Exam 2 - Animal Science 501

Stomach of a Ruminant

• Large fermentation vat

• Microorganisms break down cellulose

• Creates lots of gas (methane)

• Some nutrients absorbed

• Roughages are reduced in size

What is rumination?

• Eating rapidly, regurgitating and masticating their feed. (Chewing their cud)

Rumen

• 40 gallons in cow

• large fermentation vat

• microorganisms digest cellulose

• covered with papillae to increase surface area

• microorganisms synthesize amino acids from nonprotein nitrogen & synthesize B-complex vitamins

Reticulum

• Magnets are placed here to prevent metal from puncturing

Omasum

• Manypiles

• Bible stomach

• Water and particle size

Abomasum

• True stomach

• Glandular stomach (HCl, pepsin, rennin)

• In calf= 80% of stomach

• In adult cow= 10% of stomach

Order that food travels in ruminants

1) Rumen

2) Reticulum

3) Omasum

4) Abomasum

Small Intestine Function

• Long, coiled tube connecting the stomach with the large intestine

• Final breakdown and absorption of nutrients occurs here

• covered by villi which increases surface area to increase absorption

• Food moves through by muscle contractions called peristaltic movement

Large intestine function

• Absorbs water

• Very little nutrient absorption takes place here

What are the accessory organs ?

• Pancreas

• Liver

Pancreas function

• secretes enzymes which breaks down fat and starches

Liver function

• secretes bile which emulsifies fats

What are the 6 essential nutrients ?

1) water

2) protein

3) carbohydrates

4) fats

5) minerals

6) vitamins

Protein

• amino acids

• carbon, hydrogen, oxygen, nitrogen

Common nutritional disorders

• hardware disease

• acidosis

• goiter

• colic

• milk fever

• ketosis

• anemia

• bloat

Causes of hardware disease

• wires, nails, etc lodged in reticulum from accidentally eating

Causes of Acidosis

• Excess grain consumption in ruminants

Causes of Goiter

• Iodine deficiency

Colic

• Most common nutritional disorder in horses

Milk fever

• Calcium gluconate used to treat

• sudden drop in blood calcium levels

Ketosis

• Challenge feeding

• DCAD

Anemia

• Low iron levels

• Fe-dextran injection used to treat

Bloat

• Trocar (hollow needle) used to release gas

Examples of crude protein

• Soybean meal

• Cottonseed meal

• Linseed meal

• Peanut meal

• Alfalfa hay

How much crude protein does SBM (soybean meal) have ?

• 200 lbs of SBM has 7.3% N

Carbs/Sugars

• Carbon, Hydrogen, Oxygen

• Monosaccharides (glucose, fructose,
  galactose)

• Disaccharides (lactose, sucrose, maltose)

• Polysaccharides (starch, cellulose, gums)

DM

Dry Matter

• what remains when water is removed from a feed

Gross Energy

The total amount of energy in a feed

DE

Digestible Energy

• The amount of energy in a feed digested by the animal, expressed in Mcal or Kcal

DE = GE

• energy found in the feces

NE

Net Energy

• The amount of energy in a feed used for specific body functions

NE = GE

• fecal energy + gaseous & urinary energy + heat increment

ADF

Acid Detergent Fiber

• Increases with plant maturity

Fats

• Fatty acids + Glycerol

• Carbon, Hydrogen, Oxygen

Unsaturated fats are prone to ?

Rancidity

Hydrogenation Process

• prevents rancidity

• adds hydrogen to become Trans-fat, unhealthy for humans

Where is fat stored in the animal body?

• Subcutaneous

• Surrounding internal organs

• Marbling and milk

Macro Minerals

Required in larger amounts

• Calcium

• Phosphorus

• Sodium

• Chlorine

• Sulfur

• Potassium

• Magnesium

What function does this mineral provide ?

Calcium

• Skeletal formation and maintenance

• Mineral/vitamin relationship

What function does this mineral provide ?

Phosphorus

• Skeletal formation and maintenance

• Protein synthesis

What function does this mineral provide ?

Iron

Oxygen transport

What function does this mineral provide ?

Sodium

• Fluid balance

• Acid-base balance

What function does this mineral provide ?

Chlorine

• Fluid balance

• Acid-base balance

What function does this mineral provide ?

Potassium

• Fluid balance

• Acid-base balance

What function does this mineral provide ?

Selenium

Micro mineral (little required)

• Mineral/vitamin relationship

Vitamins are essential for…. ?

• Health

• Reproduction

• Lactation

• Growth

• General maintenance

Avian Digestive System: Function of

Mouth/Beak

• To gather and break down feed

Avian Digestive System: Function of

Esophagus

• Tube from mouth to stomach that is open at the mouth end

Avian Digestive System: Function of

Crop

• Feed storage and moistening

Avian Digestive System: Function of

Proventriculus

• Glandular stomach (HCl, and gastric juices)

• Enzymatic

Avian Digestive System: Function of

Gizzard

• Muscular stomach

• Mechanical breakdown

Purpose of dairy industry

• Production of milk for human consumption

• Protein & Calcium

1862 - Land Grant Act

• College of Agriculture in every state

1887 - Hatch Act

• Experimental Stations

• Research on dairy cattle and processing

1890 - Babcock Test

• Tuberculosis (TB) testing in fat

Louis Pasteur

• Created pasteurization, where heat is used to destroy harmful microorganisms

Homogenization (1919)

• Breaks up fats in milk so that there’s no separation

What are the top states in cow numbers ?

In order:

• California

• Wisconsin

• Idaho

• Texas

• New York

Examples of Ruminant Animals

• Cow

• Sheep

• Goat

• Giraffe

• Deer

Where does a dairy farms income come from ?

• Milk

• Calves

• Cull cows

Dairy farm expenses

• Feed

• Herd replacement

• Labor

• Utilities

• Chemicals

• Taxes

• Vet care

Breeds of Dairy Cattle: Holstein

• Largest of dairy breeds

• Most common (90-95% of all dairy cattle in U.S.)

• Produces the most milk

• Cows docile, Bulls aggressive

• From Holland & Northern Germany

Breeds of Dairy Cattle: Guernsey

• Produce golden yellow milk (High carotene)

• High milk fat (4.55%) and protein (3.57%)

• Poor beef due to small size

Breeds of Dairy Cattle: Jersey

• High milk fat 4.75% (top in dairy breeds)

• High protein 3.79%

• Smallest breed

• Nervous cows & Mean bulls

Breeds of Dairy Cattle: Brown Swiss

• Oldest breed

• Strong feet and legs

• 2nd in milk production

• MF: 4.0%

• Good for beef, large frame

Breeds of Dairy Cattle: Ayrshire

• Known for conformation; straight lines and well balanced udders

Holstein breeding weight ?

750lbs

Brown Swiss breeding weight ?

750lbs

Ayrshire breeding weight?

600lbs

Guernsey breeding weight?

550lbs

Jersey breeding weight ?

500lbs

Best age for breeding cattle?

• 13-15 months

What is a Springer ?

• a Heifer (young cow) due to calve in 2 months or less

What is a Dry Cow ?

• A dairy cow that is in a resting period before giving birth

• No longer being milked

Challenge Feeding

• 2-3 weeks before calving

• Gradually increasing grain concentrates