Principles of Selection and Reproductive Tech
32 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What traits are more likely to survive and reproduce?

Traits that are more likely to survive and reproduce are those that are advantageous to the organism's survival and ability to pass on its genes.

What is natural selection?

Natural selection is the process by which organisms better adapted to their environment tend to survive and reproduce more successfully than those less adapted, leading to the evolution of new species.

What are the ______ patterns of selection?

four

The ______ of the animal's breeding value is estimated in genotypic selection.

<p>breeding value</p> Signup and view all the answers

The primary goal of artificial selection is to preserve the natural diversity of a species.

<p>False</p> Signup and view all the answers

In artificial selection, the goal is to ______ desired traits in a population of organisms.

<p>enhance</p> Signup and view all the answers

Sexual selection only involves female choice of mates.

<p>False</p> Signup and view all the answers

What is the difference between intersexual and intrasexual selection?

<p>Intersexual selection involves one sex choosing a mate based on certain traits, while intrasexual selection involves competition between members of the same sex for access to mates.</p> Signup and view all the answers

In what way are the tails of peacocks an example of sexual selection?

<p>Peacocks have extravagant tails that they use to attract peahens. Females are attracted to males with larger, more elaborate tails. Therefore, males with larger tails are more likely to mate and pass on their genes, leading to the evolution of this exaggerated trait.</p> Signup and view all the answers

What is the ______ in selection of animals?

<p>process</p> Signup and view all the answers

What are the two stages of selection in livestock breeding?

<p>Phenotypic and genotypic</p> Signup and view all the answers

Select the correct statement about phenotypic selection.

<p>It is often the first step in selection and involves assessing an animal's traits directly.</p> Signup and view all the answers

Genotypic selection relies solely on the observed performance of an animal.

<p>False</p> Signup and view all the answers

Which of the following is NOT a factor considered in genotypic selection?

<p>Individual animal's direct performance</p> Signup and view all the answers

In which of these situations would selection from relatives' performance be most useful?

<p>When evaluating traits that are influenced by environmental factors and measured late in life.</p> Signup and view all the answers

What are the three methods of multiple trait selection?

<p>The three methods of multiple trait selection are the tandem method, independent culling levels (ICL), and total score or selection index.</p> Signup and view all the answers

Which multiple trait selection method is known for being time-consuming due to its sequential approach to improving traits?

<p>Tandem method</p> Signup and view all the answers

What is the core principle of the independent culling levels (ICL) approach?

<p>In ICL, a minimum standard for each trait is set, and animals that fall below those standards are culled, regardless of their performance in other traits.</p> Signup and view all the answers

ICL is advantageous because it eliminates animals based on their performance across all desired traits.

<p>False</p> Signup and view all the answers

A disadvantage of ICL is the potential to cull valuable animals that fail to meet the minimum standard for only one trait.

<p>True</p> Signup and view all the answers

How does the total score or selection index differ from independent culling levels?

<p>The total score or selection index method assigns a weighted score to each trait, and the total score for an animal serves as the selection criterion. In contrast, ICL utilizes predetermined culling levels for each individual trait.</p> Signup and view all the answers

In the total score or selection index approach, animals are chosen for breeding based on a weighted sum of their scores for each trait.

<p>True</p> Signup and view all the answers

In the sample problem, the swine breeder is selecting for what two traits?

<p>The swine breeder is selecting for increased number of pigs weaned (NW) and reduced backfat (BF).</p> Signup and view all the answers

Which of the following is a benefit of using artificial insemination for livestock breeding?

<p>All of the above</p> Signup and view all the answers

Cryopreservation involves freezing semen or embryos at extremely low temperatures.

<p>True</p> Signup and view all the answers

What is the primary goal of multiple ovulation and embryo transfer (MOET)?

<p>MOET aims to increase the number of offspring from elite animals, by inducing multiple ovulations in selected females and transferring those embryos to recipient animals, thus maximizing the genetic potential of valuable individuals.</p> Signup and view all the answers

Which of the following is NOT a step typically involved in MOET?

<p>Cloned embryos are created to increase the number of offspring</p> Signup and view all the answers

In Vitro Fertilization (IVF) occurs outside the living organism.

<p>True</p> Signup and view all the answers

What is the purpose of sorting sperm in IVF?

