- -  AGRICULTURE CORE CURRICULUM  - -

(CLF3000)  Advanced Core Cluster:  ANIMAL SCIENCE

  (CLF3250)  Unit Title:  LIVESTOCK BREEDING AND GENETICS

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  (CLF3299)  Topic:  UNIT EXAM               Time       Year(s) 
                                            1 hour       3 / 4        
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TOPIC PRESENTATION:  UNIT EXAM


UNIT EXAM:  LIVESTOCK BREEDING AND GENETICS

NAME_______________________________________________

DATE_______________________________________________

PER._______________________________________________


1.  What is a chromosome?



2.  Briefly describe the Chromosome Theory of Inheritance:




3.  Answer TRUE or FALSE to the following questions:

__________   Phenotype refers to the genetic make-up of the animal.

__________   An allele is a single chromosome in a chromosome pair.

__________   Genotype refers to the physical appearance or production 
             of the animal.

__________   A homozygous gene pair occurs when both genes code for 
             the same variation of some trait, ("bb" codes for red 
             coat color in cattle).

__________   Mutation occurs when the molecular structure of genes or
             chromosomes is changed.

__________   Variation refers to genetic differences between 
             individuals.



4.  What is the difference between oogenesis and spermatogenesis?





5.  Given the trait of color in swine, "W" = white and "w" = other 
    color, what would be the percent of white piglets if we make the
    following cross?  Show your work!

                         Ww x Ww
                                             Answer___________

6.  If we cross white faced, horned cows with the genotype "Wwpp", to
    pure black, polled bulls with the genotype "wwPP", what percent 
    of each variation will we get?  Show your work:




                                             Answer___________

7.  Give an advantage and disadvantage of the following breeding
    systems:

                           ADVANTAGE             DISADVANTAGE
                     ____________________   _________________________

Inbreeding


Line breeding


Out crossing


Cross breeding



8.  What does hybrid mean?




9.  Why does the cross between a mare and a donkey produce sterile 
    offspring?





9.  Define prepotency?



10. Explain briefly the process of 2 methods of embryo transfer.  



11. Embryo transfer is most commonly used on which livestock?





12. Describe the impact that embryo transfer could have on the 
    improvement of the gene pool in an animal breed.







13. List 4 factors to consider in a bull fertility test:

    a.


    b.


    c.


    d.



14. Briefly explain the process of artificial insemination:






15.  how has artificial insemination affected (genetically) the dairy 
     industry?




16. What are three visible and/or behavioral signs of estrus?  List the 
    sign and the species of animal it is observed in:

       ANIMAL           SIGN
    ______________|__________________________________________________
a.                |
                  |
b.                |
                  |
c.                |
                  |

17. How do the following heat detecting devices function?

    Chin-ball marker:



    Pressure sensitive patch (Heat-mount detector):



    Marking harness:



18. Describe the 3 stages of parturition, and explain each stage:

    Stage 1 - 




    Stage 2 - 




    Stage 3 - 

19. Describe the proper fetal presentation, (draw a picture):





20. What is uterine dystocia?  



21. List 2 causes of dystocia?




22. What is a freemartin?   





23. What should be done with a freemartin?





24. Answer TRUE or FALSE to the following questions:

__________   The pregnant female should not be allowed to exercise,
             since this causes the fetus to grow too large.

__________   Pregnant females may need extra feed during the last 
             trimester, since this is when most fetal growth occurs.

__________   Male breeding stock should be allowed plenty of exercise 
             and not allowed to become too fat.

__________   Tincture of iodine may be applied to the umbilical cord 
             of a newborn in order to sterilize it.

__________   Damp, drafty barns are okay for young lambs, but not for 
             young pigs.

__________   Beef, sheep, and swine can all be kept together during 
             gestation.


25. Describe proper feeding for a sow during gestation, lactation,
    and parturition.  Include information on protein level at each 
    stage.









26. What is heterosis?





27. What is complementarity?






28. Identify a common cross for the following species:

    Beef cattle:


    Sheep:


    Swine:

4/16/90 bkm/sg/gv


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