TY - JOUR
T1 - Age-dependent genetic and environmental variance of semen quality in Nordic Holstein bulls
AU - Salimiyekta, Y.
AU - Jensen, J.
AU - Su, G.
AU - Gebreyesus, G.
PY - 2023/4
Y1 - 2023/4
N2 - The aim of this study was to estimate genetic and environmental parameters, across bull's age, for semen quality traits including pre- and postcryopreservation semen concentration, sperm motility, and sperm viability as well as ejaculate volume and number of doses per ejaculate. A data set on 96,595 ejaculates from 2,831 Nordic Holstein bulls collected between 2006 and 2019 was used. Genetic and environmental parameters were estimated using a random regression model and applying the average-information REML approach. Spline functions were chosen to fit the additive genetic and permanent environmental effects across bull's age, and the optimal number of knots was chosen using cross validation. Residual variance heterogeneity was assumed in different bull age classes. The estimated repeatabilities of semen quality traits ranged from 0.16 to 0.85 across different ages of bulls. The estimated heritabilities of semen quality traits ranged from 0.02 to 0.56 across different ages of bulls. The results indicate possibilities for genetic improvement of semen quality traits through selective breeding.
AB - The aim of this study was to estimate genetic and environmental parameters, across bull's age, for semen quality traits including pre- and postcryopreservation semen concentration, sperm motility, and sperm viability as well as ejaculate volume and number of doses per ejaculate. A data set on 96,595 ejaculates from 2,831 Nordic Holstein bulls collected between 2006 and 2019 was used. Genetic and environmental parameters were estimated using a random regression model and applying the average-information REML approach. Spline functions were chosen to fit the additive genetic and permanent environmental effects across bull's age, and the optimal number of knots was chosen using cross validation. Residual variance heterogeneity was assumed in different bull age classes. The estimated repeatabilities of semen quality traits ranged from 0.16 to 0.85 across different ages of bulls. The estimated heritabilities of semen quality traits ranged from 0.02 to 0.56 across different ages of bulls. The results indicate possibilities for genetic improvement of semen quality traits through selective breeding.
KW - AI performance
KW - heritability
KW - random regression model
KW - spline function
UR - http://www.scopus.com/inward/record.url?scp=85147561816&partnerID=8YFLogxK
U2 - 10.3168/jds.2022-22442
DO - 10.3168/jds.2022-22442
M3 - Journal article
C2 - 36759276
AN - SCOPUS:85147561816
SN - 0022-0302
VL - 106
SP - 2598
EP - 2612
JO - Journal of Dairy Science
JF - Journal of Dairy Science
IS - 4
ER -