not mean plant-based proteins do not have their place, and they are important in your pooches’ diet too.
While most of the essential amino acids that your dog needs will not be listed on the ingredients list of their food, if your dog is eating a well-balanced diet with plenty of animal proteins, you can usually be sure they are getting all the amino acids that they require. Simply judging your dog’s food by protein content alone can be misleading because this includes plant protein too. The right amount of quality animal protein will usually ensure that your pooch is getting a good variety of amino acids.
Good-quality dog food will usually have an Association of American Feed Control Officials endorsement on the label, ensuring that the food has the correct ratio of amino acids. This label, along with plenty of animal proteins, will ensure that your pooch is getting all the essential amino acids that they require for a happy and healthy life.
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