Equine Nutrition/Proteins

Proteins

The following information was taken from https://class.coursera.org/equinenutrition-001/wiki/view?page=Week2 Equine Nutrition by Jo-Anne Murray

Protein • Required for various functions

 – Structural (e.g. muscle, skin, hair)
 – Enzymes (catalysts that affect the rate of reactions in the body)
 – Hormones (chemical messengers that regulate metabolic processes)
 – Immune compounds (for fighting infection)
 – Transport compounds (e.g. transport of nutrients)

• Consists of chains of amino acids

• Essential and non‐essential amino acids

• Non‐essential Protein: synthesized by the animal

• Essential Protein(need to be supplied in the diet)

 – Lysine (first limiting: present in the least amount relative to requirement)
 – Methionine
 – Threonine
 – Isoleucine
 – Valine
 – Arginine
 – Tryptophan
 – Histidine
 – Phenylalanine

• Protein breakdown begins in the stomach

 – Acidity denatures the proteins
 – Pepsin partially degrades proteins into smaller peptides
 – No protein absorption in the stomach

• Further broken down in Small Intestine

 – Proteases break down proteins to amino acids
 – Absorbed across Small Intestine gut wall

• Protein associated with the plant cell wall – fermented in Large Intestine

• Protein digested in Small Intestine – used by the horse

• No amino acid absorption in Large Intestine

• Microbes in Large Intestine degrade protein

 – Used for microbial growth
 – No biological value to horse