Studien zu Genotyp-Umwelt-Interaktionen beim Deutschen Schwarzbunten Niederungsrind

Summary

The aims of the present study were i) to analyse the genetic structure of the local black and white cattle breed (DSN), and ii) to analyse genotype by environment interactions based on defined herd parameter groups (geographic, environmental, phenotypic descriptors). The study considered 3688 DSN and 3599 HF cows from 46 herds keeping both breeds. Farms mostly reflected pasture based low input production systems. A multiple trait approach, i.e. defining same traits in different clusters as two different traits, was applied to prove genotype by environment interactions based on genetic correlation estimates. Genetic correlations between low heritability functional traits were lower than for production traits. Especially for functional traits such as somatic cell score (SCS) and fat to protein ratio genetic
correlations remained below rg= 0.80 and showed possible genotype by environment interactions.