Record Details

The comparison of two methods of evaluating inheritance of milk production of dairy sires

ScholarsArchive at Oregon State University

Field Value
Title The comparison of two methods of evaluating inheritance of milk production of dairy sires
Names Srinives, Supote (creator)
Bogart, Ralph (advisor)
Date Issued 1965-11-12 (iso8601)
Note Graduation date: 1966
Abstract The production records used were all converted to a comparable
based, 305 day lactation period, two times a day milking, and
mature equivalent (305 days-2-x-ME) of 71 cows from four Holstein
bulls and 59 cows from four Jersey bulls were used for the study.
The Equal Parent Index, Regression Index and Herd-Mate Average
were calculated for each of eight bulls using five daughters and using
all daughters. The study consisted of data collected from 1957 to
1965 in Oregon State University dairy herd.
The use of records from five randomly selected daughters
gave as good an estimate as was obtained when the records of all
daughters were used for indexing dairy bulls. In comparison between
the Regression Index and Herd-Mate Average, neither method
gave a clear-cut estimate; the Regression Index tended to give an
overestimate while the Herd-Mate Average tended to give an underestimate
of a bull's transmitting ability. All indexes except the Herd-Mate Average for Holstein bulls
failed to give an accurate estimate of the average actual production
of the daughters.
There was a significant difference between the Holsteins and
Jerseys for both milk and butterfat production. Also, the three
methods differed significantly from one another in the estimates of
transmitting ability of sires.
Genre Thesis/Dissertation
Topic Cattle -- Breeding
Identifier http://hdl.handle.net/1957/47946

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