Digestive system and animal nutrtion Flashcards
Balanced diet
Contains carbohydrates, protein, fat, vitamins, minerals and water
Lactating animal
A female animal that is producing milk
Macrominerals
Are required in large amounts in the animal’s diet. Calcium, phosphorus and magnesium are examples.
Microminerals
Are required in trace amounts. Iron and cobalt are examples.
Water
Essential for growth, digestion, reproduction, transport of nutrients in the body, lactation and elimination of waste products. Aids in temperature
regulation and involved in many metabolic processes.
Metabolic processes
Collectively a group of chemical reactions e.g. aerobic respiration, that occurs in an animal’s body.
Dry animal
A cow or another animal that is no longer producing milk.
Monogastric animal
An animal with a single compartment stomach, compared with a ruminant
which has a four chamber stomach, ex. Pigs, horses and humans.
One stomach chamber, cannot digest cellulose, no regurgitation, no fermentation of food.
Produces gastric juices which contain enzymes that breakdown proteins and acids (pH 2) to aid in chemical digestion of food.
Essential amino acids
Amino acids that cannot be manufactured in a monogastric animal’s body and
must be obtained in the diet. E.g. lysine and methionine.
Non-essential amino acids
Amino acids that can be manufactured in the body from other amino acids.
E.g. alanine and glutamine
Deficiency
A lack or shortage of a substance in an animal’s diet.
Mineral bullet
A large pill used to provide a consistent supple of micronutrients to cattle or sheep.
Gross energy
The total energy contained in any feed.
Digestible energy
Is the gross energy minus the amount of energy egested in the faeces.
Metabolisable energy
Is the digestible energy minus the energy lost in the form of methane gas and urine.
Net energy
Is the amount of energy available for use by the animals after subtracting heat lost during digestion and other metabolic processes in the animal’s body.
Maintenance diet
The amount of feed that allows an animal to maintain a good health condition with no loss or gain in weight.
Production diet
The extra amount of feed required to produce 1kg of LWG, 1L of milk, and 1kg of wool or to produce a calf or a lamb. Animals on a production diet must be provided with feed that is more than their maintenance requirements.
Colostrum
The first milk secreted by mammals after giving birth. It is high in nutrients and antibodies and is essential for the survival of the new-born animal.
Bulky feeds
Are high in water or fibre but low in energy. E.g. grass, silage, hay, haylage and kale.
- Acidosis occurs when lack of fibre
Concentrates
Are feeds that are low in water and fibre but high in energy. E.g. cereals, fats, oils, molasses, beet pulp and feed supplements
Advantages of formulated concentration ration
- high energy & carbohydrates
-Seed coat contains fibre
- Can be used to supplement poor quality silage
- Ensures production targets are met easier
Steaming up
The practice of increasing the amount of concentrates being fed to sheep in late gestation in order to prevent twin lamb disease. This ensures a healthy lamb and promotes good milk production.
Co-Enzyme
A compound that binds to an enzyme to catalyse a reaction
More protein is required for
- Young animals (for growth & muscle development)
- Lactating animals ( for milk production)
- Animals in late gestation (Offspring development)
Why do ruminant animals not have essential amino acids
Because microorganisms in the rumen synthesise amino acids
Supplementing diets
- dusting mineral supplement onto silage ( Cal Mag)
- Providing mineral licks
- Dressing the pasture
- Adding into drinking water
- Oral dose
Crude Protein
Refers to % of protein in a feed (not over 18%) eg soybean
Dry matter
What’s left when all water is removed
Concentrates additives
- cereal grains - roll&grind to aid digestibility
- Molasses/beet pulp - palatable, nutrias but low in fibre
- Soya bean meal - high in protein
- Maize gluten - source of fibre
Ration formulation
Requirements vary on : age ,sex ,health, and level of production
formulated on
what ingredients contain
how much animal will eat
what animal requires
Incisors
Chisel like teeth used for cutting and biting.
Canines
Pointed sharp teeth used for tearing food
Dental formula of pig
I: 3/3
C: 1/1
P: 4/4
M: 3/3
Dental formula of cow/sheep - ruminant
I: 0/3
C: 0/1
P: 3/3
M:3/3
Horny pad- Meets lower incisors and canine to chop grass
Diastema - stores ingested materials while chewing
Chewing the cud
Rumination. Food is rechewed for a second time before being swallowed again.
Rumen
Contains microorganisms (bacteria/fungi) which have a symbiotic relationship with the ruminant animal.
The microbes (bacteria & protozoans) break down cellulose in plant cell walls.
Anaerobic conditions with pH of 6.5 - 7.2
The rumen contracts to force these gases out of the rumen but if gases are not expelled, they cause bloat.
Reticulum
Food moves from the rumen into the reticulum
Animal can spend 3-6 hours ruminating per day depending on how fibrous the food is
Involved in rumination – chewing the cud.
Omasum
Third compartment of stomach
- food swallowed again enters omasum
consists of many folds that squeeze the food to remove and reabsorb water.
Folds give omasum a large surface area
Abomasum
Final (4th) chamber
similar to mono gastric animals stomach
Known as the ‘true stomach’.
It produces gastric acids which contains hydrochloric acid (pH 2) which aid in chemical digestion
and enzymes that digest protein
Bloat
Occurs when gases get trapped in the rumen and build up.
It mainly occurs due to a large intake of clover.
-The left side of abdomen becomes distended
Treated by:
- Antacid
- Tube down to the stomach through the mouth
- Trocar and canula
Acidosis
Occurs when the pH of the rumen falls below 5.5.
Caused by diet too high in concentrates, rumen stops moving , appetite is lost.
Can result in shock and death of the animal.
Oesophageal groove
A channel, present in calves and lambs, that takes milk from the oesophagus into the abomasum and by passes the rumen, reticulum and omasum.
Small intestine
Duodenum, jejunum and ileum.
Absorbs the nutrients through the thin intestinal wall.
Bile
Made in the liver, stored in the gall bladder. Emulsify fats and lipids in the duodenum. Neutralise food that comes from the acidic stomach.
Large intestine
Contains the caecum and the colon. Absorbs water and pass the waste to the rectum for the egestion through the anus.
Cellulose
Cellulose is a polysaccharide Carbohydrate. Cellulose is composed of long chains of glucose molecules bonded together..
- Difficult to breakdown , used as fibre
Digestion in a young ruminant
When calf born, does not have a fully functioning ruminant digestive system.
- Instead have an oesophageal groove, which channels milk into the abomasum directly from the mouth.
- The opening of the oesophageal groove stimulated by calf suckling & eating roughage
- Allows culture of microorganism to develop in the rumen.
- AS animal grows , become less dependant on milk & transition to a diet of grass and concentrates
Pig Diet
Pigs require less fibre than cattle and more easily digestible nutrients such as protein.
Pigs are fed a concentrate ration, which must include high quality protein containing 10 of essential amino acids.
Liver
Food does not enter the liver
Produces bile (stored in gall bladder) to emulsify fats and lipids.
Pancreas
Food does not enter the pancreas
Secretes pancreatic juices
Compare calf diet with cow diet
CALF: Fed colostrum, then milk. High protein diet, fed minerals & vitamins, access to hay & concentrates to encourage scratch factor. Weaned at six weeks to grass & water.
COW: Has a low protein diet (unless pregnant or recovering from an illness
