Aufzucht und Spermaproduktion bei Jungbullen unter Stationsbedingungen in Finnland

Authors

• U. Uusisalmi Institut für Haustierzüchtung, Universität Helsinki, Finnland
• M. Kallio Institut für Haustierzüchtung, Universität Helsinki, Finnland
• G. Klautschek Sektion Tierproduktion, Universität Rostock, DDR
• M. Varo Institut für Haustierzüchtung, Universität Helsinki, Finnland

DOI: https://doi.org/10.23986/afsci.72940

Abstract

A study was made of the growth fo young A. I. bulls of Ayrshire and Finncattle breeds at performance testing stations during the first year and, subsequently, of the quantity and quality of their semen production at A. I. stations in the second year. The heritabilities of semen production characteristics, and the correlations between results of performance testing and characteristics of semen production were determined. 47 Ayrshire bulls (progeny of 10 sires) were reared at the Humppila Performance Testing Station, and 17 Finncattle bulls (progeny of 5 sires) at the Maunula Performance Testing Station, in 1967–69. The bulls were weighed at intervals of 30 days from the age of one month to the age of one year. Five different body measurements were also taken, at the age of 180 days and at the age of 365 days. Their semen production characteristics were measured at A. I. stations (Salpausselkä und Uusimaa & Kymi) from the age of 12 months to the age of 24 months. The data on semen production for at least 8 months were required for each bull. The following characteristics were recorded: semen production per month; approved semen per month, per collection day and per ejaculate: aproved semen per collection day and per ejaculate; semen density: approved semen in percentages per month; approved semen in percentages per collection day. The following results were obtained for the values corrected for age, number of collection days and number of ejaculations. There were no statistical differences in the quantity and quality of semen between the two breeds (Ay and Fc). The semen production of the progeny groups of the sires differed very significantly in every individual characteristic pertaining to semen production. The individual young bulls likewise differed significantly or very significantly from one another in their semen production. It is thus possible to improve semen production by means of selection. The Ayrshire breed gave the h2 value of 0.42 for semen production per month, 0.40 for semen production per collection day, and 0.47 for semen production per ejaculate. The weight development, the growth rate and the bodily measurements of the performance testing phase correlated positively with the semen production. The young bulls that did well at the performance testing stations (weight development and growth rate good) also produced a great deal of semen during the test phase. Thus a selection based on growth results indirectly leads to improved semen production of the bull.