Answered

Get the answers you need at Westonci.ca, where our expert community is always ready to help with accurate information. Discover detailed solutions to your questions from a wide network of experts on our comprehensive Q&A platform. Our platform provides a seamless experience for finding reliable answers from a network of experienced professionals.

You are hired by Murphey Farms to decrease the backfat in their hogs. The current hog population has a mean backfat content of 20.2mm. You selected the hogs with the smallest amount of backfat, mated them and obtained the progeny generation. The selected hogs had a mean backfat content of 9.5mm. You know that the heritability for percent backfat in hogs is 0.47.
1. What is the selection differential? Round your values properly to 2 decimal digits.
2. What is the expected response to selection? Round your values properly to 2 decimal digits.
3. What is the expected mean of the progeny generation? Round your values properly to 2 decimal digits.

Sagot :

marianaegarciaperedo

Answer:

  1. SD = -10.7
  2. R = -5.3
  3. X₁ = 14.9 ≅ 15mm

Explanation:

Before answering the question, we need to know a few concepts.

Artificial selection is the selecting practice of a specific group of organisms in a population -that carry the traits of interest- to be the parents of the following generations.  

Parental individuals carrying phenotypic values of interest are selected from the whole population. These parents interbreed, and a new generation is produced.  

The selection differential, SD, is the difference between the mean value of the trait in the population (X₀) and the mean value of the parents, (Xs). So,  

SD = Xs - X₀    

Heritability in the strict sense, h², is the genetic component measure to which additive genetic variance contributes. The heritability might be used to determine how the population will respond to the selection done, R.  

h² = R/SD

The response to selection (R) refers to the metric value gained from the cross between the selected parents. R can be calculated by multiplying the heritability h², with the selection differential, SD.  

R = h²SD  

R also equals the difference between the new generation phenotypic value (X₁) and the original population phenotypic value (X₀),  

R = X₁ - X₀  

-------------------------------------------------------------------------------------------------------------

Now that we know these concepts and how to calculate them, we can solve the proposed problem.

Available data:  

• You are decreasing the backfat in the hogs.

• The hog population mean backfat content = 20.2mm → X₀

• The selected hogs had a mean backfat content of 9.5mm → Xs  

• Heritability is 0.47 → h²

According to what we sow previously, we need to find out the value of X₁, which reflects how tall the new generation of corn will grow.  

• We know that R = X₁ - X₀, so we need to clear this formula to calculate X₁

X₁ = R + X₀  

We already know that X₀ = 20.2mm  

Now we need to calculate R.  

• R = h²SD  

We know that h² = 0.47,  

Now we need to calculate SD

• SD =  Xs - X₀  

Xs = 9.5mm → Parentals media height

X₀ = 20.2mm → Population media Height

SD = Xs - X₀  

SD = 9.5 - 20.2

SD = -10.7  

Knowing this, we can calculate R

R = h²SD

  • h² = 0.47  
  • SD = -10.7

R = 0.47 x -10.72

R = -5.3

Finally, once we know the R-value we can calculate the X₁ value

X₁ = R + X₀

X₁ = -5.3 + 20.2

X₁ = 14.9 ≅ 15mm

Thank you for your visit. We're dedicated to helping you find the information you need, whenever you need it. We appreciate your time. Please come back anytime for the latest information and answers to your questions. We're dedicated to helping you find the answers you need at Westonci.ca. Don't hesitate to return for more.