Estimating Rate of Inbreeding and Effective Population Size Using Genomic Data in Norwegian Red Cattle

Abstract Text: Traditionally, rates of inbreeding and effective population sizes have been estimated by the use of pedigree data. Here, inbreeding coefficients were estimated from runs of homozygosity in 322 Norwegian Red bulls born between 1982 and 2002. Further, inbreeding rates were estimated by regressing the natural logarithm of (1-F_ROH) on year of birth, resulting in an inbreeding rate per generation of 0.303 % and a corresponding effective population size of 165 individuals. This resembles the estimates made by the industry in 2011 based on pedigree information, giving an inbreeding rate of 0.26 % and an effective population size of 194. These results suggests that these two parameters can be estimated by the use of genomic data only, with possible application also to wild and/or endangered populations.

Keywords:

Effective population size (Ne)

Rate of inbreeding (ΔF)

Runs of Homozygosity (ROH)

Norwegian Red cattle