Basic Nutrients Flashcards
What are the 6 key nutrient groups?
-water
-protein
-carbohydrates
-fats
-minerals
-vitamins
How much of body weight is made up of water?
70%
What are the functions of water?
-transport medium
-temperature regulation (sweat/panting)
-digestion (facilitates hydrolysis)
-lubricant for body tissues
-facilitates the elimination of toxins from the body via the kidney
How does water contribute to temperature regulation?
-it transports the heat away from internal organs
-redirecting blood to the superficial veins to transfer heat to the skin
-evaporation of water from the skin
What is the bodies water requirements?
50ml/kg/day
What are sources of water?
-ingested water
(drinking/food)
-metabolic water
(produced in body by oxidation of protein, fat and carbohydrates)
How can water exit the body?
-urination
-faeces
-vomiting
-saliva
-sweat
-bleeding
-lactation
What are the signs an animal in a water deficit displays?
-skin tenting
-tacky mucous membranes
-sunken eyes
-urination ceases or decreases
-urinalysis and blood sample results
What is the normal urination output for cats and dogs?
1-2ml/kg/hr
24-48ml/kg/day
What advice can be given to cat owners to encourage consumption?
-change position of food bowls
-flowing water
-wet food
-offering more bowls
-type of bowl
What advice can be given to dog owners to encourage consumption?
-soaking kibble
-wet foods
-change height or type of bowl
-portable bowl for walks
-flavoured waters
-ice cubes
What is the structure of proteins, what are they made of?
-complex organic compounds
-large molecules that are composed of long chains of amino acids
-made up of carbon, hydrogen and oxygen
Where are non essential amino acids produced?
In the body
Where are essential proteins supplied from?
Supplied in the diet as they cannot be synthesised within the body
What are the 10 essential amino acids?
-arginine (required in cats)
-histidine
-isoleucine
-leucine
-lysine
-methionine
-threonine
-tryptophan
-valine
-taurine (only in cats)
Why is arginine required in cats?
-prevents ammonia accumulating in the blood
-required by the body in order to metabolise nitrogen compounds, without it ammonia can accumulate in the blood
Why do cats require taurine in their diet?
-they cannot synthesise enough taurine to meet their needs
-lack of taurine during gestation can cause foetal resorption, low birth weight of kittens, poor survival rates and reduced growth rates
What is biological value?
-refers to the quality
-graded acceptable, digestible and utilisable
Do high biological value proteins have high or low proportions of essential amino acids?
-usually have high proportions of essential amino acids within them
-they closely resemble the requirements of the animal
What are the characteristics of high biological value proteins?
-highly digestible
-leave fewer waste products to be excreted from the body
What are sources of protein?
-egg
-fish
-milk
-chicken
-liver
-rice and oats
What are the functions of proteins?
-growth
-pregnancy and lactation
-repair of damaged tissues
-dietary source of energy
-regulation of metabolism
-provides strength with flexibility in ligaments, tendons and cartilage
-transport and storage of oxygen in the muscles
-transport of other nutrients
-protection of body against infections
What are relative requirements based on?
-species
(cats have higher requirements than dogs)
-lifestage
-reproductive status (pregnant or lactating)
-pathophysiological state (cancer, trauma, burns)
-workload
What are the signs of excess protein in the body?
-overweight
-contributes to progression of some clinical conditions
(liver or kidney failure as these organs have to work harder to eliminate protein from their system)
What can cause an excess in protein?
-over feeding
-under feeding
-feeding an inappropriate diet
-disease
What are the signs of a deficiency in protein?
-weight loss
-poor skin or hair
-anaemia
-increased susceptibility to disease
What can cause a deficiency in protein?
-inadequate food intake
-poor quality dietary proteins
-high fibre or low energy diets
-inability to digest or absorb proteins
-excess protein loss
-illness
How are proteins digested (broken down)?
-mouth is where mechanical digestion starts
-stomach where mechanical/chemical breakdown continues
-protein broken down into polypeptides by the enzyme pepsin
-small intestine produces trypsin which breaks down peptides into amino acids
How is protein absorbed in the body?
