Genetic Parameters of Postnatal Mortality in Danish Holstein Calves

Abstract

The objective of this study was to estimate genetic parameters of postnatal mortality (PM) in dairy cattle. Data originated from 841,921 Danish Holstein calves. Four binary traits of mortality were considered: D1-14, D15-60, D61-180, and D1-180 with numbers indicating the period of risk in days after birth. The unadjusted frequency of D1-14, D15-60, D61-180, and D1-180 were 0.027, 0.018, 0.020, and 0.066, respectively. A linear sire-model was fitted to the data, and average information-REML was used to estimate (co)variance components. Estimates of direct heritabilities for the four mortality traits ranged from 0.001 to 0.008 but were all significant. D61-180 and D1-180 had the highest direct heritabilities. Maternal heritabilities were very low, ranging from 0.0002 to 0.0015 and significant for D1-14 and D1-180 only. The direct genetic correlation between D1-14 and D15-60, between D15-60 and D61-180, and between D1-14 and D61-180 was 0.73, 0.54, and 0.34, respectively. It indicates that different genes are responsible for early PM (D1-14) and late PM (D61-180). When D61-180 was treated as a different trait for females, males not transferred, and transferred males, the direct heritability was 0.004, 0.008, and 0.034, respectively, but the direct genetic correlations between these three traits were very high. If transfers of calves are getting more common, the importance of including PM in a breeding program will increase, as the genetic variation of PM was considerably higher for transferred calves than for calves that were not transferred.

Stillbirths in Holstein heifers – some results from Swedish research

“…from USA, Denmark and Holland show stillbirth rates of 10-13% in Holstein heifers comparable with those reported in Sweden (e.g. [3][4][5]). …”

Mortality in Austrian dual purpose Fleckvieh calves and heifers

“…Gulliksen et al (2009) reported a mortality rate of 3.7% in the first year of life in Norwegian dairy herds, while Svensson et al (2006) observed 3.1% of calves dying up to an age of 90 days in southwestern Swedish farms. In Denmark, 6.6% of Holstein calves (Hansen et al, 2003) and a rather alarming proportion of 12.5% of Jersey calves (Norberg, 2008) died up to an age of 180 days. Dystocia, respiratory diseases or pneumonia and diarrhoea are frequently mentioned as the most important factors influencing mortality in calves and heifers (e.g.…”

“…The aim of this study therefore is to explore the genetics of calf and heifer mortality in Austrian Fleckvieh (dual purpose Simmental) by (1) defining relevant periods for juvenile survival, as evidence from earlier studies (Hansen et al, 2003) suggests that survival of calves and heifers is different at different stages of their life and may therefore be controlled by different genes; (2) comparing different methods (linear and threshold models, sire and animal model) for estimating variance components and genetic parameters; and (3) implementing a genetic evaluation of the current Austrian Fleckvieh population.…”

“…Losinger and Heinrichs, 1997;Svensson et al, 2006;Gulliksen et al, 2009). Among the few genetic studies Hansen et al (2003) analyzed genetic parameters of postnatal mortality of Danish Holstein calves aged up to 180 days using linear models. Direct heritability for postnatal mortality was very low ranging from 0.001 (day 15 to 60) to 0.008 (day 61 to 180).…”

Genetic and non-genetic effects on calf vigor at birth and preweaning mortality in Nellore calves

“…Preweaning mortality is an important economic component of farming systems since it reduces the number of animals available for sale (Østerås et al, 2007), compromises animal well-being (Hansen et al, 2003), and reduces the number of animals available for selection as well as genetic progress (Fuerst-Waltl & Fuerst, 2010;Meyer et al, 2001). …”