Understanding Alfalfa Hay Protein Content and its Factors

Alfalfa hay is a popular forage crop known for its high nutritional value, particularly its protein content. Protein is an essential component of a balanced diet for livestock, making alfalfa hay a valuable feed option for many farmers and ranchers. In this article, we will explore the protein content of alfalfa hay and discuss the factors that can affect it.

Alfalfa Hay Protein Content

Alfalfa hay is known for its high protein content, which is one of the reasons why it is widely used as a feed for livestock. On average, alfalfa hay contains around 15-20% crude protein. This means that for every pound of alfalfa hay, you can expect to find approximately 0.15-0.20 pounds of protein.

The protein content of alfalfa hay can vary depending on various factors, including the stage of maturity at harvest, environmental conditions, and the variety of alfalfa. Let’s take a closer look at these factors.

Factors Affecting Alfalfa Hay Protein Content

1. Stage of Maturity

The stage of maturity at which alfalfa is harvested plays a significant role in its protein content. Generally, younger alfalfa plants have higher protein content compared to more mature plants. This is because as the plant grows, it allocates more energy towards stem and leaf development, resulting in a decrease in protein content.

Therefore, if high protein content is a priority, it is recommended to harvest alfalfa at an early stage of maturity, typically when the plants are in the bud or early flowering stage.

2. Environmental Conditions

The environmental conditions in which alfalfa is grown can also impact its protein content. Adequate sunlight, water, and nutrient availability are essential for optimal protein synthesis in plants. Insufficient sunlight or water, as well as nutrient deficiencies, can result in lower protein content in alfalfa hay.

Additionally, extreme weather conditions such as drought or excessive rainfall can also negatively affect protein synthesis in plants, leading to lower protein content in the harvested hay.

3. Variety of Alfalfa

There are different varieties of alfalfa available, and each may have variations in protein content. Some varieties are bred specifically for high protein content, while others may prioritize other traits such as yield or disease resistance. Therefore, the choice of alfalfa variety can influence the protein content of the harvested hay.

Profile of Protein in Alfalfa Hay

The protein in alfalfa hay is a combination of various amino acids, the building blocks of proteins. Alfalfa hay is particularly rich in essential amino acids, which are the ones that cannot be synthesized by the animal’s body and must be obtained through the diet.

The protein profile of alfalfa hay includes amino acids such as lysine, methionine, and histidine, which are important for animal growth and development. These amino acids contribute to the overall nutritional value of alfalfa hay as a feed source.

It is worth noting that the protein content of alfalfa hay can vary slightly depending on factors like storage conditions and processing methods. However, these variations are generally minimal and do not significantly impact the overall protein content of the hay.

List of Amino Acids in Alfalfa

Here is a list of some of the amino acids found in alfalfa hay:

  1. Arginine
  2. Cystine
  3. Histidine
  4. Isoleucine
  5. Leucine
  6. Lysine
  7. Methionine
  8. Phenylalanine
  9. Threonine
  10. Tryptophan
  11. Tyrosine
  12. Valine


Alfalfa hay is a valuable source of protein for livestock, with an average protein content of around 15-20%. Understanding the factors that affect protein content, such as the stage of maturity, environmental conditions, and the variety of alfalfa, can help farmers and ranchers make informed decisions when it comes to selecting and harvesting alfalfa hay.

By considering these factors and ensuring optimal growing conditions, farmers can maximize the protein content of their alfalfa hay, providing their animals with a nutritious and balanced diet.