Genetic Relationship of Productive Life, Production and Type Traits of Korean Holsteins at Early Lactations

Abstract

The present study was performed to study the genetic relationship of productive life with production and type traits of Korean Holsteins at first three lactations. The data for the analysis from 56,054, 28,997, and 11,816 animals of first, second and third parity cows which were born from 2006 to 2011 were collected by Dairy Cattle Improvement Center, National Agricultural Co-operative Federation. Milk, protein and fat yields adjusted for 305 days and average somatic cell score considered as production traits and analyzed type traits were stature, strength, body depth, dairy form, rump angle, rump width, rear leg side view, foot angle, front attachment placement, rear attachment height, rear attachment width, udder cleft, udder depth, front teat placement and front teat length. A multi trait genetic analysis was performed using Wombat program with restricted maximum likelihood animal model composed of fixed effect of birth year, farm and the random effect of animal and random residual effect according to the traits. Heritability estimates of productive life were between 0.06 and 0.13. Genetic and phenotypic correlations between production and productive life traits ranged from 0.35 to 0.04 for milk, 0.16 to 0.05 for protein and 0.18 to 0.02 f 15-0034 (2nd) 150520 or fat. Somatic cells score showed a negative genetic and phenotypic correlation with productive life and also udder type traits, indicating that the selection for higher udder traits will likely to improve resistance to mastitis and persistence in the herd. Among all dairy form type traits, udder characters such as udder cleft showed a significant relationship with productive life. However, a specific change of heritabilities or correlations were not observed with the change of parity. Moreover, further studies are needed to further confirm the significance of the above traits and the effect of parity on above relationships in order to minimize both voluntary and involuntary culling rates while improving herd health and maintaining high yielding dairy cows.

Analysis of culling records and estimation of genetic parameters for longevity and some production traits in Holstein dairy cattle

“…Similar results can be seen in Harris et al (1992) and Vukašinović et al (1995). However, Wasana et al (2015) reported lower estimates of genetic correlation of productive life and production traits in three parities for Korean Holstein. Their estimates were in the range of 0.04-0.35 for milk yield and 0.02-0.18 for fat yield.…”

Genetic correlation and genome-wide association study (GWAS) of the length of productive life, days open, and 305-days milk yield in crossbred Holstein dairy cattle

“…A favorable positive correlation was observed between the production trait FM305 and functional trait LPL ( r , LPL, FM305 g = 0.43) mainly because the dairy cattle producers prefer to keep high-milk-yielding cattle in the herd. The positive genetic correlation between FM305 and LPL was also reported by Irano et al (2014) and Wasana et al (2015). Our results also demonstrate an unfavorable positive correlation between FM305 and DO ( r , DO, FM305 g = 0.14), indicating that the genetic selection for high milk yield could reduce the fertility of dairy cattle as previously pointed out by Van Raden et al (2004).…”

“…However, the milk heritability was slightly lower than the values reported by Irano et al (2014), Tsuruta et al (2005), Pritchard et al (2013), which were 0.28, 0.4, and 0.3, respectively. The heritability of LPL was also slightly lower than the value (0.13) reported by Wasana et al (2015).…”

Genetic parameters for milk traits, somatic cell, and total bacteria count scores in Brazilian Jersey herds

“…However, the genetic correlations between SCS and TBCS with PY and FY were of opposite signs, being negative for fat and positive for protein. Wasana et al (2015) reported negative genetic correlations between SCS and the PY (−0.04) and FY (−0.02), but with values close to zero; while Pritchard et al (2013) found positive genetic correlations between SCS and the PY (0.13) and FY (0.07). The reduced value of most of these correlations indicates only little association between the genes that increase these milk solids and genes that increase susceptibility to mastitis.…”