430 
GENETICS: W. E. CASTLE 
Since this agrees closely with Roberts'^ finding for the breed in general, 
it will be assumed to hold for the entire group of 25 cows. On this 
basis the average butter-fat production for the Holstein cows in their 
first lactation period would be 261 pounds. 
TABLE 1 
Milk and Butter-Fat Production or Fi Cows 
cow 
FIRST 
LACTATION 
PERIOD 
SECOND LACTATION PERIOD 
Age 
Time 
Total 
pounds of 
milk. 
Fat 
Total 
fat 
Age 
Time 
Total 
pounds of 
milk 
Total 
fat 
months 
per cent 
months 
*Alice 
2\ 
8,070 
4.0 
323 
Annie 
2f 
9 
(5,460) 
4.3 
235 
^1 
7,536 
324 
3^ 
10 
(6,297) 
4.0 
252 
Blackfoot 
2i 
7,755 
4.1 
318 
4i 
10,125 
415 
*Daisy 
3i 
11 
(7,661) 
4.3 
329 
4i 
9,375 
403 
21 
7,908 
4.2 
332 
4 
11,538 
484 
Ellen 
9 
(6,096) 
4.2 
256 
41 
lU 
(8,949) 
376 
Emerald 
2\ 
8,517 
4.1 
349 
Emma 
21 
7 
(3,768) 
4.0 
151 
3f 
(7,080) 
283 
Fairiel 
2\ 
4,740 
4.6 
218 
Fanny 
2\ 
9 
(5,325) 
4.0 
213 
3f 
9,135 
365 
*Freckles 
^6 
7,773 
4.0 
311 
^1 
8,340 
333 
* Grace 
3 
11 
(5,796) 
4.3 
249 
2\ 
7,881 
4.3 
338 
Jane 
2\ 
7,809 
4.5 
351 
4| 
11 
(8,646) 
389 
Julia 
21 
101 
(6,498) 
4.6 
279 
A 
0,000 
*Kate 
2f 
7,689 
4.5 
346 
Lavaine 
2| 
5,550 
3.7 
205 
*Lilvene 
^6 
11 
(6,000) 
4.1 
246 
Lilac 
2i 
11 
17,542J 
'} 0 
3.8 
286 
3i 
6,489 
246 
*Mary 
2f 
(8,199) 
4.0 
327 
41 
11 
(8,871) 
355 
Nancy 
4,899 
4.3 
210 
Peach 
^3 
8,508 
3.8 
323 
Pearl 
2\ 
7,446 
3.7 
275 
Peggy 
2h 
6,507 
3.8 
247 
*Ruby 
91 
9 
(4,440) 
3.7 
164 
Sapphire 
^1 
6,618 
4.0 
264 
91 
101 
(6,168) 
4.1 
252 
Sylvene 
91 
6,075 
4.0 
243 
Tessa 
2h 
lU 
(5,700) 
4.4 
250 
7,710 
339 
Twisk 
2h 
6,252 
3.8 
237 
2.61 
11.14 
6,612 
4.08 
270 
3.88 
8,663 
363 
In table 3 are summarized the milk production records of 8 pure-bred 
registered Guernsey cows which also formed a part of the Bowlker herd. 
They calved for the first time at an average age of 2.7 years and gave 
in a first lactation period of from seven and one-half to twelve months 
