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Dairy Cattle Selection
Dairy Cattle SelectionOverview
• Dairy Terms and Definitions• Parts of a Dairy Cow• Dairy Traits and Selection
Dairy Cattle Selection
1. What is a bull? Mature male dairy animal2. What is a heifer?Female dairy animal that has not borne an offspring3. The percent of fat in the milk is called what?Butterfat4. A cow showing signs of pregnancy is considered what? Springer5. What is a cow? Mature female dairy animal; shows evidence of having produced one
or more calves6. What is the term for the span of time that a cow is giving milk? Lactation period7. What is the term for the amount in pounds of milk that a cow
produces during a lactation period?Milk production
Dairy Cattle Selection
8. What is the term for the manner in which an animal acts? docile9. DHI is an acronym for what?Dairy Herd Improvement 10. The parts of the cow directly responsible for producing and storing
milk is called what?mammary system11. An undesirable defect is called a what?discrimination12. What is the term used for register of lines of ancestry?pedigree
Dairy Cattle SelectionParts of a Dairy Cow
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
1. Stature (measured at withers) Extremely Tall
2. Chest and body (considering age and stage of lactation) Extremely Deep Body
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
3. Dairy character (independent of performance)
4. Foot and shape (angle)
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
5. Rear legs (side view)
6. Pelvic angle
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
7. Rump width
8. Fore udder attachment
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
9. Rear udder width (at attachment)
10. Rear udder height (at attachment)
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
11. Teat placement (rear view)
12. Suspensory ligament (cleft)
Dairy Cattle SelectionTraits and Selection (Dairy Evaluation System)
13. Udder depth
Dairy Cattle SelectionTraits and Selection
Milk Production FactsBreed Percent Butterfat Pounds Butterfat Pounds Milk
Prod Holstein 3.66 703 19,185Ayrshire 3.95 569 14,398Jersey 4.75 618 13,020Brown Swiss 4.03 606 15,062Guernsey 4.57 611 13,363
Think about this?1. Which breed produced the most total pounds of milk? Why do think this is so?2. Why would butterfat be important to milk?3. What breed produced the lowest total pounds of butterfat?4. What would you think the most popular breed of Dairy cattle would be judging from
this data? Why?
Dairy Cattle SelectionTraits and Selection Terms
• balance of symmetry - proper proportions and blending of parts.• clean - free from fat• cow-hocked - rear legs turned so that the hocks are close together
and feet point out when viewed from the rear.• body capacity - total amount of volume exhibited by a cow and
indicated by a combination of depth of fore and rear rib, length of barrel, spring of rib and depth of flank.
• quality - overall smoothness, blending of shoulders, and refinement of head and bone.
• spring of rib - amount ribs arch out from the backbone.• type - combination of characteristics that make an animal most
useful for a specific purpose.• sickle-hocked - rear legs too curved when viewed from the side.
What other terms might you use?
Dairy Cattle SelectionTraits and Selection Factors to Consider
• General appearance - Cows with good general appearance are attractive, have femininity, vigor, stretch, scale and a harmonious blend of all parts.
• Evaluate all parts of the cow when considering general appearance.• Dairy character - Dairy character refers to a combination of
characteristics that indicate a cow’s ability to convert feed into milk. Characteristics include angularity, freedom from coarseness, and evidence of milking ability with udder quality.
• Udder - The udder should be large enough to produce and store milk. – The length, width, and depth of the udder determines its capacity. – The udder should be attached high and wide behind and carry well forward in
front. Other factors considered would be teat placement, size and prominence of the mammary veins, and number and size of milk wells.