New Zealand lamb breeders measure the following variance values for their herd.

ID: 43528 • Letter: N

Question

Part A

Calculate the broad sense heritability (H2) for body mass trait in this lamb herd.

Part B

Calculate the narrow sense heritability (h2) for body mass trait in this lamb herd.

Part C

Calculate the broad sense heritability (H2) body fat trait in this lamb herd.

Part D

Calculate the narrow sense heritability (h2) for body fat trait in this lamb herd.

Part E

Calculate the broad sense heritability (H2) for length trait in this lamb herd.

Part F

Calculate the narrow sense heritability (h2) for length trait in this lamb herd.

Trait VP VG VA Body mass (kg) 39.8 18.5 6.4 Body fat (%) 41.3 17.7 6.7 Body length (cm) 46.3 22.4 6.9

Part A:

Broad sense heritability measures the ratio of total genetic variance/ total phenotypic variance

H2= Var(G)/Var(P)

H2 (body mass) = 18.5/39.8

= 0.4648

Part B:

narrow sense heritability is the ratio of total additive variance to total phenotypic variance

h2= Var A/Var P

h2(body mass)= 6.4/ 39.8

=0.1608

Part C:

H2 for body fat trait= 17.7/41.3

= 0.4285

Part D:

h2 for body fat trait= 6.7/41.3

0.1622

Part E:

H2 (body length)= 22.4/46.3

= 0.4838

Part F:

h2(body length) = 6.9/43.3

= 0.1490