swine selection

Question 1

what are the two components of swine performance?

Answer 1

1. genetic ability of the pig
2. environment (nutrition, health, facilities, management practices, etc.)

Question 2

what is the hampshire breed good for? what are they not strong in? sire or dam?

Answer 2

good for muscling, not strong for littersize and mat., great for sire side

Question 3

what is the duroc breed good for? sire or dam used in crosses? what are they not strong in?

Answer 3

rugged, meaty, fast growing, good mothers; sire; problems with fatness

Question 4

what is the yorkshire breed good for? sire or dam? what are they not strong in?

Answer 4

large litters and good mothers; dam; not best for muscling

Question 5

what breed is the large white similar too? why are they no longer considered the same breed?

Answer 5

yorkshire; similar characteristics, different genetic base

Question 6

what breed does the chester white have similar genetics to? how are they different? what are characteristics of the chester white?

Answer 6

duroc; slower growth and more fat; durable breed and have a preferred coat color

Question 7

what is the landrace breed good for? sire or dam used in crosses? what is this breed usually identified by?

Answer 7

long bodied and prolific; dam; its large floppy ears

Question 8

what breed is the poland china similar to in body conformation? what is their coloration?

Answer 8

chester white; black with white points

Question 9

what is the history of the spot breed in swine?

Answer 9

they were originally derived from polands that failed to adhere to color rules and the spots were able to make more progress in improvements

Question 10

what characteristic are Berkshire pigs distinguished by? what breed are they similar to? what are their strengths?

Answer 10

snub, turned up nose and black and white spots color pattern; durocs; produce fine grain of meat and fatness and is highly desired in the japanese pork trade

Question 11

what is the pietrain breed strong in? what stress gene do they carry? where did they originate?

Answer 11

heavy muscling; stress gene associated with high muscling but susceptible to PSE problems and stress; europe

Question 12

where did the large black originate? what breed are they analogous to?

Answer 12

britain; large white

Question 13

where is the hereford swine breed unique to? where were they developed?

Answer 13

USA; iowa and nebraska

Question 14

where did the meishan breed originate? what are they noted for?

Answer 14

china; they reach puberty at 3 months and have larger litters

Question 15

what is the goal of the swine genetics program?

Answer 15

• to not allow inferior genetics or the mating system to limit production performance
• to identify a better source of if genetics is the limited factor in obtaining maximum performance
• to make sure you are using the correct mating system that maximizes performance
• to be sure that herd health is not limiting performance

Question 16

what happens if herd health is found to be limiting performance?

Answer 16

• it may require herd depopulation and repopulation with healthy superior genetics
• may be costly
• if relocating operations, this may be a good time to update genetics and improve health

Question 17

what are the genetic resources available for swine selection?

Answer 17

• genetic supplier
• breeds or lines
• choice of individual animals within the population of choice
• mating systems
• selection at the nucleus, multiplier, and commercial levels

Question 18

what is selection differential? what does it impact?

Answer 18

the average(GV) of the animals you select to the entire group of potential select animals; the rate of genetic process

Question 19

how should you chose a swine mating system?

Answer 19

chose one that matches your management preference, maximizes heterosis, and makes use of breed complementarity