August 1976
Crossbreeding Cattle for Weaning
and Feedlot Performance in
South Central Florida
F. M. Peacock, M. Koger, W. G. Kirk, and J. R. Crockett
." --b"
Agricultural Experiment Stations
Institute of Food and Agricultural Sciences
University of Florida, Gainesville
J. W. Sites, Dean for Research
N
Bulletin 782
lay
CROSSBREEDING CATTLE FOR WEANING AND
FEEDLOT PERFORMANCE IN SOUTH
CENTRAL FLORIDA
F. M. Peacock, M. Koger, W. G. Kirk, and J. R. Crockett
Mr. Peacock is Associate Animal Husbandman, Agricultural Re-
search Center, Ona; Dr. Koger is Animal Geneticist, University of
Florida, Gainesville; Dr. Kirk is Animal Scientist Emeritus, Agri-
cultural Research Center, Ona; and Dr. Crockett is Associate Ani-
mal Geneticist, Agricultural Research and Education Center, Belle
Glade.
This public document was promulgated at an annual cost
of $673.50 or a cost of 11 per copy to provide information
on weaning and feedlot performance of various crosses of
the Brahman and Shorthorn breeds in south central Florida.
CONTENTS
INTRODUCTION ---....- .....-- ..-..-- ....-...-..............--- -...--....----- 1
MATERIALS AND METHODS .....--....-...........-..-...-.---------- 1
EXPERIMENTAL RESULTS AND DISCUSSION -....--..-.. 3
Preweaning Performance .........................------------------ 3
Age of Calf at Weaning -...---. ............------------............ 3
Weaning Weight and Estimated 205-day Weight .... 3
Condition Score -..--........--....-..-... -- ....--------- 3
Feedlot Performance ..----........--- .....-...........------- 5
Daily Gain .--~. ~-...... ---............... ...-------------- 5
Carcass Grades .............-----------..... ------------- 7
Dressing Percent .....................................----------- 7
Feed Per 100 Pounds Gain .-...---...................----------.. 7
SUMMARY AND CONCLUSION .--...........................---------- 8
LITERATURE CITED ...-....---......----- ..............-- -- ...... 10
CROSSBREEDING CATTLE FOR WEANING AND
FEEDLOT PERFORMANCE IN SOUTH
CENTRAL FLORIDA
F. M. Peacock, M. Koger, W. G. Kirk and J. R. Crockett
All phases of the beef production cycle are influenced by en-
vironmental factors and genetic attributes of the cattle. The
task of the beef cattle breeder has been to develop breeds or
breed combinations that will perform economically under the
conditions prevailing. Genetic adaptation is especially important
under unfavorable conditions. The most rapid method for
achieving genetic adaptability and production characteristics is
through judicious crossbreeding of adapted and potentially pro-
ductive breeds (Koger, 10)1.
For maximum efficiency of beef production, the breeding sys-
tem must maintain a productive cow herd and produce offspring
that perform economically in the post-weaning growing and
finishing phase of the production system. The purpose of this
bulletin is to present weaning and feedlot performance data from
various crosses of the Brahman and Shorthorn breeds in semi-
tropical south central Florida.
MATERIALS AND METHODS
The data used in this study were from a breeding project de-
signed to compare Brahman, Shorthorn, and various Brahman-
Shorthorn crosses. The data included in this paper were from
five calf crops.
The calves were from five breed groups of cows mated to pro-
duce crossbred calves. Brahman (B), % Brahman--1/ Shorthorn
(B3S1), and firstcross (Fi) cows were mated to Shorthorn bulls.
Shorthorn (S), 3/ Shorthorn-1/4 Brahman (SaB,), and Fi cows
were mated to Brahman bulls (Figure 1). Approximately 30 cows
annually were included in each of the six mating groups. One-
third of the cows in each breed group were maintained on native
range, one-third on a combination of native range and improved
pasture, and one-third on highly improved clover-grass pastures.
The cattle were bred in a restricted season of 105 days from
March 15 to July 1. All calves were weaned at the same time in
early September, at an average age of 219 days.
