Transcript Comparative Nutrition

Population Genetics & Animal
Breeding
Lesson 1
Introduction to 311
Aims and objectives
This module aims to provide an understanding
of the principles and practices of animal
breeding and genetic improvement to enhance
animal productivity. It will give particular
emphasis on animal breeding in the Bhutanese
context.
Introduction to Population Genetics
Livestock plays a central role in the overall Bhutanese agriculture
production system. One of the main constraints to increasing
animal productivity in Bhutan is the breed with low genetic
potentials for high performance.
In view of this, one of the main interventions in the livestock sector
is to improve the breed through grading up of the native animal
with exotic high yielding breeds.
This module has 16 main topics which deals with the theory and
practice of animal breeding and breed improvement for increased
animal productivity.
Why is the module so important?
Understand the principles of population genetics
Understand how the Quantitative traits are inherited
Analyze the importance and causes of variation
Analyze the principles of regression and correlation between traits
Estimate heritability and repeatability of economic traits
Describe the traits of economic importance in livestock species
Describe the heritability and repeatability of various economic
traits and their correlation
Carry out the selection of animal for breeding based on different
selection methods and tools
Why is the subject so important?
State the importance of breeding in Animal Production
Explain inbreeding and its effects
Analyze the importance of crossbreeding and grading up
Describe the animal breed structure and various breeding
schemes
Evaluate the national livestock breeding policy
Analyze the constraints in animal breeding and production in the
country
Formulate breeding plans in different agro-ecological zones
Explain the importance of conservation of animal genetic
resources
Search, retrieve, evaluate and synthesize information related to
animal breeding
Module content
Unit 1. Quantitative genetics, Population genetics, Gene and gene frequency
Hardy-Weinberg Law, Factors affecting gene frequency and composition of
population
Unit 2. Quantitative traits and their inheritance
Unit 3. Variation, Nature and causes of variation in quantitative traits Measures of
central tendency and dispersion of quantitative traits Regression and
correlation
Unit 4. Regression and correlation between traits
Unit 5. Heritability and repeatability and methods for their estimation Traits of
economic importance in farm animals. Genetic correlation among economic
traits, their heritability and repeatability values
Module content
Unit 6. Origin and domestication of farm animals, consequences of domestication Breeds of
livestock and their development, Breeds of livestock and their development
Unit 7. Selection- Natural and artificial selection, Methods of selection- Tandem, independent
culling level and selection index Calculation of breeding values Selection tools-Mass
selection, Selection based on lifetime performance records, pedigree selection, progeny
testing, family selection
Unit 8. Genetic effects of selection, methods of estimating genetic gain Selection intensity,
Generation interval
Unit 9. Inbreeding, coefficient of relationship or inbreeding, inbreeding and its effect , Line
breeding and development of inbred lines
Unit 10. Outbreeding- outcrossing, crossbreeding, grading-up, heteriosis and complementarity
Module content
Unit 11. Animal Breeding structures and schemes- Closed nucleus
breeding, open nucleus breeding
Unit 12. Animal breeding systems in the country Opportunities for
breeding and improvement of farm animals in Bhutan National
Breeding Policy Constraints in breeding and improvement of livestock
productivity under various systems
Unit 13. Breeding plans for improvement of farm animals in different agroecological zones of Bhutan
Unit 14. Conservation of animal genetic resources
Unit 15. Seminar on different topics related to animal breeding
Teaching and Learning
The module involves:
43 hours of classroom lecture,
24 hours of practical,
24 hours assignment and
29 hours of self study
Assessment
Assessment
Continuous assessment
Written tests
Assignment
Practical Exam
Weighting
(60%)
30
20
10
Final assessment
Written Exam
Practical Exam
(40%)
30
10
References
Essential Reading:
Willis, M. B. 1991. Dalton’s Introduction to Practical
Animal Breeding. 3rd Edn. Blackwell Scientific
Publications, Oxford
Falconer, D.S. and Mackay, T.F.C. 1996. Introduction to
Quantitative Genetics. 4th edn. Longman, Harlow
Simm, G. 1998. Genetic Improvement of Cattle and
Sheep. Farming Press, Tonbridge
References
Additional Reading:
http://anthro.palomar.edu/mendel/mendel_1.htm
http://www.ndsu.edu/instruct/mcclean/plsc431/mendel/
mendel1.htm
http://www.netpets.com/dogs/reference/genetics/inbree
da.html
http://extension.missouri.edu/explore/agguides/ansci/g
02910.htm