No CrossRef data available.
Published online by Cambridge University Press: 27 March 2009
1. Station progeny tests of twenty-four Ayrshire and twenty-two Friesian bulls were carried out by the British Oil and Cake Mills Ltd. at two centres in Britain between 1953 and 1961. The tests followed the Danish pattern: groups of ten to seventeen daughters were brought to the station approximately 6 weeks before first calving and milked under standardized conditions for an average of 270 days.
2. The place of the station system in modern dairy practice in Britain and abroad was discussed.
3. Earlier results had suggested that milk yield, butterfat percentage, S.N.F. percentage, milking rate and conception interval should be taken into account in a progeny test.
4. Correlations were calculated between the bulls 305-day field ratings for milk yield and fat percentage and their 90- and 270-day station assessments. Possible reasons for the discrepancies were investigated.
5. The selection system employed did not appear to lead normally to the choice of heifers whose dams' milk yield or fat percentage differed from the recorded averages for the breed. In two groups of special cases, deviations were apparent but the effect on the accuracy of the station test was shown to be small. It was concluded that bias due to maternal genetic variation was unlikely to be serious in the general case.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.