Individual calf data were recorded annually for age of calf,
condition score, 205-day weight, and weaning weight. Sources of
1 Figures in parentheses refer to Literature Cited.
CROSSBREEDING CATTLE FOR WEANING AND
FEEDLOT PERFORMANCE IN SOUTH
CENTRAL FLORIDA
F. M. Peacock, M. Koger, W. G. Kirk and J. R. Crockett
All phases of the beef production cycle are influenced by en-
vironmental factors and genetic attributes of the cattle. The
task of the beef cattle breeder has been to develop breeds or
breed combinations that will perform economically under the
conditions prevailing. Genetic adaptation is especially important
under unfavorable conditions. The most rapid method for
achieving genetic adaptability and production characteristics is
through judicious crossbreeding of adapted and potentially pro-
ductive breeds (Koger, 10)1.
For maximum efficiency of beef production, the breeding sys-
tem must maintain a productive cow herd and produce offspring
that perform economically in the post-weaning growing and
finishing phase of the production system. The purpose of this
bulletin is to present weaning and feedlot performance data from
various crosses of the Brahman and Shorthorn breeds in semi-
tropical south central Florida.
MATERIALS AND METHODS
The data used in this study were from a breeding project de-
signed to compare Brahman, Shorthorn, and various Brahman-
Shorthorn crosses. The data included in this paper were from
five calf crops.
The calves were from five breed groups of cows mated to pro-
duce crossbred calves. Brahman (B), % Brahman--1/ Shorthorn
(B3S1), and firstcross (Fi) cows were mated to Shorthorn bulls.
Shorthorn (S), 3/ Shorthorn-1/4 Brahman (SaB,), and Fi cows
were mated to Brahman bulls (Figure 1). Approximately 30 cows
annually were included in each of the six mating groups. One-
third of the cows in each breed group were maintained on native
range, one-third on a combination of native range and improved
pasture, and one-third on highly improved clover-grass pastures.
The cattle were bred in a restricted season of 105 days from
March 15 to July 1. All calves were weaned at the same time in
early September, at an average age of 219 days.
Individual calf data were recorded annually for age of calf,
condition score, 205-day weight, and weaning weight. Sources of
1 Figures in parentheses refer to Literature Cited.
Brahman
Shorthorn 5/8 Brahman
I 3/8 Shorthorn
Shorthorn 3/4 Shorthorn 8 Shorthorn
(Sire) 1/2 Brahman 1/4 Brahman
Brahman 1/2 Shorthorn
(Dam)
Shorthorn
Brahman 5/8 Shorthorn
Brahman 3/4 Brahman 3/8 Brahman
(Sire) 1/2 Brahman 1/4 Shorthorn
1/2 Brahman
Shorthorn 1/2 Shorthorn
(Dam)
Figure 1. Breeding techniques to produce reciprocal progeny.
variability included year, mating group (sire x dam), pasture
program, sex, age of dam, and first order interactions. Least
squares procedures were employed for the analysis as outlined
by Harvey (8).
Steer calves from three calf crops were fed by individual
breed groups for an average of 191 days to evaluate their feedlot
performance. Breeding groups included: BsS1; B5S3; Fi; SB3S;
and S3B1. Seven calves of each breed group were placed in the
feedlot immediately after weaning.
The ration consisted of a mixture composed of 20 parts 41%
cottonseed meal, 40 parts citrus pulp, 21 parts ground snapped
corn, 12 parts corn feed meal, 5 parts alfalfa, and 1 part mineral,
plus 2.5 pounds of Pangola digitgrass hay daily per steer. Calves
were fed once each day. At the end of each feeding trial they
were trucked a distance of 76 miles and slaughtered at Lykes
Brothers Meat Packing Plant, Tampa, Florida. Warm carcass
weights were obtained and carcasses were graded after 48 hours
in the cooler.
Carcass weights were converted to a chilled basis by shrinking
hot weights by 2.5%. Because of variations among groups in
dressing percentages, gains were calculated on both an actual
and adjusted basis. Actual weight of calves was used as the
initial weight. Final liveweights were adjusted to obtain a con-
stant dressing yield of 60% as outlined by Baker (1) where
adjusted final weight = chilled carcass weight .60. Adjusted
final weights were used in calculating final average daily gains
and feed conversion.
Feedlot performance data were analyzed by analysis of vari-
ance and tested for significance by Duncan's Multiple Range Test
(7).
EXPERIMENTAL RESULTS AND DISCUSSION
Preweaning Performance
Mean squares and levels of significance for age at weaning,
weaning weight, 205-day weight, and condition score of calves
are presented in Table 1. Least squares means for age at wean-
ing, weaning weight, 205-day weight, and condition score of
calves by breed group are shown in Table 3.
