Lamb wool shedding is a good predictor of ewe wool shedding

Authors

Napoleón Vargas Jurado, University of Nebraska - Lincoln
Larry Kuehn, USMARCFollow
Ronald M. Lewis, University of Nebraska - LincolnFollow

ORCID IDs

Ronald M. Lewis https://orcid.org/0000-0002-1658-443X

Document Type

Article

Date of this Version

2020

Citation

J Anim Breed Genet. 2020;137:365–373.

DOI: 10.1111/jbg.12449

Comments

U.S. govt work

Abstract

Interest in reducing labour costs due to shearing has led to development of breed types that shed their wool naturally. Selection at young ages can facilitate response. Reliability of predictions of adult from lamb wool shedding (WS) is thus key in the design of breeding programmes to increase shedding. Our objectives were to estimate heritabilities and genetic relationships between WS measured once in lambs and repeatedly in ewes and to assess the accuracy of lamb WS EBV to predict ewe WS EBV based on a multi‐trait threshold or a repeatability model. Data were 4,971 lamb and 3,335 ewe WS records on a Romanov, White Dorper and Katahdin composite flock. For the multivariate model, WS heritability ranged from 0.47 ± 0.03 in lambs to 0.59 ± 0.04 at 1 year of age. For the repeatability model, WS in adult ewes was moderately heritable (0.50 ± 0.03) and repeatable (0.60 ± 0.02). Genetic correlations were 0.72 ± 0.04, 0.65 ± 0.05, 0.50 ± 0.09 and 0.51 ± 0.09 between lamb WS and 1st through 4th record, respectively. Given the moderately high heritability and high correlations between WS performance in lambs and ewes, selecting animals early in life would effectively increase WS in crossbred flocks.