Estimation of cytoplasmic effects for production and reproduction traits in Austrian Simmental cattle.
Abstract
According to the important cellular functions of mitochondria, which are at least partly caused by their own genes (mt-DNA), a substantial contribution to variation of performance traits through mt-DNA can be expected. The objective of the present research was the evaluation of cytoplasmic gene effects in Simmental cattle. GLS-estimation and hypothesis testing of the cytoplasmic lineage effects for different dairy, beef and reproduction traits using an appropriate animal model was carried out with data of an experimental herd. Estimates of the relative proportion of cytoplasmic to phenotypic variance were within the range of 0 and 8 %. No significant lineage differences (P > 0.05) could be found for any of the dairy and reproduction traits, whereas the existence of cytoplasmic effects concerning the trait meat content (multiple P-value < 0.05) as well as, with some reservations, proportion of valuable cuts and chest depth (individual P-values < 0.05) achieved statistical significance. For field data analysis, data of the Austrian milk recording scheme were used. Variance components were estimated using a REML-procedure based on an animal model. Estimated heritabilities due to cytoplasmic effects ranged from 0.0 to 4.6 %. Estimates were less than 0.1 % for all milk production traits (milk yield, FCM, fat and protein content) with exception of milk yield and FCM of the 1st lactation (2.0 and 2.3 %). The estimated cytoplasmic heritabilities for persistency (3.2, 3.8 and 2.6 %) and days open (2.9, 1.8 and 2.3 %) of the first three lactations and for effective and adjusted length of productive life (4.6 % each) were all statistically significant (multiple P-value < 0.05).
keywords cattle cytoplasmic inheritance animal model parameter estimation Simmental cattle
Publikationen
Field data analysis of cytoplasmic inheritance of dairy and fitness-related traits in cattle.
Autoren: Schnitzenlehner, S., Eßl, A. Jahr: 1999
Journal articles