Age of Calf at Weaning
Age of calf at weaning is an important production trait, in-
fluencing the weight and value of calf produced. It was analysed
as a production trait in this study in addition to using it for esti-
mating weight at a constant age of 205 days. Difference in age
at weaning for breed groups of calves were non-significant.
Weaning Weight and Estimated 205-day Weight
Estimated 205-day weight is a measure of growth rate while
weaning weight reflects both growth and age at weaning. The
breed-group differences in this study were similar for the two
traits (P<.01).
The lowest calf weights were for calves out of Shorthorn cows
(409 pounds). The highest weights (479 pounds) were for calves
out of Fi cows mated to Brahman bulls. The remaining weights
were 440 pounds for B5S3 calves, 448 pounds for S5sB calves,
S449 pounds for Fi calves from Brahman cows, and 456 pounds
for S3B1 calves.
Variations in weaning weights in this study (all calves being
crossbred) were mainly the result of maternal influences ex-
hibited by the different cow groups. Purebred Shorthorn cows
produced calves with the lowest average weaning weight and F1
cows the highest. Koger et al. (11) showed that estimated addi-
tive breed and Fi heterosis effects for maternal influence was
similar to that for direct effects expressed in the calf for calf
weights and condition score.
Condition Score
Weaning condition score is a measure of fatness, being posi-
Table 1. Mean squares and levels of significance for age at weaning, weaning weight, 205-day weight, and condition score of
calves.
Mean Squares
Source of Variability D.F. Weaning Age Weaning Weight 205-day Weight Condition Score
Years 4 5,538** 28,606** 64,339 36.28"*
Pasture 2 19,241"* 705,705** 310,788** 241.00**
Breed 5 1,659 42,980** 48,991 14.61**
Sex 1 6 95,105"* 92,686** 27.70**
Error 590 849 4,178 2,048 1.31
* P<.01
SP<.05
tively related to maternal influence of the dam. Variations in
condition scores among breed groups of calves were highly sig-
nificant. Calves with the highest condition score were the SsB1
group out of Fi cows with a value of 10.3 and the lowest were Fi
Scales out of Shorthorn cows with a score of 9.2. The remaining
groups varied from 9.3 to 10.0.
Feedlot Performance
Daily Gain
The analysis of variance and levels of significance for gains in
feedlot, dressing percent, and carcass grade are presented in
Table 2.
The means for feedlot performance traits of the various breed
groups of calves are presented in Table 4. Data for weight gains
and dressing percent are presented for unadjusted final weight
and also final weights adjusted to a standard dressing percent
Table 2. Means squares and levels of significance for the various measures
of breeding in feedlot performance of calves.
Carcass Dressing
Source of Variability D.F. Gain Grade Percent
Year (Y) 2 1425 2.58 10.86"
Breeding (B) 4 6391 15.17** 10.33"
Y x B 8 2460 1.37 2.04
Error 90 2995 1.32 3.47
t P<.10
SP<.05
*"P<.01
Table 3. Least squares means by breed of calf for age at weaning, weaning
weight, 205-day weight, and condition score.
Age at Weaning 205-day Condition
Breed of Calf Weaning Weight Weight Score'
SB 215 449 433 9.97
S5Ba 222 448 421 9.85
SsBI 221 456 428 10.25
BaSi 220 479 453 9.93
B5S3 214 440 425 9.32
BS 225 409 377 9.22
1 9, Low Good; 10, Good; 11, High Good.
Table 4. Feedlot performance, dressing percentage, and carcass grade of Shorthorn-Brahman crossbred calves.
Breeding of animals B3S1 B5S3 F1 S5B3 S3B1
Number of animals 21 21 21 21 21
Days on feed 191 191 191 191 191
Initial weight, Ibs. 544 519 519 541 517
Final weight, Ibs. 950 952 948 953 931
Gain, Ibs. 406 433 429 412 414
ADG, Ibs. 2.13 2.27 2.25 2.16 2.17
Carcass (chilled), Ibs. 586 587 580 572 568
Dressing percentages 61.73 61.63 61.19 60.04 61.07
Results with final liveweight adjusted to 60 dressing percentage
Final wt., Ibs. 976 978 967 954 947
Gain, Ibs. 432 459 448 413 431
ADG, Ibs. 2.26 2.40 2.35 2.16 2.25
Dressing percentage 60.00 60.00 60.00 60.00 60.00
Carcass grade 10.00 11.00 12.00 11.70 12.00
Feed/100 Ibs. gain 875 895 902 905 896
1 10, Good; 11, High Good; 12, Low Choice.
of 60%. Differences in gains of the various breeds (P<.10) were
not large, agreeing with previous findings by Peacock and Kirk
(12). There was a tendency however, for Fi and BsS3 to gain
more than the other breed groups.
