Proteins Flashcards
What is a non-essential amino acid?
An amino acid that can be produced in the body from excesses of others
What is an essential amino acid?
An amino acid that can not be synthesised from excess of other amino acids so must be supplied in the diet
What are protein requirements?
Dogs - 18%
Puppies - 22%
Cats - 26%
Kittens - 30%
Where can protein be sourced from?
Eggs Fish meal milk protein Chicken Rice
What can excess/ deficney be caused by?
Over/under feeding, feeding the wrong diet or disease
What is a common disease that causes protein excess/deficeicny ?
Exocrine pancreatic insufficiency - prevents animals fro digesting food properly
Explain the digestion and absorption of proteins
The stomach breaks down protein into polypeptides with the enzyme pepsin (in the presence of HCl)
In the small intestine polypeptides are broken down into amino acids by enzymes (from lining of small intestine and pancreas)
Amino acids then absorbed through intestinal wall into blood, carried to the liver via the hepatic portal vein.
What are functions of proteins?
- Energy
- Repair (post illness or injury)
- Maintenance of body, skin, hair etc.
- Growth
- Pregnancy
- Lactation
- Regulation of metabolism (enzymes/hormones)
- Structure of cell walls
- Transports other elements
- Immunoglobins
- Proteins in blood
Give examples of essential amino acids
- Arginine
- Histidine
- Isoleucine
- Leucine
- Lysine
- Methione
- Phenylalanine
- Threonine
- Tryptophan
- Valine
- Taurine (cats)
Why is taurine essential in cats?
deficiency can lead to central renal degeneration, as well as stopping the ability to form bile salts. Also affects fertility and the development of kittens in the uterus.
Why is arginine needed?
metabolise nitrogen – a deficiency causes a build-up of ammonia in the blood.
What is protein quality?
Higher biological valued proteins are more digestible and leave fewer waste products needing to be excreted.
Proteins with higher biological value usually have higher proportions of essential amino acids in them.
