An analysis of cow productivity traits in Pinzgauer cattle was carried out on 19754 first and second lactation records from 1614 sires, collected in the period from 1974 through 1983 in the valley pasture and mountain pasture Salzburg regions. Yields of milk, fat and protein at 100 and 305 days of lactation were the traits examined. The effect of age at calving, days open, and year-and-month of calving on these
traits were investigated. Age at calving affected (P < 0.05 or P < 0.01) most milk traits studied but no consistent pattern of such effects was observed. Age at calving did not account for as much variation in fat and protein yields as it did in milk yield. Milk traits studied increased linearly (P < 0.05 or P < 0.01) with the increase of days open. Year and month of calving exerted a pronounced effect (P < 0.05 or P <
0.01) on milk traits studied. There was an upward trend in all traits with year of calving. The highest occurence of calvings was in September and October. Factors for adjusting milk traits of Austrian Pinzgauer cattle for calving age and days open were constructed from smoothed curves of least-squares means of age at calving and days open classes.
Differences in age correction factors were inconsistent across traits in the first two lactations of Pinzgauer
cows in the valley pasture and alpage, while a consistent trend was observed for days-open encorrection factors. In spite of increased milk production with age of cow at calving, it is recommenkd,economically, to the Austrian dairy cattle breeders to bred their heifers and cows as early as possible.
The days open of 60 days for both lactations were suggested as optimum days open for attaining maximum production for Pinzgauer cattle in Austria. |