Carcass Grades
U.S. Carcass grades varied from Good for the B3S1 and High
Good for the B5S3 to Low Choice for the Fi, S5B3 and SsB1. There
were highly significant (P<.01) differences in carcass grade be-
tween the BsSi and Fi, S.Ba, and S3B1 as well as between BsS
and the Fi breed groups. A significant difference (P<.05) existed
between the B.sS and S3Bi breed groups. Carcass grades were
non-significant among the Fi, SaBs, and SaBi breed groups, all
averaging in the Low Choice grade. These results show that the
Brahman-Shorthorn steers with more than one-half Brahman
breeding had the potential for grading in the Good grade but on
an average lacked the potential for grading Choice. The Fi and
predominantly Shorthorn steers reached the Low Choice grade
under the same managerial conditions. Carcass studies by Car-
penter et al. (4) showed that increased grade and percent fat
were associated with increased Shorthorn breeding and decreased
as Brahman breeding increased.
Dressing Percent
Dressing percent, based on chilled carcass and pen weights,
varied significantly (P<.05) among breed groups, varying from
a low of 60.04 for the SBB3 calves to a high of 61.73 for the B3SS
calves. There was a tendency for dressing percentage to be high-
er for groups where Brahman breeding exceeded one-half. The
relatively high dressing percentage for the Brahman breed agrees
with studies by Carpenter et al. (4), and also Butler et al. (3)
who found that the advantage in dressing percentage for steers
of Brahman breeding was due primarily to less fill and a smaller
digestive tract.
Feed Per 100 Pounds Gain
Feed per 100 pounds of gain was not statistically analysed due
to the limited degrees of freedom from group feeding. However,
from overall averages there appeared to be a tendency for efficien-
cy of feed for gain to positively related with percentage of
Brahman breeding. Feed for gain varied from 875 pounds for the
B3St to 905 pounds for the SsB3 calves. Earlier studies by Pea-
cock and Kirk (10) showed a similar trend.
The data in this trial, both on weaning and feedlot perform-
ance, are in general agreement with other studies in Florida
(2, 4, 5, 9, 11, 12, 13, 14) and elsewhere (3, 6, 10). The most
significant feature of the study is that it demonstrates cross-
breeding with the Brahman and Shorthorn breeds can be utilized
to achieve good maternal performance in the cow herd and that
steer progeny produced in the programs can be fed into the
Choice slaughter grade within a feasible length of time and at
generally preferred carcass weights.
Steers predominantly of Brahman breeding failed to success-
fully reach the choice grade; however, a shift in demand toward
leaner carcasses, combined with the consistent slight advantage
in feed conversion for these groups, would improve the compara-
tive value of these cattle.
The better understanding of crossbreeding principles and the
choice of proper breeds for crossbreeding, may lead to the dis-
appearance of any disadvantage for the Brahman sired steer. In
any case, the tremendous advantage for Brahman crosses in calf
production makes their utilization in finishing programs impera-
tive for Florida and the remainder of the Southeast. A need for
more intensive investigation in finishing of these cattle is in-
dicated.
SUMMARY AND CONCLUSION
Data from a breeding system that utilized Brahman (B),
Shorthorn (S), Fi, and backcross dams to produce BS, SB, B3Si,
S3Bi, BsSs and S5B3 calves are presented. Highly significant
(P<.01) differences between breed groups of calves were ob-
served for both weaning and condition score. The heaviest wean-
ing weights were from calves out of F1 dams, averaging 479
pounds and 456 pounds, respectively, for BaSi and S3Bi calves.
