1 / 15

Animal Genetics

Animal Genetics. Introduction to Genetics. What is Genetics?. The science of heredity Genetics has also been described as the scientific study which deals with the differences and similarities among related individuals. Importance of Genetics.

darby
Download Presentation

Animal Genetics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Animal Genetics Introduction to Genetics

  2. What is Genetics? • The science of heredity • Genetics has also been described as the scientific study which deals with the differences and similarities among related individuals.

  3. Importance of Genetics • 1. Ability to develop animals with traits that are more desirable to the consumer. • 2. Develop animals that have increased productivity. • 3. Develop animals that have improved appearance and temperament.

  4. 4. A knowledge of genetics will help a producer in selection and breeding programs. • 5. To cut certain management costs (ex. Cost of dehorning).

  5. Basics of Modern Genetics • In each organism, there is a pair of genes, which control the appearance of a given characteristic. • The organism receives one gene from each of its parents. • Each of these genes is transmitted as a discrete, unchanging unit.

  6. When the reproductive cells (sperm and egg) are prepared, the genes separate and are distributed as units to each gamete. • If an organism has two unlike genes for a given trait, one may be expressed to the exclusion of the other.

  7. Units of Heredity • Genes determine the hereditary characteristics of animals and are transmitted to the offspring from the parents. • Genes are located on strands of DNA. • DNA is the backbone of the chromosome.

  8. Chromosomes • Microscopic rounded bodies in the nucleus of the cell. • Occur in pairs in body cells. • Number of chromosomes varies between species, but constant for each species.

  9. Number of ChromosomesPer Species • Cattle - 30 pair • Sheep - 27 pair • Goats - 30 pair • Swine - 19 pair • Chickens - 39 pair • Horse - 32 pair • Humans - 23 pair

  10. Dominance • Dominant gene - the gene in the pair that has the ability to cover up the presence of the other member of the combination. • P = polled, p = horned • Pp = polled because the dominant gene (P) masks the other (p).

  11. Recessiveness • Recessive gene - a gene in a combination that is masked by a dominant gene. • The recessive gene must be received by both parents in order to be expressed.

  12. Homozygous • Homozygosity in animals occurs when the individuals are pure for a certain characteristic. • PP = homozygous dominant • pp = homozygous recessive

  13. Heterozygous • When an animal has one dominant gene and one recessive gene. • Pp = heterozygous

  14. Genotype • Genotype is determined by its genes, it is the actual genetic make up of an animal. • Example: Homozygous PP for polled, Heterozygous Pp for polled.

  15. Phenotype • Phenotype is defined as the characteristics of an animal that can be seen and measured. • How the animal looks or a physical representation of traits. • Example: color patterns, presence of horns, length of body, etc...

More Related