<p>Sperm can be sorted based on their sex chromosomes (X or Y), allowing for the selection of embryos carrying the desired sex. This can be particularly useful in livestock breeding for specific applications.</p> Signup and view all the answers

Nuclear transfer or cloning primarily involves the transfer of nuclear material from one cell to another.

<p>True</p> Signup and view all the answers

Cloning, as a breeding technique, is not used in agricultural settings.

<p>False</p> Signup and view all the answers

What is the main advantage of using cloning for livestock breeding?

<p>Cloning allows farmers to create exact genetic copies of exceptional livestock, preserving desirable traits and ensuring the continuation of those qualities in future generations.</p> Signup and view all the answers

Study Notes

Unit X: Principles of Selection and Assisted Reproductive Technologies

  • Course is titled Principles of Selection and Assisted Reproductive Technologies.
  • Instructor is Clarissa Therese M. Mordeno, DVM.

Objectives

  • Evaluate selection concepts within herd environments.
  • Discuss advantages and limitations of selection methods for various traits.
  • Detail common applications of assisted reproductive technologies in animal production.

Outline

  • Recall patterns of selection
  • Sexual Selection
  • Artificial Selection
  • Multiple Trait Selection
  • Assisted Reproductive Technologies in Animals

Recall: Natural and Sexual Selection

  • Natural selection: traits more likely to survive and reproduce.
  • Sexual Selection: involves traits that are attractive to the opposite sex and encourage survival. Examples such as peacocks with extravagant tails.

Mechanisms of Sexual Selection

  • Inter-sexual selection (mate choice): involves individuals based on traits. Examples are male dancing courtship and females choosing.
  • Intra-sexual selection (mate competition): involves one sex competing for another. Examples include male deer battling with antlers and male elephant seals.

Artificial Selection

  • Artificial selection: purposefully selecting desirable traits in animals. Example is selectively breeding cattle for meat or milk.
  • Example: Pugs displaying traits of smaller eyes, longer nose, a curly tail, and a flat nose.

What is the Process in Selection of Animals?

  • Selection is evaluated in multiple stages.
  • Phenotypic (Initial) Selection focuses on initial traits for breeding based on performance. (e.g. reproductive system)
  • Genotypic (Final) Selection estimates the breeding value of the animal. (e.g. parental, collateral relatives, progeny traits).

Basis and Importance of Selection from Relative’s Performance

  • When evaluating individual selection
  • When selection needs to occur in earlier generations
  • Examples of these traits in animals include milk production, egg production, and mature weight.
  • Selection is also important when the heritability (h²) of the trait under selection is low.

Multiple Trait Selection

  • Selection of multiple traits, which are commonly of economic importance.
  • Three methods: Tandem Method, Independent Culling Levels (ICL), and Total Score or Selection Index.

Tandem Method

  • Selecting traits in succession.
  • First improve Trait A, then Trait B, and so on.
  • Takes more time for improvement overall
  • The efficiency of the method is impacted by possible correlations among traits.

Independent Culling Levels (ICL)

  • Independent selection for each trait.
  • An animal is culled if it does not meet the required level on any one trait.
  • Advantages: selection for multiple traits.
  • Disadvantages: more emphasis, and effectiveness depends on levels kept for each trait.

Total Score or Selection Index

  • Selects for numerous traits simultaneously.
  • Differs from ICL by assigning specific scores (index values) to each trait based on importance.

Assisted Reproductive Technologies in Animals

  • Artificial Insemination (AI): introducing semen into the female reproductive tract
  • Cryopreservation: freezing semen or embryos for storage.
  • Multiple Ovulation and Embryo Transfer (MOET): inducing ovulation, collecting embryos, and transferring to foster mothers.
  • In Vitro Fertilization (IVF): fertilizing eggs outside the animal's body, then implanting embryos.
  • Sex Determination of Sperm: separating X-bearing and Y-bearing sperm for specific sex selection.
  • Nuclear Transfer or Cloning: introducing nucleus of a somatic cell into an oocyte to create an embryo for a clone.

Sample Problems

  • Demonstrating calculation of boars ranking with different traits.
  • Determining how different selection techniques would affect boar selections.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Unit X: Principles of Selection and Assisted Reproductive Technologies PDF

Description

This quiz covers key concepts in animal selection and reproductive technologies. It evaluates selection methods, including natural and sexual selection, as well as artificial selection and their applications in animal production. Test your knowledge on these important principles.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser