Genetic parameters for female fertility and milk production traits in first-parity Czech Holstein cows

Abstract

ABSTRACT:The aim of this study was to estimate genetic parameters for female fertility and production traits in first-parity Czech Holstein cows and to quantify the effect of using this information on the accuracy of a selection index in seven different scenarios. In order to estimate genetic (co)variance components, the DMU software running an AI-REML algorithm was used. The analyses were made using a series of bivariate animal models. The pedigree included 164 125 animals and it was set up using a pruned animal model design. The present study included the following female fertility traits for the first lactations: calving to the first insemination (CF), days open (DO), calving from the first to the last insemination (FL), and milk production traits: milk production (MLK), kg of fat (FAT), and kg of protein (PROT). The heritability for all the investigated fertility traits was low and close to 0. Moderate heritabilities for production traits ranging from 0.20 (MLK) to 0.23 (PROT) were estimated. The strongest unfavourable correlation was found between PROT and DO (0.49). Other estimated correlations between fertility traits and production traits were moderate, ranging from 0.26 to 0.41. The results of this study evidence that cows with the poorest genetic potential for reproductive performance are those having high genetic potential for milk production and milk components. The results also show that the number of days from calving to new pregnancy depends on the production level. Seven investigated scenarios using selection index theory show a clear trend for increasing accuracy when more fertility traits were added as well as when higher numbers of daughters with information on reproduction traits per sire were available.

Genetic relationship of functional longevity with female fertility and milk production traits in Czech Holsteins

“…These are higher than previous estimates from Czech data by Dědková and Wolf (2001), who found heritabilities of 0.28, 0.24, and 0.25, and higher than those of Zink et al (2012), who reported 0.21, 0.21, and 0.23 for MY1, FY1, and PY1, respectively.…”

“…These estimates are slightly higher than those of Zink et al (2012), who reported 0.04, 0.04, and 0.03 for CFI1, DO1, and FLI1, respectively, for Czech Holsteins. Current results are, however, concurrent with other recent research.…”

Effect of bull, diluter and LDL-cholesterol concentration on spermatozoa resistance against cold shock

“…bull semen, sperm survival, cold shock, extender, LDL cholesterol Fertility of dairy cows has declined over the past fi ve decades as milk production per cow has increased (Zink et al, 2012;Walsh et al, 2011). The issue of cattle fertility was intensively studied in recent years from cow point of view and eff ects on their reproductive performance (Doležalová et al, 2013;Roche et al, 2011;Hanuš et al, 2010;LeBlanc et al, 2010).…”

The yield and cell viability of bovine <i>in vivo</i> recovered embryos in relation to season of flushing

“…Zink et al (2012) determined the genetic parameters for female fertility in relation to the accuracy of the selection index under different scenarios, when Šafus et al (2005) stated the necessity of incorporating breeding values for reproduction traits into the Czech selection indexes for the Holstein breed based on the BV for milk production. The average BV in dairy cows flushed during individual seasons fluctuated only within the range of 69-293 kg.…”