Genetic parameters for longevity measures in Brazilian Holstein cattle using linear and threshold models

Abstract

The aim in this study was to estimate variance components and heritability of different longevity measures related to productive life and survival at a specified age, using linear and threshold models, to specify the more appropriate measure to express longevity in Brazilian Holstein cows. Production and reproduction records of Holstein cows were collected from 1991 to 2010, for cows born between 1987 and 2006. Variance components were obtained by restricted maximum likelihood (REML) for measures of productive life and a Bayesian analysis for survival measures. The heritability estimates for longevity measures ranged from 0.06 to 0.09, using the linear model and from 0.05 to 0.18 for traits using the threshold model. This suggests an inexpressive genetic gain using selection for these traits, whereas improvements in environmental factors which affect these animals may lead to greater phenotypic gains. Survival up to 48 months from first calving was the measureing point defined as the most appropriate to be included in future official genetic evaluations of Holstein cattle in Brazil.

Genetic parameters and trends for reproductive traits in Blanco Orejinegro cattle from Colombia

“…Concerning NCmax, there are no reports in this regard, especially in American creole cattle. However, Kern et al (2014), estimated longevity measures related to productive life and survival at a specified age in Brazilian Holstein cattle. These authors reported productive values up to 84 months of age (7 years), i.e., lower values than those found in the current study.…”

Breeding strategies for improving smallholder dairy cattle productivity in Sub‐Saharan Africa

“…Longevity is currently being considered in breeding goals for dairy cattle worldwide (Interbull, 2019). The heritability of the trait is often low (Kern et al., 2014; Musingi et al., 2018). In addition, an unfavourable genetic correlation between the longevity and production traits such as milk, fat and protein has been reported (Pritchard et al., 2013).…”

Evaluation of the Genetic Relationship between Longevity and Growth, Milk Yield and Fertility Traits in the Sahiwal Breed in Kenya

“…Measures of longevity related to productive life i.e. were defined alternatively as time between birth and last milking record in days (Long1), length of productive life or functional longevity (days) (Long2), number of lactations initiated (Long3), total number of days in lactation over all lactations (Long4) and total milk yield over all lactations, kg (Long5) [21]. Variance components, genetic and phenotypic parameters for longevity were estimated using a linear model using the expectation maximization method in WOMBAT [41] using a convergence criterion of 10 −9 .…”

“…The 95% confidence intervals were also wide. Heritability estimates for measures of longevity are dependent on breed [25] and method of analysis [49] and definition of longevity [5] [6] [21]. In general heritability estimates of longevity are low regardless of method of evaluation, breed or species [5] [36].…”