-absorbed through the intestinal wall into the blood
-blood flows from the small intestine to the liver via the hepatic portal vein
How are proteins utilised in the body?
-tissue proteins
-enzymes
-albumin
-hormones
-surplus used as energy
What are carbohydrates made up of?
-carbon
-hydrogen
-oxygen
What are the 3 main groups of carbohydrates?
-simple sugars
-oligosaccharides
-polysaccharides
What are simple sugars?
-monosaccharides such as glucose
-disaccharides such as lactose
What are oligosaccharides?
-short chains of monosaccharides
-can be hydrolyses to simple sugars
-act more like dietary fibre
What are polysaccharides?
-includes starches and fibre
-large and complex molecules composed of many monosaccharide units and may be bonded
What are sources of carbohydrates?
Sugars
=fruit
Lactose
=milk and dairy products
Starches
=potatoes, rice, grains, wheat
What are the functions of carbohydrates?
-includes energy, produces heat and produces lactose in lactation
-promotes and regulates bowel function
-helps maintain health of the colon
-not essential within the diet
What are the relative requirements of carbohydrates in the diet?
-dogs and cats have no absolute requirements for carbohydrates in their diet
-are an easily digestible source of energy
What % of carbohydrates are normally seen in cats and dogs diet?
Dogs
30-60% in dry diets
Cats
Up to 35% on a dry matter basis
How does mechanical digestion begin to break down carbohydrates?
-chewing in the mouth
-chemical = ptyalin secreted by the parotid gland begins breaking down some carbohydrates
How does enzymatic digestion continue to break down carbohydrates?
-stomach is where mechanic digestion continues
-small intestine is where the enzyme amylase breaks down carbohydrates converting them to starch and then to maltose
Where is glucose absorbed and stored?
-absorbed into the blood stream
-carried via the hepatic portal vein to the liver
-store in liver
-glycogen is released into the circulation as required for energy
How does microbial digestion aid in the breakdown of carbohydrates?
-large intestine is where intestinal microbes (bacteria) produces enzymes
-where fibre is digested
How do carbohydrates undergo fermentation?
-carbohydrates broken down in an environment with little or no oxygen in such a way as to release energy
-microbes in the large intestine are anaerobes (no oxygen)
How are carbohydrates utilised when broken down into microbes?
-only use part of the energy they release
-rest of the energy benefits the mucosal lining of the large intestine
What are fats made up of?
-triglycerides
-where each triglyceride is a combination of 3 fatty acids joined by a unit of glycerol
What are the 3 essential fatty acids?
Alpha-linolenic acid (omega-3)
Linoleic acid (omega-6)
Arachidonic acid (omega-6 cats)
What is the function of omega-3 fats?
Anti-inflammatory function
Can dogs and cats synthesise arachidonic acid?
Dogs can synthesise
Cats cannot synthesise
-this demonstrates their carnivorous nature
What are functions of fats?
-source of energy
-improves texture of food
-acts as carrier and aids in absorption of fat-soluble vitamins
-aids kidney functions
-essential component of cell membrane
-protects internal organs
-acts as insulation
What can deficiencies in fat lead to?
-poor wound healing
-dry coat
-scaly skin
-alopecia
-pyometra
-reduced reproductive function
What can an excess in fat lead to?
-increase in energy density of the diet
-pancreatitis
How is fat digested in the body?
-begins in mouth with mechanical digestion
-stomach is where enzyme gastric lipase breaks fats into fatty acids and then to glycerol
-small intestines pancreatic juice aids in this process
What is bile salts function in the break down of fats?
-act as detergents
-breaks the surface tension between fats ad water
-so fats are broken down into small droplets making it easier for lipase to reach them and break down the fat
How are fats absorbed?
-absorbed via the lymphatic system
-then the cysterna chyli and thoracic duct where it is carried in the blood stream to the liver
How are fats utilised in the body?
-liver is where fat metabolism takes place
-lipids require by the body are synthesised in the liver
-fatty acids are metabolised to produce energy
