DATA on three Austrian Fleckviell breed associations in LAO Wei Austria, Upper Austria and Tirol regions were collected in the period from 1976 through 1982. The material consisted of 130039 female records for the first four lactations. Interval traits analyzed were age at first calving (AFC), age at second calving (ASC), days-open period (DO), days dry period (DP) and lactation length (LP), while the productive traits were 100- and 305-day lactation milk traits (kg milk, kg far and fat To). There was no systematic change in the estimates of heritability and genetic and phenotypic variances for interval traits studied over the First four lactations. Heritability estimates for interval measures in the different parities were generally very low ranging between 0.04 and 0.10, except for age at calving (037 to 0.39). Estimates of genetic correlations ranged between 0.32 to 0.44 and 0.37 to 0.47 for age at calving with DO and LP, respectively. High genetic and phenotypic relationships were observed between DO and LP (0.55 to 0.75) while negative correlations between DP and LP were obtained, of the order of - 0.2. Genetic correlations between DO or LP and 100 and 305- day milk and fat yields were mainly positive and of the order 0.3 to 0,5 according to the order of parity while negative estimates were found between all interval traits and fat% . In most cases negative genetic correlations were detected between DP and all milk traits in 100- and 305-day lactation. Phenotpic correlations were higher with 305-day lactation than with 100-day lactation. indicating the possibility of an effect of pregnancy. Phenotypic correlations between yield traits (milk and fat ) in both 100- and 305-day lactation and interval traits were positive and relatively low in different lactation while negative estimates with DP were observed . Far % in different lactations were phenotypically negatively correlated with interval traits studied.
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