TRANSMITTING ABILITY OF HOLSTEIN-FRIESIAN SIRES 3 
Table 1. — Ages and per cent used in calculating production records to maturity 
Age, calculated to nearest whole month 
Mature 
record 
equiva- 
lent 
Age, calculated to nearest whole month 
Mature 
record 
equiva- 
lent 
Per cent 1 
70.0 
72.5 
75.0 
77.5 
80.0 
82.5 
85.0 
3% and under 4 years 
Per cent 1 
87.5 
4 and under 4}4 years. 
90.0 
4J4 and under 4H years. 
92.5 
4 1/6 and under 4%4 years 
95.0 
4% and under 5 vears 
97.5 
5 years and over 
100.0 
33^ and under 3% years 
1 The percentages used for calculating records to maturity correspond very closely to the percentage 
differences of the average production in the various classes for the Holstein-Friesian breed. Aside from 
the corrrection for differences in age, other factors that might cause variation between the records of the 
daughters and their dams, such as number of times milked per day, were not considered, as the information 
is not available. 
PRODUCTION RECORDS OF DAUGHTERS AND THEIR DAMS 
Table 2 shows detailed production records of the daughters of these 
23 sires, together with the production of their dams; the dam's record 
in every case is given on the same line as that of her daughter. 
Averages are stated also, to facilitate comparison. Other figures show 
the average quantity of milk, percentage of butterfat, and pounds 
of butterfat by which the daughters exceed their dams or are exceeded 
by their dams. Plus and minus signs indicate excess or deficiency of 
the average daughter's performance compared with the average dam's 
performance. 
The object of the investigation was to study the hereditary trans- 
mission of production, not to point out the good or the poor sires of the 
breed; hence the sires in these lists have been designated by letter 
and not by name. The records are arranged in the order of the 
daughters' butterfat records, beginning with the highest record. 
Table 2. — Production records of daughters and their dams 
SIRE A 
Daughters 
Darns 
Milk 
Butterfat 
Milk 
Butterfat 
1 . 
Pounds 
22, 757. 
22, 515. 2 
21, 260. 8 
16, 266. 
15, 079. 7 
Per cent 
3.43 
3.21 
3.20 
3.47 
3.60 
Pounds 
779.7 
723.1 
678.6 
564.7 
543.4 
Pounds 
10, 928. 3 
18, 290. 1 
13, 285. 
17, 287. 3 
12, 533. 4 
Per cent 
3.30 
3.03 
3.40 
3.32 
3.12 
Pounds 
361.4 
2 
554.7 
3 
451.8 
4 
575.0 
5 
391.8 
Average of 5. _ 
19, 575. 7 
+5,110.9 
+35.3 
3.36 
+0.13 
+4.02 
657.9 
+191. 
+40.9 
14, 464. 8 
3.23 
466.9 
Increase (+) of daughters over dams 
Per cent increase 
Four daughters exceeded dams in milk. 
Four daughters exceeded dams in butterfat. 
Four daughters exceeded dams in percentage of butterfat. 
