INTRODUCTION


 Interest in increasing beef production from crossbreeding has focused
attention on the F1 female because of the high productivity associated
with maternal heterosis. Comparisons among F1 reciprocal crossbred
cows are desirable in order to determine if differences in their producing
ability can be attributed to the breed of their dam. The purpose of this
paper is to compare the performance of reciprocal F, crossbred females
as to dam breed for both reproduction and production traits. The
Fr females represented all combinations of the Angus, Brahman, and
Charolais breeds. These breeds represent three divergent breed types
with respect to size and adaptation to the Florida environment (Peacock
et al., 6).


 METHODS AND PROCEDURES

 The data reported here were obtained at the ARC, Ona, over a 7-year
period from a project in which Angus (A), Brahman (B), and Charolais
(C) bulls were each bred to F, (AB, BA*), F1 (AC, CA*), and F, (BC,
CB*) cows of Angus, Brahman, and Charolais breeds. Bulls were put out
March 1 and removed from the herd June 1 each year. The nutritional
plane of herds varied among years, but the average could be considered
fair to good. Herds were grazed on bahiagrass and Pangola digitgrass
year-round, with molasses supplement or a cottonseed meal-citrus pulp
mixture (1:4 ratio) at 5 pounds per head daily for approximately 90 days
during late winter and early spring. Weaning data on calves and data on
pregnancy status of cows were collected the latter part of August each
year. A total of 21 sires were used (7 of each breed) during the 7-year
period. Heifers were first exposed to bulls at 2 years of age.
 The data analyzed, utilizing least-squares procedures as outlined by
Harvey (1), were the individual records for pregnancy, calf survival, calf
age at weaning, weaning weight, estimated 205-day weight, and cow
weight.


 RESULTS AND DISCUSSION
 The variance analyses for traits measured are presented in Table 1.
Effects such as year, sex, dam age, and in this particular study, sire
breeds, were included in the analysis to adjust for F, dams effects.



*Sire breed is written first in F, combinations.