Lec 13 - g System Pig Heterosis Sow Heterosis Rotational...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Breed - An identified group of animals with similar parentage and closed to outside animals. Purebred - An animal sired by a registered male and registered female of the same breed. Crossbred - Animal produced by mating two purebred parents of different breeds, a combination of a purebred and crossbred parent or crossbred parents. What is Heterosis? 1. Advantage in performance that crossbred animals express above the average of the purebreds. 2. Calculated as the percentage difference in breed composition of the parents. Two Types of Heterosis 1. Crossbred pig with purebred dam 2. Crossbred sow Heterosis The difference between the average performance of crossbred progeny and the average performance of their purebred ancestors Heterosis or hybrid vigor is caused by dominance or interaction effects of the genes. Two Types of Heterosis Individual Heterosis Caused by having a crossbred animal produced by purebred parents Maternal Heterosis Caused by having a crossbred dam HETEROSIS LEVELS Crossbreedin
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: g System Pig Heterosis Sow Heterosis Rotational Crossbreeding Systems 2 breed D,Y,D 67 67 3 breed D,Y,H,D 86 86 4 breed D,Y,H,C,D 92 92 2 breed Crossbred Boars YL, YL 50 50 Types of Gilts Type of Cross Example Heterosis F 1 Y*L or H*Y 100 F 2 (Y*L)*(Y*L) F 1 *F 1 50 3-breed cross L*(D-Y) or Y*(Y-L) 100 Backcross (YL)*(Y-L) 50 No name (YL)*(YD) 75 HETEROSIS EXAMPLES CROSS PIG HETEROSIS SOW HETEROSIS YORK X YORK LANDRACE X YORK 100 D X (YORK-LAND) 100 100 HD X (YORK-LAND) 100 100 DUROC X YORK-LAND 100 100 HAMP X (DUROC-YL) 100 100 YORK X (YORK-LAND) 50 100 DUROC X (YORK-YL) 100 50 Expected Crossbred Performance Weighed Mean of Purebreds [1 + (H M * % Mat. Het.) + (H I * % Ind. Het.)] Litter size H = 6.5 D = 8.0 L = 8.5 Y = 8.5 H M = 24% H I = 10% L, H, D Rotation = (6.5 + 8.0 + 8.5)/3 = 7.67 7.67 [(1 + (.86 * .24) + (.86 * .10)] = 9.91 HDx YL 8.5 * [1 + (H M * % Mat. Het.) + (H I * % Ind. Het.)] (1 + .24 + .10) * 8.5 = 1.34 * 8.5 = 11.39...
View Full Document

This note was uploaded on 03/01/2012 for the course ANSC 443 taught by Professor Staff during the Fall '08 term at Purdue.

Page1 / 3

Lec 13 - g System Pig Heterosis Sow Heterosis Rotational...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online