BUTTERFAT PRODUCTION OF CATTLE 
15 
Table 17. — Comparison of average initial and retest records of Jerseys having 
initial records made at age of 5 years (class A and class A A records) 
Num- 
Average initial 
butterfat rec- 
ord made at 5 
to b}/ 2 years old 
Average reentry records made at ages shown in 
these columns by same cows as initial records 
shown in column at left (pounds of butterfat) 
In- 
crease 
due to 
age 
Portion of re- 
entry record 
due to de- 
velopment 
Average 
due to 
develop- 
ment for 
this 
group 
ber 
of 
cows 
to 
c 
o 
o 
o 
00 
o 
5b 
o 
00 
o 
3s' 
c 
03 
© 
c 
5-. 
© 
q 
C 
o 
o 
o 
O 
5 
co 
c 
o 
2| 
26 
35 
17 
12 
8 
8 
9 
3 
2 
1 
Pounds 
456 
477 
452 
497 
434 
451 
532 
444 
422 
498 
384 
r ,0K 
Pounds 
15 
16 
15 
17 
14 
15 
17 
15 
14 


3 
3 
3 
3 
3 
3 
3 
3 
-13 
-14 
-11 
-13 
-37 
Pounds 
37 
63 
70 
39 
127 
77 
118 
95 
-26 
90 
145 
59 
60 
82 
69 
30 
31 
-12 
-45 
52 
144 
190 
-11 
182 
P.ct. 
7.3 
11.3 
13.0 
7.1 
22.1 
14.2 
17.7 
17.1 
-6.3 
15.3 
27.4 
11.3 
10.5 
14.9 
12.2 
6.2 
5.4 
-2.4 
-9.1 
9.6 
21.8 
31.3 
-2.3 
36.0 
Per cent 
Wifi 
-..!-- 
• i 
537 
i 
553 
=----- 
575 
543 
11.7 
667 
554 
410 
588 
529 
520 
Made at 5}4 to 
6 years old 
36 
24 
20 
19 
458 
510 
467 
495 
452 
536 
508 
536 
503 
531 
429 
495 
361 
57S 
552 
567 
485 
1 
570 
5 
499 
11 1 
I 
494 
3 
542 
2 
661 

608 
3 
471 
506 
1 
1 
1 
Table 18. — Comparison of average initial and retest records of Jerseys having 
initial records made at age of 6 years (class A and class A A records) 
Number 
Average initial 
butterfat record 
made at 6 to 6% 
years old 
Average reentry records made at 
ages shown in these columns by 
same cows as initial records shown 
in column at left (pounds of but- 
terfat) 
In- 
crease 
due to 
age 
Portion of re- 
entry record 
Average 
due to 
develop- 
of cows 
o 
00 
o 
00 
o 
CO 
o 
o 
oo 
o 
03 
o 
c 
© 
o 
o 
o 
I 
c 
a 
c 
O 
CI 
o 
lO 
due to de- 
velopment 
ment for 
this 
group 
Pounds 
494 
523 
520 
453 
472 
464 
415 
408 
509 
604 
549 
548 
Pounds 







-13 
-16 
-19 






-19 
-14 
• -57 
Pounds 
55 
25 
45 
64 
85 
98 
309 
-19 
202 
-133 
67 
28 
-33 
42 
-7 
35 
277 
-30 
30 
P.ct. 
10.0 
4.6 
8.0 
12.4 
15.3 
17.4 
42.7 
-5.1 
29.1 
-29.4 
12.9 
4.7 
-6.2 
7.5 
-1.7 
6.9 
32.5 
-7.9 
6.0 
Per cent 
23 
565 
10 
4 
517 
557 
9.S 
3 
562 
1 
724 
376 
4 
- ... 
...| . 
695 
452 
... 
1 
... 
519 
Made at 6H to 7 
years old 
25 
452 
563 
563 
518 
423 
473 
594 
425 
529 
14 
591 
2 
530 
8 
560 
2 
416 
[ 8.0 
1 
508 
1 
852 
1 
381 
1 
502 
J 
