Intro to Repro

Question 1

why do we study repro today

Answer 1

improvements in animal repro performance-> increased efficiency of food production->increased profit

Question 2

for dairy what is the measure of efficiency

Answer 2

days open

Question 3

for dairy what is the national average

Answer 3

150 days

Question 4

for dairy what is the realistic goal

Answer 4

110 days

Question 5

for beef what is the measure of efficiency

Answer 5

% calf crop

Question 6

for beef what is the national average

Answer 6

86%

Question 7

for beef what is the realistic goal

Answer 7

95%

Question 8

for sheep what is the measure of efficiency

Answer 8

% lamb crop

Question 9

for sheep what is the national average

Answer 9

108%

Question 10

for sheep what is the realistic goal

Answer 10

175%

Question 11

for swine what is the measure of efficiency

Answer 11

weaned pigs/ sow

Question 12

for swine what is the national average

Answer 12

15 pigs/sow

Question 13

for swine what is the realistic goal

Answer 13

20 pigs/sow

Question 14

for equine what is the measure of efficiency

Answer 14

% foal crop

Question 15

for equine what is the national average

Answer 15

60% of eligible mares foal

Question 16

what would happen if there was a 3% increase in repro rate

Answer 16

1 million more beef calves per year
3.2 million more pigs per year
3.7 million more gallons of milk per year

Question 17

what is asexual repro

Answer 17

reproduce by mitosis, characteristics of unicellular organisms

Question 18

what is advantage and disadvantage of asexual repro

Answer 18

advantage- simple and fast
disadvantage- no new genotypes formed, cant adapt to environmental change (except mutations)

Question 19

what is sexual repro

Answer 19

reproduce by meiosis, fusion of male and female gametes (higher forms), separate sexes

Question 20

what is advantage and disadvantage of sexual reproduction

Answer 20

advantage- new genotypes each generation
disadvantage- complex and length process

Question 21

what are oviparous

Answer 21

fish, amphibians, reptiles and birds

Question 22

explain oviparous

Answer 22

egg laying
embryonic development, and possibly fertilization occurs exterior to the bodyw

Question 23

what is ovoviviparous

Answer 23

certain reptiles and fishes

Question 24

explain ovoviviparous

Answer 24

fertilization and embryonic/ fetal development takes place in female repro as an egg
live young are born

Question 25

what are viviparous

Answer 25

almost all mammals

Question 26

explain viviparous

Answer 26

fertilization and all embryonic development occurs in female repro tract give birth to living young

Question 27

what is an exception of viviparous

Answer 27

monotremes who are mammals but they lay eggs