The lowest weaning weights, 409 pounds, were from Fi calves
out of Shorthorn cows, while the reciprocal of this cross pro-
duced calves weighing 449 pounds. The S5B3 and B5SS calves
weighed 448 and 440 pounds, respectively. The average weaning
condition scores by breed group were 10.3 for SaB3, 10.0 for SB,
9.9 for BaS1, 9.9 for S1B3, 9.3 for BsS3, and 9.2 for BS (P<.01).
Carcass grade increased as Shorthorn breeding in the calf in-
creased to one-half (P<.01), with the Fi, SaB3, and SaB3 having
the same average carcass grade. The B3St calves graded Good;
B5S3, High Good; and the F1, S5B3, and SaBi calves averaged Low
Choice in grade. There was a significant increase (P<.05) in
dressing percent as proportion of Brahman breeding increased.
Daily gain in the feedlot by breed group was 2.27, 2.25, 2.17, 2.16
and 2.13, respectively (P<.10) for the B5S3, Fi, S3B1, SB3, and
B3S1 groups.
These data demonstrate that systematic crossbreeding with
the Brahman and Shorthorn breeds can be utilized to achieve
superior maternal performance in the cow herd and that steer
progeny produced in the programs can be fed successfully into
the choice grade with practical feedlot rations.
LITERATURE CITED
1. Baker, F. S. Procedure for weighing cattle in and out of feedlot and
pasture experiments at North Florida Experiment Station. NFES
Mimeo, Nov. 28, 1967.
2. Baker, F. S., A. Z. Palmer, and J. W. Carpenter. Brahman x European
versus British breeds. Chap. 27, pp. 277-284, Crossbreeding Beef
Cattle. Series 2. University of Florida Press, Gainesville, Florida.
1973.
3. Bulter, O. D., R. L. Reddish, G. T. King, and R. L. Simms. Factors
contributing to the difference in dressing percentage between Hereford
and Brahman x Hereford Steers. J. Anim. Sci. 15:523. 1956.
4. Carpenter, J. W., A. Z. Palmer, W. G. Kirk, F. M. Peacock, and M.
Koger. Slaughter and carcass characteristics of Brahman and Brah-
man-Shorthorn steers. Fla. Agr. Exp. Sta. Tech. Bull. 680. 1964.
5. Crockett, J. R., R. W. Kidder, M. Koger, and D. W. Beardsley. Beef
cattle production in a crisscross breeding system involving the, Angus,
Brahman and Hereford. Fla. Agr. Exp. Sta. Tech. Bull. 759. 1973.
6. Damon, R. A., S. E. McCraine, R. M. Crown, and C. B. Singleton.
Performance of crossbred beef cattle in the Gulf Coast Region. J. Anim.
Sci. 18:1:437. 1959.
7. Duncan, D. B. Multiple range and multiple F tests. Biometrics, Vol.
II, 1955.
8. Harvey, Walter R. Least squares analysis of data with unequal sub-
class numbers. A.R.S.-20-8. U.S.D.A. 1960.
9. Kidder, R. W., M. Koger, J. H. Meade, and J. R. Crockett. Systems of
crossbreeding for beef production in Florida. Fla. Agr. Exp. Sta. Tech.
Bull. 673. 1964.
10. Koger, M. Alternative procedures for crossbreeding. Chap. 44, pp.
448-453. Crossbreeding Beef Cattle Series 2. University of Florida
Press, Gainesville, Florida. 1973.
11. Koger, M., F. M. Peacock, W. G. Kirk, and J. R. Crockett. Heterosis
effects on weaning performance of Brahman-Shorthorn calves. J.
Anim. Sci. 40:1 pp. 826-833. 1975.
12. Peacock, F. M., and W. G. Kirk. Feedlot performance and carcass
grade of Brahman and Brahman-Shorthorn steers. Fla. Agr. Exp. Sta.
Bull. 597. 1963.
13. Peacock, F. M., W. G. Kirk, E. M. Hodges, W. L. Reynolds, and M.
Koger. Genetic and environmental influences on weaning weight and
slaughter grade of Brahman, Shorthorn and Brahman-Shorthorn cross-
bred calves. Fla. Agr. Exp. Sta. Tech. Bull. 624. 1969.
14. Peacock, F. M., W. G. Kirk, J. W. Carpenter, M. Koger, and A. Z.
Palmer. Feedlot performance of straightbreds and crossbreds. Chap.
29, pp. 295-297, Crossbreeding Beef Cattle Series 2. University of
Florida Press, Gainesville, Florida. 1973.
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