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However, as the record is at present, the calves from crossbred cows sired by
either purebred parent, as shown in groups 8, 9 and 10, are heavier than their
crossbred parents at the same age, shown in groups 4, 5, 6 and 7. When these
crossbred cows are mated to crossbred bulls of the same parent stock the resulting
progeny, group 12, are not as heavy as their dams (groups 4 and 5). Crossbred
sires mated to Devon cows produced larger calves than from crossbred cows, shown
in groups 11 and 12.

 In the Angus-Brahman crossbreeding, no crossbred sires have been used,
and in the data included in this table there were no back-crosses to the Angus.
Since all of the cows of Angus breeding are being bred to Angus sires, there are
Angus back-crosses among the younger animals, whose records will be included in
a future report.


 Other Breeding Plans. Questions are frequently asked relative to the
merits of a "rotational" breeding program involving three breeds. Facilities
at this Station preclude such a program. The "Beef master" is an example of a
crossbred produced from three breeds, Hereford, Shorthorn and Brahman. Value
of such a rotational program would be difficult to measure but could produce
good crossbred cattle.

 A large portion of the range cows of Florida have been produced
 through a "grading up" program from native cows mated to Brahman sires. Suc-
 cessive generations sired by Bulls of one breed produce cattle with the charac-
 teristics of the purebred but additional improvement is not so rapid after the
 first two or three generations. The use of selected crossbred sires in such
 herds may be a good procedure. The record shown in group 11 in the table indi-
 cate that crossbred sires on purebred cows produce superior calves.

 "Grading up" is the recognized program of development for the Santa
 Gertrudis breed. It is successful because it is supported by thorough culling
 and selection plan.

 No breeding plan can be carried out successfully without rigid
 selection, adequate feed, good management and high quality foundation stock.


 Recommendation. The present records from this crossbreeding program
 indicate that the "criss-cross" breeding program(described in Program 1) can
 be recommended as a system to follow in South Florida. Some of the advantages
 of such a breeding program are:

 1. It produces calves that are larger than the purebred parents.
 2. It is simple and can be workable on many ranches.
 3, It creates a market for good purebred bulls.
 4. It permits early castration of calves since no crossbred bulls
 will be selected for use as herd sires*






 EES 57-10
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